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Discussion Starter #1
I decided last night to reinstall my stock air box, and remove the BW. I wish somebody has AutoTap #'s for 02 with only modified intake installed. I do not see how Halltech and BW can sell these bad boys alone without upgraded injectors and MAFT it should be the whole package or nothing. If they are so lean at WOT and injectors are at 95% then 02's can start having valve problems(longterm) etc. Sorry I keep bring this up, but I just do not want to see ruined motors. Another thing that I thought which I could be way wrong so please help: If you go to larger injestors for WOT won't the motor run rich at idle and city driving. The pcm does not know it has larger injectors so it tells the injectors to spray and your just cruising around town pig rich the whole time the pcm is thinking stock injectors and you have actually increased the volume alot. Am I stupid or does this sound kinda correct. I can take huge flames.
 

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Your question has a long and a short answer. First the long answer.

I installed several mods that effected the AFR, the Halltech TRIC/Cobra, a TB heater bypass, and I "lost" my cats with just an X-pipe back to the mufflers.

I can't say which mod produced how much of the lean condition, but the total was 18% lean(!), that is, 18% extra fuel was required to get back to stochemetric.

This much extra fuel runs the stock injectors very near their limit (80% duty cycle is supposed to be the max). Because of this, I changed to SVO 30# injectors. (Other people sell similar injectors for 2-3 times the price, but these are race quality and work just as well for about $260.)

It turned out on my car that with the SVO injectors, the LTFTs were almost back to zero (the ideal). This was **just an accident** -- it could have been one way or the other. But I also got an EASE PCM scanner to determine this, and also installed a MAFT to allow me to fine tune the AFR.

Many of our "C5 tuners" apparently thought that they could sell their mods, and that the PCM would "re-learn" to compensate and add fuel to produce the extra HP. But because the GM algorithm in the PCM was not designed to compensate for mods (and there is no practical way I know of to modify the GM code), you leave a lot of power on the table if your LTFTs are not very near zero.

Halltech, for one, now says that a combination of larger injectors and a MAFT or (what he calls) an "AFR calibrator" (or something like that) is required to make his packages produce all the HP they should. He is correct.

This PCM tuning is a recent development, probably pioneered by John Rovner at <www.teamzr1.com>, a former GM test engineer. A number of tuners are now working on trying to understand what goes on in this complicated GM PCM. But GM holds the source code to this software very close, and I have seen very little discussion of its algorithms in the open literature. (Although I am not an "expert" in this area.)

It is rumored that the group that produced the "LT1-Edit" software is about to release an "LS1-edit" version for LS1/6s. This would allow one to re-flash the code/values in the EEPROM in the PCM. However, without access to the GM source code, this won't solve the problem of exactly what values to flash. There is a lot of reverse engineering going on to try to figure all this out, but no amount of reverse engineering is a substitute for access to the real source code.

So, the *short* answer to your question is that a MAFT, PCM scanner, and maybe larger injectors is the solution to your mods problem.
 

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Discussion Starter #3
Thanks for the long and short, I am slowly starting to understand how the pcm a/f works, because of the members in this forum. It sounds like the best thing to do 1st. for a 02 is purchase a scan tool or software.
 

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JimGreen said:
Halltech, for one, now says that a combination of larger injectors and a MAFT or (what he calls) an "AFR calibrator" (or something like that) is required to make his packages produce all the HP they should. He is correct.

WRONG . Please if your going to give info, get it right, a lot of guys read these threads and they want answers not BS!! Your comment might be true for his T-1 "PACKAGE" but not just for his T-1!! Here is his Quote "We have over 100 T-1 Intakes sold, with maybe three that have reported the code. It can be reset from the driver's seat in 1 minute, and so far they have not returned. You should have the same 16 RWHP we got, with no other changes to your Z06. We never saw a lean code, and have only heard of two customers getting them. The idle relearn process described in our instructions, usually solves the code problem since that procedure resets the butterfly position of the throttle body.

You will never see a rich code, but if you do, it will not be the result of our T-1 intake.
Are you saying he is lying about his own product, or just interested in slamming him again. :roll:
 

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I'd suggest the EASE scanner. John Rovner over at <www.teamzr1.com> can get you one at a "team" discount from EASE. John does this as a favor to the team members, he doesn't make anything from it.

Join the "Team", membership is free. Subscribe to their e-mail list. John ("JR") is the source of all I know about this PCM stuff. He is a really nice guy. He has been extremely kind in running analysis of my PCM scans and recommending changes. He also posts a lot of technical info about GM stuff that I find very useful.
 

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2002BlackZ06,

What Jim Hall said was "We have over 100 T-1 Intakes sold, with maybe three that have reported the (rich) code."

I didn't say I had a rich code. The rich code is not set until you get the LTFTs greater than +25% (= 25% lean). I was running +18% (= 18% lean). Therefore I didn't get any codes.

What I did say was that mods which significantly increase air flow (more air+fuel = more HP) will cause the LTFTs to go a long way away from zero (like mine went +18%). Even if they don't set codes, they cause sifnificant HP to be left on the table. Jim Hall verifies this by now recommending larger injectors and his "AFR calibrator" (I think that's what he calls it).

Finally, I resent you suggesting that I am "saying he is lying about his own product, or just interested in slamming him again." First, I have never "slammed" Jim Hall. I did not do so in my post. I have never accused anyone of "lying about his product". I suggest you read my comments more carefully before posting such accusations, particularly on a public forum.
 

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Jim, you keep saying That Halltech is now agreeing that larger injectors and other things are needed to make his T-1 work better. Again I say you are getting mixed up with his T-1 "package" and just his T-1 intake. Show me where he says that his T-1 intake needs all these extras. I have already shown you where he says they don't. As for saying you are calling Jim a liar I appologize. I have just seen you pop up on his threads, countering a lot of stuff he was saying.
 

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Jim, you asked:
Your quote to Halltech:It doesn't make any sense at all. (Actually, it sounds to me like BS.)
B.S. quite often means your talking crap, or you are a liar.

Your quote to Jim:All this sounds to me like you are trying to bamboozle the readers of this forum with double-talk, making them think you have some "secret" HP to sell. Tell me it's not so. Come clean.

This statement sounds like you are saying he his misleading his cutomers, or pulling the wool over their eyes or lying to them.

Like I said Jim, you asked.
 

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2002blackZ06,

Your apology is accepted.

You may be correct that I have confused the T-1 "intake" vs. the T-1 "package". I wasn't aware that there were two. I was commenting on Jim's comments on his "T-1", in which he recommended both larger injectors and some way to tune the LTFTs as the only way to get the full 30+ rwhp gain. I wholehartedly agree with Jim on this, that just adding the intake will not produce the full HP gain. That has been my experience too.

Can you add just an intake and realize *some* HP gain? Yes. Are you leaving some HP on the table if you do that? Yes again.

Finally, by "I have just seen you pop up on his (Jim Hall's) threads, countering a lot of stuff he was saying". I didn't think a thread on this forum **belonged to anybody**? I thought threads were here so *anyone* could post comments?

Do you mean that I post *questions* about what he has said and *challenge* some of his statements of fact? I thought that was what forums of this sort were for. How else are you going to get the facts straightened out? And my father once told me, "Among gentelmen there is always room for a difference of opinion".
 

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Installing the T1C Intake

I have just ordered the T1C from Halltech. I have read all of the threads that I could find concerning the AFR with the increased air flow. I did not see a clear answer. My question is quite simple.

"If I install the T1C, with no other engine modifications, am I risking engine damage under any operating conditions as a result of the additional air flow and RWHP provided by the T1C?"

I deal with the O2 values and rich and lean fuel conditions on my 20th Anniversary Turbo Trans AM on a regular basis. We monitor O2's, timing, and fuel presure on each run so that we get the proper combination of boost, fuel mixture, and boost on each run without blowing the head gaskets. We also modify the PCM chips for injector upgrades, etc. The lean / rich issues that I am seeing discussed here regarding the LS6 don't seem to relate to the issues we face with the turbo cars. Almost all of the members of my F-Body club with LS1 engines upgrade the intake as soon as they buy the car. These guys for the most part run with scanner software on a lap top at the strip and I don't recall any of them having a rich /lean issue. Is the PCM on the ZO6 less capable that the PCM on the Trans Am and Camaro?
 

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Ok Jim, this is my last response and I am going to put it to rest. There is nothing wrong with differences of opinion, discussions etc. As I showed in one of my previous replies to you. You were suggesting he was, lets say "Not being truthful, to his customers". That is where, I think you were not using discression in your wording. that's all I am saying. :cheers:
 

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Z06ROX,

I think there is starting to be a lot more information out there regarding bolt on mods for the Z06. Bottom line is, as you mentioned, the first stop should be to buy software, auto-tap or whatever, so you can see what your mods are doing.

I have the T-1 Sidewinder installed and I also have the TRIC which I haven't put on yet. Initially I installed the T-1 with the stock '01 MAF and everything was fine. Since I don't have a scanner all I can say is about my air/Fuel ratio is that my MPG went up about 3MPG overall after installing the T-1. I can't say anything about HP since I've never put my car on a Dyno.

I've read a lot of posts where guys have taken the screen out of the MAF in the '01 to help it breathe better. I didn't want to do that so I bought an '02 MAF from another forum member. Since installing the '02 MAF with the T-1, my MPG have gone done about 2 MPG (still above what I was getting stock) but my idle is a bit higher now and I have some surging when I put the clutch in when coming to a stop.

This could be because I do not have the filter on perfectly, although I have checked it 3 times now and it seems okay.

But, like you, what I would really like to know is where my fuel air ratio really is now. Possibly with a MAFT or AFR calibrator I could tune it in better or maybe not.

So like you I've thought about going backwards. But at the same time, I think my next mod will be auto-tap or similiar software and a MAFT or AFR calibrator.

Last, I have never received any codes after installing the T-1 with '01 MAF or '02 MAF.

In fact the only code I have is 60 B0516 H - Speedometer reading malfunction. Which I'm keeping because if I ever get stopped I'll blame the speedo and let the judge sort it out :)
 

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I'm glad this thread is back to it's original subject.

Dfunde01, you are asking about "Am I risking engine damage under any operating conditions as a result of the additional air flow and RWHP provided by the T1C?"

Again, I am not an "expert". But I think the issues of PCM tuning we are discussing is about *how to get the maximum HP from a mod*. I don't believe any mods we do on a normally aspirated LS6 can cause "engine damage", like you might get with too much boost pressure on a turbocharged car. On a normally aspirated LS6 motor, the PCM will "learn" LTFTs back to near stochemetric. Its just that at WOT, the PCM algorithm doesn't produce the best results if your LTFTs are +20%.

I'm not familiar with how you tune a turbocharged Trans-Am. The Trans-Am PCM must have code that deals with AFRs during turbo boost, which code is not present in the LS6 PCM.
 

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T!C

Jim,

You are correct in your assumption that the TTA PCM contains additional code to deal with boost and AFR. I am just learning the process and still depend on the Buick GN and TTA Guru's that I know to fine tune my chips for me.

From your answer am I correct in assuming that I will gain 16 RWHP from the T1C with no negative effects. I understand that I am leaving significant HP on the table by not moding the injectors, TB, etc. I plan to use the ZO6 as my play car for cruising and track days at Little Talladega and Road Atlanta and don't plan any other performance mods.

Thanks,

Dave
 

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dfunde01,

Personally, I have no experience with the T1C. But my similar experience with the TRIC and other mods mentioned above suggest that some real HP gains should be realized. I guess the only way to tell exactly how much *on your car* is to visit a dyno.

A bunch of people have installed similar mods from Halltech, Breathless, and other vendors without any problems of engine damage. (At least I assume that is the case, or we would certianly have heard about it.) If you are mostly going to do street driving, I think you will be OK.

To be on the safe side, If I were you, my next mod would be an OBD-II PCM scanner. I have the EASE, which I purchased through <www.teamzr1.com> at a discount for about $315. With that tool, you can tell exactly what your LTFTs are doing. You might ask the "expert", John Rovner, but if it were me, if my LTFTs were over 10-12% lean, I would get a MAFT or a MAFT plus larger injectors to zero them out. But that's just IMHO, and I am certianly *not* an expert, I'm just learning.

HTH, Jim
 

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Reversing the Z06 PCM

Guys,

most of you don't know who I am.. as I'm the new guy here
and I'm waiting for Rick D. to make my new Z06 appear :D

In "real life" I reverse ECU's for a living.. Mostly for Euro
cars like BMW's. As an "owner to be" I have every intention
of completely figuring out the Z06 PCM.

However, I don't have any intention of turning it into a business
because I remember what happened when I did that w/ BMWs
(It sort of took the fun out of it!)

So where do we stand.. I want to do it, and have the skills.

(The processor in our PCM (68332) is old hat for me)

I'd appreciate any leads on other "experts" as well as
a source for a spare PCM.

Of course, in a perfect world :cheers:
someone would already have downloads of the flash
on both the 01 and 02 Z06 PCM's.

:D

BTW, you are correct. you DONT just "change injectors" without
actually reprogramming the PCM to handle it. It's like teaching
a pig to sing.

FWIW, I'm the dude who figured out how to properly put larger
injectors on both OBD-I and OBD-II BMW's without "external
addon boxes" and I'll be more than happy to do it for the Z.

I mean, how complicated can it be :D :D :bang:

Jim
 

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hi Jim,

I know who you are! I bought a shark injector for my previously owned '97 M3. We look forward to your expertise and perhaps a shark for the Z? :D

john
 

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Jim Conforti,

Your post is like music to my ears. I'm also an old software hacker, but not on PCMs.

Please send an e-mail immediately to John Rovner <[email protected]>. He is beta testing the ECM software up-loader for LS1/6s (LS1-Edit?). He's a former GM test engineer. Everyting I know about PCMs I learned from John. I suspect that you two could help each other a lot.

As I understand it, the main problem is that GM does not publish the *source* code for our PCM. Thus it's a lot of reverse engineering to find out anything useful about it. You sound like you know how to reverse engineer this thing. Please e-mail John.

Thanks, Jim Green
<[email protected]>
 

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LOL

Actually I had just hit SEND on a message to him
when I saw your message.

On the Shark Injector.. it's possible that we can make it
work for the Z06..

Note however that I don't have any intention of going
directly commercial with the 'vette stuff.

If it works, I'll be more than happy to provide injectors to
the 'vette tuners out there to use (and owners of course)
but going "pro" always seems to take the enjoyment out
of your hobby.

I don't want to lose my enjoyment of a car I don't even
have yet

Jim

EB/Blk 02
(due to be built in early Feb)
 

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Jim,
Welcome to Z06vette.com:)
Like everyone else that had to wait, hopefully the forum will keep your z06 itch scratched for a while:D
Look forward to reading your posts on the Z06's PCM:cheers:
 
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