Hi,

In the off season over here in OZ I am doing some maint on my Gen 1 racecar (13B BP). It is a pretty quick front running car and it has been suggested I try a coating process on the exhaust (headers) etc, has anyone tried this and has any feedback?

Thanks...

http://www.performancecoatings.com/

http://www.amr-coatings.com/

 

it does work but maybe not as dramaticly as advertised. best result come from the coating on the inside and outside. it will reduce underhood temps. it is widely used in pro race shops.

 

why not just wrap the exhaust??

 

coatings work pretty good at keeping corrosion and temps down. I have used jet hot on my motorcycle headers and recommend it to anybody who is serous into racing. check out
www.jet-hot.com

 

First off header wrap doesn't work as well. They also have a tendancy to trap moisture between it and the exhaust, which is very bad for corrosion. And I know of more than one motorcycle racer that had it come apart and get caught in the chain.

 

I had my 12A Street port header on my 84 road race RX-7 wrapped with standard 2" header wrap for about a year. The outside of the header probably lost a good 1/16" of thickness in rust and corrosion. In my opinion, rotary engines create too much heat and will destroy a wrapped header in a short time. Get a coating and stay away from the wrap.

-Trent

 

OK, so roughly what does it cost to have a header coated?

 

I have tried both versions on my 13B race car. Keep in mind that this car is never run on the street so my issues may be different to yours. Also, when running it is at at full throttle for 75% of the time.

Header wrap was a no go for me. I wrapped my header all the way to the collector, for heat control in the engine compartment and to keep the speed of the exhaust gases hot and fast. After 11 races I had burnt 2 holes the size of a quarter at the outside of the bend just outside of the exhaust port. The metal had turned to a sandstone consistency and could be flaked apart with a fingernail. After consulting with a friend of mine who is a metalurgist, he told me that trapping exhaust heat in low carbon steel at this point of the pipe, caused repeated overheating/ rapid tempering of the metal and destroyed its cohesion and had it trying to revert to base composition.

Next header I tried a home applied ceramic pipe coating. After trying to follow the instructions to the letter, the pipes looked great but the smell while curing was something else. The coating lasted 3 races before it started to flake off like normal header paint. I then reade that the coating is only good to approx 1500 degrees and that a rotary under high load/ full throttle exceeds that and if at all lean cna exceed 1800 degrees.

Now running a Racing Beat Road Race header with their factory applied ceramic coating. Lasted for 3 years and close to 30 races. Just saw my first flake end of last year. It is in the space where the 2 pipes cross and more than likely the factory application of ceramic was not perfect. I highly recommend that the ceramic coating be applied to new pipes by professionals who have the equipment and cleaning solutions to do the job right. In Canada I can have a header coated for under $80 bucks. I am not saying that you can't do it at home, but you will have a better chance of success with the right product applied correctly.

 

Wow, great to hear your experince.
I think it will save me some time and money.

 

That's weird, what kind of header wrap did you use? I used the stuff from Jeg's on my RB headers. They've been on there for 3+ years, which has included some street/wet driving, and the headers are still intact. They've got a little spot rust on them, which I cleaned while I had the wrap off.

To tell you the truth, I was kind of surprised to take the wrap off and not see massive holes in the header.

 

I can't remember the exact brand, but it was 2". I think the problem was more along the lines that I was using cheap headers. The first one was a Pacesetter and I just believe not up to sustained heat from a rotary, with the header wrap retaining the heat. The second version was a Racing Beat clone made locally. Warped header flanges as well as flaked and rusted. Finally broke down and bought the RAcing Beat one. Cost me over $500 Cdn by the time it was landed but has been a very worthwhile expenditure. Durable as well as quieter. Got rid of some of the tinny note of the other 2 headers.