I'm getting ready to start building a pullin truck, and will be starting with the motor, and then building the truck around it. I would like a 12 valve block, but I would also go for a 24 valve. I have found a couple of pretty good deals on some new Common Rail shortblocks and it got me wondering. Are the 3rd gen motors the same as the older ones, other than the injection system? I will be taking the motor down to the bare block anyways, but was wondering if the main components, (block, crank, rods, pistons, etc...) were the same? Thanks.

Eric

 

IIRC, the 3rd gen blocks no longer have the hole in the side to run a mech lift pump.

 

the oiling/cooling passages are also slightly changed, so a common rail block wont accept a 12v head

 

Common rail block is a whole new animal. If you want to run inline stick with the 2nd gen type of block.

 

Authough the CR block is rumored to be stronger and it comes with a girdle, and can be machined to accept cam bushings/roller cam. Also the side cover of the others is just another place to blow oil out of. The fact that the block isn't machined to accept a mech lift pump shouldn't be an issue for a competiton engine (since they won't keep up with demand anyway) and the CR block will accept a 24v head (no pressed in valve seats). Also just like the 24v they can be p-pumped as well.

 

So if the CR block will accept a 2nd gen 24 valve head, won't it accept a 12 valve head? As far as I knew the 12 valve heads and the 24 valve heads were pretty much the same as far as bolt pattern and such. Thanks.

Eric

 

Yes a 2nd gen 24v head will work on a CR block with no modifications.

 

Just bit the bullet and called and talked to Scheid's today. Was told that they run the ISB blocks with 12 valve heads, so I'm in the clear I guess, lol.