86 Coupe Suspension
Thread Starter
Race Director
Joined: Jun 2005
Posts: 17,640
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
86 Coupe Suspension
This is somewhat difficult to explain, but I need some help. I just about completed a restoration though I did not do any suspension work on a 86 Coupe. When I finally got the car on the road and get on the acclerator hard the rear end "squats" and the car pushes to the right just a quick jerk in the steering wheel to keep the car going straight, this also happens right when I let off the gas as well. It does not continue to pull during the accleration period only when you drop the hammer initially and let off. Upon inspection I notice that the gap / distance between the top of the rear tire and the upper most point of the rear fender is different between the right & left of the car. So with this said I need any availaible assistance, maybe how to adjust the ride height, some suspension part that has gone bad. As a side note the rear wheel bearings are shot but not to the point that I think would cause this. Just a little chatter when you rock the wheel back and forth. This car is a 4+3 transmission. Thanks for your help
Pro
Joined: Sep 2003
Posts: 670
Likes: 1
From: charlotte nc
I would start by replacing the wheel bearings. You would be surprized as to how much a bad bearing can impact the way the car handles. Secondly , I would check out the C beam to be sure the bolts are tight and it is not shifting under hard launch. and lastly, Checkout all the suspension parts and bushings . If nothing else is loose , or worn, I would have it aligned by someone who knows vettes, not just any alignment shop.
Thread Starter
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Joined: Jun 2005
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Is the 'C' Beam the fiberglass beam that runs right to left behind the differential? I have all four bearings on order and I am going to have an alignment person look at it hopefully tomorrow, he says he has done Vettes and comes recommended by a friend who builds high performance cars. I appreciate your help Thanks.
Thread Starter
Race Director
Joined: Jun 2005
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
This is a manual transmission, I do not believe the beam is on the car, there is "spring" bar kind off like a leaf spring that bolts to the overdrive unit then runs to the rear differential. Maybe I overlooked it, I will look tonight. Thanks
Drifting
Joined: Sep 2004
Posts: 1,638
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You better have it!
It's essentially a 3 sided aluminum beam that runs from the transmission to the D44 rear end. The drive shaft sits inside the beam.
Originally Posted by rspreng86
This is a manual transmission, I do not believe the beam is on the car, there is "spring" bar kind off like a leaf spring that bolts to the overdrive unit then runs to the rear differential. Maybe I overlooked it, I will look tonight. Thanks
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
It looks like a C, though technically looking towards the rear of the car its a flipped backwards, but its aluminum and it bolts onto the end of the 4+3 and runs to the D44 rear differential.
You better have it!
ZFDoc's c-beam plates are supposed to help remedy the problem of the kicking right under hard acceleration, also keeping the bolts real tight will help too.
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Thread Starter
Race Director
Joined: Jun 2005
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
I just was not paying attention, I raised the car and found the beam I checked the bolts on the rear end and transmission and they were tight. Will there always be a bit of kick with hard launch shift changes? The car also kicks a little when cruising at ~50mph and stepping on it even in fourth w/ overdrive engaged. I am still baffeled that the opening above the rear tires varies from side to side with the car sitting on flat pavement. Is there a way to adjust this or is it normal? Thanks everyone for your help thus far.
Bob
Bob
