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View Full Version : A-body rear, should I go lower?



ponchopwr70
12-31-2009, 08:30 AM
Ok heres my delemia. I want to lower the rear of my car one inch. Right now I have eibachs 1.3" lower spring in the rear. I have my pinion angle set as good as I can and lowering it would prob make it a little bit worse. Second after talking to Marc at SC&C its going to make the roll center worse too. But when I look at my car I wish it was a inch lower in the back. Now I think if I bought a spring with a stiffer rate which I do kind of need (my car understeers autocrossing) I will have less travel and ride height might not be that different under driving conditions from where I'm at now. So I'm faced with leave as is and have no problems or lower and maybe run into more problems and loose some handling. Here's some pics I have a 2.25" rake right now.
https://static1.pt-content.com/images/pt/2009/12/lemansoct09032-1.jpg?t=1262276164
https://static1.pt-content.com/images/pt/2009/12/lemansoct09003-1.jpg?t=1262276958
https://static1.pt-content.com/images/pt/2009/12/lemansoct09015-1.jpg?t=1262276998

Roadbuster
12-31-2009, 09:12 AM
Frank,
Looks wise I say lower it!

Performance wise lower it and see what you think. The cost is not much. New linear rate 11 inch single pigtail springs cost about $50 each. Get 2 progressive jounce bumpers from Mark ($20) and remove the pinion snubber from the frame (free). Leave the pinion angle alone. Drive it and see what you think. Swapping the springs back is a easy task and could be done for auto crossing days. You are out about $120 or so.

It is important to remove the pinion snubber. I found that it was hitting that before the jounce bumpers and made the car do weird things in the corners. As low as you are now take it out especially if you have raised the pinion.

You need good shocks in the rear and you will have limited bump travel (hence the need for the progressive jounce bumpers). You will also need to secure the springs to the axle.

Mine is a little lower than yours with 175 rate 11 inch Hyperco springs. Love the look and the roll center is not a problem for normal driving. Push it with some dips and road slope changes and it feels like the rear end is wandering a bit. Makes me not push it as hard as I probably could.

A Watts is on order :ssst: to fix the roll center (I have been talking to Mark too!) in my car.

Jon

ponchopwr70
12-31-2009, 10:17 AM
Yea I was thinking off getting the springs you have because your car has a perfect stance. Im getting some varishocks this winter too. Another thing is my lower control arms are not parallel to the ground, they are closer to the ground at the rear end than the chassis which is a good thing. How are yours with those springs?

Taman
12-31-2009, 02:09 PM
I think the stance is good. Try a little taller tire. If those are 40 series go with a 45. An inch taller tire will fill the wheel wells and give you the look you require.

novaderrik
12-31-2009, 03:58 PM
fill the gas tank and put a full size spare tire in the trunk. that should lower it another inch. if not, add a small toolbox.

b-man
12-31-2009, 04:38 PM
Lower the rear, it definitely sits too high.

Install a set of adjustable upper control arms to get the pinion angle where it belongs.

Roadbuster
12-31-2009, 06:14 PM
Yea I was thinking off getting the springs you have because your car has a perfect stance. Im getting some varishocks this winter too. Another thing is my lower control arms are not parallel to the ground, they are closer to the ground at the rear end than the chassis which is a good thing. How are yours with those springs?

Frank,

My rear lower control arms are at a slight angle with the axle side slightly closer to the ground than the frame side.

How tall are your rear tires? Mine are 26.4 inches tall and they do tuck just a little.

Jon

ponchopwr70
01-01-2010, 09:28 AM
My tires are 25.7 they are 315/35-17 nitto drag radials, I'm hoping to get the new nt01's in that size. There are no options for a taller tire for a 17" rim unless I go with a suv type tire. I would have to move up to an 18" rim in the rear to go taller. I do have the edelbrock adj arms and have no problem adj. pinion angle its just the angles get worse when the rear end moves up in the car. My wheel wells measure 26.5 from the ground in the back and 24.25 in the front.

Tony_SS
01-01-2010, 10:06 AM
I think the tire height is ok.. I'd go lower in the rear and adj pinion angle as needed after that.

ponchopwr70
01-04-2010, 06:26 AM
Yea I think I'm going to be buying some springs this week I need it lower.

Marcus SC&C
01-04-2010, 09:26 AM
I`m with Taman, larger dia. rear wheels and taller tires. Put a 27" tall tire on an 18" wheel in that wheelwell and it`s look awesome. The taller tire will give you a longer fore/aft contact patch for more straight line traction too. I know springs are cheaper but these cars just don`t have that much bump travel when you lower them. Bottom them out mid turn and vehicle dynamics change very suddenly! You`d may never run into it on a mild street cruiser but I know you drive the car hard enough to butt heads with it. Mark SC&C

buddyleerc512001
01-04-2010, 01:19 PM
sweet ride. i say lower. i also feel you need to tuck the exhaust up high in the rear.
where are you hiding out in rhode island?
i live in warwick

ponchopwr70
01-04-2010, 01:43 PM
Oh thanks Marc I just might have to listen to you now my credit card is going to thank you! Now Im going to have to find rims and tires. Im in Foster buddy.

ponchopwr70
01-04-2010, 03:49 PM
Actually unless I can find cheap used 18x10 torq thrust I'm not in a position to change wheels right now. Marc whats a good distance to have between the centerline of the axel and the highest point of the chassis kick up?

ryfrat
01-05-2010, 04:50 PM
I have some 18" front and back you could try to see if you like it.