JD_Z28

iTrader: (19)

If you're spooling the turbo faster then you're going to in boost in lower rpms. I pretty sure you would need to re-tune?

engineermike

Right, but increasing the efficiency of the turbo means that it'll take less exhaust pressure go create a given amount of boost. Less exhaust pressure means less residual exhaust in the cylinder, meaning more air in the cylinder, meaning more air flow per psi boost, etc. . .

koolaid_kid

iTrader: (21)

Not trying to disagree, but I am afraid I don't quite follow your logic. I have a fairly good understanding of turbines, and what it should mean is that you are utilizing more of the power potential available. As far as requiring a new tune, I would have to see proof before accepting this point. It may provide more power with a tweak or two, I would tend to agree. However, I would have to see empirical data on this as well.
Those who have done this mod have reported faster spool up times as the most noticeable change.

JAvenger007

iTrader: (9)

Has a verdict been reached as far as what setup is seeing the best results?

bbq paint or high temp silicone (which seems to last longer?)
then HVAC (does homedepot sell this stuff?)
then header wrap? (autozone sells this?)

seems that some are saying HVAC stuff doesnt help and others disagree.
Still interested in the tune issue also. Even if a tune is not "needed" it could still benefit from utilizing the changes in spool and exhaust efficiency IMO

pdanrichey

iTrader: (4)

TRT just did mine...I'm picking it up this afternoon. Billy (who is awesome btw) emailed me and said that Dustin was tuning it and driving it around...said it was pulling incredibly hard...like a totally new car. I'm looking forward to confirming his statements tonight

About the tune, yes, you need a few tweaks. Timing tables in particular will need to be changed to compensate for boost kicking in. PE Tables will need to be adjust slightly as well to add more fuel at lower rpms. Not to mention...doing this has a tendency to make you run more boooossstttt. I have a 7.4psi spring the wastegate and only hit 6.5psi after running the crap out of it...I should pick up that extra pound now.

koolaid_kid

iTrader: (21)

Excellent. We would be most interested to see the increase in horepower and torque. A comparison in curves would also be nice to see, since it should be coming into boost at lower rpms than unwrapped.
Good info on the tweaks as well, since someone with programming software should be able to figure it out, although on a dyno would obviously be easier and quicker.
Score another one for TRT. Sure wish they would have been around when I bought mine. I would have made the trip to Texas just to have them do the work.

pdanrichey

iTrader: (4)

Actually, I'm not getting it redyno'd... Maybe I'll will though now. I was looking for more efficiency for the most part. I'm not really into drag racing at the track, I just wanted to spool quicker on the street and maybe better gas mileage.

miamifan3413

iTrader: (1)

Hotter air flows quicker than cold air

koolaid_kid

iTrader: (21)

Sigh.
Please read the entire thread to understand the magic that is at work here.

koolaid_kid

iTrader: (21)

Sounds like you don't have the software. If not, the person who dynoed it the first time should just charge a smaller fee, since it is tweaking only and not a full tune. Just an FYI.
Not racing, eh? Just trying to get to the grocery store a little quicker?

pdanrichey

iTrader: (4)

No, I own HP Tuners and TRT is re-tuning it for a small(er) fee. It's just the Dyno Time that cost another $50. I'm trying not to **** off the wife anymore than I already have .

All it will cost me would be another $50 to get it dyno'd on the same dyno I got the original runs done on.

CantKeepemhooked

my question is....... if the exhaust gases are hotter which touches the turbo, wont the heat just transfer over to the air impeller side and increase IAT? i read this entire thread and havent seen this question

koolaid_kid

iTrader: (21)

Yes, some of the heat will transfer over to the intake side through conduction and increase IAT. Yet another argument for an intercooler.
However, heat is a form of energy. The turbo uses this heat to provide more power. The entire theory is a bit beyond this thread, but you can read more here which may help to explain why. (My apologies for having used a ricer site, but it is fairly well written and they tend to avoid engineering-eze).
http://www.dsm.org/menu.epl?item=246

JD_Z28

iTrader: (19)

Have you guys re-tuned your car after heat wrapping the exhaust?

navymitch12

iTrader: (1)

yes....you should

more boost at any given time should have the car tuned to add fuel for that

pdanrichey

iTrader: (4)

They re-tuned mine but I didn't get it re-dyno'd. I am pushing 7psi now vs 6.5 psi before. The boost also kicks in a lot quicker and the lag is mostly gone.

I'm guessing I picked up about 12 - 15HP on the top and probably 20ish under the curve. It definitely pulls harder down low. In 5th gear at 70ish mph, if I push the pedal down half way, it goes into boost, which is kind of bad b/c it a MAF tune, not SD...

99Z28LS1

iTrader: (4)

they retuned mine not too long afterwards...... i got cam not too long after the wrapp

JD_Z28

iTrader: (19)

I was just making sure guys. Thanks for the feedback

99Z28LS1

iTrader: (4)

i normally dont dyno tune, i usually have Dustin street tune it because that where i will be racing my car 99% of the time. but after cam, i had to see what she made

pdanrichey

iTrader: (4)

My exhaust housing fell apart this afternoon

Not exactly sure what happened other than the lip came undone from the housing...so my exhaust tip, "down-pipe" if you will, is no more

It's wickedly homo if you ask me...I didn't even know this could happen???!!!

So, back to TRT I go to have them pull the housing off, clean er up and weld the pipe and lip back on. This really is becoming a money pit!!

I guess it's alright to drive for now except I want to keep it out of the rain, so that limits me for the next few days .