Header

[Socalman]

I need to order a header for this engine to go into my 521. Anyone know the difference between the 2wd and 4wd D21 header? Which would best suit the 521?

Edited April 15 by Socalman

[Stoffregen Motorsports]

I have no idea...

[datzenmike]

4x4s have different torsion bars. I would guess that 2wd will be the closest but the D21 is three generations away from the 521. The KA engines uses an almost identical transmission so it will clear that, just has to clear the torsion bars. 

[Socalman]

Ok. I have no torsion bars, I’m running coilovers on the 521. 

[datzenmike]

Then either may work. Like I said the header is for a totally different engine that is three generations after the 521.

[Socalman]

Thanks. 

[yenpit]

Your best bet is to look for a "shorty" header, as those tend to fit most chassis.  Headers fit the engine that came in any given chassis.  I am not familiar enough with these later engines.  I assume your exhaust port configuration is O O O O, not like the earlier NAPZ OO  OO (similar to a Buick Nailhead)?  That said, look for a "shorty" header for your engine & hope it clears whatever configuration you have, then hopefully the exhaust outlet/collector is easily accessible, in your chassis. 

[datzenmike]

NAPS and KA24E are similar OO  OO. So similar that with a slight porting a KA manifold will fit the Z series heads.

[Socalman]

I’ve got a D21 header coming, will update once I get motor in sometime in June. 

[mrbigtanker]

Torsion bars is not your problem its the swing out of the headers to steering column that's the problem. Hope they fit. post pics