If you're not going to do it right, and have no conscience, just get some of those cheesy spring clamps like JC Whitney used to sell and clamp it down until you're happy. That way when the whole mess fails the riders' survivors will sue the clamp manufacturer because he obviously has deeper pockets than you......I know, I know...."JC WHO ?"
The OP says, in his profile, that his occupation is "cl***ic car restoration". He MUST know what he's doing.
Oh, and you can flip 6-a-year in CA. One more, and you are looking at an investigation. One of my neighbors just got nailed, a few months ago.
some of the later chevelle springs are shorter than the earlier ones but i dont know about 69s. dont heat the springs! its a chevelle anyway most people that buy them dont want them dropped in the dirt anyway
71-72 are shorter, or you can get some 5413 Moogs for 40 bucks on the bay. About 2.7 inches shorter, similar rate.
Absolutely heat them, it is the best method. But do it properly [ Not with a F***en torch ] Firstly you need to know how much the spring needs to be "shortened" [eg on a falcon 1/2" at the spring lowers the car 1" ] Make up a simple spring compressor out of a piece of threaded rod to pull the spring in. you only need to shorten the static height because the vehicle will have the same weight on it so the load distances will be the same. Heat an oven to 400c [ 750f ] and leave the spring in there for about 30 minutes and let it cool slowly if this is too difficult ,take the coils to a spring maker [ you've already pull them out ,which is the difficult bit ] Note:When I've had springs professionally reset , the original paint on them was still intact so DON'T HEAT THEM TOO MUCH You need to weigh up the costs of the electricity [ 1/2 hour x 4 ] and the tool against paying a pro
Haha! Yeah, then my advice is to go to posting #2 Heat them until it sits on blocks of wood [it'll be dead level mind you ] Then take the blocks away, and see if the new magic suspension doesn't take up any load and sit down even further Or take the novel approach of heating them and trying to "time it", so it cools just shy of settling on the blocks [ a CO2 extinguisher could help cool it if it drops too fast ] All stupidity aside, The purpose of my last post was to teach [those with open minds] how to do it properly. The secret is...... TIME & PATIENCE Heat them slowly all the way through at LOW [ish] temps and cool them slowly
What this poster wanted, was for someone to agree with him so his conscience wouldn't hurt. He didn't want advice, he wanted complicity. Shame on him. Selling parts and is not what this site is about; even if it has cl***ifieds for that purpose. I can't speak for Ryan but my perception is that for him 'art' comes before part, and 'raise hell' comes before sell. Someone needs to clue the newbie (can't believe I'm saying that). This is more like a museum and most of us work in the ba*****t as conservators. The gallery you're looking for, sir, is down the street, and yes you can walk there. Or, better yet why don't just run along?
So this method really works safely? I've never seen reference to it before but the principle seems sound. Posted using the Full Custom H.A.M.B. App!
Old POS ovens do, modern electronic ovens usually stop at 250c 400c isn't that hot in metallurgy terms, the secret is lots of time to let the heat soak evenly all the way through. that's why spring "blacksmiths" charge so much [ yet people don't want to pay them for their time /costs ] You'd probably save 25% DIY which I think isn't worth it. There is also the Old Timer blacksmith method of "Cold Bulldozing" the springs with a br*** hammer. But this is even more time consuming I wonder how many Old Hambers know how to do this?? The old guy that tried to teach me this died 30 years ago
=============== Fred Puhn's HP book "how to make your car handle" described the technique. And mentioned that it could take a bit of trial and errror. I was thinking the temp was 400 F, but I can;'t check that right now because the book must be buried in a box someplace. "heat" can have different meanings, similar to what President Clinton points out @ 1:10 here - http://www.youtube.com/watch?v=xHlt1W83JFU
There was a neat thread here on the Hamb on how to Reverse-eye a leaf spring using a hydraulic press. What they basically did was use a press to exceed the modulus of elasticity of the spring steel until it yields [ Yield is when permanent deformation occurs and is reached when the stress/strain curve suddenly goes non-linear ] With a coil spring you cannot do this because of the design of the spring [ if you press it ,it would simply coil bind well short of the point of yield ] So to re-set a coil it needs to be heat-treated correctly. Basically it means an increase in thermal energy, will decrease the mechanical energy required to yield the steel. The MAXIMUM temperature recommended is 650°C (1200°F) for all [except tempered high–strength steels.] Higher temperatures in excess of approximately 700°C (1300°F) will change the molecular composition, altering material properties after cooling. There is only a 50°C window between the maximum and changing the composition , so it is not recommended to go that high
================== I forgot to mention Fred Puhn said something like " it is a disaster to try and heat spring with a torch - you will probably ruin the spring." Fred Puhn was a 60s sports car racer of some success. I think he was an engineer for Boeing or someone out on the west coast. He even produced a series of sports racing cars of his own design. Santee, Quasar, maybe some others. http://www.utsandiego.com/news/2011/Jun/22/cobra-beating-santee-sports-car-featured-fair/ http://sports.racer.net/ch***is/quasar/page1.htm http://www.tamsoldracecarsite.net/SanteeSportsCar.html Fred Puhn also wrote "The Brake Handbook" along with ***istance from Mac Tilton. In "Engineer to Win" the late great Carrol Smith said he had seen the m****cript and it had everything any of us are ever goint to want to know about braking systems. I will buy it when it comes out and suggest you do also."
Even if it does wind tighter at the top and bottom you can still cut em. The smaller diameter sits in one part of the 'cup', then there's enough provision for the next larger diameter to the outside of the cup. Armed with that you should be able to look at it, figure out where to cut 1/2 a coil from the top and bottom, job done and no damage to the strength of the spring. As an added potential benefit, since coil springs are rated in "inch lbs", or pounds per inch compressed, it should handle better and provide a ride that's just a bit more firm. The spring will be into it's higher rating "sooner" by virtue of compression. It's a fine line to achieve that, and also easy to take too much out. I diced off exactly 1 coil from an F body front spring, but the spring was rated for a 2nd gen Trans Am with A/C. The iron head BBC that was in it dumped the front just right, but the stored energy in the remaining coils combined with old school 90/10s made it stand up real nice, and stay there under load.
There is a huge difference between heating a coil spring with a torch to lower it and doing what is know as a heat set like Kerry suggested. Spring shops do the latter all the time, hack low riders do the first method. kerry - it's funny you mention the hammer method. Years ago we had a friend move here from NZ and live with us for a while. He ended up being a mechanic on an Indy car team before burning out and moving back to NZ. He had originally come over as a Rally Car crew member. Anyway, he bought a 1972 Capri and wanted to lower it. So one day I come home and he is out front and has the rear leaf spring on the bench and it beating them with a lead hammer. I am shocked. He says wait til you see me do the coil springs from the struts. It took him HOURS but when he was done it sat a 1/2" lower and rode perfect.
Hmmmm.... I have a cousin who is a potter and has a fancy electronic controlled kiln.I'll Have to investigate the numbers on resetting springs some more. Posted using the Full Custom H.A.M.B. App!
No it doesn't. Even if some people are victims of their own stupidity. There are posts here which are for the benefits of others to pick up some knowledge. That was the reason I joined the Hamb. To learn [and to teach] And to make friends [ and some foes ] The old saying goes "never try and teach a pig to sing, you waste your time and annoy the pig"
Seems I saw on another thread that the best way to cut them is to submerge the spring in water and actually do the cutting part by sticking the end of the cut off wheel into the water with it.
HaHa! the good old Kiwi DIYer. Unfortunately these talented people are dying over here as well. The secret I believe is a soft hammer [br*** is what I saw] , probably similar to shrinking sheet metal with a soft hammer. I decided to Google "cold bulldozing" [and variants] this morning, It obviously is a forgotten science. All I got was 2 forums http://www.camaros.net/forums/showthread.php?t=27899 http://www.digitalcorvettes.com/forums/showthread.php?t=86710 and this PDF on the automotive technique http://www.ncnr.nist.gov/AnnualReport/FY1999/residual.pdf Even in the magical world of "internetland" it is relatively unheard of. Hopefully some old timers can chime in. From memory though, I wouldn't want to do this at home. In my neighbourhood they would be more receptive to me practicing "Bagpipes" on a Sunday morning , than bulldozing springs
The Jalopy Journal
