Wheel Hop Problem

2drwagon

Registered User
This post is going to be "way out there" for most of you guys but here goes.....:rolleyes: I have a 64 Chevelle 2dr wagon (cough, cough)that I am going the Pro-Tour route with and would like to put an IRS in it so it will handle more like a new car and not like it's 40 years old. I saw a SC IRS at the Portland Swap Meet this year that a shop was putting in a Firebird. It looked very nice. I liked the fact that it had it's own "sub frame" that would make the whole assembly a bolt in affair providing the recipient car frame was modified to accept it. Here is my question: Do the SC's have alot of wheel hop while smokin' the tires from a dead stop? And, (if so) is there any up-grade parts for this.I don't plan a whole bunch of smoking the tires but you know how it goes sometimes and would like to know what to expect. What about 13" brakes? Who has kits? Or DIY plans? Any help would be big time appreciated. If this works-out I'll be looking for a parts car close to Salem Oregon. Anybody got one?? $$$$ I told you it was "out there"
 
Welcome, sounds like a cool project you have on the go. :)

SC Birds do have wheel-hop issues sometimes, especially on street tires, especially with manual trans cars. Traction seems to be the best answer, if it doesn't spin, it usually won't start to hop, in my experience. What power level do you plan to be at? Auto. or manual trans? Big heavy wheels and tires seem to make the hop worse ... my 255-45-18" on 8.5" wheels won't hook worth a crap at the dragstrip, and are pretty easy to get hoppin'. More solid bushings for the subframe mounting, and the ones in the knuckles, have helped some peoples' cars too.

There are 12" rear brake kits available, and I have some brackets for doing an easy 11.65" (Cobra Mustang) swap using the factory SC calipers. 13", you're on your own as far as I know.


cheers
Ed N.
 
ED, Thanks for the re-sponce. I'll be in the 300hp range with a manual trans. The wheels are 17" Welds with 235-45-17's.Which are about 25" tall. (I have room to go a bit bigger to "fill" the wheel well down the road) Solid or stiffer subframe and knuckle bushings seems to be an easy fix/upgrade. Does that effect ride quality and road noise. I'm getting sick of compromise, I want the best of all worlds. I think I may have the 13" brakes figured out.Major big-time thanks for your help.
 
More solid subframe bushings would very likely increase noise and harshness, but to what degree I'm not sure. I do know that when Roush Industries prepped some SC Birds for the Bondurant Race school in the early 90s, that was one of the changes they made.

Knuckle bushings probably wouldn't impact ride harshness too much IMO.

What have you found for 13" rotors? I've been knocking around some ideas for larger rear brakes (I currently have the Cobra 11.65" rears), but haven't found a suitable 13" rotor with the correct thickness to go with the SC calipers. There is always the aftermarket caliper with fabricated bracket route, with the separate parking brake calipers, but I certainly don't feel like spending $1000+ on rear brakes just to get some more rotor diameter.


cheers
Ed N.
 
My possible 13" rotor solution won't you any. If I run a SC IRS I'll need to redrill the hubs anyway (to match the bolt pattern of the front hubs) which will allow me to run Corvette rotors. Ed, thanks for taking the time to help me out.Are you the only one on this site?? Are we alone?? I do fabrication and machine work for a living, if you need help with any car projects and don't mind working over the phone/web let me know if I can help.I own the shop so the boss won't get mad if I use the equipment on a weekend or at night. Max
 
Max, there are a ton of regular posters on here. I'm one of the guys who usually tries to answer the brake and suspension questions.

Thanks for the offer concerning the fabrication. I do have a local friend who is able to do a fair amount for me, he is the one making up the caliper relocation brackets I sell for putting the Cobra 11.65" rear rotors on the Birds and Cougars. I actually have a pair of C4 Corvette 13" front rotors drilled for Ford stud pattern sitting in the basement, that I've been eyeing up. They were leftovers from my Fox Mustang track car with Baer brakes (I ended up going down to 12.5" on the front of that).

I'm not sure if the SC hubs will have enough meat on them to go from 5 on 4-1/4" pattern up to the GM 5 on 4-3/4" ... you may need to get a pair of the 99 - 04 Mustang Cobra IRS hubs to give you some more room to work with. They are a direct swap for the Bird hubs as far as bearing size goes.

I'm only going to worry about larger rears if I come up with something bigger for the front as well. My car usually sees a few open-track days on Hooiser race tires every year, so the brakes do get a bit of a workout. The Mustang 13" front / 11.65" rear stuff has been working pretty well so far, but by next year I'd like to do something more with it.

Out of curiosity, do you post on www.pro-touring.com ? I've been on there a bit, looking for info and ideas for my old Cougar.


cheers
Ed N.
 
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Ed, I'm sure there are alot of good/smart guys on this site, just trying to stir-up a little interaction.I've posted a few IRS questions on different sites in the last two weeks with almost no response,you are the exception. I'm starting to get bummed-out, all of my questions that I have ever posted on my regular Chevelle site seem to go this way. I should start asking the kind of questions that get response " Hey everybody, what oil filter are you runnin" Those seem to get all the press.
Yes, I've been lurking around pro-touring.com Trying to find-out all I can about this IRS stuff. Lots of Camaro builds going on, I'm trying to gleen as much knowledge as I can to what would cross over to my wagon, but not much talk in the line of Independent.
Thanks for the tip on the OD of the SC hubs,if the SC IRS is the way I evenually go the I'll check into the Cobra hubs.
The braking set-up you have going sounds very nice. I would be happy with what you have on my wagon, no problem.
Need to go, yap at ya later, Max
 
ok being the only one with a sc 5 spd that dont get wheelhop.

what is needed is if you use the stock rubbermounts you need to take the inner shaft mounts and cut 1/4 inch from them so rubber can compresss more it will lock up the whole suspension tight and viola no wheelhop at all.

I at firts used a big washer to compress ir but later modified the stops inside the mount its all about getting the mounts as compressed as possible

i posted pictures some where on the none tech ill find em and post later today:D
 
hey manny,

I would also benefit greatly from some pics; as my car is looking at completion by the end of the summer.
Thanks, Scott
 
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