1991 Grand Prix SE

[waysideskateco]

Hello, I’m new here but wanted to take the first step toward posting. As you can see in the title I have a 1991 Grand Prix. I just finished getting my DIY exhaust mocked up and ready to weld and I will try to post pictures of it soon as well as other things. I have all new KYB struts and just ordered the rest of the parts I need to build rear coil overs, with the intention of lowering the car a lot. Will start a thread on that soon. Glad to be here. 

[White93z34]

Welcome!! Nice Grand Prix. 

Clean ones are getting harder and harder to come by these days.

[rich_e777]

Nice ride, these old cars really stand out in traffic now and when running good are still pretty easy on the MPGs. 

Ive read and been told by several that the coil over idea on the 1st gens is sort of sketchy due to the rear strut tower area not being reinforced to take that sort of load. A rear tower strut bar might help with that but it`ll have to be a custom made one. There used to be lowering spring options but I dont think those are anywhere out there now. IIRC ST made some for the front and Birchmont had a traverse option.

 

[jiggity76]

 

[55trucker]

4 hours ago, rich_e777 said:

Nice ride, these old cars really stand out in traffic now and when running good are still pretty easy on the MPGs. 

Ive read and been told by several that the coil over idea on the 1st gens is sort of sketchy due to the rear strut tower area not being reinforced to take that sort of load. A rear tower strut bar might help with that but it`ll have to be a custom made one. There used to be lowering spring options but I dont think those are anywhere out there now. IIRC ST made some for the front and Birchmont had a traverse option.

 

It's a misconception that one or all need to *go to* Birchmount Spring here near to me in Toronto to get a replacement steel leaf spring for their car.

Any spring shop can fab up a replacement multi leaf arrangement, the shop just needs to know what spring rate you want, how many leaves you require (the fewer the better ..more than 1 leaf), the total length of the leaves, the ride height you're looking for.

What you see below is what is under my car...the shop I approached arched the 2 leaves to the right height I wanted, seeing as this is a transverse spring each leaf on each side has to be tweeked to ensure that each side of the car's ride height is identical.

 

[rich_e777]

Very cool! I`m going to order one for the `94 when I go to put the ST springs on the front. I had that misconception I guess, I thought those were the only ones. 

[55trucker]

48 minutes ago, rich_e777 said:

Very cool! I`m going to order one for the `94 when I go to put the ST springs on the front. I had that misconception I guess, I thought those were the only ones. 

If you have a set of the ST springs you'll find the drop at the front is approx 1.5 inches using the original rubber hardware, I had a set of those sitting on the shelf for more than 10 years. I couldn't find any Intrax at the time I was looking for drop springs, last year I finally did the cars suspension, the ST are a linear rate spring like the OEM springs. In my case that is better for the car where clearance is concerned seeing as the tires outer corners are directly under the wheelwell lip, spring compression can't allow contact between the tire & the fender lip, the other 3 bodylines don't display this issue as the fenders cover the wheels entirely. They do rider firmer, but to me that's not a negative seeing as (in my mind) the oem ride is far too soft.

The new rear spring is as the chart shows 330lbs. per inch spring rate, this firms up the rear, along with the custom alignment the car corners more exactly, flatter, considerably less understeer.  

The car doesn't *float* anymore.

Edited April 21 by 55trucker