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ambonci21
10-06-2016, 06:35 PM
Got a 07 Hoffman. The car was hit in the LR and LF a few years ago. put a new frame horn on the lf. we have not resquared the rear in the car since that. have won 3 races like that but its always loose. I called Jerry last year for bar lengths and he said the tube lengths but not overall. he said to measure from grease zerk to front of axle tube on each side and run the LR 5/8 shorter( seems like a lot of lead to me). So I measured it like that and it was 1" shorter left side wheel base. all makes sense why the cars so loose. I could only get to 3/8 inch lead (was trying to get to 1/4)and it seemed like I was going to run out of heim(which tells me the cars bent or that is not a good indication of squaring the rear) we want to get it right to start next year. so my question is: what is the best way and easiest way to square the rear? also is it good idea to measure from grease zerk to axle tube? I know they build lead into the car and some turn the front stub. any input would be appreciated. Thanks

Dirt_Buster
10-06-2016, 09:12 PM
Why don't you shorten the right side?

oldtrackchamp4x
10-06-2016, 09:42 PM
I never measured from the grease zerk as I didn't know if the stub was turned or bent so I measured from the mid plate. I put on a new front clip last January as I knew mine was bent.You have to clamp a sturdy straight edge to the mid plate on both sides so you are measuring straight back to the axle tube as close to the tire as possible. Once you get the measurements you want, then just pick a spot by your four link brackets to measure to and that will make it easier to check when making changes on the rear end. Hoffman should be able to tell you if the stub is turned or not. I put one inch longer tubes on, as I like plenty of threads in the swege tubes. Make sure you measure and write down how car is now, in case you don't like it you can change it back. JMO

a25rjr
10-06-2016, 09:49 PM
Theres nothing wrong with doing it that way. You just need to have your frontend set correctly,as caster affects wheelbase, and rearend is in the chasis builders suggested location.

Drop a plumb bob off the front zerks and using a chalk line, snap a line perpendicular, front to rear, in the center of that measurement. Then you have established your chassis center line and can set rearend side to side. Drop a plumb bob off each side of rearend,same on each side, then measure from the zerk to each point off the rearend. I always measured rf to lr, lf to rr.

Racer96m
10-07-2016, 01:11 PM
I always go off the mid plate, only way to get a solid measurement. I have had many lower A arms bent very slightly, so that would throw everything off. I put the car on setup box's and drop plumbs from the plate and forward side of axle tube to do my measurements. How much lead you need? Depends, but 5/8th isn't what I think is a lot.

Dave

oldtrackchamp4x
10-07-2016, 02:28 PM
I agree. JMO.

a25rjr
10-08-2016, 11:14 AM
Sine you've wrecked it, I would ask the chassis builder where the lead is built in.....in the front stub, rearend placement, or both, and then measure accordingly.

powerslide
10-10-2016, 12:58 PM
I'm not sure it matters that much, Mid plate, grease zerk, tab on the overslung, 4bar bracket, whatever. As long as you are doing it the same every time. I would think measuring the grease zerk has more chance for error w/ a bent control arm or lower a-arm mount. Maybe take both measurements and record and have a good way to come back to if you think something is bent or you start running bad.

My opinion, you had 1in the way you measured and state the car is always loose. Close it up 1/4-1/2in and go try again, that should be a noticeable change. Numbers are just a starting point don't worry about being so close to the baseline, do what the car tells you.