TheDarkSideOfWill wrote:
1 1/4 is a big bar
Is there any kind of institutional knowledge of 308 setup that says that's a good idea... on the front end of a mid-engine car.
Admittedly, using the 308 style gearbox puts the engine 6 inches higher in the body than it should be, but I'd expect that to show up in the rear bar...
Notice its hollow though....1.25OD, .75ID making 30% more stiffness than a 1.125" bar not the nearly double a solid 1.25 would be. For sure its the stiffest I'd consider....but once the car is set up for these bars a new bar is $150 and maybe 30 minutes to install so changing my mind becomes easy.
The aftermarket solid bars came 1.0, 1.125 front and .75, .875 rear so I would say that is a good baseline for where most setups ended up back in the day and the 1, .75 combo is the hot street car setup as I understand it anyway.
The 1.25 hollow bars are available in .095, .125, .188, .250 wall. .095 is 17% stiffer than a solid 1", .125 is about 20% under a 1.125, .188 about 20% over the 1.125. All probably good options.
on the rear solid 3/4, 13/16, 7/8, 5/16, 1 are available as are hollow 1" OD with .095, .125, .188, .25 wall with .095 wall almost as stiff as a solid 7/8. Almost available are 1.25 bars that are gun drilled .75" and OD turned so only the bearing area is 1.25. they com with ODs from 0.91 to 1.25 on .030 steps.
Lots of options....which has me pondering quite a few variables including spring rates which also effect roll stiffness. I've seen a lot of talk about doing springs by frequency which leads to very different than normal 308 setup spring choices, like rear springs that are stiff than the front. That would cause MASSIVE oversteer without a MASSIVE front sway bar.....that seems wrong and why I ordered the new 600lb/in front springs that are 50% stiffer than the rear and should get the car near neutral steer with no sway bars....well, probably still a bit of oversteer completely bar less but close. I'm not sure this is right though as the point of springs is to hold up the car....which is what the frequency method is all about, use the spring to hold up the car and respond to bumps and that sway bars to tune roll stiffness. So much to think about.....