400 crank question?

[Vtec]

I am curious to know if this would make a difference ,I got a 350 with 10.5 to 1 pistons,194 closed port heads,264 - 214 camshaft and am wondering if it would make much difference to put a 400 crank into it?

[rwvjimmy]

Well if you get a custom crank made up for it you'll get a but more horespower, but mostly a massive improvement in torque. The displacement becomes 383 CI. From what I understand they don't last as long as a stock or forged 350 crank

[Vtec]

wow this has to be the slowest replying forum I have ever seen lol. Anyway thanks to all that replyed.

[Rowski12]

I have a 383 stroker in my 69 GMC 1/2 ton and it is a great torque monster. I have a compcams Exreme energy cam 268H I think. It had been running for 3 years now and is still going strong and I used it for a year or so for work where I would pull loaded trialers on a regular basis. I have had no trouble with it. The only thing with the stroker is to VERY carefuly calculate your compretion ratio. Mine with 12cc dish pistons, closed chamber heads (68 cc) and head gasket was 10.2:1. But the cranking compretion was 205-215 pounds. Which is to high for regular pump gas. I have no trouble with reliablity and my crank was a 400sb with the mains turned to fit a 350 block. It has been great and when I finish the restoration on the truck I will definatly stay with the stroker.

[dracer398]

Don't forget to change your pistons too to compensate for the extra stroke. The pin heights are different.

[Rowski12]

Also with the different pin hieght on the pistons also need extra clerance on the connecting rods on the bottom of the cylinder bores and the camshaft if you have a high lift cam. The rods and rod bolts need extra attention if you are thinking of hitting higher revs because of the extra centrificale force on them from the .25 inch stroke. The fly wheel or flex plate need to be taken from sb 400 as well, because the 400 crank is external balanced and the 350 is internal balanced. They can be mixed up because my brother inlaw mixed them up (I think and man does it make for a bad vibration).