jeremym

iTrader: (3)

What boost can I run with a 98 pcm using HP tuners? I was going for 14psi but somebody said run 16psi to get more low end. This is a F1A or F1C with the SDCE tensioner on a 427 LS7.

SuperZ

iTrader: (2)

i ran 14 on my last setup and well see how I can on this new one

jeremym

iTrader: (3)

I was thinking of running 16psi

SuperZ

iTrader: (2)

yeah 16 would be fine

Photochop

iTrader: (74)

I've heard the 98 PCM will not support anything over a 2 bar map (14.7 psi), speed density or MAF

Jake@EPP

Correct with hpt it is 2bar, efi is only MAF i think.

98 guys need a dang bs3

phoenix

iTrader: (6)

are you serious.... i am plaing on running 18 psi, and i wanted to keep it stock pcm!
damn this project keeps geting more and more expensive
i thought 1 bar = 14.7 psi?

SuperZ

iTrader: (2)

does that really matter that much???
I ran 14/15 threw a mass air and ls1edit also a few years back

jeremym

iTrader: (3)

more info please! So can I get away with 15psi? If the 14.7 thing is true what happens if u try to run 15-16psi ?

GrandmasterCow

iTrader: (5)

I run 15 no problem

Jake@EPP

Yes it does, running a maf tune after it pegs is a band-aid. How do you think your pcm knows about airflow above the maf limit? It does not, you use the PE settings to try to offset it. If the belt slips you go rich, if your a turbo and over boost you lean out, not the correct way to tune. Aka Alpha-N (fuel x rpm dins), changes rapidly to altitude and weather changes.

With edit there was not a speed density style of tuning. You can always upgrade to a 99+ setup.

frcefed98

iTrader: (16)

As of monday i'll have Kyles (NA$TY-TA) old MAFT PRO on my 98. Its a nice lil piggy back that has realtime a/f tracking, 3-5 bar capability and is SD and tune on the fly if I remember right.

Be nice to just be able to turn up the boost and have the MAFT PRO automagically compensate.

Worked great for him, but he went bigtime and went full standalone.

Just another option for us 98 guys(technically any car with a MAF even LT1's)....and they sponsor the board

http://www.maftpro.com/tproinfo.shtml

J

jeremym

iTrader: (3)

so I can run 15 and be ok?

Jake@EPP

14.7 to be correct Its up to you if you want to shell for a standalone or other venues but it is doable without being correct, is it correct... no, but will it work... probably but no guarantees.

jeremym

iTrader: (3)

if this is true how do I get 14.5psi? I heard better heads will lower the psi because better effncy . Is that true?And I plan on running a 4inch e-b a/k&n air fliter. I heard people have seen more boost when they did that, is that true?so what psi pulley should I get if my ported fast and my heads will lower the boost and k&n might raise boost?the heads are 68cc chambers with 86 intake runners.

Sideways240sx

iTrader: (22)

Not really.. Stock mafs max out @ 512 g of air. That is usually low to mid 500 whp.. Most decent turbo setups do that around 7-10 psi. Anything over that is more or less a guess, as there is really no way to know how much air is going into motor. That is why people go SD.

with a 98 you can do a 2bar sd. Which will allow you to go to 14.7 psi, but you have to get the sd os, and a 2 bar map sensor. Easy enough just need a tuner that knows what he is doing.

the 00-02 pcm you can run a 3 bar map sensor and get to 28 ish psi on a ecu. There are people that have done the pcm swap.

It requires re pinning, but you dont really have to cut any wires. Then you have to flash a 02 chevy express van fuel segment to get the fuel gauge to work. I think that part has to be done in efi live, but this is nice, because in the past people would swap the ecu/cluster.

WHen you put a 00-02 ecu in all you loose is traction control, and on the 98's the low oil light.

Other options would be bs3, aem, or maf translater pro that joe had mentioned.


Chris

jeremym

iTrader: (3)

I will just run 14-14.5 psi. How hard is it to change the computer? And what year? How can I get the correct psi with my combo?

Sideways240sx

iTrader: (22)

You will have to let me know how this works out for you... I am very interested after seeing/reading about it.


Chris

Sideways240sx

iTrader: (22)

Most people try to get the 02 ecu. Try to get auto or manual for what ever you are. Or if your going with a glide/th400 or 350 you want a m6 ecu...

I have been told that people that have done it, and focus and work hard on it can do it in 1 hr or so. Id imaging it would take myself a couple hours.

102 wires need to be moved. If you dont have wiring diagrams for both cars id imagine it would be pretty hard.

I believe the easy way of doing the ecu swap is to get a 02 harness, 02 cluster, and 02 ecu. But that adds cost, and im not sure if its all works without any issues.

Chris

Jake@EPP

I had talked with a customer on this a while ago, it was in his best interest in going bigstuff 3. After adding up labor to re-pin the harness and the tune setup, he was getting into the territory of bigstuff. The car had a 4l80e so it needed controlled as well, it was also going to see 20psi in the near future so we figured the best way for him was the bigstuff 3.

We had looked at the TCI setup but it lacked alot in the interface and still didnt fix our tuning issue.

The bigstuff is installed and working with all factory gagues and sensors. The bs3 can be setup for multiple race type sensors if needed.