Thread: Need knowledge about customizing a chassis for my 46...

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Hello, I've got a 46 Chevrolet stylemaster that I'm in the process of turning into a hot rod. Right now I have a 9" ford rear end on the original leaf springs (just using them to get my measurements right), I already cut the front clip out about 7" from the firewall and now I'm trying to get the proper wheelbase length because I'm installing a 76 cameo sub-frame in it. I was wondering since i have both a new rear end and new front clip will i still need to have the original wheelbase of 116". The problem that I am running into is when doing my measurements I realized that the front wheels will be sitting about 3" forward in the front wheel wells then where the exact middle of the wheel well is.

Now if I were to just get the exact length on each side so the front wheels will sit exactly in the front wheel wells and attached it to my chassis that way, will it throw off my geometric s and such of my car or will it not really matter? Basically is it unadvised for me to turn the original 116" wheelbase into a 113" or 114" wheelbase to line up the wheels in the middle of the wells, even with the new rear and front?

I appreciate the help and apologize if I am confusing in my description of the situation.

The geometry of your front is set by using the '76 Camaro front clip, so the only thing you're going to look at is your rear suspension angles & mount points, right? Set your wheelbase where you want it for best appearance. The 2-3" loss is not going to hurt you, IMO.

So basically as long as i have the rear end exactly perpendicular to the chassis, and have a exact length from the middle of the wheel to the middle of the wheel on each side, get the '76 sub-frame level with where the chassis will be tack welded to it, and have a decent pitch for the drive train to follow to the rear end, then i will be good?

Is the offset the same as the OEM rear end??

When setting up the front clip make sure you get the upper control arms set to the same angle (front to back) as the stock camaro angle. If you don't the caster angle will be off and you will have steering issues. Changing the wheel base length (I.E. different from the Camaro's 108" wheelbase) will alter the ackerman and anti-dive a bit, 5" isn't the end of the world but it does play into the overall handling of the chassis.
Mark

Originally Posted by BenjaminB

So basically as long as i have the rear end exactly perpendicular to the chassis, and have a exact length from the middle of the wheel to the middle of the wheel on each side, get the '76 sub-frame level with where the chassis will be tack welded to it, and have a decent pitch for the drive train to follow to the rear end, then i will be good?

Ben,
I was typing at the same time as Mark, and he brings up very good points on the relative differences of the Camaro to your new wheelbase, and especially watching the control arm angles. I'm by no means an expert on suspension geometry, but if you've considered ride height in the positioning of your front clip (may need to "Z" your frame connection to keep the suspension zero'd at your ride height) then if you have everything square and level you can center your wheel in your wheelwells and be good to go. You mention "...decent pitch for the drive train...". When you set up your rear suspension you will need to set your pinion angle (uptilt) to match the angle of the engine/tranny to eliminate vibrations. Extend a line from the center of your front u-joint through the center of the rear u-joint, and the included angle of the pinion shaft to that line and the transmission output shaft to that line should be equal and opposite. Here's a link to an Inland Empire explanation of driveline geometry http://www.iedls.com/asp/admin/getFi...&TID=28&FN=PDF Maybe some of the more experienced scratch build suspension guys will jump in here, like Dave or Jerry, or ???

First thing has got to be getting the wheels centered in the wheel well, then making sure the track width is something you can live with..... Once you get the wheelbase set and squared then you have to get the A-Arm angle set back to it's stock dimension. If not, caster and anti-dive issues will plague the driveability of the car!

I know the Camaro/Nova front clip idea seems to be so easy and cheap, but it's been my experience that there is a lot more of them done wrong then there is done right, mainly because the people doing the frame graft either don't understand or don't care about how important it is to have the front suspension assembly installed correctly!!!! So, before you weld anything, you're going to need to do some working getting the front and rear suspension set correctly at ride height. To do this, you'll need to actually duplicate the finished weight of the car, best done with the components that you will use positioned in the proper place on the car. Also seen people who "simulate" the done vehicle weight by piling junk inside the car, and not where it will actually be--front to rear weight as well as cross weight must be correct during mock up!!!!!

The grafted on front suspension from the Camaro can be done correctly, but doing it correctly will be neither quick nor easy!!!!!!!