Bmod setup help

[dirtracer07x]

Already down to a 525 on rf. I'm thinking I need to run the rear end straight up. Not trail the RR.

[dirtracer07x]

Here's the plan for this week. Put a 550 in the rf, a 200 in the RR, run the rear end straight up, put a hold up shock on lr and lower jbar on frame 2in.

[oldtrackchamp4x]

You are planning on doing WAY to many changes on the car. You should only make one change at a time so you know if it works or not. If it doesn't work put it back where it was and try something else, if it works leave it where it's at and go from there. In reading your post that the car is good mid to exit, i would just try dropping jbar 1/2 inch on pinion or raising an inch on frame. JMO.

[dirtracer07x]

Should jbar be level or lower then pinion on 9in?

[oldtrackchamp4x]

As I said before, measure from center of bolt that attaches jbar to frame bracket and rearend side pinion plate bolt center wto the floor with all ride heights and tire pressures set. If rear end measures 6 in to floor and frame side measures 12 in to floor you have 6 inches of jbar split. Also as I said before, if car is good except for entry to middle, drop jbar 1/2 inch on pinion or raise frame side 1 inch. If the track is the same as the last time you raced it, you should feel the difference. JMO.

[dirtracer07x]

OK I backed off on all the changes I was going to make. Checked measurements and had 8 1/2 ins of rake. Lowered it to 6in and set rear end square. That's it for this week. Thanks for the help.

[oldtrackchamp4x]

Run the car as you now have it in hot laps, if you get hot laps, and see how it enters corner. If jbar is at center of pinion now and car is loose on entry lower it a 1/2 inch on pinion. If it is already 1/2 in below pinion go to an inch below pinion if car is really loose on entry, or raise a 1/2 in on frame if just slightly loose on entry. If you don't get hot laps and car is loose on entry in heat race the way you have it now and track will be the same in the feature or drier, raise 1/2 to 1 inch on frame or lower the 1/2 inch on pinion. JMO. Good Luck.

[dirtracer07x]

It was really good in hot laps on tacky track. In the heat it slicked off some so I lowered RR bar to level. Main was super dry and car wanted to spin as soon as I got back on gas at mid corner. Think I will lower jbar at pinion for next week.

[dirtracer07x]

Question. Is there an advantage to moving the RR spring on top of the rear end and if so what is it? Right now I have a 16" on slider behind but I see a lot of guys going to the 13" ontop

[oldtrackchamp4x]

Remember, jbar is for entry to center. Did you raise lr bar? Did you increase your lr bite? If not you should probably try one or the other. You can drop your tire air pressures to 12 on the right side and 10 lf and 8 lr. On dry slick you really need to be VERY gentle on the throttle, or you could try a vacuum secondary carb. Keep good written records on how the changes effected the car and how dry or tacky the track was so you will know what changes to make to your car when it is dry or tacky. Again, one change at a time. And finally be honest with yourself and think about how well YOU did driving the car. JMO.

[dirtracer07x]

What about putting a 2off wheel on RR? Now all are 3 offs.

[oldtrackchamp4x]

What are you wanting to accomplish? JMO.

[dirtracer07x]

Tighten car up mid corner on gas. I changed RR spring to a 200, raised RR bar 1 hole, lowered jbar 1 hole at pinion and the car was awesome.

[oldtrackchamp4x]

Remember to keep notes on what the track was like and the changes that worked on that type of track. Sounds like you are good to go now. Good Luck. JMO

[dirtracer07x]

What front spring rates are guys running with chevelle clips? I have 625Lf 525Rf was told that is to soft and should go 700/600. Thoughts?

[UltimateRaceCars]

I have customers on 500-550 and 600-600 and 600-650, it really depends on your driving style and the amount of grip/banking your track has. If you enter soft or have a flatter dry track you can go softer than someone who enters hard and or races at a tacky high banked track.