building for torque
 

so, I have a 89 305 roller block that im wanting to build for a project, and I want as much torque as I can sanely get out of it and it live. I have a MAF style TPI that I want to run.i have a set of "416s" that I want to port.id like to have forged flat tops too BUT my question is what would be the best cam for high torque production?? im gonna balance it maybe but ill have a 5000 rpm limit anyway. will a forged 350 crank fit?? :thanks:

Re: building for torque
 

Build as much compression as you can, use as long a rod as you can, as flat of a piston as you can, as much head flow as you can get with a small runner and cam it for the lower RPM range and if you're really wanting to go for it - install a 3.75" stroke crank and gain about 20 CI of displacement and a long stroke/small bore will generally make a little more torque.

Re: building for torque
 

350 crank is the same as a 30Y crank but is balanced differently.

Re: building for torque
 

Build for dynamic compression, not for 12:1 static compression. And stock rods will be fine. HR cams allow short duration with high lift, which does great things for torque. Adding 1.6:1 roller rockers will also do great things for cylinder filling without adding duration.
But if you build for power, you can get the torque back with axle ratio and torque converter, if automatic.
Either way, I'd go with the TFS 175 heads, and a shelf cam doesn't exist for how I'd do it. The XFI 254 has too much exhaust duration and too wide of a lobe separation, for low-RPM torque. Late exhaust openings really help low-end. But having overlap at 0.050" hurts low-end, so be careful.gl

Re: building for torque
 

Get a 350 block.

You WILL make MORE torque & HP for less money

Good Luck !

Re: building for torque
 

torque is the result of three major factors
displacement, cylinder pressure and volumetric efficiency, a TPI intake is designed to maximize efficiency in the 2500rpm-4000rpm power band (depends on cam timing heads,,displacement etc.)
http://www.grumpysperformance.com/volumetric.gif
the suggestion to buy a 350-406 short block, build it with a 9.5:1 compression ratio, and match it to a set of TRICK FLOW 175CC heads, so you can use that TPI intake with a cam similar to this, with 1.6:1 ratio rockers on that TPI will produce decent mid range torque, you might want to think of it this way, if a sbc engine makes 1.2 foot lbs of torque per cubic inch of displacement a 307 would produce about 368 ft lbs of torque, but a 383 would produce 460 ft lbs

http://www.cranecams.com/product/car...detail&p=23941

http://forum.grumpysperformance.com/...umetric#p35188

http://forum.grumpysperformance.com/...php?f=52&t=401

Re: building for torque
 

Then you can figure out how you're going to plant that to the ground.
That's also a fun part. :thumbsup:
I re-built a 10 bolt but I doubt that will work for you.