So I'm thinking this is better;




Compared to this;





Did some machining work with my buddy Steve and came up with 5 1/2" runners for higher power range. Haven't dyno'ed it or anything, just showing the work.

:eek :bowdown

Effing awesome Mark! Can't wait to see the dyno results.

so sexy

I would imagine that taking that bend out will DRASTICALLY help the top end! Awesome Mark, ready to see some numbers!

Originally posted by Slo2g
I would imagine that taking that bend out will DRASTICALLY help the top end! Awesome Mark, ready to see some numbers!

This. Looks efffing amazing mark. Bet it sounds ungodly

Thanks guys.

Originally posted by RoninEclipse2G
:eek :bowdown Effing awesome Mark! Can't wait to see the dyno results.

Neither can I. Finding time has been tough this winter. Too many projects and life wants to intervene. I have intake on with injectors etc, I just have to wire in the TPS and she should be ready to tune.

Originally posted by Slo2g
I would imagine that taking that bend out will DRASTICALLY help the top end! Awesome Mark, ready to see some numbers!

I'm thinking the short straight shot will help get me the rev's I so desire, lol. Slightly concerned about the space between the firewall and the top of the velocity stacks (approx 3"). But I'm figuring its enough.

Originally posted by Fotowntalon
so sexy

Yeah, gotta admit that ITB's always have a pretty cool look to them.

Originally posted by 420agreenvilleSC
Bet it sounds ungodly

Well, I'm hoping its motorcycle quality :P

Awesome

Yeah, that is close to the firewall, hopefully it doesn't choke the air from the horns and create dead spots in your power band.

Time to cut holes in the firewall...

Originally posted by 740 turbo brick
Time to cut holes in the firewall...

Maybe just create an airbox around the velocity stacks so that the stuff by the firewall won't mess with the flow.

Originally posted by RoninEclipse2G
Can't wait to see the dyno results.

And the results are in.......

Got to the dyno today with the ITB's (Ah, the money I spend in the interest of satisfying curiousity). Well, I was concerned about the size of the TB's (42mm) and apparently for good reason. These TB's would make a super excellent street set-up, but not so much for a high reving strip car. The throttle response is outstanding, the torque curve is higher (than my 219.4whp pull), the power curve is higher, and the power curve is straighter. Sounds great right?

Nope, read it and weep, lol (This is a comparison of the ITB run vs the 219.4whp, 65mm throttle body run);



The red is the ITB's (hp and tq). While the blue is the 219.4whp, 65mm TB run. You can see how the ITB run stays well above the 219.4whp run by plenty at first (in both power and torque). But as we approach the 6k mark, the ITB's start choking out. By the 6500 mark you have the cross over for the 65mm single TB to take over. The ITB's just fall on their face. They are too small.

Oh well, all in the name of science. Though we did gather a bit of information. If I still had a daily 420a, I would be all over these for the street. Look at all the torque and power and throttle response you would have in the range that you would normally drive your car around (go ahead, I dare you to pull on me around town, lol). And you know what else? These fuckers idled. Were talking right about 900rpm with Crower 3's and they idled nice and smooth. Sweet. And obviously, if you change to the C shaped original intake, you'll see even more down low.

Now, what this hints to, in reference to the 12.5 engine; I may have more power to pull out of those cams. If you were to follow the ITB curve up and extrapolate from where they fell off (as in continue the line up), It kinda gives you the impression that at peak power for the crower 3's (which is more like 7700) one could infer that we would be around 230whp. Hmm, curious.

very interesting, so when are you swapping out the TB's on the ITB for bigger ones? =P

Originally posted by Fotowntalon
very interesting, so when are you swapping out the TB's on the ITB for bigger ones? =P

Well, seeing as how I just hit the dyno yesterday, I woud think I could take some time to digest this......................ok, long enough ;-). I'm going down to my TB pile this morning and start picking through.

Do you think the lack of airflow at the upper rpm from being behind the motor has anything to do with it? I think a subaru style hood with the vent being further back would benefit this a lot. This is an awesome gain over the plenum though for sure. Another question that comes to my mind, what are you doing with the original intake manifold? I know a few people on here would LOVE to get their hands on something like that, of course if you are through with it. I also think its funny how the normal NA "dip" moved lower in the power band vs a conventional plenum intake. Anywho, like always I'm super stoked on seeing what else you have in mind/store for the next thing.

Originally posted by Slo2g
Do you think the lack of airflow at the upper rpm from being behind the motor has anything to do with it?

This was a point I considered. But I don't think so because, basically the amount of room behind the velocity stacks is the depth of a standard SMIM plenum. Except for the fact that it is a lot bigger area for the TB's to draw from. So I am thinking that I have plenty of draw. In addition, the Honda/nissan guys I know who have done this, use 52mm to 60mm throttlebodies. 60mm is a little too big for my tastes, but I'm thinking stock 420a TB's (Since I got 4 here, lol) are the way to go.

But what I was considering about that area was using my long ass "horn" intake to direct some air into the area, so that it gets some cooler air instead of trapped air (possibly even building an air box around them.....we'll see).

Originally posted by Slo2g
I think a subaru style hood with the vent being further back would benefit this a lot.

Yup, I hear you on that. I just picked up (over the winter) an "Evo style" hood for a 2g. It has a grid more to the center back of the hood. I liked the idea to get some air across, though I'm not fond of the fact that it "humps up" a little higher than stock.

But I hear what you are saying about getting some air in there. We've (buddies of mine who are helping me discuss options) discussed the fact that, in real world application, these MAY not be a better option than my "Ram Air Horn" intake with a single 65mm TB. Not sure if the gains of the ITB's will outweigh the loss of the "forced induction" (lol) of the horn.

Originally posted by Slo2g
Another question that comes to my mind, what are you doing with the original intake manifold? I know a few people on here would LOVE to get their hands on something like that, of course if you are through with it.

Lol, yeah, I figured that someone would like it. Like I said, I wish my daily was still a 420a. I would love to try it.

Yeah, when I'm done, I imagine they'll go up for sale (with throttle bodies and all. I haven't done anything that would keep them from going back on).

Originally posted by Slo2g
I also think its funny how the normal NA "dip" moved lower in the power band vs a conventional plenum intake.

That little fucker is something. She moves around a little depending on the set-up. I even had one set-up that just about smoothed it out (but I can't remember what set-up it was, lol).

Appreciate the input for the thought process.

MB

I think having a box around these things that feed into a velocity stack like you had on the single 65mm set up would give you great wtq and allow it to breath up top and POSSIBLY give you the "forced induction" you get from the ram air effect. Having a box around the itb's is always a hit or miss kind of thing, too big and its doing no good, too small and your choking the itb's. Meh, anywho, I know you'll continue on the path and have even more amazing things in store for us...

If you were to build a plenum around the stacks, you'd then also have the option of being able to apply some resonance tuning.

Now what could this stuff be?









For starters;



Four stocker 52mm's. How am I gonna do the throttle linkage? Got no fucking idea right now, lol. Bolt them on? Haven't the foggiest yet.

LOL, awesome, nice case of the F-its and lets start cutting stuff up to make it fit! Do keep us posted!

this is my mood 90% of the time. Wish I was there with ya Mark, I'm a problem solver. I'm sure that the Morpheus build can help you a lot in your goal as well.

Originally posted by Slo2g
LOL, awesome, nice case of the F-its and lets start cutting stuff up to make it fit!

Bingo^. Once its done, you can't undo it, so you gotta figure out what to do next, lol.

The old "throw your hat over the fence" story.

Originally posted by 740 turbo brick
LOL, thats the spirit. Youre MB, youll figure it out.

Hahaha how's that 4g63 working out for ya?

Originally posted by Fotowntalon
this is my mood 90% of the time. Wish I was there with ya Mark, I'm a problem solver. I'm sure that the Morpheus build can help you a lot in your goal as well.

Yeah, I checked through his posts after I did the dyno. I meant to read it before, but I forgot. I'm actually trying to source out velocity stacks and he gave me a couple of avenues.

Custom throttle plate rod? If you could run one rod through all 4 throttle bodies that would make things simpler.

Would it be possible to make the outlet sides work with V band clamps? Then you wouldn't need to bolt them on.

Originally posted by RoninEclipse2G
Custom throttle plate rod? If you could run one rod through all 4 throttle bodies that would make things simpler. Would it be possible to make the outlet sides work with V band clamps? Then you wouldn't need to bolt them on.

Look at you go! Yup, both great ideas that we have been exploring. The V-band clamps, while a great idea, would take a bit more time, and make for a basic re-do of the set-up. Don't know if I really want to do that yet - though its not a ruled out possibility. It does give us adjustability.

As for the single throttle rod through all four TB's; that would require a bit of time in measurement and preciseness, that may not be necessary. I'm leaning toward adjusting the plastic throttle arm (or make a stainless arm) so that it would be about 45* in a clockwise position, so that I can make a "lever" to pull on all four at once. This could allow for adjustment in various different directions.

Originally posted by bullettdsm

Originally posted by RoninEclipse2G Custom throttle plate rod? If you could run one rod through all 4 throttle bodies that would make things simpler. Would it be possible to make the outlet sides work with V band clamps? Then you wouldn't need to bolt them on.

Look at you go! Yup, both great ideas that we have been exploring. The V-band clamps, while a great idea, would take a bit more time, and make for a basic re-do of the set-up. Don't know if I really want to do that yet - though its not a ruled out possibility. It does give us adjustability. As for the single throttle rod through all four TB's; that would require a bit of time in measurement and preciseness, that may not be necessary. I'm leaning toward adjusting the plastic throttle arm (or make a stainless arm) so that it would be about 45* in a clockwise position, so that I can make a "lever" to pull on all four at once. This could allow for adjustment in various different directions.

I immediately thought of a single throttle cable with three additional ends crimped on.

___/_/_/_/

Pull all four at once...

Originally posted by DarkOne

Originally posted by bullettdsm

Originally posted by RoninEclipse2G Custom throttle plate rod? If you could run one rod through all 4 throttle bodies that would make things simpler. Would it be possible to make the outlet sides work with V band clamps? Then you wouldn't need to bolt them on.

Look at you go! Yup, both great ideas that we have been exploring. The V-band clamps, while a great idea, would take a bit more time, and make for a basic re-do of the set-up. Don't know if I really want to do that yet - though its not a ruled out possibility. It does give us adjustability. As for the single throttle rod through all four TB's; that would require a bit of time in measurement and preciseness, that may not be necessary. I'm leaning toward adjusting the plastic throttle arm (or make a stainless arm) so that it would be about 45* in a clockwise position, so that I can make a "lever" to pull on all four at once. This could allow for adjustment in various different directions.

I immediately thought of a single throttle cable with three additional ends crimped on. ___/_/_/_/ Pull all four at once...

Uh huh, uh huh, hmm....let's see, I might have to extend the groove along the bottom of the arm (angle too tight?), but cables would allow for play within the system.....hmm, looking at it, it may be just too tight an angle......but...hmm, that idea definitely has some merit :scratch

Originally posted by bullettdsm

Originally posted by RoninEclipse2G Custom throttle plate rod? If you could run one rod through all 4 throttle bodies that would make things simpler. Would it be possible to make the outlet sides work with V band clamps? Then you wouldn't need to bolt them on.

Look at you go! Yup, both great ideas that we have been exploring. The V-band clamps, while a great idea, would take a bit more time, and make for a basic re-do of the set-up. Don't know if I really want to do that yet - though its not a ruled out possibility. It does give us adjustability. As for the single throttle rod through all four TB's; that would require a bit of time in measurement and preciseness, that may not be necessary. I'm leaning toward adjusting the plastic throttle arm (or make a stainless arm) so that it would be about 45* in a clockwise position, so that I can make a "lever" to pull on all four at once. This could allow for adjustment in various different directions.

Im gonna be honest with you... most of what you say goes right over my head however thinking about what your looking for could you make your own multiple throttle linkage "thingy" (technical jargon) like what multi carb hot rod people do? A design kinda like this...
http://www.forwhatyouneed.com/carburetor_linkage_progressive.htm
and instead of the grove plate for the cable going to more of a rod arm like these...
http://www.thehotrodcompany.com/shopnow/show_dept.asp?dept_id=50&filterkey=cl
You probably are already working on something and I am probably too late but it is what it is.

Originally posted by Shake_Zulla
thinking about what your looking for could you make your own multiple throttle linkage "thingy" (technical jargon) like what multi carb hot rod people do?....You probably are already working on something and I am probably too late but it is what it is.

You gotta remember I'm trained as a teacher, so "brainstorming" is always welcome.

Kinda looking at something like the multiple hole set-up for the linkage as well (Dino's idea notwithstanding). But what we want to do is make the throttle pull on the throttle body a circle with multiple holes so that we have a choice as to where we want the pull to be. Stevie called it the Choo-Choo train design, lol. They show a lever in your link, we're thinking a circle.

Originally posted by bullettdsm

Originally posted by Shake_Zulla thinking about what your looking for could you make your own multiple throttle linkage "thingy" (technical jargon) like what multi carb hot rod people do?....You probably are already working on something and I am probably too late but it is what it is.

You gotta remember I'm trained as a teacher, so "brainstorming" is always welcome. Kinda looking at something like the multiple hole set-up for the linkage as well (Dino's idea notwithstanding). But what we want to do is make the throttle pull on the throttle body a circle with multiple holes so that we have a choice as to where we want the pull to be. Stevie called it the Choo-Choo train design, lol. They show a lever in your link, we're thinking a circle.

Ahh that is a good idea. I would suggest making several sizes of the drive pulley (Im just going to call it a pulley) that the throttle cable attaches to. That way you can adjust your throttle response by increasing the diameter of your drive pulley.

Here's an idea. Two linkages attached to the factory bufferfly levers. One above and the other below, so that as one lever pulls (and attempts to cant off) the other would push. The two linakges would not be able to cant toward each other. Since the levers can only move 90*, you can mount the linkages so that they have maximum distance between the two at 45* (one on "top", one on "bottom"), they will not collide with each other and should hopefully still be able to provide enough angular force at 90* to fully open the last butterfly.


Or, alternatively, turn the TB's so that they all share the same pivotal line and attach the shafts. Then either use the lever on one TB and a different AoA for your TB cable, or use the lever/linkage assembly from the other ITB setup.


A rack and pinions would be ideal for the pictured orientation - if not clunky, difficult to implement, and expensive. :)

Just throwing it out there.

edit: when I say lever, I'm talking circular.

Originally posted by Locke_db
Or, alternatively, turn the TB's so that they all share the same pivotal line and attach the shafts. Then either use the lever on one TB and a different AoA for your TB cable,

Three O'clock in the morning and I just got home from playing with the ITB's with my buddy Stevie (paraquat on here. Can't say enough for the help that he has given me. Not just in making the parts but being the final "bouncer of ideas"). After WAY too much time thinking (well it always seems that way. I'm impatient. I want to jump right on it) about what we wanted to do, we decided on a direction with most of the issues addressed. We mocked the TB's up in various positions and considered pretty much all that you guys have talked about.

Ended up turning the throttle bodies 90* and we are using one axis to turn the throttle. We are intending to use couplers (with set screws is the current idea) to mate them together. Got the TB's ported and cut down to size tonight (we also had to help one of his co-workers pull a tranny so we lost some time).

Stevie did get some pics, but I don't know if/when he will upload them.

Hey its a start.

Pics

Tore them down and, of course, cut them down;


Then bored them out;



and then cut down the throat and smoothed out the exterior (just in case we need to attched to it.


We also addressed vac leak issues for the IAC that was cut off and the small evap breather that comes out of the top.

So steps of progress. As always I like to show you as I go so that you can see it takes some time and figuring to do modifications like this. And sometimes you can change your direction midstream because of obstacles that you don't forsee. In addition, you may go through ALL this work only to find that it either doesn't work/fit, or works poorly(as in the previous foray into the 42mm throttle bodies; great for the street, but can't help me in my race car).

LOL, thats the spirit. Youre MB, youll figure it out.

Been following this thread, AWESOME! You might end up possibly mounting something off of the valve cover to connect to the tb's? Keep up the great work!

Looking at the throttle linkage design, my thought would be to perhaps combine two ideas into one. Instead of using levers, just make swivel extensions and mount them where the throttle cables normally go. Instead of having to be stuck with trying to run a rod or cable in the original manner, you'd be able to run a threaded rod right on the side of the throttle arm though all TBs. Plus, using two lock nuts on either side of the extensions would give you a great degree of fine tuning each ITB. The only part of this idea that might require some extra work is the throttle arm you need to hook the actual cable to. You might need to machine an aluminum one with provisions for both the threaded rod and cable end. Just throwing my idea out there. :)

Damn, MB. You never cease to amaze. :bowdown

This is something I always wanted to do, and here you've done it, have the DSG paper to prove it, and have figured out a better solution.

You, sir, are a Gearhead God.

Just saying.

Looking forward to seeing you and the beast in Norwalk this summer.

Originally posted by DR1665
Damn, MB. You never cease to amaze. :bowdown This is something I always wanted to do, and here you've done it, have the DSG paper to prove it, and have figured out a better solution. You, sir, are a Gearhead God. Just saying. Looking forward to seeing you and the beast in Norwalk this summer.

Hey B, good to hear from you. I knew you would eventually get on the ITB post, lol.

As far as the stuff you always wanted to do, my story goes like this; When I first got on here, I read quite a few of your posts and ideas. I really liked the dedication and passion for staying Na. So, I said to myself, "Self, I want to be just like Brian". So everything I have done since that point has been in honor and memoriam to you, Oh Great Ghost of 2gnt's past :bowdown


Lol, alright, so some of that is sarcasm and tongue in cheek. But honestly, you have been an inspiration and knowledge base for a lot of what I have done. For that, we thank you :cheers

Sarcasm or not, you just made my day, Mark.

You've got me thinking, 97 ESi 5-spd, your rev. A ITB setup (on the curves), very mild head work, Crower 2s, LTH, MSnS would make for a fantastic hedge against $4/gal.

Inspiration comes full circle. ;)

Hey kids and squids, Bullett asked me to chime in. I think that was only to post the pics. Unfortunately I was out all day but it looks like he figured out photobucket.
We keep kicking ourselves to bring a real camera with us to the shop.

We had a couple ideas:
a long bar with some chain links or shoulder bolts/ball and sockets
4 disks like stock throttlebody cable adapters
some wagonwheels or train wheels
finally settled on rotating them 90 degrees and trying to finagle some couplers in between them

Solving for the throw of the arm isn't bad on a TB. The plate closes and 90 degrees later there is a stop for the arm. We can put the stop anywhere so it opens worlds of possibilities. When I did a boost actuated cutout I had to solve for the chord. I had x amount of throw from the actuator and had to translate that into 90 degree movement. That sucked.

I tried selling him on one solid rod. There were a lot of pros to this like the shaft being 3/8" diameter. We have tons of 3/8 stock laying around. They would all be synchronized if the shaft was one piece also. But the cons started to quickly outweigh the pros. Because the throttle bodies are all cast garbage made of old beer cans and door knobs they're drastically different. Just between two throttle bodies I measured ~.060" difference. The height from the base of the TB to the center line of the shaft would have to be perfect or it'd bind or bend or the plates wouldn't close all the way.

I brought a block of 2x3 aluminum out of the stock room and said "Why don't I just bore this out for you?"
That would've been easy to get all the holes in line, mounting flanges all the same, I could've done all 4 in no time and there wouldn't be any leaks because of ISC or what have you.
Bullett replied "Because I get a hard on using stock parts"

I put the original ITB setup in my machine but because the stock manifold is cast the dimensions were all over the place. I had all the dimensions for the hole pattern on the 42mm but when I indicated each velocity stack and put a dimple where the holes were they didn't line up. Whoever did the original ITB setup with the 42mm's might not have had access to equipment like this. In the end we had to just eyeball where the holes were. Even then we still encountered binding because the 42mm's were welded together.
This would've made the one long shaft more of a pain to line up.

So we settled on the stock TB's, bored out, and a coupler in between. The coupler will just be a sleeve with 2 set screws in each side. This will let us swing the TB's around to get them over the velocity stacks and because we can make them any length necessary we can suck them in or move them out accordingly. The coupler will also let us set each TB in a closed position. Another problem with one solid shaft and the dimensional inconsistancies would be, as an example, that 1, 2, and 4 might've been fully closed but 3 would be partially open. The #1 TB will retain the cable attachment and the #4 will retain the TPS.

And it was me that dropped the ball on the original ITB setup pics but I put them all on photobucket now. Sorry for any repeats.

This is the original 42MM ITB setup on my machine with the "velocity stacks" I made. It's only a 3.5 degree angle into the runner.

We gave up trying to do things by the book and just eyeballed the holes. That's Bullett opening up the holes.

Trying to get the linkage working.

Linkage all set up

Bolting them in.

42MM set up finally done.

The cable attachment on the back.


The stock TB's. Already "contoured" by Bullett with a band saw.

Locked and loaded.

We shortened the TB's by almost half an inch to match the height of the 42MM's.

I turned the outside to clean it up a bit. It's also now a standard dimension. In the future we'll try to find some 52mm velocity stacks. This will let us do almost anything to attach them. It also provides me with a concentric diameter and square shoulder if I needed to flip it around for any reason.

Painted up, boring out.

2.047" ID
When we made it a straight 52mm bore all the way through it almost entirely cleaned up at the inlet. You can see there's just a tiny ring of red paint left over on the very edge. Almost like the half inch we took off was planned. I mean, we did plan it that way. From the start.

Hand polished to finish it off. Then do it 3 more times.

And that's where we're at now. I've never had any real formal training so I'm not really sure what's going to happen. We're kind of barreling headfirst into this so it's gonna be interesting. As Bullett mentioned if you have an idea you wanna brainstorm then toss it out there. Next time he sees me he'll take full credit for your idea. :P


--Steve

Originally posted by Paraquat
I tried selling him on one solid rod.

Haven't we all, sir. Haven't we all.

:order

Just playing. Makes me wanna take a few TBs with me next time I visit my grandpa-in-law. (He's got all that equipment in his garage.)

Keep up the good work, gents. :thumbsup

Originally posted by DR1665
You've got me thinking, 97 ESi 5-spd, your rev. A ITB setup (on the curves), very mild head work, Crower 2s, LTH, MSnS would make for a fantastic hedge against $4/gal. Inspiration comes full circle. ;)

Exactly what I was thinking when I saw the dyno slip! Match those fuckers up with crower 2's and you will get even more power/torque down low. The power band on the C2's starts dropping off in the 6's anyway. The advantage of the LTH (besides more airflow) was that it allowed me a higher power band. I'm not so sure how much difference an E-bay 4-1 header vs the LTH would make.

One thing I wanted to point out from the pics. These throttle bodies were off of various junkers that I got in over the years. If you look at this pic closely;

You will see that, in the throttle body to the left, there are what appears to be waves. Yes, yes those are waves. This is an example of how NOT to port a throttle body. It appears that the previous owner decided to take out the "hump" in the the TB throat with a die grinder (like we did on the machine). Unfortunately, the accuracy was not all that great, lol. he came darn close to ruining the TB because he just slightly ground into the butterfly contact area. It is so slight that I don't think it will be a problem. Maybe at idle, but then again, I can't ever remember racing at idle ;-)

You know, the only reason I have a Dremel tool is because, way back in the day, I decided to open up my TB. Fortunately, I wasn't very aggressive. (Didn't want to junk my ONLY TB.) Fierro was able to clean it up on the lathe.

Here's an idea, though, we've all seen those spacers with the corkscrews in them which are supposed to accelerate the intake charge. Sound theory, but I've never seen such a spacer offer that looked like anything more than a turbulence-inducing gimmick.

Suppose you were to do some rifling pre-/post-throttle plate. I'm thinking something with a lower twist rate. Could be gentle, curving grooves carved into the throat, or something more polygonal (a la Glock, and inspired by those waves pictured above).

Taking this idea a step further, picture this tool in your mind's eye...

Something like a short flex hone designed to be pulled through intake plumbing (CAI, IC, intake runners). Each pad has a carbide cutter bit on it fixed in such a position that pulling the device will result in a fairly uniform rifling within whatever tube it is pulled. The leading side could have some kind of universal joint before a ring where a length of wire is attached, ensuring the tool can freely rotate as it moves forward.

The flex-hone format would allow for fitting in various diameters of tubing, and I suspect tension could be adjusted as desired for depth of rifling. You could even do multiple passes through the same tube to increase the bite, as the tool would trace it's own tracks.

Line up the grooves on either side of the TB with those on the outlet of the intake and I suspect you might have a truly rifled intake for that last 3ft before the IM (generally speaking, since you don't have an IM anymore, MB).

Just a thought.

Beyond that, someone ought to make something like the Cyclone intake for the 420A. I can't wait to try out this dual runner business on my Galant this summer.

Go fast.

Holy crap, this is epic. I want a video to hear this bad boy once finished!

I'm glad there's some interest in this huge waste of time and money :P. One day I'm going to remember to bring the camera to the dyno with me. And that one day I remember to bring it, I will hopefully remember to take a vid of her on the dyno, lol.

Got the 52's pretty much done. Stevie took some pics, but they are on his phone and his computer is on the fritz. All we have left to make is the velocity stacks. Steve's in the process of spinning them now (couldn't find any reasonably priced stacks, so he said he could spin some).

So if these bolt on the car and run (I still need to set-up a throttle cable), I should be back at the dyno relatively soon.

well to re compensate you, if they don't net you the best hp as the 65mm, then I will gladly take them off your hands =P

Originally posted by Fotowntalon
well to re compensate you, if they don't net you the best hp as the 65mm, then I will gladly take them off your hands =P

Heh heh, ACTUALLY, I'm considering parting out my GSX and buying another 420a to put the 42mm ITB's in. I got two 10.5 comp set-ups sitting in the garage right now. I also have a ported head on one of them. In addition, I do have a set of C2's........

And now some update pics;

We made adapter plates for each TB to transfer the 52mm TB to the 42mm holes. We then bored that out for a smooth transfer and drilled appropriate holes for mounting (no pics of any of that. Just forgot at the time, lol)

We decided to spin the TB's so that they use one axis (I still don't think this is the easiest/quickest/best way. But its the direction we chose);



You can see the 3/8 rod we used to line them up (fits perfectly through the TB's). It was a bit of a chore to get them straight since I originally just eyeballed the straight line of the 42mm TB's before we welded the original adapters on. But they were really close anyway.

We then took two throttle boddy shafts and welded them together (welded TB 1 with TB 2 and welded TB 3 with TB 4). Leaving TB 2 and 3 a seperate removable joint for adjustment and ease of removal etc. In this over head pic you can see the rods going all the way through;



and here is a pic of the joint;



You can see we retained the stock throttle stop (but none of the plastic) so that I can have a place for the back two TB's to stop. Instead of just allowing them to twist off the one stop in front (just a little support). We welded a "barrel" on the end of the stop and that fit into the throttle body next to it (the break point between the two sets of throttle bodies).

and here's a pic of thema t WOT;


Welding the rod was fun, in that, when you welded the rod (with the butterfly's in place), the heat expanded everything, so the twisting action of the throttle movement, bound up and made us panic a bit about the welding fucking our whole set-up, lol. But when she cooled, it was back to functioning properly.

Got a little more work to do. From this point, I already polished out the bore and took her apart to RTV the plate on. Just working on spinning the velocity stacks now (decided we couldn't find any for a reasonable price, so Stevie said, "fuck it, we'll make some". I need to fit them on and set-up some kind of throttle cable. We retained the stock throttle arm set-up;


but it obviously has a different direction to deal with.

As for the TPS, we alos retained the stock tongue;



Just hoping that it doesn't interfere with the alternator bracket.

So we're getting there.

Sick.

Originally posted by DR1665
Sick.

This^

Lookin good Mark, I think you will need a bigger gas pedal :thumbsup

You are so badass that I am almost incline to believe that the red splatter is actually the sacrificial blood of several virgins. :bowdown lol Can't wait till it's done.

That looks really nice. Kinda puts it close to the firewall tho.

First of all, I truly am envious of this setup. Like Brian I always wanted to do this. Great work Bullet.

Looking at your latest design I would be a little concerned about your shaft torquing (or twisting) by the time you get to #4 the butterfly wouldn't be as "open" as the first. Is this something you considered and investigated?

*Edit*

Upon taking a second look I see that there is no return spring on each TB, so I doubt my previous concern has any merit. Again good work, and I'm glad that this tread was "alerted" for some reason. Or else I may have never seen it.

Originally posted by micyek
Looking at your latest design I would be a little concerned about your shaft torquing (or twisting) by the time you get to #4 the butterfly wouldn't be as "open" as the first. Is this something you considered and investigated?

Yup. I believe as long as my butterfly's don't bind up, I should be cool. I actually considered putting a spring on the 3rd TB but;

Originally posted by micyek
*Edit* Upon taking a second look I see that there is no return spring on each TB

For the very reason you originally stated, we held off on a spring. BUT we did leave the stop on the second set of TB's so that they would not over torque on the release.

Just waiting on velocity stacks right now........

Originally posted by bullettdsm
Just waiting on velocity stacks right now........

Well, no longer waiting on velocity stacks. My buddy spun these out on his machine;



30mm tall. 52mm opening at the TB with a 6 degree angle from the opening.

So I put these on with good ole JB Weld and diesel hose to hold them in place;



Getting kinda messy in there but she starts right up and runs. Just won't rev up (I never added any fuel, lol). Now I gotta somehow get to the dyno and see where she is now.

Score, paitiently awaiting more dyno numbers :D

Looking good!

Thanks guys.

Originally posted by Slo2g
Score, paitiently awaiting more dyno numbers :D

Yeah, so am I, lol.

When is the scheduled date? Also hows the rebuild coming along?

Originally posted by Fotowntalon
When is the scheduled date? Also hows the rebuild coming along?

Possible Tuesday and the rebuild has ground to a halt. The rods or pistons were the wrong size at the wrist pin. My machinist has the parts and is kinda "backburnering" them. I gotta get on him to move it.

Jesus! Finally!

I'm sorry, but I'm going to have to request a bit more information than that, Mr. Bullett.

agreed!

Taken from a very reliable source :p
MB: FINALLY got to dyno the 52mm ITB's with good injectors. 210whp with the same curve as the 65mm Mustang TB. ITB's for the loss (in drag racing anyway). But interesting stuff anyway.

Me:glad they are finished... wonder wtf the problem is though. cant believe you are losing power with them. have you tried to consult a velocity expert on the situation only thing i can think of is that you are not running the right size tb's for your application

Someone::( The cylindrical area between the firewall and the edge of the stacks, is this area greater than the area of the TB? It probably is, but all those guys worried about proximity might have something going on, especially between each other where they are combating each other for air.

^this makes a lot of sense^

All is not lost. We have a couple ideas but I don't know how much he wants to say.
It's close to the firewall but it's not that tight. It's his fault for wanting a straight shot into the cylinders instead of a curve in the runners.

Edit: I see you sniped those comments from FB. Yes, the injectors were suspect. That was the big great idea.


--Steve

First the 42's;


Then the 52's;


then the comparison:



You can see the drop off's with torque and power in the low range with the 52mm ITB's. By the same token, you can see the extensions in power and torque (as well as the shift in peak power) with the 52mm ITB's

I don't believe that firewall space is an issue, got more than enough room. Cowl induction with a box MAY help at speed, but not sure. My current suspicion is either the ITB's are too small (doubtful) or we have a resonance conflict.

As for torque; the torque numbers fell back to, basically, the same as the 65mm single throttle body. I still like the 42mm ITB's for the street.

Geez it took a long time and lots of effort to get to.....um, pretty much nowhere, lol. But I do have to post up a vid of her running on the ITB's. Just so its out there.

Nice MB.

Now sell me one of the setups.

You can hand deliver in two weeks :)

Originally posted by teklein
Nice MB. Now sell me one of the setups. You can hand deliver in two weeks :)

Lol, probably gonna use the 42mm on the street. We'll see what intake I'll use.

Originally posted by bullettdsm

Originally posted by teklein Nice MB. Now sell me one of the setups. You can hand deliver in two weeks :)

Lol, probably gonna use the 42mm on the street. We'll see what intake I'll use.

Hehe. Just to make this clear, I call dibs :P

Wouldn't you be able to gain some low and mid end with slightly longer runners? Reading all this makes me think (and I could be wrong) that the main issue could be runner length. Everything else seems to have been tried, so that would be where I would look. I understand about having short runners to help with top end, but is it possible to have the runners too short? When referring to a resonance issue, could the firewall affect that in any way? Just asking that more for my education, but in my mind it seems like it could have an adverse effect. It would be a shame if you gave up on the ITBs.

Originally posted by electrohead
Wouldn't you be able to gain some low and mid end with slightly longer runners?

Well, you have to look at the system as the sum of its whole. Starting from the top of the velocity stack to the end of the exhaust. These particular runners have already done 219.4whp (as has the motor etc.). BUTTTTT that was with a single TB plenum set-up. That has a different length than the ITB/velocity set-up (as well as different air flow characteristics). So yes, could the runners be too short? Possibly. BUTTTTTT that is also dependant on the length and diameter of the runners and the shape/diameter of the collector, coupled with the diamter and shape of the exhaust (all these things come into play when talking about resonance. Just the basics. Not going to get into a long drawn out discussion/explanation here).

All the parts and lengths that I put together were based on a theoretical peak of right around 8k. The engine, 65mm TB and LTH never made it to that. They peaked around 7.6 - 7.7k. (now that could be a product of the cam not being enough - which I suspect is part of it). But because we are dealing in theory vs reality, there are little differences like that. We just shoot for ideal and see where we go.

The ITB length and runners were also based (loosely) on the same peak(as well as the velocity stack LENGTH - not diameter and pitch. I made an educated guess on those numbers off some other experiential information) If you look at the peak on the 52mm ITB's you will see it is also right around 7.6k, so we are certainly in the same neighborhood. That brings us to checking resonance pulses (honestly, I didn't go that in depth when designing it. I just figured if I could hit the same peak, I should be at about the same pulses, but that isn't necessarilly true).

So in my long winded way, what I am saying is that yes they could be too short but it would be pretty darned close to being correct.

As for low and mid end vs longer runners, yup, I would probably drop the peak down a little but then would probably have a little more mid range. So what you are saying is that maybe I should put those 52mm's on my curved ITB intake and try that? Great another avenue to check. Thanks a bunch :rolleyes ;)

Oh yeah, because I may or may not keep this 52mm ITB set-up on, I did make a vid of her reving a few times with the 52mm ITB's. Just for posterity;

YouTube.com

Another thing I was thinking might work (but only if you use longer runners) would be an enclosed ITB setup, like the RB26 engines have. That way, you can still use intake piping to feed the engine while moving and keep velocity stacks on each ITB. Best of both worlds in theory, but it should (again, in theory) be close with resonance to a stock intake manifold. I think with that kind of setup, you will still be able to tune and improve airflow using different size and length velocity stacks and utilize the ram air effect from your bumper mounted intake pipe. I know this could open up a world of new obstacles to overcome, but I know that a setup like that can net more power than a regular styled manifold. If it works for Nissans, I don't see why it wouldn't work on our cars. Peak power may be sacrificed (if at all), but the powerband may be broadened and allow the car to pull harder through more of the rev range. Again, this is just my theory. Yeah, my work day is going good enough today to allow me to think about this...

I've been wanting to do this for years but for a boost box and not intake pipe!

Talk about trailer queen, the thing gets worked on on the trailer!

Originally posted by 740 turbo brick
Talk about trailer queen, the thing gets worked on on the trailer!

Lol, like a doggy in the car, always hoping to go for a ride.