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Author Topic:   To change components or not to change?
mdsteacher
Member
posted October 22, 2004 11:07 PM
Mdsteacher, what class you running with this engine? We're running a typical setup to yours, excluding the cam, in a mod on a .3 and 3/8 mile track. Stock crank, 2-main block, dart heads (smaller runners?), oliver rods, 250cc hyper domes, etc. and turn ours 6800-7000 nightly. We're using the midwest motorsports #9 grind and this puppy screams from corner to corner in an older overweight chassis. For the bucks, the cam was a great purchase. Granted, the roller will still provide even more performance if you want to head that route. We thought about going to the roller next year, but we're content with the HP we're getting now. Hope this helps. Good luck.


Kromulous
Member
posted October 25, 2004 07:30 AM
Are you running alky or gas ? and how big is the track, sounds like a big 3/8 th's maybe.


mdsteacher
Member
posted October 25, 2004 11:01 AM
the #9 cam is actually set up for your size tracks but the power band is only good to 7200. with the smaller motor i'd switch to a #11 cam. i'd also keep the crank you have and spend the money on the smaller runner heads (215 or even 200cc) especially since your running gas. good luck!

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Kromulous
Member
posted October 25, 2004 11:45 AM
Small Runners and / or more compression will get you more torque. Although with the rods your running i wouldnt go over 12.5 to 1.

A Roller cam will make more power in general and maybe more torque if you select the right one. Only thing you need to worry about with a roller cam vs a flat tappet is bearings, push rod length & springs. Roller cams need more spring pressure overall vs a flat tappet.

More cubes would help as well, your heads on gas would be good for a 383 or 406. It may be a good idea to build another short block with these heads / intake to get what your after.

Just some ideas.

[This message has been edited by Kromulous (edited October 25, 2004).]

mdsteacher
Member
posted October 25, 2004 04:12 PM
too large runner causing low velocity. This low velocity kills mid range torque. Build bigger cubes or ditch the intake and heads. More compression will help a little but not much. You can change cams all you want with that low velocity but it will be to no avale. If you keep little cubes plan on turning 8 with that runner size and I don't think your gonna pull stumps off the corner anytime soon at 52 or 57.

Those heads work good with 419+ cubes.

mdsteacher
Member
posted October 28, 2004 06:05 PM
i'd go with the 200 runner. good torque and decent top end. 215 would be ok too but you'll hafta twist it more and you'll lose a little torque.

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