Pulling Forum - Naturally Aspirated Cubic Inch Limit???

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Naturally Aspirated Cubic Inch Limit???

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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=149391
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Topic: Naturally Aspirated Cubic Inch Limit???

Posted By: KevinON
Subject: Naturally Aspirated Cubic Inch Limit???
Date Posted: 12 Apr 2018 at 7:31am

We are in the final stages of finalizing rules for a new 7000lb Super Light Modified Farm class in our club here in Ontario. The quick and dirty rundown of the rules are, 330ci, 2.3 x3 charger, maximum of Bosch Model 100 rotary pump, 3100 rpm, no water. We are wanting to allow naturally aspirated tractors to run in this class as well, with one updraft carb. What maximum cubic inch should we allow, and what might be more important, what rpm limit? I value any and all comments. Thanks!!!

Replies:

Posted By: LFIFM45
Date Posted: 12 Apr 2018 at 7:46am

Around the Midwest the 360 3000 RPM classes are becoming real popular with a box 3lm turbo, 330 cubes seems a little low to me to get more tractors I think 360 limit would be better choice but to answer your question the SCWTP has a good class.

360 turbo 2.75 inlet 3000 RPM

650 cubes NA and less 5000 RPM

More than 650 cubes NA 3,000 RPM

This has only been in effect for a year but seems to be fair some tractors included are 88 Olivers , Farmalls with RD motors, Big cube MM and Case, Oliver with 5.9 Cummins

Good luck sounds like a fun class

Posted By: KevinON
Date Posted: 12 Apr 2018 at 10:30am

Thank you for the reply! That is good information. Do the NA tractors have to run any safety blankets, or side shields, etc? We have gone with the 330 cube limit to encourage some smaller cube tractors to come out. We have a class with a 410 cube limit that the 360's run very competitive in. Thanks, again!

Posted By: LFIFM45
Date Posted: 12 Apr 2018 at 3:20pm

http://www.scwtp.com/" rel="nofollow - http://www.scwtp.com/

You can check out the website above, they have all of the rules posted there. They do require safety blankets and are slowly pushing towards roll cages as well. The insurance company pushed for the 5000 RPM limit in the NA class. I forgot to say that they are limiting the pump to a rotary style pump on the turboed tractors as well.

Posted By: KevinON
Date Posted: 12 Apr 2018 at 3:32pm

Thanks! We are limited to a rotary pump as well.

Posted By: rowcropmafia
Date Posted: 12 Apr 2018 at 11:12pm

Based on my observation of being a part of a very similar class you can probably go unlimited cubic inch for the natural asperated tractors if you both run the same rpm. Makes for a very competitive class with a lot of variety

Posted By: KevinON
Date Posted: 13 Apr 2018 at 5:56am

Thanks!

Posted By: Acllss puller
Date Posted: 14 Apr 2018 at 10:11pm

Hey Kevin , way to heavy ! 6500-6700 lbs is more than enough with your cubic inch limits . Lighter tractors turn tires faster - faster equals better show !!!

Posted By: Acllss puller
Date Posted: 14 Apr 2018 at 10:16pm

Why no water ? Cheap power and insurance to protect motors . Your limiting pump ie you can't cool with extra fuel if you can't pump therefore need water inj to cool ! Just my 2cents I've been through this back in the day ! Lol ! 18x38 tires ? Cut ? 600 cubes na probably won't compete without extreme rpm , above posts probably make sense on na .