Imca..mod specs?

[92modracer]

Hi please bear with me on this.ive been reading the imca rules on modifieds on imca web site. Kinda confused on engine specs? You either can run a crate engine or build your own right? So the cubic inch rule is? When you build your own? I understand steel heads and flat tappet cam. Everything else is kinda confusing to me.. sorry for coming accross dumb. Please help thank you

[stock car driver]

no limit ...........

[MM90]

Steel heads, flat tappet cam, no titanium, no stud girdles. Otherwise it's basically up to you.

[7uptruckracer]

My word of advice is be careful how big you go on tracks with low traction big CI look great on a dyno but they can be hard to drive.

[RaceMentally]

Have a high hp motor please. The bigger the better!!! Everyone should run an open motor. Minimum 585 lift.

[92modracer]

I really apreciate your thoughts and opinions alot. Just wasnt sure on what i was reading in there rules. I also do understand to that sometimes bigger isnt better and also sometimes slow is fast. Thanks guys

[dereksehi]

If I where to build one for myself I would build one that performs like the crate but with a little more power to be the best of both worlds. Don't go bigs cubes or a tight lobe seperation as in 106 open it up to 110 or 112 this is what helps make the crate so driveable. I would keep the compression around 11:1 for reliability and use decent set of heads with 200cc runners. Avoid extremely lightweight rotating parts and keep the rpm around 7000 this will help the car hookup in the dry also.

[clbaker25x]

If I where to build one for myself I would build one that performs like the crate but with a little more power to be the best of both worlds. Don't go bigs cubes or a tight lobe seperation as in 106 open it up to 110 or 112 this is what helps make the crate so driveable. I would keep the compression around 11:1 for reliability and use decent set of heads with 200cc runners. Avoid extremely lightweight rotating parts and keep the rpm around 7000 this will help the car hookup in the dry also.I don't understand why the thought is to limit RPM. I think that would be the key place to take advantage of the crates.

[dereksehi]

You would still be running 600 harder that half a point deeper with more power that would outrun the crate in the tack but still be driveable in the dry if you want to run harder in the tack just change gears and run it harder.

[dereksehi]

The reason the crates work so well is hoosier g60s won't hold a 600 horse engine maybe the 450 the crates are putting out is all they will put down. Plus with the crates only runnin 6400 they don't have a lot of gear in and that takes the initial snap out of the car that busts the tires loose and the mild cam make them driver friendly some of these engines almost have to much power!!

[clbaker25x]

I know for my driver he preferred to back pedal more gear as it shuts down the engine faster once you break traction. While it was probably a little harder for him to keep traction he felt like the higher gear was easier to peddle on the slick.

[RaceMentally]

Wish the crate was never introduced in this world of racing.

[langdonracing48]

My word of advice is be careful how big you go on tracks with low traction big CI look great on a dyno but they can be hard to drive.7up is absolutely correct. watch the power because it's not gonna hook up very well in an imca mod, especially on a slick track. i run a UMP mod, but i usually run 355's, i dont run a light rotating assembly at all, and i keep my rpm range to 7200rpms. hooks up a hell of a lot better than a lot of the 421's and 434's i race against. a lot of my motors ill use a stock cast crank(48lbs), i beam, usually scat 5.7 rods, trw/speed pro 11:1 forged pistons(311$ a set new), i run a 215 cc runner head with 2.05/1.60 valves, amd i run COMP Cams 12-688-47. it's on the small side, but i get off the corner hard and it'll pull hard to 7400 rpms. gives me a wide variety of gear to play with. i run on a very slick 3/8 mile track in southern michigan. i bounce from a 5.67 gear(7200rpms), all the way down to a 5.14 gear(6300rpms) and have very good luck with it. im very much a budget racer but i have really good luck with this set up. plus i run steel dart heads so i can run the motor in any class i want to. good luck with whatever you choose to do. if you build a hog, gear down a ton to hook it up.

[dereksehi]

I don't care for the crate deal either but they have proved you don't need a 600 horse engine to win a modified feature at least in IMCA due to the tires. They have shown you don't have to spend a lot if you know what you're doing with an engine it's more about hookin it up rather than pure power.

[RaceMentally]

I don't care for the crate deal either but they have proved you don't need a 600 horse engine to win a modified feature at least in IMCA due to the tires. They have shown you don't have to spend a lot if you know what you're doing with an engine it's more about hookin it up rather than pure power.It was a lot easier to win before. Now it takes the driver out of the equation a whole lot! Along with the testing and actual engineering we've done for this crate to come out. We've been running mild motors with no more than a 520- 550 lift cam and that was even too much. But everyone loved trying to build the biggest baddest high Hp "Drag Racing" motors they could. I personally don't like the crate because I do believe it enhances a less talented driver. I still tell every driver I know to get a big motor built and will continue to because it makes one less person to worry about on race night. More Hp than tq and the most compression and cam I want them all to have.