How's that for some love? This forum is freakin' awesome......

 

Unless you're planning to spend $2k or so on heads...keep the vortecs and just do a cam upgrade

 

Crashdog172: I sent you a PM.

Are the Vortecs that good that you need $2k/pair heads to out perform them? What about $1k/pair heads like TFS23* or dart SHP or any of the other similarly priced heads? Are they not worth the money?

 

They're certainly good enough that you'd want to think twice about upgrading them with another Tier 1 head. Again - budget becomes the driver here...until that's firmly set, you'll have no way to make any firm decisions

 

Vortec heads are cheap and flow well. They are also Iron, lift limited @ somewhere around .470, and have small valves and ports, pressed in studs and can't accept guide plates. There are many heads that will outflow them for $1000 There are none better for $600. Iron heads are heavier and you need a bigger cam with a given compression to run them vs aluminmum. You can build up to 400 HP with stock vortecs. AFR is pretty much the best head out their but they are about $1400. If you have say a 9.5 to 1 buld with vortec heads putting out 350 HP a set of AFR 180 with a higher lift cam could make considerably more hp on the same build (425-450). This takes a cam change and head change because of the lift and flow limitations on vortec heads. It really depends on the level of build your going for and what compromises you are willing to make. Every build is a set of compromises. A 1 hp per CI build can be done relatively cheap and can run higher gearing. A 500+ hp build needs different gearing and internals and cost more per HP. You can go from 350 to 425 HP for not a lot more with better heads and cam.
Here is a flow chart that will tell you what the flow nombers are on most available heads. I don't think the Dart SHP are on the chart but the flow charts are available online.
http://www.users.interport.net/s/r/srweiss/tablehdc.htm
There are also some actual dyno comparisons for different builds on this page. If you go through them many are the same compression with different head, cam, intake and carb changes. It will help you understand what the changes produce.
http://www.ryanscarpage.50megs.com/combos1.html
The best street heads are the most flow with the smallest ports and vortecs are unsurpassed for their small port size. If you increase CI or RPM capability you need more flow and bigger ports to take advantage of the CI or RPM increase. If you are going sub 9.5 compression, 350 CI, want your power at the bottom end-midrange, are shooting for 1 hp per ci and price is the deciding factor vortecs are tough to beat. Vortec heads bolt on any Gen 1 SBC and any SBC gen 1 designed head will bolt on a vortec block. Intake bolt configuration, port size, max flow, available cam lift, rocker arms are differences in the heads.

 

Those websites were pretty neat, I went through all those combos, mind bogling really.

Would a stock M20 trans bolt up to the L31 block?

 

Yes.

 

Awesome, thanks everyone for your help! I have some more general engine questions but I will break it out into another thread.

 

Yes,but you will need the newer,correct flywheel for that engine.