Quote:
Originally Posted by Blue Rat
Those 781's will work. But they will need bigger valves an some work done to the ports. Here is a good web site with flow numbers. You could probably get a good set of aluminum heads that flow around 280-290 for a little more than the 40 year old castings that you are going to sink a hunk of money. (This my last edit) Stay with oval ports.
http://users.erols.com/srweiss/table...hevy_Big_Block
The camshaft needs to be on top of the game for something like this for sure. You really need to wait until the heads are done so you can give who ever the flow numbers an your other info about your truck. The camshaft needs to be designed around your truck parts list. You need to decide what the Compression ratio, converter, rear gears, headers, head flow numbers, intake an headers are going to be before calling whomever. If you go solid roller that is a whole new topic. We will save that if discussion for if you go that route.
I used http://www.straubtechnologies.com/ he is not cheap. Last time I ordered from him he used Bullet cams.
If you have not figured out by now. The tranny will have to be a good one. The 400 turbo will work, I would not use a 350 turbo behind this engine if you go the direction you are headed with the engine. A set of 3.73's would be nice too. |
Aftermarket heads will flow in the 340cfm range. 280-290cfm from 781`s is pretty easy to get but you wont see 600+hp with those numbers. Out of the box Brodix 270cc oval port race rites flow in the 340cfm range and can be had for about $2000 ready to go depending on where you get them.
Pick your heads first, then your camshaft. Brodix and OEM heads will need about a 12 degree split because of the exhaust port. AFR heads can use a tighter split or even a single pattern cam because they have a better exhaust port. Compression isnt as important as matching the cam to the rpm range and what the heads flow.