Originally Posted by ardmsrt
Hello Rod Buddies. Well, here is my first post. I want to see if this is possible on hot motor build sbc 4" bore. Plan on running 480 lift solid cam and 110 petro and 3600-4200 stahl. Would like to use L98 aluminum heads (10088113) on my sbc with Wiseco dome pistons. .035 mls gasket and 3" stroke. Setting the head on I see the dome pushes against the structual rib that's by the spark plug hole inside. Can I grind the rib down for clearance and not worry about structural damage to the head. I have cast heads also, 375 F.I. and also 882's that will probably fit fine. I think I know I'll have high compression motor but don't know exactly how high. I've never used an aluminum head and would like to try this set-up if it's possible. Any help would be greatly appreciated.
These are a pretty small chamber head like 58 cc's the factory used a.053 inch thick gasket with them. You need to find out just how high this compression is. I gather this a 302 4 inch bore 3 inch stroke. Actaully getting to the compression ratio starts with the cam and running calculations that drive out a Dynamic Compression Ratio in the range of 8 to 9:1 which drives out the higher Static Compression Ratio (SCR) once you have the dimensions that make this happen you can select the parts that make the needed ratio.
When you say the dome contacts the structural rib by the spark plug, the only thing I could see being called a rib by the spark plug on this L98 head is the spark plug boss itself. This is an essential part of the combustion chamber design that is intended to catch the wet fuel flow entering on the long side of the port and remix it with the air entering the cylinder so there is a homogenoius and burnable mixture of fuel and air.
I'd like to know more about the cam from the specs on the timing card. .480 inch lift doesn't strike me as all that much so I'm wondering about the super high stall converter and whether the cam really warrants that much stall. Although I have to admitt to thinking that on a 302 that cam will react as if it's bigger than it would on a 350 or 383, so maybe!