someone please answer quick !!!! yz400/426 head question

is there any difference between 2002 426 head

and yz 400 head ?

can i use my 426 cams in a yz 400 head?

I think i know one difference, the valves on the 400 are steel and not titanium is that all??

is there any difference between 2002 426 head and yz 400 head ?

can i use my 426 cams in a yz 400 head?

I don't know about the differences in the heads, but the 450 cam mod (auto decompression) was for the 2000 - 2002 YZ/WR 400F/426F.

PM me your e-mail address and I can send you the pdf.

The only difference is that the 400 head has a vacuuum port on the intake side that is not necessary on the 426. You can either cap it with a vacuum cap or drill the brass nipple out, tap the hole, and screw a bolt into it.

I have a 400 head on my 426 cuz I found a reconditioned, ported one cheaper than getting my valve seats cut...works bitchin'

funny thing is i found a cheaper ported 400 head too.........thank god..... or birdy426

funny thing is i found a cheaper ported 400 head too.........thank god..... or birdy426

awe shucks...twernt nuthin...

Who did the porting and valve work? Just curious.

Are you going with Ti or SS valves?

I would have to ask the guy i bought it from who did the work because i am not sure.

birdy, are you using 426 cams? is there any difference ?

I'm using Hot Cams for both the intake and exhaust, but the 426 cams will work, too. I don't think there's any difference in the grind between 400 and 426...the part numbers are different, though, maybe a different heat treat or surface finish for the SS vs Ti valves?

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