mgmike69 New Reader
12/11/09 4:57 p.m.

anyone had any experience with the bosal miata header good,bad or indifferent.what is the best recommendation

drmike New Reader
12/11/09 5:07 p.m.

My '94 came with a Bosal. It cracked open at the 4-1 pipe junction once, and I had to weld it back shut. I have no idea how old it is, but other than that there have been no problems. I have no idea if it functions as a power adder or not.

thatsnowinnebago Dork
12/11/09 5:31 p.m.

Racing Beat makes a really nice header for the miatas. Nice thick flanges and beautiful SS tubing

fastmiata Reader
12/11/09 8:12 p.m.

Having owned multiple miata, I have had several headers. I am aware of a moss header that I purchased and installed on one car that is still being used on another miata. It has needed some welding at a junction but is otherwise still working. My wife's '92 has a coated Jackson Racing header still functioning quite well and my personal '92 has an ebay stainless header.
You will get some benefit out of any header but I dont know that you benefit from purchasing the name brand. As I recall, the ebay header was less than $100 plus $15 shipping. You cannot beat that deal!

Keith SuperDork
12/12/09 11:18 a.m.

Every time I take a Jackson Racing header off a car, it's cracked. The RB units don't seem to have that problem. Never seen a Bosal in person or one of the eBay units, so I can't comment there.

If a $100 header doesn't actually provide any benefit, it's not a great deal. You won't necessarily gain anything from a header on a Miata.

Disclaimer - Flyin' Miata sells the Racing Beat header. I've owned JR and RB headers for my own cars.

BoxheadTim Reader
12/12/09 11:22 a.m.

I've seen some of the cheap ebay headers up close (at least the stuff you get over here in the UK) and I'd rather buy a used JDM header (easy to find over here) or something like an RB. I've had quite a lot of RB kit on my RX7s and it seems to be well made.

RandyS Reader
12/12/09 11:57 a.m.

I just picked up one of those NOPI 1.8 headers for $69. It is very thin but should last a couple of summers. It will eventually crack.

Rusnak_322 Reader
12/13/09 8:19 p.m.

I put a cheap steel eBay header on my 99 to get rid of the CA emissions. It needed a big hammer to not rub on the footwell. Is it the greatest thing ever? No, but it is a fairly decent looking part with thick flanges. I don't think that I paid more then $125 shipped.

Raze Dork
5/4/11 6:25 a.m.


RossD SuperDork
5/4/11 7:06 a.m.

Not to thread jack but I will anyways, does getting a ceramic coating on a stock miata exhaust manifold/header have any benifits? (A buddy can get it done for the cost of consumables...)

edit: I'm going to thread jack because this thread is OLD!

miatame Reader
5/4/11 8:43 a.m.

Up through '97 and after 2001 the Miata had a pretty good stock exhaust manifold (header). '99 and '00 got screwed with a log manifold and putting a header on those does show a boost in power. You can even use a manifold off a 2001+ Miata as I did on my '99.

Even a couple horse power can help a Miata but is that worth the cost? I went with a Racing Beat header on my '94 but only after I supercharged it and replaced all the other exhaust too. I wouldn't replace a header on a stock Miata (except for 99 and 00) unless I had money to burn.

The stock head shield does a good job of keeping heat out of the engine bay but it can never hurt to ceramic coat a header...but not sure it is worth the effort. If it is already off, sure, do it. You won't see any power though, just possibly slightly cooler under hood temps.