Saw this on San Francisco craigslist.....This would give you the L31 Vortec heads and short block with roller lifters and cam, providing a far superior platform for what you want to do for the price of bare heads (400 bucks). You would want to strip the heads and have them magnafluxed for cracks at a local machine shop, though. I would try to make some sort of deal with the fellow contingent upon the heads being crack-free. Replace the crank and one rod and you'd be into an L31 long block for cheap.
https://stockton.craigslist.org/pts/...403181469.html
Here is a set of heads only. Again, make a deal to magnaflux 'em before you pay all the money....
https://modesto.craigslist.org/pts/d...382689320.html
Here's a set in Sacremento, same deal on magnaflux....make a deal with the owner
https://sacramento.craigslist.org/pt...399771238.html
There is no way to find a set of heads anywhere that will flow like the L31's for under $1000, so the best bet you have is to bite the bullet and purchase some used, then bring them up to fresh. Alex's Parts spring kit will allow more valve lift without any machine work.
https://www.alexsparts.com/valve-spr...rf-hyd-roller/
After exhaustive research, I found the cam that I would use.....
https://www.summitracing.com/parts/c...00-8/overview/
It says computer controlled because it is ground on a 112 degree LSA, so it is just perfect for a carbureted motor that is looking for additional manifold vacuum for use with power brakes.
Use these roller hydraulic lifters....
https://www.summitracing.com/parts/hrs-91164n
L31 heads will bring the SCR up to 9.4:1 and this cam will be just the ticket to match up. The Crane cam I was looking at originally was far too pricey, so I found this CompCam that will work even better, for less money.
If you were worried about the studs pulling up out of the head, here is an affordable solution that has been used by many fellows......
https://www.summitracing.com/parts/mrg-806g
P.S. Get the rail rocker arms and valve covers with the heads if you can. You cannot use guidelates without machining for screw-in studs and so stock L31 rail rockers are the cheap, easy solution.
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