2.4 W/ 2.2 High Compression Mod

[jluetjen]

Chad; Are you going to dyno you're new engine? It would be great to see how the two different versions of 2.5's compare, even though it sounds like they'll have different cams and valve sizes (both of which will make a bigger difference then the stroke in the engine's performance I suspect).

[Plavan]

Yes, that is the plan. I want to see the difference too. My short stroke 2.5 has a GE80 profile cams with stock 2.7 valves. So there will be a difference. I do not rev the short stoke over 7.5K (although it is good for 8.3k to 8.5K) My thoughts are to take advantage of the long stroke torque at the lower RPM's since I do not rev the short stroke all that high anyway. I am going to keep the stock exhaust valves, but bump the intakes up to SC valves. I am enlarging the intake ports and exhaust ports a few mm. The GE 60 cam will allow me to use the bigger intake valves, with a little more grunt in the lower RPM's.
Should be fun . Not that there is anything wrong with my current setup.

[Cire]

So if I want low end torque (off Road car) do I want a 2.2 that is punched out to a 2.4 or do I want a 2.4 that is converted to a 2.5?

So many choices...

Thanks.

Eric

[bkreigsr]

how about a custom cam grind, where you specify the torque curve? 2.2, 2.4, 2.5 can all be made to pull at low-end.

[jluetjen]

Eric. more cc's equals more torque. In general terms it's that simple. Where you put it in the rev range is a fuction of the specifications of your engine -- specifically the cam spec's. In regards to that subject, I put pretty much all that I know into this thread.