Ok, so I was going to build a 2.4 with an HRC 20g, but now i'm more than likelly going with a 2.0 fully built... but i cannot decide what turbo to get...

Not sure if I want to go with the 20G now... i'm thinking more like a T3 style turbo... but what size to go with? Looking for something about the size of the 20G... has to be bigger than a 16G, but not too big that spool is real late.... so what does everyone suggest?

I have my own ideas, but just looking to get feedback from others before I make up my mind...

T3 would be good.


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I just installed the S20G and I gotta say, it's a great street turbo. The T3 is too small. Look at my post from last Sunday... it has comparison pics of the T3, 16G, 20G all side-by-side.

Originally posted by dougie2
I just installed the S20G and I gotta say, it's a great street turbo. The T3 is too small. Look at my post from last Sunday... it has comparison pics of the T3, 16G, 20G all side-by-side.

Ummm... you can't really make a generic statement like T3 is too small...lol, there be many many diff t3's...
Was looking more for an idea of what size of T3/t04 to get... ;)

im saving for either a t61 or a gt30 dual ball bearing. a nicely sized t04 would be sick though for your 2.4L. whats your power goals? i'll find you a a nice turbo that will spool at whatever rpm you want, just lemme know. hey man PM me...im SO sold on megasquirt you gotta tell me more about it and how i can get it hooked up on my car
_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

Originally posted by turbo8u
im saving for either a t61 or a gt30 dual ball bearing. a nicely sized t04 would be sick though for your 2.4L. whats your power goals? i'll find you a a nice turbo that will spool at whatever rpm you want, just lemme know. hey man PM me...im SO sold on megasquirt you gotta tell me more about it and how i can get it hooked up on my car _________ 96 talon esi-t san clemente, ca as needles of ice are the ill winds' talons the coldest of shadows they seep unto the bone silent souls leave .308 holes

Well actually right now I'm gonna build another 2.0... I wanna see what I can get from a 2.0 before I go 2.4... plus I don't feel like having to figure out the 2.4 unknows yet...lol

So I'm looking for a nice turbo for the 2.0, about 20G size, looking for around 400 HP, and gonna be running over 20psi... so that should give you an idea...

There's a few interesting looking t3 turbos on ebay... hmmm.

As for the Megasquirt... damn thing rocks... I'll get my writeup done...

Originally posted by MrSlick
Well actually right now I'm gonna build another 2.0... I wanna see what I can get from a 2.0 before I go 2.4... plus I don't feel like having to figure out the 2.4 unknows yet...lol So I'm looking for a nice turbo for the 2.0, about 20G size, looking for around 400 HP, and gonna be running over 20psi... so that should give you an idea... There's a few interesting looking t3 turbos on ebay... hmmm. As for the Megasquirt... damn thing rocks... I'll get my writeup done...

2.0? wtf?

a 20g is a good turbo, spools fast, bolts right up with the convenient hahn manifold and will definately support 400hp.

after reading megasquirts page im SO LOST it seems RIDICULOUSLY hard to set that shit up!!! how did you do it? wanna sell me what i need? ;) ;)



_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

Originally posted by turbo8u

Originally posted by MrSlick Well actually right now I'm gonna build another 2.0... I wanna see what I can get from a 2.0 before I go 2.4... plus I don't feel like having to figure out the 2.4 unknows yet...lol So I'm looking for a nice turbo for the 2.0, about 20G size, looking for around 400 HP, and gonna be running over 20psi... so that should give you an idea... There's a few interesting looking t3 turbos on ebay... hmmm. As for the Megasquirt... damn thing rocks... I'll get my writeup done...

2.0? wtf? a 20g is a good turbo, spools fast, bolts right up with the convenient hahn manifold and will definately support 400hp. after reading megasquirts page im SO LOST it seems RIDICULOUSLY hard to set that shit up!!! how did you do it? wanna sell me what i need? ;) ;) _________ 96 talon esi-t san clemente, ca as needles of ice are the ill winds' talons the coldest of shadows they seep unto the bone silent souls leave .308 holes

Yeah going 2.0 again for now... I'll still build a 2.4 on the side though...lol
2.0 has it's advantages... namelly the fact that I just got another 2.0 motor to use for free... haha. Plus I plan on making more power from the 2.0 than the srt pistons will take... some of the neon boys are finding that the srt-4 internals dont like over 450hp reliably... mostly because of the pistons. Plus the fact that the srt-4 pistons only come in stock bore... means you have to find a real nice block or worry about clearance...

So any recommendations on the turbo then bro?

yea i know what you're saying about the 450hp on stock srt internals, that is just because of the pistons though. CP's or JE's are good for that though, and with JE's they work with stock rod's. the old turbo 2.5 rods are actually stronger i think too, i found a pretty sick deal on some of those. 2 liter is nice for sure but it'll just take more boost to get as much hp as with more displacement obviously. i'd just go with a t04 of some kind with your choice of turbine/compressor configuration. or hahn 20g will work wonders too. even a 25g would be sweet imo. another thing to think about for around say, 22psi full boost...a gt25, its a nice ass ball bearing turbo and will support 440hp, .82 a/r
_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

How's this one look:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33742&item=2475526523&rd=1

?

ehhh....kinda small, thats a sick ass street turbo and would spool fast but i dunno about 400+ whp with it



2.2 pressure ratio is 19psi, thats about 76% efficiency
_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

Not a bad price though...
What would you recommend then my friend?

I'm just a lot more familiar with the mitsu turbos, havent used many T3 style turbos...lol

Show me the money...

you could always get a turbo like mine if you wanted to blow your motor up! :thumbsup

hehe.. 1.00 A/R compressor and 1.15 A/R turbine on a i have no idea what model Garrett.. i'm not sure a 2.0L motor could spool it though.

does anyone know what turbo the old nissan Pulsar's used? my dad had nothing but good things to say about the one he had.

PTE SC-50 It's a T3/T04E with a 50 trim compressor wheel, and different choices on the exhaust side. Exile Racing has them for $800. If you already have a manifold made for a Mitsubishi style turbo, they also make the SCM-50 which will bolt right up. I've seen it put down 378whp on an awd car, so 400whp on yours shouldn't be a problem. I am probably going with this turbo as well. I was thinking Evo3 16G, but I changed my mind. It spools pretty quick too, my friend that has it on his awd, with 272/272 cams and 8.5:1 compression hits 24-26psi by 3500rpms.

alright well lets figure this out...this is LONG as shit, but im bored...so bear with me. now, this is mostly approximate, but something to go off.

to choose a turbo, you need to first know how much cfm's of air it digests at redline. formula for a 4 stroke engine:

(CID x RPM)÷3456 = CFM

lets input some 2gnt data, 121.8 cu in at 7250rpm

(121.8 x 7250)÷3456 = ~255CFM

the engine will flow ~255CFM assuming 100% VE, lets assume a 85% VE for a 420a engine, so the formula now looks like this:

(CID x RPM x VE%)÷3456 = CFM

or for our application:

(121.8 x 7250 x 0.85)÷2456 = ~217CFM

so a 420a 2 liter at 7250 rpm sees about ~217CFM assuming a 85%VE, this is the first thing we need to know when choosing a turbo. heres some other factors

pressure ratio (on a compressor map)-
(desired boost psi +14.7 psi) ÷ 14.7 = pressure ratio

temperature rise-

compressor will obviously raise the temp of the incoming air as it becomes compressed, as temp increases so does the volume of air

t2 = t1 (p2÷p1)^0.283

t2 = outlet temp *R
t1 = inlet temp *R
P1 = inlet pressure, absolute
p2 = outlet pressure, absolute
*R = *F + 460

so i assume intake air about say, 65* and you said you want like 20-21psi boost, so here we go:

t1 = 65 + 460 = 525 *R

p1 is obviously atmospheric (or whatever elevation you are) p2 will be our boost pressure, 21psi. to figure outlet pressure, add boost to your atmospheric pressure, so:

p2 = 14.7 + 21 = 35.7 psi

now we have everything we need to figure ideal outlet temp, now we plug it all in to find the last factor, outlet temp...or t2, here we go:

t1 = 525 *R
p1 = 14.7
p2 = 35.7

so:
t2 = 525 (35.7÷14.7)^0.283 = 675 *R or 214 *F outlet temp, this is an ideal temp rise of 149*F, if the compressor had 100% adiabatic (sp?) efficiency (no gain or loss of heat) actual temp rise will def be higher.

usual compressor adiabatic efficiency is somewhere between 60-75%, so heres another formula:

(ideal outlet temp rise) ÷ (adiabatic efficiency) = (actual outlet temperature rise)

lets assume a 70% efficiency:

149 ÷ 0.7 = 212 *F actual outlet temp

desnsity ratio-

to compare inlet to outlet airflow we gotta know tyhe density ratio too (as air is heated becomes less dense, this increases volume) heres another formula

(inlet *R ÷ outlet *R) x (outlet pressure ÷ inlet pressure = density ratio

so here we go:

(525 ÷ 675) x (35.7 ÷ 14.7) = 1.89 density ratio

compressor inlet airflow-

using ALL ^^^^ info you can figure out the actual inlet flow in CFM, another formula:

outlet CFM x density ratio = inlet CFM

so ours would look like this:

217 CFM x 1.37 = 297.29 CFM inlet air flow

thats about a 37% increase in airflow, so about 37% increase in power. compressor maps are in lb/min, multiply CFM by .069 to convert CFM to lbs/min

297.3 CFM x 0.069 = 20.5 lb/min (that is NOTHING for a turbo)

now you can use these formulas with flow maps to select a compressor to match what you want.

now im not asure if you can do it this way or not, but i'll see if this makes sense...

140CHP = ~217CFM and you want to make about say, 450CHP...thats a 215% increase in airflow at 7250, approximately of course. 683.55 cfm or about 47 lb/min


hopefully i helped you learn a little more about turbo sizing and :) someone, anyone, correct me if i messed up or if im confused on anything, i might have messed up somewhere i dunno but is seemd about right

well looky what we have here ;) big t04



looking at this compressor map, 16psi (or 2.0 pressure ratio) will flow about 47lb/min of air


hope i maybe helped some :thumbsup
_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

Originally posted by MrSlick
Ummm... you can't really make a generic statement like T3 is too small...lol, there be many many diff t3's...

Sure I can make that statement. I know a lot about these turbos and have personal experience using them. Buy the biggest T3 you can get find and it'll still be too small for your goals. Any given T3, regardless of A/R measurement, trim, CHRA type and boost level will net you no more than a 350HP return.

Originally posted by MrSlick
Was looking more for an idea of what size of T3/t04 to get... ;)

Well, a T3/T4 is not the same as a T3 that you asked about. Do a little research about Garrett turbos and study some of it's compressor maps. Plot efficiency data from you particular engine and choose the one that'll work best for you. Consider one with a turbine housing A/R of 0.63 and compressor housing A/R of 0.60 or so. The 50 trim compressor wheel works very well too.

If you need help finding the most efficient turbo for you setup, e-mail me with your engine setup and overall performance goal and I'll crunch the numbers.

57 trim small? your nuts..a 57trim dwarfs a 20g...57trim with a .63 stage 2 turbine is a sick turbo..fast spooling and retarted amounts of power..i know i had one...will DEFFINATLY support 400+ hp....amd do it at lower boost levels than a 20g..

Originally posted by dougie2

Originally posted by MrSlick Ummm... you can't really make a generic statement like T3 is too small...lol, there be many many diff t3's...

Sure I can make that statement. I know a lot about these turbos and have personal experience using them. Buy the biggest T3 you can get find and it'll still be too small for your goals. Any given T3, regardless of A/R measurement, trim, CHRA type and boost level will net you no more than a 350HP return.

Originally posted by MrSlick Was looking more for an idea of what size of T3/t04 to get... ;)

Well, a T3/T4 is not the same as a T3 that you asked about. Do a little research about Garrett turbos and study some of it's compressor maps. Plot efficiency data from you particular engine and choose the one that'll work best for you. Consider one with a turbine housing A/R of 0.63 and compressor housing A/R of 0.60 or so. The 50 trim compressor wheel works very well too. If you need help finding the most efficient turbo for you setup, e-mail me with your engine setup and overall performance goal and I'll crunch the numbers.

Well Ok so I asn't being very honest earlier... I do know quite a bit about t3 or t3 style turbos... I was more looking for other peoples opinions... and experiences...

Lee.

Why stick with old technology, look at the wheel on the old T series compared to a GT wheel.

Garrett makes non BB GT turbos, we offer the SC61 turbo from Precision which uses the GT exhaust wheel. If you want good spool speed and lots of power potential look at the Garrett lineup. My 2.5 Avenger will be running a GT32e, nothing insane but good to over 520hp.

Originally posted by SANDMAN
Why stick with old technology, look at the wheel on the old T series compared to a GT wheel. Garrett makes non BB GT turbos, we offer the SC61 turbo from Precision which uses the GT exhaust wheel. If you want good spool speed and lots of power potential look at the Garrett lineup. My 2.5 Avenger will be running a GT32e, nothing insane but good to over 520hp.

ive been looking into going with a gt30 dual ball bearing myself, actually...i cant really decide but this one tickles my fancy like no other :) you sell a good array of gt series turbos?



_________
96 talon esi-t
san clemente, ca


as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

silent souls leave .308 holes

here is the compressor map from the turbo i want to get :D

http://www.turbobygarrett.com/turbobygarrett/images/turbo_kits/GTP38R%20comp%20map.pdf