Chassis dyno..tranny
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Chassis dyno..tranny
Thinking of chassis dynoing a oval track car..400 HP at crank....is there a difference in final HP between a 3 speed Saginaw and a 4 speed muncie ?? Thanks
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Re: Chassis dyno..tranny
Any hp difference seen in such a test will fall with in the normal range of the dyno's accuracy I would say.
I would be more concerned with which transmissions gear spread would sever you best, and even then that would be trumped by which trans is likely to hold up and finish the race!
I would be more concerned with which transmissions gear spread would sever you best, and even then that would be trumped by which trans is likely to hold up and finish the race!
Last edited by mag2555 on Fri May 29, 2020 12:01 pm, edited 2 times in total.
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Re: Chassis dyno..tranny
It will depend on rotating mass. If they are doing it right, they will make all pulls in high gear. Take both transmissions on the bench. Put both in high gear and turn them by hand. Does one turn harder than the other? If so, then yes, it will show different numbers on the dyno...change your tire pressure, it will as well because it can affect tire slip on the rollers.
How well tuned is the engine already? Is the 400 hp an actual dyno figure or just a guess?
How well tuned is the engine already? Is the 400 hp an actual dyno figure or just a guess?
Mark Goulette
Owner/Driver of the Livin' The Dream rear engine dragster
Speed kills but it's better than going slow!
http://www.livinthedreamracing.com
Authorized Amsoil Retailer
Owner/Driver of the Livin' The Dream rear engine dragster
Speed kills but it's better than going slow!
http://www.livinthedreamracing.com
Authorized Amsoil Retailer
Re: Chassis dyno..tranny
Testing on a 248 Dynojet, the most critical part is to have matched rear tires. Knuckle dragging dirt-track guys show up with 3inches difference in diameter after being educated beforehand on the outcome. Locked differential , 3inches difference in tire diameter , and it makes a low rwhp number. No shit.
Re: Chassis dyno..tranny
In high gear the power is straight through the main shaft on both transmissions..Power loss differences should be minor
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Chassis dyno..tranny
Yes l heard of guys taking gears out..but our tech guy checks..l will get to trannys and compare them on the bench first..thanks