Destroked motor?

Ron Earp

Admin
Anyone think of using a destroked motor for a GT40? I don't know the specifics of how over-square one could get but it would seem that you could contruct a really high-revving power plant.

Three and four cylinder cycle engines (and a lot of modern twins) are typically over-square and are a lot of fun because of it.

I know that Gordon mentioned he has 7000-8000 RPM 302s available as do other shops/builders. I wonder to what extent one could get to with a really short stroke and std bore in a small block Ford? I'd image cylinder filling at high RPM could become a problem at some point since we're largely limited to 2 valve heads (although years ago there was a four valve head prototype in Super Ford).

Purely academic for me as my choice is decided. But it was one of the first options I thought about months ago and wondering if anyone has pursued or carried out this option.

Ron
 
4 valve heads....
I'm putting a 351C in my GT40. I follow the Pantera websites somewhat and noticed some talk recently about 4 valve heads for Boss 302's and 351C's. The website also lists heads for other Ford and Chevy motors. http://www.araoengineering.com/
Since my engine is about complete, I don't plan to persue anything like this (at present anyway!). I haven't priced them but have read that they are expensive.
 
Ron, We have experimented with destroked 351's down to 310 cid. In a full race configuation the hp is 775hp and 400lbft of torque. peak hp is reached at 7800 rpm's and the curve is flat to 11,000. Peak torque is reached at just under 6000 rpm's and is flat to 11,000. You can shift this motor at 9500 rpm's on a regular basis and run it 10,000 if you need to. This engine is also very linear, meaning you can get very hard in the gas and the engine pulls very evenly making it the perfect road race engine. We are currently building a 306 that has almost the same torque and hp numbers and will be shifted at 9000 rpm's. It should be interesting. The biggest thing to make an engine work like this is the heads. If you put enough head like a Yates or worked Victor SR these numbers are possible. An engine like the 306 in a GT-40 would be a 220+mph race, (hint,hint).

[ September 22, 2001: Message edited by: Gordon Levy ]
 
Back
Top