Are the patterens of all the F22/F23 ab 12 head to manifold bolts the same, will the same header work for all af them?

 

Good question. I would venture to guess the F22 headers are the same but different from F23 headers. Try getting the part #'s for the header gaskets and see if they match. That wont mean they are the same but at least the size, shape, and pattern of the header primaries is the same.

 

The F22b1 and the F22b2 share identical header bolt patterns. Not sure on the f23. But the o2 sensor on the EX is longer then the o2 sensor on the LX/DX/SE models (94-97). If you have a LX/DX/SE and wanted, for instance, a Greddy header, you would need to buy a stock EX O2 sensor. Hope that helps.

 

yeah the bolts are the same, but for the 5th gens the f22b1(vtec) motor had a 4-2-1 header from the factory while the LX has a more restricted header config.

 

Same with the 4th gen obviously.

 

f22a and f22b are different, bolt pattern and design, 4-2-1 on b (EX) models with o2 next to cat, whereas f22a much farther up... plus the f22b1 sensor is short as hell. less than 6 inches, they mount in different locations on each... pain in the *** really

 

I think you are refering to the downpipe while smokin rubber is asking about the header design itself, and whether the top of the header will bolt up to the 4 exhaust outlets on the engine block. I know it sounds complicated, but its late. Sorry.

 

f22 and f23 are completely different...

on my swap I used the upper exhaust manifold from the F23 and the lower one from the F22...which is a major restriction...but now I got mah header

but no, the upper exhaust manifold from the F22 won't come close to fitting on a F23 head

 

yes, that and the 02 sensor housing, yu0 have no idea the difference the 2.5" made when i had that stock portion deleted

 

ok since we're on the subject, will my 91 lx o2 sensor fit an EX downpipe??? cause i just bought a ex header with downpipe and i haven't tried yet. i know i have to extend the o2 sensor. well anyways the downpipe already has an O2 sensor on it but i don't know if it will work. thanks!!!

 

yes, it will fit

 

thanks, thats exactly what I needed to know,