Hey guys... I too am a graduate of V6Z24.com :)... still an awesome site though!

Anyway, I have a pretty heavily modded 3.2T (was 3.1L)  but have some concerns and questions that i haven't really had answered by the J-body folk.

Here is my setup
3.2L Turbo (stock t-25 garrett)
255 lph in tank fuel pump
Stock Cavalier ECM and memcal

now we are tuning and we obviously have some timing/fuel issues.  We plan on using an MSD DIS-4 box to pull timing, and use an adjustable procharger FMU to compensate for fuel.  

I've been told that the stock TGP fuel injectors are no good after about 10 psi.  Is this true??  Do I need to upgrade?  Also, I was told that even though I've got a strong fuel pump, I should still throw in an inline pump or my in tank one will die on me sooner than expected.  Are these both true??

I have a forged bottom end and provided eveything is tuned we're expecting 330ish crank HP.  That's a biig if though seeing as how we can't seem to figure out our tuning issues.

So....
#1) Do I need to upgrade my injectors and what do you guys suggest.  Also where to buy em would be good ;)
#2) Do I need an inline fuel pump now?
#3) Do you guys have any better tuning suggestions other than the MSD box and an FMU?

ANY help with this would be REALLY helpful guys.  I know I'm new to the boards but we've been on this project for almost 4 years now and it's about time to finally get this DONE!  

Any Thoughts?

Dave

Hey Dave

That Walbro 255 Pump will be fine for your engine.....im running the same one.

is this car a 5-speed or automatic???

as for computer tuning if your running the stock cavi chip, i suggest geting a modified TGP memcal and with www.gmpcm.com you can tune it to your liking.

was this a TGP engine you originally used or are you just using a T-25?

anyway need some more info  :)

Get rid of the crap and tune that chip yourself.  No MSD box, no FMU, just the chip.  The injector thing is a big debate, there are 1 people (hey Jud!) using big injectors w/ little to no problem on stock code.  Then there are other people (hey Davie) having problems w/ 24# injectors.  So you'll get different answers on that one.  If you want to go the mechanical way (FMU and box) Jud is probably your man.  If you want to go the tuning route, hit up the tuning section and the link Davis gave you up top and that should get you going.

One more thing, I'll start the flaming:

Why the hell would you keep a T2-small w/ an engine modded like that?  You'll never reach the potential of a forged bottom w/ a T25.  Unless it's like a 2871 or something, in which case forged is overkill, but w/ a 330 goal I think it's safe to say it's not a stock T25.  All in good fun, and welcome aboard. :D

That is something that never crossed my mind to run 2 fuel pumps. So others are using the in tank along with a walbro :?: LOng live the T-25!

Hey guys, thanks for the info thus far!!

To answer some of your questions...
it is a 3 speed automatic with a shift kit
this was a 3.1 turbo from a TGP that we basically tore apart and built up.

And yes, after doing A LOT of research, i'm going to have to agree that I should get rid of the FMU and MSD box and have chip burned.  

And the reason we are keeping the small turbo is mainly because of the cost/power ratio so to speak.  Since we can't run over 14psi b/c of the weak heads/gaskets/tranny and other weak points we decided to keep the t25.  Like i said before... the v6z24 board didn't have too many TGP experts and in retrospect the forged bottom end might have been overkill :(:(:( but I was told that anything over 8psi would have popped a stock piston or 2.  

Oh yeah, and any ideas how much timing I should be pulling when I burn a chip?  I'm assuming 1.5-2 degrees/pound of boost?  Sound about right?? Anything more specific would help though ;)  

THANKS GUYS!... I feel right at home :)

oh yeah, and who are the chip burning people I should contact?

Quote from: ZoTurboAnd the reason we are keeping the small turbo is mainly because of the cost/power ratio so to speak.  Since we can't run over 14psi b/c of the weak heads/gaskets/tranny and other weak points we decided to keep the t25.  Like i said before... the v6z24 board didn't have too many TGP experts and in retrospect the forged bottom end might have been overkill :(:(:( but I was told that anything over 8psi would have popped a stock piston or 2.  

Just because you can't run over 14psi doesn't mean you should keep the T25.  14psi on a T25 is like 10psi (or maybe less) on a 2871R or something like that.  The T25 is very inefficient and really sucks.  You'd make WAY more power with a better turbo.  

You can run 14psi just fine on a stock bottom end.  I wouldn't have touched it if the engine ran fine.  I run 12psi daily on pump gas (premium of course) on my almost 110k TGP engine and this is pulling the weight of a w-body...no problems at all whatsoever. (so do many others on here)  The bottom end takes it and I really beat the piss out of it.  I used to run 12psi daily in my STE until I did the engine work and don't have large enough injectors anymore and it had no problems, and my dad has been running 11psi daily in his TGP for the last 35k miles or so with absolutely no problems, besides the fact that its starting to get some higher miles on it and the rings are worn so it smokes under full boost.

Shawn

so seeing as how this boost is 'less powerful' are you saying I can safely crank it higher simply b/c it's a T25??

Dave

Well I would think 35lbs injectors or so would be ideal for your power goal just to be on the safe side. 270hp is about all the 22lbs have at 92% DC and 60psi of fuel at 10psi of boost, and BSFC of .55(according to Jeffs fuel rise and DC.)
Hit summit or ebay for a score of them. I got mine from a 98 GTP..(some slight mods to the GTP injectors is needed to get them to work).

That pump you have is good for your goal. Porting the fuel rail like I did won't hurt though. (pic soon...don't know how this mod would help under 300hp)

On tunning...a reprogrammed TGP code on your car would do wonders compared to all those gizmos combined. Search the Chip tunning section for some hitnts and know how. and going to syty.net won't hurt to see some of their tunning advice and pointers.

AS far as the T25..its flow rating is about 260hp at around a PR of 2. So the 3.2 would be about 250-280hp tops with a good IC (bringing the desity ratio to pressure ratio values)and free flowing exhaust. An upgrade is needed for higher goals. BTW..is your engine just a overbore 3.1..and nothing more?...IE..like ported heads, cam, ported intake. Maybe your only limited to 14psi at lower rpms and 8-4psi at higher rpms with the t25. BTW..I was pushing 10psi WITH NO COOLER on a ported, camed engine on the t-tinywinnie. NO problems with engine meltdown. Only time you need to worry about broken parts is when you run lean, over rev, have too much boost at tooo low of rpm ,or too much spark advance.

The heads are fine..I don't know how you got the idea they are weak. If you overheat them..then yes..they will fail just like any aluminum head would. Gaskets are good. I hear the "Detroit" Stock gasket is better than the Felpro. I say gaskets are good for 350hp and would need wire ring beyond 300hp for more duability. Contace Jeff M. on wire ring specs. You could also get the copper gaskets..but require tight tolerances to head and block.

I can truely say that the 3t40 thats in your cavi is a WEAK SUCK if you don't have high performance clutches and band. The shift kit (transgo or superior?)will save your hide for right now. I have a fully built tranny that "Should" hold my goal of 300-400hp. This includes high performanche clutches, high energy band, shift kit, buillet pumpshaft, buillet boost accumulator, and some stiffen accumulators ,and some other secret wepons  8) . Don't waste your $$ on a 5spd just yet. This trans can surpass the 5spd and some change if done right.

The spark retard is idealy 1.5-2*. But every rpm and powerband is different..might be .5* at one point and 4* at another. Tunning is golden.

Nuff said. Take notes..and SAVE AS  :lol: .

haha, thanks man... 'save as' indeed  :lol:

www.jcob2.com
click the project zoturbo link on the left.  that'll give you an idea of what we are dealing with.  I REAALLLY wish I woulda known about this site when we started this project :( lotta goodies here that i didn't know b4.

So provided I get some 36lb injectors AND a chip tuning is there any reason I can't crank the boost a little higher?... say 18-20?

Dave

Quote from: ZoTurboso seeing as how this boost is 'less powerful' are you saying I can safely crank it higher simply b/c it's a T25??

Dave

No, I'm saying that its so small an inefficient, that even though its making lets say 14psi, its like only having 10psi on another turbo.  But the air at 14psi is still really really hot with the T25 so you can't go higher boost because its really inefficient.  I would definately not run 18-20psi...you'll probably go slower and blow something up in the process.  The tiny T25 is WAY too inefficient at those boost levels.  You probably wouldn't want to go much over 12psi with it.

Shawn

i belive the T25 Chokes at 14-15 PSI

man where were you guys 3 years ago when I started this thing! :( coulda spent the money MUCH better!

Well I wrote this yesterday but never sent it. :oops:

You guys Jay, Shawn, TurboGTU pretty mush hit it on the head accept for a couple of things that I'll coment on. :roll:

Yesterday
Welcome Dave,

No matter if your new people will still answer your questions.

I don't like to be the bearer of bad news but your T25 to small won't get you near 330 RWH. After 10 or 11# the air turns to shit. It?s just spinning too fast. Its good for maybe 240 HP. If your looking for those kind of numbers go to the GT series (almost bolt on) or T3 style. The GT28 at 5# is faster than the T25 at any # so you can imagen what it?s like at 10# or more.
#1
To get 240 HP your TGP injectors will be at 100 duty cycle. So a litter bigger would help. With a GT turbo you will be in the 30 36# range.
#2
As Dave said that pump should be fine. Is it the HP?
#3
If you have the Dis 4 use it. Is your FMU a RRFMU? If not get one. You will be up and running 6 mo before you learn to reprogram chips.

Today
As long as you don?t lean out you won?t hurt heads or pistons. Pistons will go long before the heads but if you don?t get it shut down in a hurry you will take the head out to. :cry: Been there done that to many times.

I pull out from 3 to 5* with the Dis 4 depending on boost. With the T25 I don?t think you will ever have to pull timing especially if you have the TG chip. He pulls out a lot of timing. The MSD is one heck of an enhancement to the stock ignition. You also get
2 rev limits plus timing retard.

Best of both worlds is learn to program the chip and have the gizmos to tune with. You can?t reprogram the chip at the strip ( well I guess you could but kind of im-practical)  but you can alter fuel and retard and boost with what you have. Even if I was chip tuning I would have the gizmos. (gizmos, I like that word cause I have a bunch of them) :D  At one of my strips it goes from 90+ to 70-*in hours and the fuel adjustment is crucial. Being able to take 30# injectors to 36# injectors is a real PLUS although I think I have the 30?s maxed out.

You can disconnect your boost control and you will never be able to use 36# injectors with the T25. Your noes will hit the stering wheel the first time you punch it.

Quote from: ZoTurboman where were you guys 3 years ago when I started this thing! :( coulda spent the money MUCH better!

Right here although we didn?t have the knowledge we have now. There has been a ton of data pumped into this and the other website in the last three years.

Quote from: Prospeederi belive the T25 Chokes at 14-15 PSI

You are better off to limit it to around 10 to 11# unless you want to go slower.

Quote from: dbtk2

Quote from: ZoTurboso seeing as how this boost is 'less powerful' are you saying I can safely crank it higher simply b/c it's a T25??

Dave

No, I'm saying that its so small an inefficient, that even though its making lets say 14psi, its like only having 10psi on another turbo.  But the air at 14psi is still really really hot with the T25 so you can't go higher boost because its really inefficient.  I would definately not run 18-20psi...you'll probably go slower and blow something up in the process.  The tiny T25 is WAY too inefficient at those boost levels.  You probably wouldn't want to go much over 12psi with it.

Shawn

I never could ge more than 16# with my T25, that?s when I learned that lower was beter.

And Dave if you can get the T25 to 18 to 20# PLEASE let me know how you did it. Might be possible on a 1.8 lt 4 banger.

Quote from: TurboGTUHit summit or ebay for a score of them. I got mine from a 98 GTP..(some slight mods to the GTP injectors is needed to get them to work).

What did you do to the injectors and where did you find out what to do :?:


Well I am tired, past this old mans bed time. :P

Good job guys jumping in with a newbe, wish we had more that are trying to tune. i am tired of fixing the brake light switch. :cry:

Hay Davis are you running ok yet? Pm me if you want to fix it. :wink:

Dave hope you figure out what you want to do. Good luck

Believe me  am not bashing  you chip tuners. I apalud your progress.
II am just of the old school, air + fuel + timing make a motor go. After running a C/alterd a A/ alterted , a DD dragster, an A/G drasgter I have just reverted to the GIZMOS. they seem to work well for me. :D  Seeing I have the fastes TGP on th planet. :D

Well I think I an done rattling.


Jud

sleeperred90tgp-

QuoteWhat did you do to the injectors and where did you find out what to do  

I just made new slots on the top of the injector to lower them into the lower intake as they were too short. They are perfectly sectioned and pressure tested leak free. I did get some notes from one of your old post about Lt1 or ls1 injectors needing to be lowered (remembered injectors looked the same)..was it you?? Cain't remmeber.  8) See..I do take notes :wink: .


But what fuel pressure and BSFC are you using for TGP injectors to be maxed at 240? I keep getting about 1 to 1 fuel rise and turbochaged engines using a BSFC of .55 ..or is it because you rose the BSFC to .58 or .6?

well seeing as how the entire world recommends a better turbo... any recommendations?  I noticed you listed 2 in your post but keep in mind that I don't know what those mean... I'M NEW TO THE TURBO/TGP WORLD! :)  thanks SOOOOOOO much for all your help guys!  You have no idea how long it would have taken me to figure this crapp out on my own on the v6z24 boards.  

So for now... I need to get some 36 lb injectors, and MSD box, a chip tuning, and a better turbo... sigh... better hit the lotto soon ;)

Dave