[darom]

Hi guys.
I am putting together a 454 engine with a stock GM non-egr intake. The engine is circa 1974-76, oval shaped heads. The gaskets are FelPro 1212. What do I need to do with those circled water passages? Are there block-off plates?

Also, I checked the specs for the bolts - GM names 12 3/8 x 1 1/4" and 4 3/8 x 1 3/4" bolts. All 16 mine seem to be 1 1/4" length. Which intake takes 1 3/4"?

Thanks,
Den
'67 Camaro RS

[BBCMudbogger]

Its the heat crossover. Does the gasket cover it up? I don't think there should be any coolant in it.

[darom]

Yes, FelPro gasket covers that opening up (just for visuals, of course).

Do you know which bolts I need to use for this intake?

Thanks for your help!
Den
'67 Camaro RS

[machine shop tom]

That's not a water port. It is an air gap that acts as a heat dam.

tom

[darom]

Excellent, thanks!

Tom, do you know if I need to use 1 1/4" long bolts or 1 1/2" for the intake? I just checked summit and SDPC web sites looking at their intake bolt kits and they list both sizes.

[machine shop tom]

It would depend on how thick the manifold is at the bolt holes. I've never measured them, just picked the ones that fit .

tom

[Bumpstick]

Normaly with a stock type intake you use the 1 1/4" bolts in all the holes except for the upper 4 which do take the longer 1 1/2" possibly the 1 3/4" but as Tom said "pick to fit"...

BTW with an alum intake it would be the 1 1/2" & 1 3/4" (also I would use washers on both the stock and alum) Make sure to use small outer size washer...

[darom]

Thanks for the advice! - I will get 4 3/8 x 1 1/2" bolts.