Best engine combination with these rules for oval track racing

[mikey531]

We are trying to come up with the best engine combo within the rules to find an advantage. We just built a steel head 355 and it is making good power but we have several different combinations to choose from. The engine rules are here.

http://www.themodifiedracingseries.c..._Rule_Book.pdf

They start on pages 7 to 12 and pages - 31 - 34 I don't know if an aluminum head or an 18 degree or 23 degree will give us what we need. We would like max torque around 4000 with a peak HP at the end around 8000 we race on a 1/3 mile oval Thanks

[DanStokes]

As a Land Speed racer I'm no help at all. Deaf Bob may have some ideas but he's demo derby guru - not sure if any of the other folks have done this type of racing. What I know for sure is that in order to win you have to finish so I'd make durability a top priority.

Dan

[Deaf Bob]

Using a former 350 oval track motor that had to be de-tuned for demo derby.. Smaller cam and intake.. Still needs E85 or race gas.
Don't know the cam specs as we did not get a cam with the motor.. Supposedly dyno'd in the 700 hp range. Internally it has been smoothed for oil drain back. It still does the job and sounds awesome roaring across the arena

Sorry I could not be of more help..

[383gta]

We build a lot of oval track engines. The key is big bore short stroke. Stroke usually works best around 3.300 sometimes less. The key is big hp low torque. Low torque means you can get back on the gas quicker in the corner without spinning your tires. 18 degree heads if you can run them would be helpful. Most of ours end up around 360ci. But keep in mind we start with a 400 (style) block.

[fatguyzinc]

yikes...restricted to a 390 carb?!?!!!
that boggles me--i have no idea how to work around
that cam wise. how do those motors even
run choked out like that? astounding that the 'guys
that do it make that much power on that big of a
stumbling block....

[Dan Barlow]

Must have loose carb studs and a bad card gasket to suck more air around the base of the carb !

[Thumpin455]

My solution would be non standard, run a much taller gear than the chevy guys, could have lots of torque and still spin, but not to 8000 (won't need to anyway), and would probably win enough to get banned. Thinking along the lines of 1960-62 Nascar winning/dominating engines that had a 4" stroke and 4.12 bore, but with a 4.15 or 4.18 bore, 14 degree heads with 2.11 intake valves, and air gap intakes.

67-74 400 block. Forged 4" crank with 3" mains, Eagle 6.8" long 2.2 journal rods, KRE high port heads, and to freak out all the chevy guys an RPM dual plane intake, but a Torker II would work. The cam would depend on how much the heads flow and if you can have solid rollers or are forced to run flat tappets. Take advantage of that tiny carb restriction and instead of making high end power, make lower end grunt (lower end being 4000-6500 rpm). Run a 3.73 gear behind it instead of the usual 8000rpm 5.xx something gears the chevy guys gotta run, and move the weight around so you can nail it coming off the corners. That engine won't give a damn what the car weighs, so you could run a heavier car than the sbc cars and beat them. But building it means they will outlaw it once you start stomping mudholes in the sbc asses, meaning when you learn to drive it different. Also it would be 428-434ci, still small block territory, and they'll whine its a big block, but Pontiac only had one block.

Right now your chevy thinking mind is going, no, that wont work. Have seen it work, even with the 350 blocks and the 3.8 bores.The problem is most guys try to make a Pontiac run like a chevy, deep gears, long duration trying to wind it to 10,000rpm. Doesn't work that way, do it right and you will win. Fireball Roberts, Mickey Thompson, and many others, even Smokey Yunick did before they banned them, they all made winning race cars without the crappy little chevy engines. For what an 18 degree headed engine will cost you, you could do the 4" 428-434 with high end heads easily, unless of course you get your parts through a speed shop instead of one of the Pontiac vendors.

If the 351C isn't banned already, and the Windsor bottom end with 4V Cleveland heads isn't banned, that would be a great way to get around all the BS, but once again the chevy guys will whine and cry when you beat them.


Yeah, I already know you won't do it. But that is how I would do it if I wanted to turn left and bump into things.