20psiofevil
Active Member
- Joined
- Feb 10, 2013
- Messages
- 628
*Warning this is a ford v6 in question but you guys have the greatest turbo v6 tech on the webz and plethora of turbo v6 information and this is why I post tech questions here. Also because you'll have that guy Bison among many other greats!
Mainly it's just the 60' but for some reason I cant get the car to 60' like it did last year. The best with the new turbo has been 1.41 and previous was a 1.29 with several 1.3's last year. The 1.29 was with a borg s366 88ar open t4 3100rpm launch 10psi and the turbo on the car now is a cast 70mm p-trim 96ar and 3400rpm launch 12.5psi. I'm not seeing any tire spin as I only go when there is good track prep.
I just cant wrap my head around the physics of whats going on here. The shaft of the 70mm is much lighter than the borg unit including the smaller turbine. Is it possible momentum and leverage of the heavier shaft/wheel are what made the s366 hit harder, or could it be the 96 ar t4 is just to big? Should I try to launch the car higher with the 70mm? Shift rpm is 6500rpm.

Mainly it's just the 60' but for some reason I cant get the car to 60' like it did last year. The best with the new turbo has been 1.41 and previous was a 1.29 with several 1.3's last year. The 1.29 was with a borg s366 88ar open t4 3100rpm launch 10psi and the turbo on the car now is a cast 70mm p-trim 96ar and 3400rpm launch 12.5psi. I'm not seeing any tire spin as I only go when there is good track prep.
I just cant wrap my head around the physics of whats going on here. The shaft of the 70mm is much lighter than the borg unit including the smaller turbine. Is it possible momentum and leverage of the heavier shaft/wheel are what made the s366 hit harder, or could it be the 96 ar t4 is just to big? Should I try to launch the car higher with the 70mm? Shift rpm is 6500rpm.
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