Here we Go ! Tweaking the Ride (Cutting Springs OMG!)

[GreyZone]

Yeah, I know. I think it will just end up being a fantasy...so Im a little OCD...I'll play with the options until I exhaust them or get bored.

[LongBeachCoupe]

I dont mean to be an arse about it... and i assume it wasnt your car... But you have to be out of your mind to heat metal like that in a confined area where there is so much going on... lets say you are dead on accurate at pointing the torch where they need to, and dont burn anything around it (seems like youd need to be a surgeon).... but changing the properties of the spring by weakening its strength thru heat is just not a logical idea in my mind. Maybe someone with more experience on cars can chime in here, but it just seems like they are out of their element doing something like that... (your out of your element donny! shutup! hehe)..... Id consult with someone whose got more experience with chemistry rather than a guy who doesnt see anything wrong with this... i could possibly be 100% wrong though... anyone else hear of this?

[nissantech06]

I dont mean to be an arse about it... and i assume it wasnt your car... But you have to be out of your mind to heat metal like that in a confined area where there is so much going on... lets say you are dead on accurate at pointing the torch where they need to, and dont burn anything around it (seems like youd need to be a surgeon).... but changing the properties of the spring by weakening its strength thru heat is just not a logical idea in my mind. Maybe someone with more experience on cars can chime in here, but it just seems like they are out of their element doing something like that... (your out of your element donny! shutup! hehe)..... Id consult with someone whose got more experience with chemistry rather than a guy who doesnt see anything wrong with this... i could possibly be 100% wrong though... anyone else hear of this?

I worked part-time in the heat treating business so I can agree with everything you just said.

GreyZone, I hope you know I'm not trying to flame you, just warn you of something stupid I did. If you want to do it, go right ahead, but I'm telling you the effort isn't worth it (cutting the springs).

[LongBeachCoupe]

I had a feeling i was right

[GreyZone]

I worked part-time in the heat treating business so I can agree with everything you just said.

GreyZone, I hope you know I'm not trying to flame you, just warn you of something stupid I did. If you want to do it, go right ahead, but I'm telling you the effort isn't worth it (cutting the springs).

Hey man, no flame taken (except of course, by the torcher above, hahaha). ANd I NEVER would have really taken this spring cutting idea seriously except that it was suggested by a nissan employee whose been at nissan for like 20 years, and said he's done this "several times" with no problems. SO, it got me thinking, "ok, hmmm, maybe..." THen, when he told me the springs were only $25.00 I figured, damn, no reason not to try it, can always just undo it. THe front prings are more, so he was $50.00 off the cost of four, but no big deal.

Its just that what Im wanting to do is generally considered impossible. I like the challenge of that. You know, someone says "it can't be done" makes you wanna find a way even more (okay, so maybe Im a bit oppositional/defiant as well).

As far as the TORCH idea, yeah, I camn see it weakening the metal, that parts a no brainer. However, there would be ABSOLUTELY NO WAY to determine if you 've weakened it 20%, 30% or 70%, that's just insane to even try something like that. Waaaaay to unpredicatble IMO.

And I appreciate ALL the feeback, wheter I agree with it or not. This forum was really I think the thing that made my final decision to buy this car. I thought "cool, I wanna be a part of that." S, here I am, coupe in hand, trying to do the impossible.

[LongBeachCoupe]

Exactly... heating something can essentially bring it to the point where they snap if you hit a pebble... you need some pretty complex machinery to make sure the spring is still in spec as far as its strength... I can only imagine what would happen if one of the springs snapped while you were on the highway...

[LegendRacer]

Exactly... heating something can essentially bring it to the point where they snap if you hit a pebble... you need some pretty complex machinery to make sure the spring is still in spec as far as its strength... I can only imagine what would happen if one of the springs snapped while you were on the highway...

not true...when metal is heated, it will be weak until it cools off... as its weakened the spring will lower due to the weight but it will remain like that after it cools and will be STRONG as normal but the spring was not "shortened" just compressed, making it a bumpier ride, but strong

i have seen this done and it works well from what i heard

[LongBeachCoupe]

Well then why would anyone buy new springs to lower their car... its a pain to do the install and somewhat dangerous if you dont have the right tools from my understanding....

Something doesnt add up... It may "work" but that doesnt mean it is reliable...

"i can take a SHlT in a box and mark it guaranteed" - farley

[prelude3174]

not true...when metal is heated, it will be weak until it cools off... as its weakened the spring will lower due to the weight but it will remain like that after it cools and will be STRONG as normal but the spring was not "shortened" just compressed, making it a bumpier ride, but strong

i have seen this done and it works well from what i heard

Steel is a very peculiar metal. I took a few materials classes in college and also interned at a manufacturing plant with an extensive heat treat department. Depending on the temperature, makeup of the metal, time exposed to the heat, and cooling process Steel can be go from extremely brittle to extremely flexible. Without the proper processes of heating and cooling, it will be next to impossible to predict the outcome of just "heating it up". IMO this is not the route to take. Heat it wrong and the thing could snap on the first pot hole you encounter.

See this graph for temperature vs steel crystal structures



I don't expect everyone to understand it, but look closely and you will see the temperatures at which the changes in the metal take place. How are you expecting to get the springs to temperatures that high, all while putting pressure on them???

Anyways, that's just my two cents, good luck on whatever route you choose to take and keep us informed. For me, I'm just going to go with a Pro Kit.

[generic808]

I'm sure heating the metal would compromise the integrity of the metal to some extent. But all this heating talk and no one actually pointed out what really would happen with shorter, cut springs. You have to keep in mind that the springs are progressive rate; meaning, the harder it compresses (going over bumps) the stiffer it becomes.

Let's say it takes 100lbs to compress the srping 1/2 inch, the next 1/2 inch of compression may need 1000lbs of force to compress it, who knows. You're looking for a "softer" ride, but you're actually going to be doing the very opposite. That's why in my first post I said that it'll be a bouncy ride.

[Datalux]

This isn't directed at anyone in particular, just a general sharing of what I know... As others have stated, heating a spring would be a bad idea as it weakens (or at least changes) the integrity of the metal. When you heat an alloy it changes the temper, Do not think that once it cools it will return to its original temper because it won't. You have to go thru very specific processes and procedures to take the material to a specific temper. We anneal and heat treat various alloys at work and believe me it kinda is rocket science.

Companies that manufacture springs go to great lengths to process them in a specific manner to ensure strength, compression rates and prevent sagging. This includes cold forming of the coil, pre compression and shot peening to add strength. Blasting one or three spots on the coil with an acetylene torch is a sure way to negate their attention to detail.

FWIW, I appreciate GreyZone's willingness to experiment (someone has to go first) as long as he doesn't kill himself or one of us while doing so. As for actually cutting the springs, I would use a good band saw with liquid cooling capabilities since you want the spring to see as little heat as possible to retain its strength. Second, I think I would cut half off the bottom and half off of the top. Most springs are progressive, so if you take it all off of one end, I suspect you would be losing the majority of a specific load bearing characteristic. I'm not sure this would actually work as I seem to recall that springs are keyed and each end of the coil needs to sit in a certain spot at which point your stuck cutting exactly one full revolution from either the top or the bottom to keep them aligned.

Good luck and report back soon!!

[GreyZone]

As for actually cutting the springs, I would use a good band saw with liquid cooling capabilities since you want the spring to see as little heat as possible to retain its strength. Second, I think I would cut half off the bottom and half off of the top. Most springs are progressive, so if you take it all off of one end, I suspect you would be losing the majority of a specific load bearing characteristic. I'm not sure this would actually work as I seem to recall that springs are keyed and each end of the coil needs to sit in a certain spot at which point your stuck cutting exactly one full revolution from either the top or the bottom to keep them aligned.

Good luck and report back soon!!

Those are some excellent ideas. I'm not sure if the springs are slotted or notched, that's something I will be doing more investigation into. Technically, some from the top and bottom is a good theory.

I am hopeful that the sedan rear springs will swap into the coupe. That will increase my chances to soften the ride a bit, or at least giving me the same ride, but lower. The dealer ordered both for me, we're going to compare them when they come in.

Another thing helpful to my cause is Im looking to do a relatively short drop, in line with what the Pro Kit would accomplish. About 1" in the rear, 1.5 in the front. Then come the wheels!