Header bolt lenght for y-303's??

[fox racer]

ok, i just bought stage 8 header bolts, but i got the ones that are stock length, (1 inch) and i kno with soem aluminum heads the stock headerbolts dont work because the dont fit... will these fit? i was lucky enough to find a stock header botl in the garbage and it looked liek the bolt bottomed out with like a quarter inch of space. im using bbk shorties... will the 1 inch bolts be ok? yes right?

 

[Rick 91GT]

I find most aftermarket alum heads take the shorter bolts, believe they are 3/4"

 

[fox racer]

thats what i thought... but the stock bolt nealry botoms out... and i was told i didnt need new bolts, so im hoping this is ok

 

[fox racer]

worst come to worst ill grind them down as needed.

 

[Insane3D]

The FRPP aluminum Y and X heads both use the standard header bolt size that the stock heads do. They are 3/4" long, not 1". I saw some people suggest using 1" bolts, but I called Ford and they said they "might work". The BBK headers I just took off, and the FRPP ones I'm putting on both came with 3/4" long bolts.

You need to be careful with 1" bolts, if they thread in too far you can damage th threads I believe...

 

[hrspwrjunkie]

I've used both on X heads. 1" did work, but barely. They did bottom out, even with the thick header flange on a BBK header. I chose to go with 3/4" and was much happier.