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-   -   FB Heat Issues w/ Header and Steering (https://www.rx7club.com/race-car-tech-103/fb-heat-issues-w-header-steering-567370/)

Kouryou 08-10-06 01:13 PM

FB Heat Issues w/ Header and Steering
 
I was talking with a former Spec7 racer who told me of issues he had with the header "eating up" either his pitman arm or idler arm (can't recall right now which one) - the heat from the header would cause the steering to really deteriorate.

Is this an issue that I am going to encounter with either my 80 or 84 FB, and if so, is there anything that I can do to prevent it? I have an RB header / exhaust for both of the cars.

Thanks!

Kentetsu 08-11-06 12:33 AM

I've got the RB header too, and haven't had any issues of that sort. I think that if the header is getting that hot, you're ignition must be retarded...

Kouryou 08-11-06 01:06 PM


Originally Posted by Kentetsu
I've got the RB header too, and haven't had any issues of that sort. I think that if the header is getting that hot, you're ignition must be retarded...

I don't care who you are, that's funny...git r' done!

Me - "Ignition, are you retarded?"

Ignition (doing its best Carlos Mencia) - "Dee-dee-dee"

Thanks for the feedback Kentetsu!

speedturn 08-14-06 08:08 AM

The pitman arm is on the driver's side, and the idler arm is on the header side.

There is serious heat radiating from 45 minute races on my PP road racer 1st gen exhaust header, and I used to have problems with the idler arm bushings until I made a heat shield for the idler arm. I made the small heat shield out of a piece of aluminum, that leaves about an inch or two of airgap all the way around the idler arm. Mount the new shield using the idler arm mounting bolts. My idler arm bushings now last much longer.

My header runs so hot that one time when I was running a 20 minute session on a Clayton chassis dyno, that the radiant heat from the header caught the asphalt on fire in the dyno shop floor. I have heat shields between my exhaust and chassis most all the way from front to back.

I don't bother with the heat shield on my street port 1st gen daily driver. Street cars do not see the sutained high output heat problems that road racing generates.

KSTIIdude 08-14-06 08:19 AM

Mike VanSteenburg at ISC Racing sells brass bushings for FB idler arms that won't have that problem. I also haven't heard of anybody having bushing problems with the Moog idler arm that Mazdatrix sells.

I think the brass bushings are $20 and the Moog arm is like $70.

Kentetsu 08-14-06 08:45 AM

Get the Moog unit from www.rockauto.com Same one that Mazdatrix sells, but 20 bucks cheaper. Works great.

Kouryou 08-14-06 09:11 AM

Boootyful guys! Thanks for the advice - I'm thinking both heat shields and the Moog upgrade from Rock Auto (plus I have a discount certificate from them as a bonus).

Zyrano 09-04-06 11:48 AM

ok, followup question. This doesn't solve the heat soak issues, wouldn't a header wrap work better in terms of shielding everything? The other option I've been considering is ceremic coating the header.

Alvin

speedturn 09-05-06 04:29 PM

On my race car which operates at sustained hi power, I have ruined a set of headers by wrapping them. They over heated.

Re-Speed.com 09-05-06 05:34 PM


Originally Posted by speedturn
I have ruined a set of headers by wrapping them.

+1


Don't wrap it and expect the header to last.

-billy

spot_skater 09-05-06 05:45 PM

I've got a S4 NA, which I recently blew, and I have my RB header wrapped with some header wrap. Although I raced it occasionally, autocrossed it once, and drove it hard very often, I haven't seen a problem with it. When I've had to remove the exhaust, for whatever reason, the header was warm to the touch, while the rest of the RB exhaust was HOT. Just some info on wrapping.

If you plan on driving the car at sustained high RPM's, if it wound up destroying speedturn's header, I would stay away from it. Just throwing in some of my experiences with wrapping a header.

Zyrano 09-06-06 01:32 AM

ok, then what is the opinion on ceremic coating it? I'd like to reduce heat soak to the intake manifold. because between runs at autoxes, the manifold just soaks it all up...

speedturn 09-06-06 07:41 AM

Build a heat shield between the header and the intake.

wrankin 09-06-06 08:36 AM

True about the heat shield.

The ceramic coating should (in theory) reduce header temps since both the insides and the outsides of the headers are coated. However, you will also be putting more heat into the midpipe (it has to go somewhere). I'm not sure if this would pose a problem or not.

Anyone have experience with road race cars and coated headers?


-b


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