Cutting springs & Idle issue

[slvrGT179]

I want to lower my car about 1.5" front and back. I don't have the funds right now to buy new struts, shocks, and springs to lower my car so I was thinking about cutting my springs. Is it possible to do this with stock suspension? I know I'll need to get it realigned but besides that, will my car be okay till christmas when I get new struts, shocks, and springs?

And also, my idle has been around 600rpms. I feel like that is rather low compared to when I first got the car. Is this normal?

[Frankenstang]

Cutting springs be bad. Everytime you hit a bump your car will do this.
Is there a certain reason you need your car lowered before Christmas?

I would suggest just leaving it is until you can do it right, because if you dont like the bouncy ride, than you are screwed. Also its gonna be like doing twice the work, and you will probably have to get an alignment after you do it the right way also. So if you do cut em, save yourself a little cash and get a Lifetime Alignment.

As for the idle, Im not sure about on Mustangs, but I know a majority of cars idle around 1000 in park and 750-800 in Drive.

[2k4mk1]

http://www.lonestarstangs.com/forum/...ngs-60331.html

Above sill solve your lowering issue WO cutting your springs which is a really DUMB idea.

As for the idle if that is with AC on it is not too low

[slvrGT179]

http://www.lonestarstangs.com/forum/...ngs-60331.html

Above sill solve your lowering issue WO cutting your springs which is a really DUMB idea.

As for the idle if that is with AC on it is not too low

Ah-ha...okay then that's what it is. It only does that when I've had the AC on. And Ill check those out

[Torquer]

i'd sell you those springs for $70 shipped to ur door

[thatdavidkid]

if your springs are a linear rate, cutting them is not bad.. unfortunately i think yours are not linear.. the mach springs however, are. i'id buy those and cut half a coil off.... furinox has cut springs in his mach, i had cut springs in mine before the coil overs.

[slvrGT179]

But having stock suspension and putting some cut springs, wouldn't that mess up my struts and shocks? And would i not be better off just buying some new lowering springs instead of cutting those springs to lower it an inch?

[slvrGT179]

i'd sell you those springs for $70 shipped to ur door

I'd only be able to do around $45 since I'm getting my car worked on and don't have much cash laying around

[thatdavidkid]

buying the right parts is always better.... that mach i talked about has stock mach 1 tokicos up front with caster camber plates so that helps the struts, the rear is an irs with billsteins, also cut springs but cobra springs... rides ok for only aftermarket part being c/c plates.

[Drew03tx]

i cut my stock springs in the rear and ive never had a problem with it, doesnt bounce like a lowrider either.......

[86sleeper]

i have put a lot of money into my car and i use cut stock springs. Granted i am not that low compared to most, but it gives me the performance i was after.

[slvrGT179]

Does anybody have any how to's on how to cut spring? And will I need cc plates?

[Torquer]

get a saw and cut it....lol

Go 1/2 a coil at a time...cus you cant put it back....

CC plates are good to keep alignment....Like David said Linear rate springs are better when cut because of the spring load and responsiveness....the cut factory spring jolt the suspension...Linear rates wont be as rigid.

Do yourself a huge favor ...hold on real tight when driving 70 mph and hitting bumps in the road with cut springs....the car will be far less predictable

[JCP281]

if your springs are a linear rate, cutting them is not bad.. unfortunately i think yours are not linear.. the mach springs however, are. i'id buy those and cut half a coil off.... furinox has cut springs in his mach, i had cut springs in mine before the coil overs.

+1. There is nothing wrong with cutting a linear rate spring(within reason), its progressive rate springs that can not be cut.

[thatdavidkid]

+1. There is nothing wrong with cutting a linear rate spring(within reason), its progressive rate springs that can not be cut.

i agree... are the gt springs of those years linear? that's what i was getting at, i thought they were progressive...
edit: didnt see the +1...

[JCP281]

They are linear. the bullitt/mach 1 springs are 600lb linear rate and GTs are 450lb linear, V6's are 400lb linear.

[slvrGT179]

And what does the linear rate mean? Would I be able to cut my springs by 1/2 a coil?

[JCP281]

Linear rate means that the spring will always have the same spring constant, k, at any given distance , x. F(force)=-k(spring constante)*x(displacement of spring)

For a linear spring, no matter the compression of the spring or length of the spring, the force that the spring puts out will always be a constant number. Thats where the 600, 400, 450lb numbers come from.

[thatdavidkid]

rather than a progressive spring which gets stiffer as it is compressed.... yes, you would be able to cut your springs half a coil if you chose.

[slvrGT179]

Now that I understand thanks for the help guys. Really appreciate it

[JCP281]

Anytime man. Its always nice to learn a little bit of the physics side about how your components work. Just knowing that basic formula(hookes law) and how it works alone will give you the go ahead for cutting your linear rate springs. I wouldnt cut off more than a 1/2 coil though for what its worth. after that you start to get really low.

[slvrGT179]

Anytime man. Its always nice to learn a little bit of the physics side about how your components work. Just knowing that basic formula(hookes law) and how it works alone will give you the go ahead for cutting your linear rate springs. I wouldnt cut off more than a 1/2 coil though for what its worth. after that you start to get really low.

Very true. Last question... What is the best way to do this? I need to take off the wheels, unbolt everything needed to take off the spring, cut it, then put it back together? Could I do this in one day by myself and Jack stand? I need a spring compressor from auto zone too right?

[JCP281]

the easiest way to do it is for the front:

unbolt the caliper from the rotor, take off the 22mm nut from the center of the c/c plates in the motor bay, unscrew your swaybar end link, jack up from the bottom of the rotor and slowly let the a-arm down. The spring will eventually decompress.

Just take a cuttoff wheel to the spring.

The back is pretty self explanatory, an 8.8 SRA has only 2 connection points per side lol....well 3 if you count the shocks.

[Torquer]

Linear rate means that the spring will always have the same spring constant, k, at any given distance , x. F(force)=-k(spring constante)*x(displacement of spring)

For a linear spring, no matter the compression of the spring or length of the spring, the force that the spring puts out will always be a constant number. Thats where the 600, 400, 450lb numbers come from.

Your information forgot one key detail....the rate remains the same until the coil binds / collapses (bottoms out) . When you shorten the spring you lose rebound causing coil bind to occur more rapidly - rendenring the spring rate ineffective and creating all kinds havoc.

If lowering a car was as simple as cutting a spring and keeping the car safe at all speeds and driving conditions - then the entire spring aftermarekt world wouldnt exist.

Drive your car carefully if you cut the springs - Your responsibility goes beyond yourself...if you lose control - you may hurt someone other than you.

[slvrGT179]

Your information forgot one key detail....the rate remains the same until the coil binds / collapses (bottoms out) . When you shorten the spring you lose rebound causing coil bind to occur more rapidly - rendenring the spring rate ineffective and creating all kinds havoc.

If lowering a car was as simple as cutting a spring and keeping the car safe at all speeds and driving conditions - then the entire spring aftermarekt world wouldnt exist.

Drive your car carefully if you cut the springs - Your responsibility goes beyond yourself...if you lose control - you may hurt someone other than you.

And on that note, I think I'm just going to save up for new suspension parts I don't want to spend time and have troubles.

[thatdavidkid]

And on that note, I think I'm just going to save up for new suspension parts I don't want to spend time and have troubles.

good choice. you can't go wrong with something like a pro kit, if you are just gonna drive around and enjoy the car... if you plan on racing, there are tons of options, but a pro kit will give you a good stance without being TOO low... good shocks and struts are key, and then a good set of camber plates and an alignment will finnish it up nicely.

[Frankenstang]

Wait.... did someone mention A/C? What is A/C? Is that something only rich people have?

Congrats on waiting to do it right. I dont care what anyone says, the right way is the only way when it comes to lowering. Especially if your wife/kid(s) are going to be riding in it. Cutting springs is what ricers and Swangers do. Lone Star Stangs.... Swanger Edition!

[JCP281]

Your information forgot one key detail....the rate remains the same until the coil binds / collapses (bottoms out) . When you shorten the spring you lose rebound causing coil bind to occur more rapidly - rendenring the spring rate ineffective and creating all kinds havoc.

If lowering a car was as simple as cutting a spring and keeping the car safe at all speeds and driving conditions - then the entire spring aftermarekt world wouldnt exist.

Drive your car carefully if you cut the springs - Your responsibility goes beyond yourself...if you lose control - you may hurt someone other than you.

Cutting a half coil off like this guy wants will in NO way mess with the structural integrity of the spring. I would not cut more than a coil off, but what he want(ed) to do it perfectly acceptable. People have been doing that for YEARS in the hot rod groups, which might I add created the aftermarket parts industry.

This notion you suggested that your "hurt someone other than you" is completely false, and quite frankly the most ridiculous thing I have ever heard. The spring will not preform different by cutting off up to a coil(which will lower it about 2"), please explain to me how someone would get hurt. Your "spring bind" statement is not even applicable in this situation. For what its worth, all aftermarket linear rate springs are basically a cut spring with a stiffer wire for increased rate. They are shorter than the stock springs, which the "spring bind" theory suggests would cause havok!

I also find your statement about keeping your car safe at all speeds to be rather ridiculous. Stock suspension should not be used at ANY speeds above highway speeds anyways. Cutting the stock springs will not make your car any more unsafe than it already is. If you want to haul ass, you need a lot more upgraded than just your springs...which have nothing to do with the predictability of your cars rear end.

EDIT: And dont get me wrong im not starting shit with you, I know where your coming from. If you cut off an absurd amount, there are going to be a few issues, but keeping it reasonable will cause zero issues with form and functionality. You can prove this mathematically to yourself if you ever have the time by using the f=KX formula in conjunction with your before/after cut spring numbers.

The thing that irritates me the most about stuff like this is most people who oppose this do so because to them its ghetto, which is understandable. But scientifically have no valid reasoning as to why its not a valid way of doing something.

[2k4mk1]

Well having seen cut springs that look like noodles when removed I wouldnt do it. Some on here have seen the pics of the ones I mean

[Steve]

Do you have a CEL on? If so what codes?

[Torquer]

Cutting a half coil off like this guy wants will in NO way mess with the structural integrity of the spring. I would not cut more than a coil off, but what he want(ed) to do it perfectly acceptable. People have been doing that for YEARS in the hot rod groups, which might I add created the aftermarket parts industry.

This notion you suggested that your "hurt someone other than you" is completely false, and quite frankly the most ridiculous thing I have ever heard. The spring will not preform different by cutting off up to a coil(which will lower it about 2"), please explain to me how someone would get hurt. Your "spring bind" statement is not even applicable in this situation. For what its worth, all aftermarket linear rate springs are basically a cut spring with a stiffer wire for increased rate. They are shorter than the stock springs, which the "spring bind" theory suggests would cause havok!

I also find your statement about keeping your car safe at all speeds to be rather ridiculous. Stock suspension should not be used at ANY speeds above highway speeds anyways. Cutting the stock springs will not make your car any more unsafe than it already is. If you want to haul ass, you need a lot more upgraded than just your springs...which have nothing to do with the predictability of your cars rear end.

EDIT: And dont get me wrong im not starting shit with you, I know where your coming from. If you cut off an absurd amount, there are going to be a few issues, but keeping it reasonable will cause zero issues with form and functionality. You can prove this mathematically to yourself if you ever have the time by using the f=KX formula in conjunction with your before/after cut spring numbers.

The thing that irritates me the most about stuff like this is most people who oppose this do so because to them its ghetto, which is understandable. But scientifically have no valid reasoning as to why its not a valid way of doing something.

WOW -- talk about a rant

So good luck to anyone that cuts a spring....

I do have to ask why the engineers with the LIABILTIY RISK (in this case Ford) risk didnt make the springs shorter. you can apply all formulas and logic you like... you are not carrying the liability.

[JCP281]

It wasnt a rant, its just some intelligent conversation.

Ford engineers havnt designed a spring since the 80's.. they pretty much have carried over the same springs for the mustangs. Aftermarket springs are shorter than stock springs, I dont understand your point?

And don, the ones that look all bent out of shape where not done correctly. If you use a cutoff wheel there is zero distortion of the spring. Some people who do it decide to take a torch to em and ruin the springs physical shape. That is when problems occur.

[Steve]

the point is he already said he was gonna wait.

Does your idle stay steady at 600, or does it drop and kick back up?

[slvrGT179]

the point is he already said he was gonna wait.

Does your idle stay steady at 600, or does it drop and kick back up?

It drops and kicks back up between 600-900

[JCP281]

the point is he already said he was gonna wait.

Does your idle stay steady at 600, or does it drop and kick back up?

I realize this, but he made his decision based off what I would consider, not very reliable information, per the given circumstances of the question.

Your idle is likely being caused from a dead IAC controller or a vacuum leak. Or your TB set screw is a little bit off.

[slvrGT179]

IAC controller? And how could I check for a vacuum leak? Doesn't that cost lots of money? And where is the TB set screw?

...I don't know very much...

[JCP281]

You IAC, Idle air controller, is what meters the air into your motor while your stopped. when they become old the valve gets gunked up and starts to malfunction. For a vacuum leak just take a bottle of soapy water and spray it over your hoses and look for bubbling.

Heres a guide on how to set your TB screw

Cliff Knight, the guy who wrote that article and who created that site is a pretty accomplished engineer. He has a mechanical engineering degree from MIT and writes a lot of software. Coincidentally, he also doesnt seem to have issues with cut linear rate springs.

[slvrGT179]

Alright cool Ill check all of that. Thanks. I bet it's IAC

[86sleeper]

check the IAC and don't be afraid to cut your springs. If you don't like it, then go and buy new ones at no loss. Use a cut off wheel and some water to cool the cutting area down every 20 seconds or so.
Once again, I use stock cut springs and my car is fine. Pretty fast and fine.

[slvrGT179]

check the IAC and don't be afraid to cut your springs. If you don't like it, then go and buy new ones at no loss. Use a cut off wheel and some water to cool the cutting area down every 20 seconds or so.
Once again, I use stock cut springs and my car is fine. Pretty fast and fine.

I'm just worried about taking the suspension apart and not being able to put it back together correctly

And does anybody know, if I put 315/35s on my deep dish 17" bullitts that i just ordered for my 2000 GT, will they fit fine or will they rub?