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hi anybody got any ideas on how to go about narrowing a c4 vette front suspension? any help would be apprecated. Gary
 

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I'll take a quick crack at it until Chevynut or somebody else comes along with more specifics.

It's really pretty straightforward. You shorten each half shaft the amount you want. Then you shorten the lateral links in a similar manner. Of course if you're putting it in a 55-57 frame you'll need to build the dog bone mounts, differential mount, etc. But those are pretty much the same whether you narrow or not.
 

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The early c4 is narrower if that does you any good.
Jim
 

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hi anybody got any ideas on how to go about narrowing a c4 vette front suspension? any help would be apprecated. Gary
How much do you want to remove on width? What is the suspension going in?
 

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As mentioned, the early 84-87 C4 suspension is about 1" narrower than the late 88-96 ones. The early ones are 61" wide and the late ones are 62" wide, with discs, at the wheel mounting surfaces.

If you narrow the stock C4 k-member or build a custom one, you will have to do something with the C4 rack or you will get bump steer. Also, the mounting brackets will have to be moved or removed to use a different rack. I know Progressive Automotive narrows their custom crossmembers and they use a different OEM rack from a Buick or something else. Nick should know what rack they use.

How narrow do you want it? The narrower you go, the more exhaust clearance problems you'll have. Also, you can compensate for the width by increasing wheel backspacing.
 

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First I apologive for missing the question and talking about the rear.

The stock 55-57 setup is 59-1/2" across the wheel mounting surfaces (brake drums). Most dropped spindle brake setups are 60-1/8" or 60-1/4".

The Progressive clip uses a late 80s/early 90s T-bird rack. I don't know if they narrow it or not, or how it compares to a Corvette rack.
 

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1956 chevy 210 del rey sedan
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c4 corvette front narrowing

I searched for 6 months trying to find someone to build me a narrowed crossmember for late c4 suspension. no luck, so I took a stock crossmember and reverse engineered a jig from it that allowed me to make a crossmember any width I wanted . I built a crossmember with a track width of 58.5 inches wide for my 61 corvette . put it in and it works great . I had a custom corvette rack made at UNISTEER and it was reasonably priced at $400and delivered in about 10 days. took the car in for an alignment and it was very easy to align acording to the front end guy who did it..any questions just send me a PM:party0031::happy0030::)
 

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I searched for 6 months trying to find someone to build me a narrowed crossmember for late c4 suspension. no luck, so I took a stock crossmember and reverse engineered a jig from it that allowed me to make a crossmember any width I wanted . I built a crossmember with a track width of 58.5 inches wide for my 61 corvette . put it in and it works great . I had a custom corvette rack made at UNISTEER and it was reasonably priced at $400and delivered in about 10 days. took the car in for an alignment and it was very easy to align acording to the front end guy who did it..any questions just send me a PM:party0031::happy0030::)
Nice crosmember setup! When you say "track width", do you mean wheel mounting surface width? Track width is to the center of the tires.

Looks like you had Morrison bend the 2x4 tubing for you?

How did you determine what length to make the rack, and what dimensions did Unisteer need? Finally, how did you mount the rack to the crossmember? It's not a very user-friendly setup.
 

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Yes, I got the tube bent by morrison . as far as track width or flange width, call it what you will. stock is 61.5 " on a late c4 and I built mine @58.5" . Unisteer has a form to fill out and I just plugged in the dimensions. basicly narrowing the center section the same 3 inches. as far as mounting the rack I just fabbed up some brackets from 3/16" plate. It did not seem difficult to me. just not as easy as a m*****g II rack . the nice thing about the gm rack is you don't need any pressure regulator crap to make the power steering work . here is a couple of pics of the steering mounts . just not great pics , sorry there all I have
 

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stock is 61.5 " on a late c4
Not to haggle, but I've measured the stock late C4 at 62" WITH DISCS. The early ones are 61" with discs.

It looks like you made the rack sit more vertical at the steering shaft than a C4 k-member would hold it. Your driver's side brackets look vertical in the pics. Is the passenger side bracket machined from a thick plate?

Nice work!! :)
 

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the steering shaft sits at about 45 degree angle to get the best alignment on the steering joints connecting to thhe column. the pass side mount is fabbed fron 1/8" plate steel cut, bend, weld, grind, etc . I used 3/16" plate for the drivers side mount. the mounts are welded to the tubes connecting the fwd mounting of the lower control arms which is connected to the frame and also to the main hoop . . I was thinking about building these to sell but don't know if it is worth the time . John
 

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I searched for 6 months trying to find someone to build me a narrowed crossmember for late c4 suspension. no luck, so I took a stock crossmember and reverse engineered a jig from it that allowed me to make a crossmember any width I wanted . I built a crossmember with a track width of 58.5 inches wide for my 61 corvette . put it in and it works great . I had a custom corvette rack made at UNISTEER and it was reasonably priced at $400and delivered in about 10 days. took the car in for an alignment and it was very easy to align acording to the front end guy who did it..any questions just send me a PM:party0031::happy0030::)
Wouldn't it be possible to use the original Vette k-member and fabricate some brackets on the original trifive frame? If the early model c-4 was used you would only be talking 1/2" on each side.
 

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that could be a viable option but won't be very attractive when you are done :)
 

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Morrison sells a bolt on kit but they do not use a stock k-member. I just bought an 85 Corvette but it isn't here so I really can only go on what I see on the internet so my visual of it is limited. I can say I really like Chevynut's frame and that is what I have decided to go with. I am just throwing idea's out there.
 

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Morrison sells a bolt on kit but they do not use a stock k-member. I just bought an 85 Corvette but it isn't here so I really can only go on what I see on the internet so my visual of it is limited. I can say I really like Chevynut's frame and that is what I have decided to go with. I am just throwing idea's out there.
 
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