Is it OK to use exhaust wrap?

[GTP Version 2.0]

I have a ceramic coated crossover from ZZP and I was wondering if the crossover can be wrapped. I know that the exhaust manifolds can't be due to the risks in cracking, but is the crossover pipe the same type of metal?

[BNaylor]

Why use exhaust wrap?

The purpose of the ceramic coating is heat control or acting as a thermal barrier. Reduces engine compartment temps.

[GTP Version 2.0]

Well like I said..ZZP. The coating is great over the stock application, but it doesn't do that much for underhood temps. I was using a 12"x6" fiberglass thermal reflective blanket from heat shield products in addition to the ceramic coated crossover to protect the TB, but I still noticed that there was a considerable amount of heat coming from the area (I have a TB spacer and my custom CAI tube was still burning hot). I wrapped it with exhaust wrap and moved the 12"x6" blanket to cover the rear flange and EGR tube. The underhood temps are considerably lower but I wanted to know if I am risking cracking my crossover.

[BNaylor]

Personally I think you are defeating the purpose of the ZZP ceramic coated crossover pipe. (Note: Coated inside and out). Really no need to use exhaust wrap. Using the wrap will probably cause more heat retention instead of dissipation. Will it cause cracking probably not but you never know for sure. I have ceramic coated SLP brand headers (real) on my GTP and do not any exhaust wrap.

What other mods do you have? Reprogrammed PCM? Fan turn on points?

Also, have you run a test of knock retard (KR) to see if any real or perceived heat is causing an intake charge issue? Last time I checked the underhood temps will be higher on L67 engines whether modded or stock regardless.

[GTP Version 2.0]

I have seen the other exhaust coatings on other exhaust parts and ZZPs is junk compared to them. Honestly the ceramic coating on the ZZP crossover (at least on my unit) looks like two coats of gray paint. My under hood temps are considerably lower with the exhaust wrap on. I can drive around for an hour and still grab the exhaust crossover barehanded, but I sure as heck won't touch the supercharger.

My mods are the following:

ZZP 1.9 High Ratio Rockers
ZZP PLOG (Front ceramic)
ZZP ceramic crossover
ZZP 3in to 2.5in DP with High flow Magnaflow Cat
CAI
TB Spacer
Thrasher Modular Pulley System with 3.4 pulley
Ported SC (inlet 70mm and outlet porting)
ZZP ported LIM
ZZP PCM
ZZP Fuel Pump Rewire
ZZP Alternator Booster Kit
Thrasher Shift Kit
NGK Iridium 6's
PRJ 10.4mm wires
180 thermostat

F-Body Brakes with 12in slotted/drilled rotors
GMPP full suspension package (front/rear sway bar, strut tower bar, trailing)
18in 2007 Pontiac G6 GTP rims
8000k HIDs
blah, blah, blah

I live in Az and summer is coming. With el nino its going to be another hot one. Anything I can do to lower under hood temps will be my first priority.

[BNaylor]

I live in El Paso about 300 miles from you and it gets hot during the summer here too. I really don't see whether you have any issues with excess engine heat. If you can touch the crossover pipe after one hour of engine operation then it appears to be working no matter how poor ZZP's product may appear to you. Regardless your method of testing is not too scientific. Have you run a thermocouple test? With simple digital volt meters with temp capability you can measure engine compartment heat.

On the ZZP PCM what is your fan turn on point? 180 degrees? I only have experience with DHP or Intense PCMs. Also, do both your cooling fans turn on after you turn the engine off? Called rundown protection where they are programmed to run for 1-2 minutes.

Again have you checked for any knock retard (KR) or do you have any noticeable signs like driveability issues that you are being affected?

The bottom line is it is your decision to run the exhaust wrap whether there is any real benefit or not.

[GTP Version 2.0]

By "it" are you referring to the ceramic coating or the exhaust wrap? For the sake of argument let me clarify. I can only touch the exhaust crossover with the exhaust wrap on. So ZZP coating could be crap and its merely the application of my exhaust wrap thats keeping the ambient and surface temps down.

To answer your question the ZZP PCM turn on is at 180 with a two minute cool down after you turn off the engine and both fans do come on. I haven't scanned for KR yet as I am still researching what scanner is the best bang for the buck (any suggestions please let me know). I will run a thermocouple test this weekend as a last resort if I can't borrow my friends IR gun (better accuracy and better purpose for this test). Furthermore, I do not have the stock applications (control) for comparison so I don't really understand the point of measuring the temperature.

Besides even if ZZPs ceramic coating was the best on the market, the addition of exhaust should only help the application better insulate the exhaust gases to maintain a higher velocity. In exhaust applications you don't want heat dissipation, you want heat retention, thus the use of ceramic coatings to further insulate the gases. Hotter gases travel faster. You merely want the heat to stay in the exhaust line and not transfer across a barrier. A proper ceramic coating shouldn't allow that much heat to escape. The whole point of using ceramic is that its a non-metallic coating and not a metallic coating that has defining properties of heat and electron transfer. FRP or GRP commonly known as fiberglass is silicon based fibers that work as great insulators. The only thing better than that are chemical compositions of ionic bonds, but unfortunately are extremely brittle, thus the reason you don't see ceramic exhaust wrap, but rather ceramic coatings or spray applications.

I merely wanted to know if the crossover could be wrapped without cracking. Also don't think of it as that I am trying to get the exhaust gases hotter, but that I am trying to keep the engine compartment cooler.

(good reference link) http://www.torquecars.com/tuning/exhaust-wraps.php

[BNaylor]

Originally Posted by GTP Version 2.0

(good reference link) http://www.torquecars.com/tuning/exhaust-wraps.php

Did you carefully read the article?

The biggest factor in exhaust failure is rust caused by moisture and not heat. In fact keeping the heat in the exhaust will help to reduce the moisture content.

Adding a wrap will protect the outer surface of the exhaust from water so there is actually more to be gained from adding an exhaust wrap than not having one.

The main reason to use exhaust wrap is because of moisture/water? Thats a good one. Are you drawing in air to the intake system from the engine compartment? What type CAI do you have? The object is to keep the intake charge as cool as possible to help overall performance and keep KR in check. The exhaust wrap will not keep the supercharger any cooler or reduce the temperature of the intake system. Thats what an intercooler is for on modded supercharged engines.

IMO simply ceramic coating an exhaust component like a crossover pipe is ineffective so most likely a waste of money. Another ZZP gimmick. The principle works on ceramic headers due to the tuned design and exhaust scavenging effect. It accelerates the pulsed-vacuum effect on tuned headers, resulting in more effective scavenging of cylinders. The increased velocity of exhaust gases produced by higher exit inertia not only clears each cylinder more quickly but it draws in the next fuel/air charge more efficiently. I've tuned and built HP engines over the past 35 years from Chevy small blocks to Mopar big blocks and the L67 Series II 3800 engine and never used or needed exhaust wrap. The worst thing to do was use outer exhaust wrap which caused documented cases of mummified headers. Meaning literal disintegration of the header's steel tubing. Exhaust wrap which is an outer-only thermal barrier would block the heat from radiating through the exterior metal surface. Heat retention is one thing but heat coming off the exhaust system needs to be dissipated regardless.

Not only did you inquire about cracking but you asked "Is it OK to use exhaust wrap"? so that sets up a general discussion of the pros and cons on an automotive based forum where all with different or similar views are welcome to weigh-in.

Another option is to run a poll.

[GTP Version 2.0]

I would say that we should agree to disagree, but you're not staying on one subject long enough to do so. I merely wanted to know:

"I have a ceramic coated crossover from ZZP and I was wondering if the crossover can be wrapped. I know that the exhaust manifolds can't be due to the risks in cracking, but is the crossover pipe the same type of metal?"

Then you asked"

"Why use exhaust wrap?
The purpose of the ceramic coating is heat control or acting as a thermal barrier. Reduces engine compartment temps. "

That was agreed and understood. But doesn't address the initial question. If it was a qualifying question to better ascertain the primary then ok, but then you said:
"Personally I think you are defeating the purpose of the ZZP ceramic coated crossover pipe"


But if the ceramic coating from ZZP is not holding up to its purpose, then I am going to try exhaust wrap on the crossover which brings me back to the initial question"

"I have a ceramic coated crossover from ZZP and I was wondering if the crossover can be wrapped."

Furthermore, why question my primary question if you yourself believe:

"IMO simply ceramic coating an exhaust component like a crossover pipe is ineffective so most likely a waste of money. Another ZZP gimmick."

By you stating this you acknowledge that ZZPs coating is probably crap, thus through your own reasoning in retrospective view you come upon my primary question:

"I have a ceramic coated crossover from ZZP and I was wondering if the crossover can be wrapped."

Also I am barely in the neighborhood of 300hp so I do not have some HP monster. I merely want to know if I can wrap them safely for my application. I have already done so, but if the risk is too great then I will take it off, but so far I am very happy with the results.

[BNaylor]

To put it bluntly I think you are beating a dead horse. If you carefully read posts my opinion(s) is clear. No benefit to using exhaust wrap so my reply is no need to use it. Could it cause any damage possibly but we would be speculating. If there is a real benefit or proven advantage then show me.

Also, if you are already using the exhaust wrap on your ZZP crossover pipe then why pose the question(s) or issue after the fact? As I stated earlier the choice is yours no matter what others say whether for or against so you be the judge or decision maker.

[richtazz]

Exhaust wrap, if not applied 100% correctly, can be dangerous. If moisture can get inside, it can actually grenade due to the rapid vaporization of the trapped moisture.

That being said, you CAN apply it to any surface you want, but it may or may not cause unwanted side effects. It most likely will reduce underhood temps, but at the expense of longevity of not only the crossover pipe itself but any downstream exhaust components due to the exhaust heat being retained in the pipe beyond what it is designed for.

With your mods, have you looked at A/F ratios to see if you're running way too lean? It seems you wouldn't have overlooked something so simple, but sometimes we do when working on our own stuff.