Competition headers - carbs too hot

[moyest]

Latest problem is that my headers sit too close to the underneath of my carbs & manifold - so the fuel tends to "boil" a bit and performance drops off.

Anyone know where I can get my hands on some competition headers for a Z? The ones that drop straight down off the side of the engine, rather than extending out under the carbs?

The more clearance I can get between my exhaust and the carbs/manifold, the better!

Thanks!

[240Zdragon72]

try zcarparts.com (MSA) look in the links under M

They have a 3 to 2 performance header for a good price.

[kyteler]

For the price of new headers wouldn't some form of heat coating and a heat shield be a more viable option?

I have no idea, I'm wondering myself.

[240Zdragon72]

it would. I did not think of that one. I was in the process of buying a new one for the Lady, and that was on my mind. You could get some heatwrap or if the headers are in good shape, get ahold of Jet-Hot (the link is also on this website under links:stupid: ) maybe that might be a better option. Good lookin out.

[moyest]

Yup, I thought about coatings for the headers, but they are SO close to the manifold (touching at the front!) that I don't think a coating would do it!?

I also wondered about fabricating the headers from scratch, but cost would be around AUS$600 (approx. US$490).

I'll check out the MSA site - thanks for the advice guys!

[kyteler]

Well, should you get new headers and want to fob off your old manifold touching ones, I may be the kind of fool :stupid: that would buy them, only problem would be freight coupled with how much you'd want for them, judging by your previous response you're in Aus, but at least it wouldn't be as bad a freight price as if they were to come from Japan or Yankeeland.

I'm in NZ btw.

[seerex]

I looked into the jet hot coating , according to their stats it reduces the heat quite a bit , I don't have a heat issue with the carbs but I wish I had sent it to them before i put it on the car also if you look up chinoz he has a custom heat shield he did that helped alot

[trs]

try stewart wilkins motorsport in Sydney. He has a website somewhere but I can't remember the damn link.

He sells headers for around $495.

[symon]

You could also try ducting cold air onto the exhaust manifold to help keep it cool. I think it is better than wrapping the manifold as if there is excess heat it can warp them. Hope this helps

[Chino 240Z]

Heat is a big problem and a bigger problem on a hot summer day! After loosing time and money sitting at the track last summer, I was determined to minimize the heat / carb problem ya know. Here is a pic of the heat sheild I cut from scrap stainless steel and bent it fit under the carbs. I have also installed a piece of duct from the open hole next to radiator support to flow air under the shield too. Now the carbs don't even get warm! I check them after coming in from a 1/2 hour of full throttle, not only is it not hot but makes working & tuning easy- not hot. It may not look original but it works.

I have the jet hot on my Formula Firebird car headers and it works too. I will some day get the headers on the Z done too. But heat is not a problem any more. It would be to get rid of the wrapping, and make them last. If you coat something, besure you demand inside besides outside.

heat shield.bmp

[moyest]

Chino, that's one serious heat shield!

Regarding the cold air ducting, I was told to simply remove the passenger side floor vent pipe which sits in the corner next to the radiator. It disables the passenger-side floor vent (or if you open it, it poors in HOT air), but the extra air flow helps to keep the engine bay cooler.

However, the "cold air" options only help when the car is moving. I think the coating and/or heat shield options are a better solution.

I might try coating the headers first, but can you coat slightly rusty headers or do I have to start fresh with nice condition ones?

I'll also check out Stewart Wilkins Motorsport - thanks TRS!

Cheers

[Chino 240Z]

When everything is back in place it's not that serious looking, and you can also now see the duct at the bottom. Yes the car needs to be moving for the duct to help, but then again this car isn't really doing anything else but moving!

I don't know about letting in engine compartment air since you get enough exhaust fumes from any car infront and not to mention your own. I know after a long run there is a build up inside and with a helmet on it can be :sick:

I was trying several options to cut the heat and it did.

Oh and yes you can coat rusty surfaces. That is one of their sales pitches. The jet hot coating makes them look fresh and new besides keeping the heat in the pipe for the heat scavagening benifits. They sent me a demo video before I had it done. I would especially do new ones. Good luck.