Okay....here is a letter I composed and will send out to a couple of race shops in my area (one is Chris Alston).
---------------------------
Convert from standard Corvette Independent Rear Suspension to solid axle rear suspension.

I would like to convert my 1972 Corvette to a solid axle setup, but NOT back halve the car.
This conversion would be strictly for increasing the durability and reliability of the rear end, but NOT to increase tire size. I would like to have a rear end installed that would give me the maximum width of tire possible WITHOUT cutting or removing any of the undercarriage other than the IRS components. But I want this without cutting or otherwise changing the floor or wheel wells. As far as I know this conversion HAS been done using a 12-bolt GM rear end and retaining the Corvette transverse spring. However, if the only way this conversion can be done is with a 4-link/ladder bar setup, that would be acceptable.
Again...no back-halving/tubbing of the rear is permissible. I would prefer if the conversion would use a Ford 9-inch rear end, but if that isn't possible, the GM 12-bolt rear end would be acceptable. I would like to have the components used in this conversion be supplied by Mark Williams whenever possible. Please let me know if you can do this conversion.

 

That's the way to do it...can go back to the IRS if the need arises...

 

I got my hands on a Chris Alston catalog. Looking close, the ladder bar rear end conversion doesn't have that "high hump" in the frame that the 4-link does. I wonder if that would be an option??? Almost looks like it could mate right up to the Vette frame!!!

Dep

 

any replies yet?

 

I don't think that you'd get around removing the rear crossmember. A solid axle will need more travel than the space for the driveshaft in the rear crossmember. Making it removable would be a possible option...

 

No replies yet. Just sent the letter out.

Dep

 

Not a problem. I just don't want any tubbing or hacking up of the interior of the car. Look at the ladder bar conversion. Travel appears to be MUCH less than the regular high-hump 4-link.

http://www.cachassisworks.com


Dep

 

I also womder about the storage compartment and battery compartments... They might have to go too...

 

I mentioned it before, but to reiterate:
My friend has run a 12-bolt in his '66 427 roadster for over 30 years without incident. It is a Camaro unit.
He used the entire unit- along with the springs and perches- that was once in his brother's A/MP '57 L-88 Corvette.
There is no tubbing, and the vehicle has performed flawlessly at the track and on the street.

If you want to spend a gazilion $$$$, then be my guest- but this is an economical and sturdy setup.

 

Olivier: Yep...was out in the garage looking at that. They will both have to go. No big deal. As long as nothing INSIDE the interior has to be chopped up. Looks like must removing them and filling the hole would be needed.
Battery can easily be relocated to under the hood. No problemo.

MassVette: Don't get me wrong, I sure don't WANT to spend a bundle on a solid rear axle installation. But I have to have someone who is able to DO this installation. I also need someone who has the engineering ability to come up with a solution. If your friend is willing to come out to my place, I'd be more than happy to pay him to do the conversion
But I suspect it will have to be a place like Chassisworks who will do it.

Dep

 

While Alston's Chassisworks is probably more-than-capable of doing what you request, don't over-look what a competent, intelligent, and 'thinking-man' can do in his 2-car garage, Mike.....
several of the guys at my local track have cars built in such places, pass NHRA/IHRA Tech Certification with no troubles, hook-hard-and-go-straight, etc.

If you had a nearby-track, no-doubt you'd have access to more "do-it-yourself" style racers.....

Are you near Joiliet, Illinois:
I know that Ken Hoger Race Cars has built cars for a local IHRA Modified Eliminator Record Holder, and several of my buddies have his cars, including this blown '68 Mustang:
http://www.pittsburghracewaypark.com...m=107&pid=7442

http://www.pittsburghracewaypark.com...m=107&pid=7443

 

Glen: Unfortunately, Joliet is a pretty good cruise away from me. I am closer to the Wisconsin border and Great Lakes Dragway in Union Grove, WS.
I have no doubt that a guy could build what I am looking for in his garage with the right tools. I can write out what I would like (as above), but the engineering part of it is beyond me. So I am forced to seek out a shop like Chassisworks. I still want to go with a solid axle using as much of the Corvette equipment as possible. I just need to find out if it's practical and safe.

Dep

 

I heard from Chris Alston's shop today in response to the letter I wrote...

From: "JIM WRIGHT" <JWRIGHT*@cachassisworks.com>
To: "Michael L Bonomo" <mbonomo*@juno.com>
Date: Thu, 5 May 2005 13:42:17 -0700
Subject: RE: Convert from standard Corvette Independent Rear Suspension to solid axle rear suspension.


Hi,

The corvette is hard to do because the rear axle centerline is so close
to the back of the seat. With a lot of modification on your part during
installation you can use the 4-link and crossmember package it includes
the 4-link with 4130 ends, track locator, 2x3 front crossmember, upper
shock mount, VariShock Quickset 1 coilover shocks, springs and lower
adjustable shock mounts. This package sells for $1152.00 plus shipping.

Jim Wright
Sales Manager
Chris Alston's Chassisworks, Inc.
-------------------------------------

Not too bad....although I don't think this setup is a DIY that I would want to tackle. I am going to write back and ask them how much labor they charge for this conversion.

Dep

 

you've got over $1100 in suspension, less narrowed (proper-width), modified, and 'built' housing, center-section, and axles, less labor.....

I'm guesstimating $5,000, complete, which doesn't include wheels and slicks, possibly another grand.....

..... which STILL ain't-bad for a C3 that'll repeatedly hook-hard, go-straight, and never break a sweat.

Please keep us posted on further developements.

 

Sent this tonight and got a reply already:

From: Michael L Bonomo [mailto:mbonomo*@juno.com]
Sent: Thursday, May 05, 2005 3:08 PM
To: JIM WRIGHT
Subject: Attn Jim Wright

Hi Jim,
Thanks for the answer to my question. I'm glad it's a doable
conversion. I have one more question. I have limited facilities and
equipment for this type of conversion. What would your shop charge for a conversion of this type? Would a FAB 9 housing be an option with this conversion?

Thanks again,
Mike Bonomo

Reply:

From: "JIM WRIGHT" <JWRIGHT*@cachassisworks.com>
To: "Michael L Bonomo" <mbonomo@juno.com>
Date: Thu, 5 May 2005 16:51:38 -0700
Subject: RE: Attn Jim Wright

Hi,

We do not do the installations. Where are you located?

Jim Wright
Sales Manager
Chris Alston's Chassisworks, Inc.
-----------------------------

I replied that I am 10 miles North of Chicago and close to his location.
I suspect he will recommend a shop close to me that can do the work.
That would be great!!!

Dep

 

10 MILES OUTSIDE OF CHICAGO?


That's Chi-Town HUSTLER territory, get Farkonas and Coil to do it!!!!!


In all seriousness, they'll (Alston's) find you somebody close-by who'll be more-than-capable of this rear-end swap.

 

Actually, it's Mr. Norm's Grand Spaulding Dodge and Nickey Chevrolet territory

I think you're right that they will find a good reliable shop nearby. I'll keep everyone posted.

Dep

 

I too like the 1320,..much more than "turning or braking on a dime", which bores me. I've seen several solid rears in Vettes,..even with leaf springs that almost looked factory.

Here's my question though. This is the 21st century with stronger alloys (and lighter). Why hasn't a supplier built u-joints and half-shafts that are strong enough for the job. Half shafts and their u-joints are sent half the torque of the driveshaft,..yet the weak link is the IRS.

Can somebody make a reliable U-joint? You'd be rich in a hurry.

Dark Blue

 

..... it really wouldn't matter if those pieces were made of 'un-obtainium':
even semi-serious drag-racers, being what they are, will prefer the simplicity and durability of a solid-axle over ANY type of I.R.S. with it's various multpile 'joints', which offers very-little in the way of 'tuning' the suspension for differing starting-line conditions (as-opposed to a 4-link, with it's various instant-center positions)

 

Dark Blue, the 1480 series spicers are bullet proof. Noone ever has broken a 1480 half shaft u-joint..