suspension question
 

Hi, I have an 84 gs with a gsl rear end, re-speed coils and tokicko blues. I just bought it and have come to realize is extremely twitchy mid corner. It is pretty scary to drive through a corner. Not even that fast either. It also has 15" diamond wheels with a 4" backspacing (0 offset) with crappy 195 tires. Any ideas why this could be so screwed up?

I would check the suspension components to see if anything is bent or broken

tire pressure too high? depending on the size of the tire, etc etc, good starting point is about 26 cold, like what it says in the door jamb.

Crappy tires will make a difference.

As the prior poster recommended, I would check your tire pressure and tread wear and see if you can bump them up a bit. If you're all professional and everything, you could get a tire pyrometer, run some hot laps and then take temp readings across the tread to determine if you're getting good contact patch around the corners. If you're low-rent like me, I'd just ditch the crappy tires for some quality rubber, check for other suspension 'upgrade' opportunities, and go from there.

The car can only corner as good as the quality of your tires. Like most things in life, you get what you pay for.

Have you had the car aligned since you installed the suspension parts?

I just bought the car as is. So no alignment yet. I will check that next. The tire pressure could be it as well. I will check tomorrow. I have been under the car quite a bit and haven't seen any broken suspension parts. I do know the bushings are toast everywhere. Thanks for the ideas I will check all the easy ones tomorrow.

I had sr rated 14" on mine and thought my snap oversteer had a lot to do with the rear suspension. Installed "vr" rated 17's and it's a fuck'in gocart again

You'll need to go through all of the steering linkages. Tie rod ends, Idler arm (replace with Moog unit), ball joints, control arm bushings, pitman arm. Any slop in any of those parts needs to be addressed, and any of them can contribute to erratic handling.

I would suggest that you address any issues found there before you get an alignement done, otherwise you will have to do it again once you do replace those parts.

Good luck. :)



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Thanks I will get it up in the air and start going through the steering components

Here's a pretty discussion on all that you will need to know: https://www.rx7club.com//showthread.php?t=785410

good luck :)

What set-up (shocks, springs) do you have in the front suspension, and please let us know what your spring rates are front and rear? If you only upgraded the rear, and the front is pretty much stock, this could be a big contributor to the issue. Also do you have the rear swaybar on, and have you upgraded the swaybar on the front.

Just not clear if you only upgraded the rear or all-around. Thanks!

-Bern

I bought the car as is. It has respeed coils all around. The front say 250 on the coil. havent checked the rears. Tokicko blues all around. Sway bar up front is stock. No bar in the rear.

My first thought was the spring rates were too high for street use but didn't remember that until just now. What is a good street rate for the respeed coils?

Thanks, Jordan

I run 275/150 spring rates and have no issues. Even made a trip to North Carolina, which is like 800 miles each way for me. No problems, and this is still my daily driver. I think your spring rates are just fine.

Do you have the adjustable perches in the rear? Does the car sit level? (side to side, front/rear)? Do you have the camber plates too?

But really, all of this speculation is worthless until the steering components are confirmed to be in good shape, and you have had it aligned. If I had to make a guess, I'd say you've probably got a bit too much toe out.

I'll second Kentetsu on the spring rates. I have the same spring rates, but haven't installed the Re-Speed sway bar. my car still is much better than stock. I also recommend checking all the steering linkage. I would also add to check the wheel bearings.

i'll second the toe out..

you might also want to get some better tires on the rear. when i upgraded from 195 to 215 i had a major performance increase

thanks for the information... check the rear spring rates, if they are more then 200, this is a bit much for a street car... also since you mentioned the car is really twitchy at most "not fast" speeds, the tires are probably not the issue. I don't know what NOT FAST really is for you... but I'll assume a bit more than normal road speeds. If you could gives an idea here?

As others suggested, check the tire pressure, easy stuff first, than all of the suspension links/bushings for looseness or damage. If the bushing are toast everywhere, as you say, this maybe an issue magnified by the newer suspension pieces. Do you hear any rattling or thunks?

Get all this is right and tight, THEN get yourself a real nice wheel alignment, and if needed, some new rubber. The tires are the best thing one can do, but if all the basics are not right, it doesn't matter.


As a last check, make sure the GSL diff is in proper working condition.


-Bern

I can tell you your situation has nothing to do with spring rates and most certainly is a toe setting.

Even a bit of toe in can turn into toe out with worn out tie rods. Replace those first then get an alignment.

If you PM me the name of the person you purchased the car from I can tell you the rear spring rate, as well as anything else that was purchased for it.

-billy

Well, my "not fast" speeds varied since the road was pretty windy, but there was a late model Chevy full size pickup that was sticking with me pretty good the entire way. I don't have any loud thunks or rattling but my car is soo loud anyway its hard to tell sometimes. I am continuing to check the small stuff.

How should I check my rear end? I had the rear up in the air not too long ago and both wheels would spin the same direction. As far as I understand this means the LSD is still working, correct?

Yes, both should turn the same direction with a lsd diff. Get Billy the name of the previous owner and he'll give you the specs on the parts purchased for the car (just in case you missed his reply above). :)

no comments about no rear sway bar? i seem to remember a post asking about using one or not but don't remember what the outcome was.

Common opinion seems to be that removal of the rear swaybar can decrease "snap oversteer".

alright. just wanted to rule that out as the culprit to the problem but wasn't sure if anyone noticed he had mentioned it didn't have one.

maybe you might want to loosen all the rear suspension, it might have been tightened before it was lowered, then tighten everything (with the car on stands or with the rear end lifted up)

Rearwheelsonly: in case u didn't understand the last post, he means retighten everything with the weight of the vehicle on the suspension.

I see. I will try that as soon as I can