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Discussion Starter #1
I’m looking for someone selling an aftermarket header that doesn’t need modification for my 89, any help would be much appreciated. I just finished building the motor and the header is one of the last pieces of that puzzle - would be cool to get that sorted.
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That is a beautiful engine.

There are a lot of bogus headers out there that may not properly clear starter, pan, and other. I don't know of any that are a direct bolt on to the downstream exhaust. Stan's has a good reputation and I have one on my supercharged car, with a custom pipe downstream to the cat.

Really a 4AGE header in most cases gets two things, neither of them performance: It looks neat. It replaces the crack that always occurs on the original cast manifold.

Whenever anyone starts talking headers I like to refer to my favorite 4AGE tuning authority, Billzilla, (Bill Sherwood's Stock 4AGE Info) who says this:

EXHAUST
The factory exhaust manifold is very good with all types, both FWD & RWD, and up to about 200hp they are better than just about every aftermarket exhaust manifold available. They are a 4-2-1 design, and all types fit all the engines, with the exception of the 20v manifold, which has the two bolt holes on the extreme ends in a slightly different place to the 16v ones. But - by slotting the holes on the 16v manifolds, they can be made to fit quite easily on a 20v; usually this is done to convert a 20v to a RWD car. You'd be far better off getting things such as lightweight flywheels, etc, to improve performance, as the engine will definitely benefit from these, rather than one of dubious increase at best ...

(Bill Sherwood's Modified 4AGE Page) And this if your build is in excess of 200hp:

The factory exhaust manifold, which was good up to about 200hp, now must be replaced with a good set of aftermarket extractors. By good, I mean that they must fulfill a few criteria to make them good rather than merely average -
  • The four pipes MUST be equal length, to within less than 1/4" or 6mm.
  • The four pipes must NOT have any crushed bends in them anywhere at all.
  • The four pipes must go into the collector in the same sequence as the firing order of the engine, ie, 1-3-4-2. Many of them simple put the pipes into the collector in any order that's convenient, but these sort make less power than a good set.
  • The collector must be around the 60mm dia mark. Many aftermarket extractors have 50mm collectors, and this is not large enough to make big HP.
I don't think my Stan's fulfills these specs and my build is stock anyway, so I might just revert to the cast original.
 

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Discussion Starter #3
Thank you, it’s been a fun motor to build lots of goodies in there. I’ve thought of welding up the crack on my oem header and running it just so I can be closer to getting the motor in - maybe that is the route I will go. Im familiar with Bills page but I have not heard of Stans exhaust , I’ll have to look into that further.
Now that the engine is nearly complete I’ve moved on to the transmission, I can’t believe how well it’s held up I don’t see any signs of anyone ever being into it prior. Good ol’ Toyota ! I appreciate your response
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