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dfhotlm33c
05-24-2011, 06:45 PM
This is an '02 Boss chassis. This is supposed to be a copy of a Mastersbilt car, but I am not certain if it is a copy of the "wide/combination" car, the "narrow" car, or the "smackdown" car of 2002. Thus, I am not certain the best way to locate the rear end.

The car originally had a short straight panhard bar mounted on left side of pinion..I installed a j-bar, middle hole on right side of pinion and 7.5" up on frame.

I was told by one person to set it up so the right side 4-bar rods appear parallel with the frame rails. Upon doing that, I noticed the left side bars appear at a relatively severe angle, in the range of 15-20 degrees from parallel to frame rail.

Currently I have some distances:
back of left rear rotor to outside frame rail: 7" ;
back of right rear rotor to outside of frame rail: 4.5"
distance from 90/10 plate on top of rear end to inside of right frame rail: 18"
distance from back of left rotor to center of shock mounting point on left birdcage: 6.5" (This seems short compared to some setup sheets)


Here are some suggestions I have heard..which should I go by?
-Make it so distances from each rotor to frame rail are the same (In this case, that would be about 5.5");
-Leave it so the right side bars are parallel to frame rail, and relocate left side birdcage inboard so the shock mount is more like 7.5" from rotor (The brake rotor bracket on the left side is part of a clamp on bracket separate from birdcage so this is possible..the right side brake rotor bracket is welded to floating part of birdcage);
-Align right side front and rear hubs (Make them equidistant from string line placed parallel to frame rail away from car);

I realize lateral location is important for weight placement, but am not certain how to approach this as I am not certain what setup sheet I could use to make that happen.

Thanks for your help

D

MasterSbilt_Racer
05-24-2011, 07:00 PM
What are the axle lengths for your rear?

dirtdodger
05-25-2011, 03:22 PM
should be in the ball park of 16 inches give or take a quarter to half an inch or so from plate on rearend to center of RR frame rail. I would say. call mastersbilt and tell them you have an 02 and ask them i would also ask the measurement on an 01 in case it was copied off that

dfhotlm33c
05-25-2011, 08:07 PM
Masters,

Just got back from shop...did quick measure..looks like we are running 36 Right and 32 Left...

MasterSbilt_Racer
05-25-2011, 08:49 PM
With a 32/36 rear, if the rear clip matches a Smackdown, then you should have 16.75"from 9010 plate to the CENTER of the rr frame rail. I'm not sure that is likely because you would be around 2" off right now.

If it is a narrow car, the rotors should be equal distant from the frame rails.

JAMESGANGRACING
05-25-2011, 10:29 PM
How wide is the rear clip where you are measuring the location? that will help determin what car it is copied off of.

dfhotlm33c
05-26-2011, 03:20 PM
Ok, let's try this again...

measured again (a little more accurately this time!)..let's make sure I am calculating this correctly:

right side: distance from edge of bell out to the end of the drive flange: 26"..I add five for the rest of the tube in the bell, and 6" for the axle, should make that a 37"

left side: distance from edge of bell to end of drive flange: 24"..so that should make it a 35".

This seems like a wide rear end, as most guys I have seen on here run about 68" overall width...

regardless, the width between frame rails directly above the rear end is 37" (inside to inside)

So, I have a feeling you're gonna tell me I need to change axles and tubes..something pretty much not in the budget at this point. So, if you can give me a sens of what is to be done at this point to make this work, that would be great. Thanks

dfhotlm33c
05-27-2011, 06:09 AM
ok, so chalk this up to idiocy as a result of a long, trying week...

when measuring yesterday, I measured to the end of the drive flange, and attempted to calculate axle lengths from there...which obviously is incorrect, as the axle and drive flange stick out about two inches from the end of the spindle...hence why things didn't seem to add up

regardless, figuring this out correctly and measuring correctly leads to 35-33 axles

again, the width between frame rails, on the inside, just above the rear end, is 37"

so, what do you think?

JAMESGANGRACING
05-27-2011, 11:23 PM
You must have a wide car our 06 smackdown is 33" there.
http://www.mastersbilt.com/setups/setup_widecombo.pdf
try this