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Lowering Question

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Old Sep 19, 2000 | 06:42 PM
  #1  
RPO_B4C's Avatar
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Lowering Question

I have a 1985 Pontaic firebird. The past Couple of months ive been wanting to lower the vehical and ive checked out how much lowering springs would cost me. I ddont find lowering my bird a critical mod but i want to do it and im not going to spend the money for aftermarket lowering springs. Ive talked to people and they say that i can just cut the springs. Ive seen the after product and u cant see the difference. Does anyone have and input/opinion about this? Do you think it would be a good idea/bad idea? After cutting the springs what gains/losses would i get? and finally does any one know of how i would exactly go about doing this and the tools i would need? Thanks in advance.

[This message has been edited by RPO_B4C (edited September 19, 2000).]
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Old Sep 19, 2000 | 10:29 PM
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Well, if you're bound & determined to cut the springs, I'll at least explain it. Once you remove the spring, look at it. You'll be cutting off a portion of the coil at the top of the spring. Examine the end of the spring because it usually sits against a tab in the spring pocket. After you cut the spring, you may have to do some shapeing to the end to get it to fit correctly. The best way to cut the spring is with an abrasive cut-off wheel mounted on a air powered die grinder. Use saftey glasses or better yet a face shield. If you need to contour the end of the newly cut spring, use an abrasive disk on a grinder. Yes, you can use a torch to cut the spring, but you'll still need to clean up the end with a disk grinder.
How much to cut off? I suggest starting with 1/2 a coil. That should drop the car 1 to 1-1/2 inches (my estimate). On any coil spring, as the number of coils are reduced, the spring rate goes up (spring becomes stiffer). Rule of thumb for 1/2 coil remove is about a 10-15% increase in spring rate.
Also, keep in mind your suspension travel (jounce) is reduced by the same amount you lower the car. Do not remove or cutdown your rubber syspension bumper stops to regain suspension travel. They are there to protect your suspension components. If you lower beyond 1-1/2", you'll also have to start paying attention to such things as shock absorber travel & link adjustments on your anti-sway bars.
Regards, FJK
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Old Sep 19, 2000 | 11:07 PM
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RPO_B4C's Avatar
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Thanks alot for replying. Just a couple of questions for you. So nothing more that 1-1/2 inches right? that is a definate safe point to stop at? Also do you think that would be a very noticible drop as in appearance?
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Old Sep 20, 2000 | 12:20 AM
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cy Z28's Avatar
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From: Ft. Worth, Texas
Car: 1989 Formula 350 WS6
Engine: L98
Transmission: 700-R4 2600 stall
You are FAR BETTER to buy springs. This is a major modification as far as the overall appeal/handling of the car. I got mine for just 120 bucks from Grenatelli Motorsports. You might still be able to get them @ this price.

GMS: 818 996-2753
Tell them you saw about the clearance sale and wonder if they have any thirdgen springs left. They'll do everything you want them to do. Cut springs are not the way to go, I've learned my lesson the hard way.

------------------

Cody "cyZ28" Young
'84 black on black Z28

355, 5-speed (on the way out. What goes back in, ooohh baby!!)
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Old Sep 20, 2000 | 10:24 AM
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ERIC'86IROC's Avatar
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cy Z28 - How much did those Granatelli springs lower your car? How well do they handle? What shocks and struts are you using with them? Do you think they will be better than my stock IROC springs? I am wondering if they will be worth it since I don't have AC and I'm using a fiberglass hood. I don't want to buy them if they only lower the front of my car about 1/2 or 3/4".

------------------
350 Vortec, forged flat-tops, CompCams XE268, Edlebrock RPM, Holley 3310, TH350 w/Holeshot 2400, 3.23 posi, Heddman shorties, HEI
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Old Sep 20, 2000 | 10:33 AM
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cutting the springs is a bad idea for sure. just spend the $150 $200 it costs and pick up some eibach lowering springs(or other manufacturer) eibach's lower the car about 1 1/2" and you'll notice a big difference in the appearance and the handling of the car. also the springs are significantly stiffer than stock so your car will handle alot better.
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Old Sep 20, 2000 | 04:28 PM
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you can buy some intrax springs out of summit for 189 to lower it 2 inchess and if you look in a jc whitney catalog there are spring compressers that lower your car up t o3 inches for 30 dollars to do all four springs or you can just take a torch and heat your springs up and they ll lower then when there where you want them you can just throw cold water on the springs

------------------
92 camaro 25th anniversarry polo green with 2 gold stripes

89 camaro
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Old Sep 21, 2000 | 08:43 AM
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ERIC'86IROC's Avatar
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Yeah, or you can just pour wet cement onto the floor until it is as low as you need. Hopefully you will still have room to sit.

I really hope the torch + cold water suggestion is also joke.

------------------
350 Vortec, forged flat-tops, CompCams XE268, Edlebrock RPM, Holley 3310, TH350 w/Holeshot 2400, 3.23 posi, Heddman shorties, HEI
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Old Sep 22, 2000 | 11:44 PM
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cy Z28's Avatar
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From: Ft. Worth, Texas
Car: 1989 Formula 350 WS6
Engine: L98
Transmission: 700-R4 2600 stall
I honestly don't know how much they lowered the car as my car is sitting in the air with no susp. or powertrain right now.

------------------

Cody "cyZ28" Young
'84 black on black Z28

355, 5-speed (on the way out. What goes back in, ooohh baby!!)
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Old Sep 24, 2000 | 01:19 AM
  #10  
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Eric, I also have removed my A/C and have a 'glass hood. I lowered my car with Eibach springs, and although they did lower it 1.5 inches in front, as advertised, it doesn't sit 1.5 inches lower than a stock car, it sits 1.5 inches lower than it did, which was high because of the weight loss. I have since cut my stock springs and am going to throw them in until I achieve the right stance and then measure and find out the difference between that and the Eibach, and then cut a small amount off of them, hopefully no more than 1/4-1/2 coil. Hope this helps.

Randy
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Old Sep 25, 2000 | 12:04 PM
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ERIC'86IROC's Avatar
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Sure does help. Thanks for the reply MeanYellowZ.

------------------
350 Vortec, forged flat-tops, CompCams XE268, Edlebrock RPM, Holley 3310, TH350 w/Holeshot 2400, 3.23 posi, Heddman shorties, HEI
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Old Sep 27, 2000 | 10:44 AM
  #12  
Bruce89TA's Avatar
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From: Dallas, Texas
Car: 89 Firebird T/A
Engine: 305 TPI
Transmission: 700R4
Just to clarify, springs won't get stiffer when they're cut, spring rate remains constant no matter what length the spring is (of course not including variable rate springs). The spring will have less travel and the spring will act differently because of the length of the spring (in this case being shorter). With a shorter spring, the spring will not be able to take as much weight before reaching total compression so if anything the spring will act as if it's weaker than before it was cut. That's how I understand it.. I'm sure someone'll correct me if I'm wrong.

------------------
Bruce Chang
ICQ #2992488
89 Firebird Trans Am
305 TPI, Jet Airfoil, Hypertech Thermomaster Chip, Edelbrock TES, Hotchkis LCA's and Panhard Rod, B&M Shift Kit, March Power Pullies, Suspension Techniques Lowering Springs, Flowmaster Muffler, Accel Super Coil, Energy Suspension motor mounts, tranny mount and torque arm bushing
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Old Sep 27, 2000 | 02:25 PM
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Yes, here is the correction...
A coil spring is nothing more than a torsion bar wound in the shape of a coil. When the length of the bar is decreased (ie cutting a coil) the rate increases. Two springs with the same coil diameter, wire diameter and number of coils will have the same rate regardless of the height because the "torsion bar" is the same length. Often times when a spring is cut, the small increase in stiffness doesnt make up for the amount the vehicle was lowered.
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Old Sep 27, 2000 | 07:52 PM
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From: Illinois
Merf 23 is entirely correct. An important point to remember, from a practical standpoint, is that the slight amount of spring rate increase can not compensate for the loss of suspension travel you get by cutting coils to lower the car. For every inch you lower the car, that is an inch of lost suspension travel. That is one of the reasons why springs that are designed to lower the car are also designed with a rate increase (beyond what you get from cutting coils). This rate increase is necessary, in part, to minimze the chance of "bottoming out". Obviously, the higher spring rate is primarily viewed to increase the roll stiffness.
Regards, FJK

[This message has been edited by FJK (edited September 27, 2000).]
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