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I recently had a visit to the top of the tire wall, pretty easy as these things go Any how I have strings, springs, copper hooks, and a 1/2" block in old camera film cases to run from the rear wheels to the front. Anybody know what the 'general rule' is for the toe setting on an ITA Rx7?
Any and all feed back is appreciated.
I run 1/8” toe in. if you have any toe out it is a handful under braking. I am told you need a little more toe in if you have the stock rubber bushings on the front tension rods.
AS far as toe settings, a number of questions come to mind.
are you running the spacers on your shock towers that ISC sells?
What bushings do you have?
How fast do you want to go and what kind of car control do you have?
I run 3/16" toe out. It is a handfull under braking and the car will dart around on you but the turn in is tremendous.
My suggestion is to start at 0 to 1/16" out and try it.
Just my opinion.
Mike C
Scott,
0 to 16th in
Roland
I agree with Mike Cox. 1/16 out in the front. Toe in makes the car darty, toe out helps you keep it free in the apex and get some speed in the turn exit. An eighth out is not uncommon.
I run the rear neutral, but have heard of some who like it 1/32 - 1/16 in. If you put any toe out in the rear it will make it very darty.
Mike Cox has a wealth of experience so you can expect good results from his recommendations.
Just curious, how do you set the rear toe?
I'm anxiously awaiting the answer to this one... I figure it will apply to my Volvo, as well. :DQuote:
Just curious, how do you set the rear toe? [/b]
By bending the rear axle..... Really.Quote:
I'm anxiously awaiting the answer to this one... I figure it will apply to my Volvo, as well. :D
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I'm a guessin' he's got one adem 2nd gens withat new fangled indy pendent rear spension.Quote:
I'm anxiously awaiting the answer to this one... I figure it will apply to my Volvo, as well. :D
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Well it is obvious the answer is set it where it works for you......I just moved mine from nuetral to about 1/32 toe out. I'd describe it as squirmy under braking, but the turn in is much improved. Of course I also lowered the ride height 1/2" and cranked up the front shock damping at the same time so I am not sure what was the main factor. I had previously run nuetral to slight (1/16 or so) toe in.
BTW I am running a 1st gen RX-7 with poly bushings and for all practical purposes a spec-7 suspension.
Might be a good idea to bump steer the car and see what it is doing on the brakes and during turn in. The toe in or out is just a compensation for changes in the front toe.
Thanks for all the responses.
Mike Cox : As fast as H E double hockey sticks! And hopefully enough to keep me off of that darn rubber wall!
I do have turn in spacers in the front and Blue ( Suspension Techniques?) front stabalizer bushings.
I'm still adjusting the rear panhard bar to keep the rear axle under the car since fabbing my own after the tire wall incident.
It seems like the rear axle is wider than the front? And running strings from the front to the rear it seams like I got about 1/16 Toe out. It wasn't too bad last time out, but I had other issues to deal with as well.
I also wasn't as fast as I was before...cojonies not as big as they used to be, too much weight lifting the night before (12 oz at a time), different wheather conditions, car not up to snuff.. Hmm
Always in search of that unanswerable question. 'Why the heck can't I go that fast!'
Obviously. Now... please show me page and paragraph in the ITCS that allows this modification.Quote:
By bending the rear axle..... Really. [/b]
Scott, toe out to suite.
Jake, we been through the rear toe on a 1st gen in the past.
Mike Cox, it's great to see your messages again. :023:
I'm sorry David, refresh my memory, how did you adjust your rear toe?Quote:
Jake, we been through the rear toe on a 1st gen in the past.
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Obviously. Now... please show me page and paragraph in the ITCS that allows this modification.
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Gary, it's right in the ITCS book, right next to that passing rule. if you time it just right and hit the car trying to pass you and can do it just hard enough you can get 1 degree negative camber in your rear axle housing. Of course we have all tried it and we usually get 4 degrees camber, a flat tire and a meeting with some old men.
David, Thank you .Nice to be back, Took a year off to recharge my batteries.
Thanks too Mike, Since I'm getting up in years, it's time to start passing down what I have learned and that I will gladly do....................well most of my tricks at least....................never know when I'll have to reach back and show you youngsters a thing or two.
I'm not suggesting a modification, I'm telling you how to repair a damaged axle housing. There is no specification for the toe or camber of the rear axle. However, it would be reasonable to assume that the Mazda engineers didn't intend for there to be toe out or positive camber in the rear since this destabilizes the rear. If you have either of these conditions you probably hit something and damaged the axle. Repairing the axle housing so that the tires point straight ahead and are upright is completely reasonable.Quote:
Obviously. Now... please show me page and paragraph in the ITCS that allows this modification.
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Dialing in 2 degrees of negative camber would probably fall outside anyone's "reasonableness" test. But due to the lack of a spec, you still wouldn't be able to stop someone from doing it. However, replacing your rear bearings after every race weekend would probably get old.
Protest this and I absolutely guarantee that you will lose your protest fee. This isn't just an opinion, the argument was thoroughly tested in CalClub a few years ago in the Pro7 group. Their rules are governed by the ITA rules. The SCCA tech steward denied the protest due to the lack of a specification.
Joe has a good point (nice name btw) - "lack of specification". I doubt the protest would hold. As far as the mechanics of doing it, it can be down with a chain, torch and lots of muscle. Toe and Camber. But you will cook the bearings, every race.
Steve also has a good point. Toe is only as good as the setting made without weight transfer.
I had to bend the rear axle on my car two years. It was in a big crash and after we got it put back together it just didn't turn like it was supposed to. Measured the toe on the rear axle and it was 3/8" out. Cut the housing, bent it dead straight, welded it back up and I've been running it ever since. As far as putting camber in the rear, the gain your going to get is not even close to the pain of pressing on new bearing all the time.
Scott,
Are yopu using stock rubber tc rod bushings or poly?
Roland
Been doing the negative camber rear end trick for the last 30 or so years with not one bearing problem to date. If you bend the housing at or near the bearing, it will eat bearings all day long. You MUST bend the houseing as close to the center as you can. This way the bearings will never know the difference. There's plenty of play in the spider gears to allow this legal (???) mod. 2deg max please. Works for me.
For those that are running toe out to help with the turn in, are you also running turn in spacers with a revised ackerman or is this in place of doing that. I have never tried running toe out but I am assuming what makes the turn in better is the inside wheel being turned more.
Trying to learn, thanks.
Roland, I have G-Force Engineering turn in spacers, Poly bushing on the Tension Rods, not sure about the control arm bushings.
Scott, with poly tc rod bushings then it would be 0 to 1/16 out. More than that and you'll start scrubbing speed that we don't have down the straights!
Roland
***I'm sorry David, refresh my memory, how did you adjust your rear toe?***
Jake:
I know NONE of you folks in the North East do anything that is not spelled out in the ITAC.
You could ask your GOOD your parts pedler friend in Ohio.
As a matter one poster told all within this thread the LONG method, one told you the QUICK method & one told all that he has done it forever.
Push your selective recall memory button & you will recall the my method is between the LONG method & the QUICK method.
I could tell you again but then you would tell me AGAIN it's illegal. :014:
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For those that are running toe out to help with the turn in, are you also running turn in spacers with a revised ackerman or is this in place of doing that.
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I'm curious to know the answer to this as well. Is it one or the other? I have a set of poly's coming in for the LCA and tension rods. My caster was pretty messed up after the CMP-kink run off and the front just feels sloppy now.
***I'm curious to know the answer to this as well. Is it one or the other?***
Strut spacers & toe out.................
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I run 1/8" toe in. if you have any toe out it is a handful under braking. I am told you need a little more toe in if you have the stock rubber bushings on the front tension rods. [/b]
Is that total toe or per side?
My suggestion is to start at 0 to 1/16" out.