Headers: Wrap or not? Coat or not? - Page 2 - ZR-1 Net Registry Forums

WARP TEN · 03-19-2016

Agree with coating. When they are coated professionally I believe they are coated both inside and out. Reduces het for sure over uncoated. I don't know who Marc used here in the Chicago are but they were well done. Never discolored in the 10k miles I put on the car.--Bob

MuRCieLaGo · 03-19-2016

I paid US $500 shipped for the headers. I'm not sure I want to send them and pay 50% of the original price for a coating. What do you guys think? OBX are pretty cheap...

efnfast · 03-19-2016

I wasn't sure either, but I did.

ghlkal · 03-19-2016

My SW headers are coated. As others have said, it's for temperature control. I felt it was important after researching it and getting the opinion of several folks I trusted.

JFFerner · 03-20-2016

If the engine compartment is cooler with coated headers,where does the extra heat go? Jim

efnfast · 03-20-2016

Out the tail pipe.

RussMcB · 03-20-2016

Quote:

Originally Posted by MuRCieLaGo

I paid US $500 shipped for the headers. I'm not sure I want to send them and pay 50% of the original price for a coating. What do you guys think? OBX are pretty cheap...

IMO, don't bother with the extra hassle or cost. Use them as is for 5-10 years then if you think they should have been coated, coat your next set.

secondchance · 03-20-2016

Heat retention within the header is not only about keeping under hood temp cooler. When the exhaust cools rapidly after exiting the exhaust port resulting contraction of exhaust impedes exhaust scavenging.
Personally, I am not a fan of exhaust wrap because of fear of oil leak, soaked wrap resulting in possibility of fire. For this reason, I went with Jet-hot coating.

Paul Workman · 03-20-2016

Quote:

Originally Posted by RussMcB

IMO, don't bother with the extra hassle or cost. Use them as is for 5-10 years then if you think they should have been coated, coat your next set.

I agree, Russ. It is a decision that can wait; a delayed decision w/o consequences beyond convenience of disassembly/re-assembly and some gaskets: can be done at any time, really. And, I'm willing to bet coating will never be done later, if not before the headers are installed for the first time...UNLESS the owner is a WAXER!

AND, just because of my sometimes contrary nature, (and some knowledge of physics) I don't subscribe to the notion there is significant heat retention to have practical effect on the SW or OXB (knock-off) headers in ZR-1's due to several factors:

e.g. exhaust velocity vs. practical heat dissipation in the relatively short length of the primary or collector tube(s), i.e., the thousandths of a second it takes the gas to pass through the primary tubes...etc, etc.
or the fact the majority of the tubing is shrouded; not substantially exposed to enough outside air flow to practically 'sink' the temperature of the exhaust gas (when combined with #1)

But! To each his own. No harm done, either way, I recon!

secondchance · 03-20-2016

Quote:

Originally Posted by Paul Workman

I agree, Russ. It is a decision that can wait; a delayed decision w/o consequences beyond convenience of disassembly/re-assembly and some gaskets: can be done at any time,

Enough pain to do it once. I really didn't want to remove, coat and reinstall. But then again, I ended up pulling and reinstalling the motor twice in 16 months...

03-19-2016	#11
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,095	Re: Headers: Wrap or not? Coat or not? Agree with coating. When they are coated professionally I believe they are coated both inside and out. Reduces het for sure over uncoated. I don't know who Marc used here in the Chicago are but they were well done. Never discolored in the 10k miles I put on the car.--Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"

03-19-2016	#12
MuRCieLaGo Join Date: Aug 2014 Location: Trois-Rivieres (QC) Posts: 473	Re: Headers: Wrap or not? Coat or not? I paid US $500 shipped for the headers. I'm not sure I want to send them and pay 50% of the original price for a coating. What do you guys think? OBX are pretty cheap... Last edited by MuRCieLaGo; 03-19-2016 at 01:27 PM. Reason: English mistakes

03-19-2016	#13
efnfast Join Date: Nov 2011 Location: Dunbarton NH Posts: 7,486	Re: Headers: Wrap or not? Coat or not? I wasn't sure either, but I did.

03-19-2016	#14
ghlkal Join Date: Jan 2012 Location: Wisconsin Posts: 887	Re: Headers: Wrap or not? Coat or not? My SW headers are coated. As others have said, it's for temperature control. I felt it was important after researching it and getting the opinion of several folks I trusted. __________________ 1990 ZR-1 #2180 Red/Black Many of the usual mods for 460HP, tuned by Marc Haibeck ZR-1 Net Registry Member #1548

03-20-2016	#15
JFFerner Join Date: Jan 2012 Location: Dallastown, PA Posts: 189	Re: Headers: Wrap or not? Coat or not? If the engine compartment is cooler with coated headers,where does the extra heat go? Jim

03-20-2016	#18
secondchance Join Date: Aug 2006 Location: McLean, VA Posts: 3,723	Re: Headers: Wrap or not? Coat or not? Heat retention within the header is not only about keeping under hood temp cooler. When the exhaust cools rapidly after exiting the exhaust port resulting contraction of exhaust impedes exhaust scavenging. Personally, I am not a fan of exhaust wrap because of fear of oil leak, soaked wrap resulting in possibility of fire. For this reason, I went with Jet-hot coating.