Side Mount Exhaust
 

Our flat floor debuted at Road Atlanta and it was a success (1st overall out of 84) however, long term we are going to eat transmissions and differentials due to the heat. This is for an endurance racing application and we got lucky with really cold temps at RA. I've gotten tech approval for a side mounted exhaust and plan to route it around the steering column, and out the driver side fender along the side of the car. I found a thread that mentions another thread about this topic, but I can not find it.

Has anyone done this? We have a JDM 4-2-1 that we could modify for this routing or we could make a custom header. Currently we run a RB4-1 Header, however if we move to the JDM header, we get our points back and can use it for a SKUNK2. We believe this will off-set any power losses.


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I know Ryan has a side exit exhaust. However, Im not sure how applicable his info will be given its lack of stock-ness.

Different engine, but similar idea: Hypermiata

Thanks for the link. This is very helpful. That is ALOT of cutting and welding, lol.

Seriously doubt that you’ll get an exhaust and a front wheel in the driver fender at the same time functionally. I think you’ll have to run under the car

Everyone keeps posting links to this pic/thread while ignoring the like 50+hrs of fab Ryan put into completely rebuilding the rockers from scratch lol

But the OP wants to know if it is possible. Not how hard it would be. Its possible and probably a PITA to get done.

I am aware of that there will be a decent amount of work. I already have about 40 hours into the flat floor. I am interested in seeing more about HOW people have done it and what were the challenges. Ryan's write-up is a big help. Is he the only one who has done this?


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Something to realize about Ryan's is that he also only has one tube coming off the head vs a header/manifold coming off of the miata head. That makes it a bit "easier"

So the OP needs to swap LFX or LSX to be a cool kid. Seems easy enough.

I may eventually go ecotec or k24 swap(rules don't allow big hp swaps).

Going to start cutting tomorrow. If I ever do the swap, I'll have practice so I can cut the other side as well.

I'll post pics for those interested.

Why not flip the exhaust upside down and run it forward and exit it in front of the tire or up through the hood?

has to exit behind the driver

cabin exit right behind the driver. Its short, light and you get a free heater

When we did the flat bottom on Vegas, we had the entire exhaust ceramic coated and ran coolers on the differential and transmission.

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Most of the cutting is completed, using Ryans as inspiration. I appreciate the help!

the toe box will certainly be warm

but it will make trans changes a lot quicker!

Some of the welding completed. About 25 days till the race.
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