Chevy Nova Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
627 Posts
Discussion Starter #1 (Edited)
I am assembling a 350 and I'm a little surprised that I can't install the intake bolts.
Block was decked but I don't know how much. The flat top pistons (sealed power 345P) are 0.015" below the deck, so it can't be that much. I'm using a 0.027" thick head gasket.
If I remove the intake gaskets I can install the bolts, but with the gaskets installed, they won't go, but it's close. According to what I've read, if 0.015" is removed from the deck, then 1.2 x 0.015 = 0.018" should be removed from intake/head mating surface and also 1.71 x 0.015 = 0.02565" should be remove from the block mating surface.
Here's a few pics. I removed the rubber end gaskets and there is still 1/8" gap between the intake and block.
Holley Systemax heads and Edelbrock Performer RPM intake Fel Pro 90314-1 gskts.
I stood on the intake and the holes still won't line up.
To me it looks like I have such a big gap at the block/intake surface that I shouldn't remove anything there, which seems odd to me. I also am not sure how much to remove from the intake. Please let me know what you think.
398289

398290
 

·
Registered
Joined
·
627 Posts
Discussion Starter #2
Also, does anyone know the compressed thickness of the 90314-1 gaskets?
 

·
Premium Member
72, 2 Dr, 383, 700r4
Joined
·
1,365 Posts
I've never seen compression thickness specified on intake manifold gaskets as it is probably negligible. You will always see it on head gaskets because you do have compression of the rings sealing the piston bores.
 

·
Registered
Joined
·
1,093 Posts
ARe the head gaskets on in that picture? A picture looking down at the holes would be helpful. And no the gap at the intake to block is not large.
 

·
Premium Member
Joined
·
56 Posts
I've had to enlarge the bottom of the intake holes in two different EFI intakes I installed. The block was ZERO decked and had a .038 squish on the head gaskets. You could access your problem better with the head gaskets installed.
 

·
Registered
Joined
·
627 Posts
Discussion Starter #6
The head gaskets are installed and the heads are torqued.
 

·
Registered
Joined
·
627 Posts
Discussion Starter #7
I think the intake gaskets I'm using are 0.120" thick. The Edelbrock 7201 gaskets designed for the Performer RPM intakes are 0.060" thick. I'm going to get a set and try them.
 

·
Registered
Joined
·
140 Posts
The .120" thick gaskets are for oddball combinations of milled heads/intakes. Try the .060" ones, I think they will work for you.
 
1 - 8 of 8 Posts
Top