I am at 1600 right at 20psi in 4th w/ .98v a/f. Just curious what you guys get.

I don’t think this crap 91 octane is gonna do it anymore back down to 18psi

Yesterday I was running 15psi on the highway in 4th and 5th and my EGT's were just barely over 1400 on 91 octane. You sound a little hot there Brian, it might be time to make a run to Duggans. :-)

hey guys, sorry off topic but what are you setups for running 15 psi. i plan on doing this very soon and am starting to gather stuff. also anything else you would recommend. i am going to try and run 100shot direct port too. rebuilt bottom end of course. any suggestions will be appreciated.

your using 91 oct..... a little crazy if you ask me.............. and your egt are a little high.... your running a little lean.....

at 1400 degrees your definately safe but your robbing yourself of power too...at any psi 1500 or 1550 is not to hot...getting upwards of 1600 is pushing close to the edge but your running really rich at 1400 degrees...better safe than sorry but slower than it could be...i will be turning it up to 19 probably when my dis to gets there this week and i'm going to tune to keep it right about 1550, that way its running nice and strong, i dont want to be much lower, maybe 1500 at the lowest....your just robbing yourself of power w/ anything lower, w/ those egts i'm not to worried about detonation..and if you can use 94 super from sunoco if its available, thats all i use

I tune egt's for the top of 3rd at the track. I shoot for just under 1600 degrees at 6800 rpms in 3rd gear. The rest doesn't matter (to me anyway). Your egt's will be higher at the same boost level in each higher gear as you approach redline, due to the increased load the gear ratio puts on the engine. I will probably never be in a situation where I'll be at a full 20 psi in 4th for very long (I go through the traps in 4th, but just barely), so I don't tune for that.

My highway runs yesterday weren't thru the whole gear. I would go WOT for a few seconds, then let off. (tryin to get one of those new supercharged Cobras to go)

When I run a true 1/4 mile, I end at the top of 3rd or the bottom of 4th with my EGT's at about 1500-1550. I ran 93 octane at the track last time I went, and I'll probably run a higher octane next time. The only reason I'm driving around with 91 octane now is because I drive 50 miles one-way to work each day, so I don't do much boosting. Higher octane gas isn't easily accessible here in Colorado, we don't have Sunoco.

Sorry for getting off topic but how do you guys know what your EGT's are supposed to be during what gear? I meant the EGT needle constantly goes to 1600 as you get faster and faster right? So how do you know what your EGT's are supposed to be at a certain boost level? Doesn't everybody hit 1600 eventually?

>your using 91 oct.....

Yep most of the time. when I can I put some 110 in w/ it.

>a little crazy if you ask me

I didn’t ask

>and your egt are a little high....

Not really

>your running a little lean

Between 98-1.01v is lean? no. The car is tuned for ~11:1 af that really isnt too lean

Remember this is 20psi. I did a little tweaking w/ the power controller and the base map and got it down to ~1570.

Thanks guys
Brian

Are you retarding the timing any at 20 psi? .98 o2's is pretty rich, but that is about right for that boost level. IMO, you may be getting some *slight* detonation, which may be making you run a tad bit hot, esp running 91 octane. I'd bet if you ran higher octane, that your EGT's may decend slightly. Maybe pull one or two degrees of timing, and that may help. But it sounds like you got it fig out :thumbsup

i guess if there is anything that you can appreciate the mid west its sunoco super 94...good stuff, rather expensive but good stuff...i dont know what egt probes you guys run but i highly highly recommend the tre probe, its like 45 bucks and is the best one i've come across..he he...its lighting fast reaction time is great and its very accurate from what i can tell...your egts shouldn't get over 1600, your on the edge as it is running that high but still ok..if your guage only goes to 1600 then try to keep it a hair below that mark...your egts could be from advanced timing, not enough fuel or to much fuel causing afterburn..only true way to tell is monitor knock(???), use a wideband o2(expensive) or trust in your o2 guage and egt..most likely you'll be running hot from being lean, you'd have to be pig rich to be getting a lot of afterburn...try to get a datalogger too

If you have an ignition and are pulling out timing, you may be pulling out a little bit too much. When you retard timing, you will see higher egt's. Although by using 91 octane, I would be real careful advancing timing if you decide to try that. I would think that around 12 degrees advance would be fairly close at that boost level.

Yes, I run an ignition (Crane Digital CD) And yes I pull a little timing out. I run 18-20 deg advance at WOT, I have had zero problems running that timing for the last year. It is actually right where you want it to be.

It was more of a where you at question than a is this ok question.

This reading was in 4th gear, WOT, full boost, ~6500 RPM and ~115 MPH.

I'm good to go and I can always write a new fuel map and pull more timing if needed.

As always thanks
Brian

so what is an acceptable timing value of advance?? i am thinking my car was at 17 deg of advance at wot when we datalogged it running 11 psi, now i'm running 15 and will be 20 this week when i get my dis2...are you guys saying at 20 lbs i should be at 18-20 degrees?? this has been a question of mine in another post that noone helped me w/...where should it be?? anyone have a good way to calculate this or what is the "accepted" value of advance for specific psi?? thanks...

My egt is about 1550 at the top of 3rd and about 1500 in 4th. I believe too much timing retard and too little will affect your egt reading. When I last datalogged my car, retarding timing by about 8-9 degrees seems to be optimal for about 17-18 psi. Anything more and you lose power; anything too much less and you begin to detonate.

Brian (Justone), I think you've got a pretty decent fuel setup. I just think your high egt is probably from the 91 Octane, since your air/fuel is actually very rich. At the top of 3rd, my air/fuel is about .96V.

>My egt is about 1550 at the top of 3rd and about 1500 in 4th.

What???

How do your EGTs go down as you go faster? Mine just keep rising the faster I go.

its all about having a programmable fuel map man, w/ their setup w/ the dfi you can add fuel where ever you want, w/ my 8 inj setup i can have the eic give me 15% more fuel at x rpm or x map setting...great to have that kind of tunability to try to flatten things out and not just guess everywhere...so kon werent you pulling like a degree per lb of boost?? i thought thats what jp told me..i was thinking 1/2 degree per lb..what do you think?? the dis2 is very flexable when it comes to this, i can make my own graph to pull or advance...thanks men

I'm pulling approximately 1/2 degree per pound of boost. From the datalogging, I've found that about 12 degrees of retard is the most I can retard. I tried 1 degree of retard per lb. of boost, and the car gets real "sluggish" during initial acceleration from the high timing retard; plus the egt climbs towards 1600 fast!

sounds good ...i guess this is the value i'll start w/...see how the egts stay and go up from there...thanks man...o btw if you need some help getting it back to top performance let me know