CantKeepemhooked

This thread has ALOT of useful info for FI newbies. Im goign to wrap my exhaust once i get everything back together.

RooRnZ28

iTrader: (14)

damn, so is it bad to wrap the exhaust and not get it re-tuned?

CantKeepemhooked

from what i read the boost builds faster at lower RPMS with a wrapped exhaust. so u might need a slight re-tune to really gain the full potential of the exhaust being wrapped.

JD_Z28

iTrader: (19)

I think it depends a lot on how your cars is already tuned within those rpms that you now building boost in.

koolaid_kid

iTrader: (21)

If I may paraphrase, what you are saying is that if you have a perfect (well, within reason) tune prior to wrapping the exhaust, then it may be O.K. to still run the car without retuning? I wonder how much of a change is needed, or how far off the tune will be when the wrapping is complete.
Just trying to understand the impact of wrapping the exhaust and not dialing in the tune afterwards.

smoke20

iTrader: (2)

wow this thread returns from the dead, great to see so many people with good info on this subject. as far as the tune goes, i didnt retune after wrapping exhaust but i did have an AF guage to monitor , it did change to low rpm AF but not tremendously, i think i went from 11.6 to 12.1 then it dropped back down still within the safety margin for my tune. each tune could be different so if you dont have an AF guage get one it could save you thousands of $$$. my car is down for the next 6 weeks stock motor and trans went so im reloading with a forged motor, stage 2 trans and im gonna pour the boost to it.

JD_Z28

iTrader: (19)

It would all depend on your A/F ratio within the rpms your now boosting in. Lets just say you're boosting three hundred rpm's quicker, this would be the area you would have to be worried about leaning out.

pdanrichey

iTrader: (4)

Got mine retuned...I did pick up at least a 1/2 pound of boost on the top end, not to mention that it spools up probably 7-800 rpms sooner !!

One thing I don't like about MAF tunes is how you can go into boost without going WOT and when you look down, your AFR is around 14.5.

It's still safe though I suppose b/c of not flooring it...less "compression" and all. Still, I don't like hearing the turbo spool up without seeing the AFRs in the 11s...

99Z28LS1

iTrader: (4)

****..... i noticed before i went wrapp, it took my turbo forever berfore it would spool. now just letting it warm up with the car until she gets to the mark will make turbo want to play without getting on it

Zombie

iTrader: (2)

That is very easy to fix, adjust the TPS vs PE enable (hot and cold) tables to a lower percentage. I believe I have mine around 33% TPS at 2800 rpms. That causes the ECU to go into open loop over 2800 rpms. No more lean AFR. I have my MAF setup dialed in really good and my a/f stays 12.5:1 until around 7psi, then it richens up to 11.0:1

Definately takes some time to get right though.

reocamaro

iTrader: (5)

I'm getting my engine rebuilt as I write this to you guys. Last night, I called the shop and told him I'd like to get the exhaust wrapped while the engine is out to make it easier to wrap some of the hard to reach areas. He seemed to get very precarious about wrapping it telling me that he wants to sign some papers wrote up by his lawyer incase the car catches on fire. Why hasn't anyone addressed this previously? Is it likely? Possible? What's going to catch on fire? :-\ Just askin' some questions.

Eatinstang4life

iTrader: (10)

He prob just taking all precaustions. I dont see why it would catch fire.

navymitch12

iTrader: (1)

if your car got a leak, oil or fuel it would soak into the wrap then could catch on fire. just dont let your car leak

ZL1Killa

iTrader: (17)

idk if it has been discussed earlier or not...but i have a buddy who does some racing and they wrap the exhaust all the way. after like 2 or so races the exhaust just falls apart from fatigue and stress... i have stainless steel headers (kooks 1 3/4), if i were to wrap the whole thing...would this eventually happen?? i mean obiously it would take longer...but just wondering.
cuz my buddy just said wrap up to the y and leave it alone, otherwise eventually your exhaust will fatigue

GH1086

Alright, so I just read the whole thread and I still have some questions. First of all, I already have Kooks LT's with high-flow cats that have been ceramic coated, those are not going anywhere right now. I've got a GT-67 turbo on a stock LS1 with an A4. The STS piping has been painted with some high-temp stuff but it didn't really affect it. It takes forever for the turbo to spool and I need to do something about that. My car is a daily driver through every type of weather including snow.

What affects the pipe's longevity more, climate or heat?

Should I spray some water resistant silicone/paint first then wrap the piping?

Any recommendation on what wrap is this best? Any real difference between brands? Or is it basically all the same?

How much sooner can I expect the turbo to spool? 500RPM's?

Now how about a turbo blanket, would putting one on affect the longevity of the turbo itself?

How much could that potential affect spool time?

Right now, the turbo doesn't spool until around 4000RPM's and that just sucks. I'm thinking wrapping the exhaust, a turbo blanket, some more boost (about 2 pounds more, total of 9 pounds), and a smaller (I believe) exhaust side turbine will hopefully get the turbo to spool at around 2500RPM's in 1st gear.

enginjoe

iTrader: (11)

2500 rpms is really soon for us rear mount guys. What is your set up? What trans, gears, stall, A/R? You might be in the same or similar boat I was in. I had a T67 with a .81 A/R with long tubes and off road y with 4.10 rear gears. I wrapped the y and it helped a little. I also raised the boost up to 8psi with meth injection. I am going back to stock manifolds and I'm going to wrap it all the way back. I am also going with a lower gear ratio (probably 3.42, but maybe 3.23). I don't know if you can get a smaller exhaust side than what you have. Besides you will lose some top end power. Maybe if you got a little more displacement you could do it. I think some of the guys have gotten low 3000s from what I can remember. You can use a small shot of nitrous if everything else doesn't work. Just some ideas here in a stream of consciousness...

JAvenger007

iTrader: (9)

stick with the T67. There was a member on here that made 500+/600+rwtq with one and just a cam. They spool slightly slower than T60 but you get more top end and mid. Lose the kooks and cats. You dont want a cat to go bad and start blowing into the turbine, especially if its an all weather vehicle, a lot of that stuff gets more wear and tear.

Zombie

iTrader: (2)

GH1086, go back to stock manifolds, wrap the entire exhaust system. This is the solution to your spool issues. It's a night and day difference.

Your headers are causing the majority of your issues. You can search for threads that I've started. I've tried many many different combinations, turbos, housings, exhaust setups, headers vs manifolds, different gears, 6spd vs auto, different stalls.

engineermike

Makes me wonder how MajorSpray gets his headers and 106 mm rear mount to spool up. . .

00WHITETA

iTrader: (1)

My turbo was spooling at about 3700-3800 and had full spool by 4500. Now that I have put a new filter on and wrapped the exhaust it is starting to spool at 3300-3400 and full spool by 4000-4100. It helped alot just haven't been to the track because it is in speed density mode with temp's in the 30's when tuned, so right now she isn't running to her potential. I need to get acouple bugs worked out than I can put it back into mass air mode. Than we will see if it really help any.

Jimmy