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ride height
07-25-2015, 01:12 PM
Were in our first year of B Mod. Car handles great and all. We run 2bbl spec motor and cant seem to get the takeoff speed that a crate does? Is that typical of this motor or what? Im not a motor guy. We ran the spec because it was cheaper to do for us at the time. Its a nice motor, but seems the crate has more nuts. Is that that true typically?

Dirtmod13
07-26-2015, 09:52 AM
No, crate is rated at 350 horse, some of the motors from the better engine builders are nearing 400. But obviously a stock 350 with stock heads and the wrong cam will not help. Ask one of the local engine builders for a quote and list what parts they are using and try to mimick that combo.

hatchet
07-26-2015, 11:44 AM
We run street stock with a built motor with a 2 bbl. . The crates motors have more torque (bottom end) than a built motor . They jerk out panties down on the start .We re degreed the cam got the bottom end to pull with the crates but lost top end pulling . We are going to change the cam this week . Its very hard to get perfect combo (carb. ,heads ,intake , compression ,cam) .

bob75
07-26-2015, 12:55 PM
Crate. Crate. Crate, never thought they could out do a. Open 2 barrel motor but I was wrong, very drive able, they will out run a legal 2 barrel motor.

DaveBauerSS6
07-26-2015, 02:19 PM
Were in our first year of B Mod. Car handles great and all. We run 2bbl spec motor and cant seem to get the takeoff speed that a crate does? Is that typical of this motor or what? Im not a motor guy. We ran the spec because it was cheaper to do for us at the time. Its a nice motor, but seems the crate has more nuts. Is that that true typically?

Is there a gear ratio rule.
Is there a RPM chip rule?

bob75
07-26-2015, 04:17 PM
602 crate 6200

hatchet
07-26-2015, 07:10 PM
There is a guy in the nesmith street stock class with a 602 that turns 6800 rpm . Last year we had a built 2 bbl motor we turned 7800 to 8000 every week every lap . Won 6 in a row . The crates would pull us two cars on the start . Built a new motor with a 2 bbl cam . It will stay with them on the start now but has no top end . Thats why we are going to change cam and try play with degreeing it in to try to get the best of both bottom end and top end . We know these are cheated up crate motors . We are pulling a 6.83 gear and they are pulling a 6.50 gear .We have faster straight away and corner speed than they do . Our handicap is we wt. 300 pounds more than they do . We are faster down the straight away and the corner after we get going . The crate motors should have to run a chip 200 rpm more than the nesmith max rpm rating supplyed and installed by the track tech with some kind of special tamper proof tape .