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Roadrage David
09-13-2009, 10:49 PM
Guys i have been blasting 3300 miles sins the finish of my road straat racer sins Oct last year. at first the car was very stable in the suspention departmend.
But lately i feel that my Hodkish 2 inch drop coils are getting softer!!.
when doing some serius speeds on the highway i drive over fade bumps and my exsaust hits the tarmac.
i also feel the car is droping to mutch when driving over theses fade bumps in the road, the stace is the same nothing wrong with that.
i use the SBC coils because my pontiac engine hase alu heads alu manifold ecetera. haveing said that the normal weight of a pontiac engine is right inbetween a sbc and a bbc. there was some stuff aded under de hood but the nose and hood are from fibreglass.
so im starting to think i might need the bbc coils, any particulair brand and tension i should consider???. the rear hase 2 inch drop DSE leafs de firm not harse type....

John Wright
09-14-2009, 02:59 AM
I don't think that it is very common for coil springs to lose their rate. What bushings do you have in the control arms? Are they still the factory rubber or are they something else?

79T/Aman
09-14-2009, 03:54 AM
coils will not change rate but they will sag, the distance between the coils get smaller making the spring shorter, the bushings will also get looser regardless of the type of bushing, as far as springs I would look at 650-700#

Roadrage David
09-14-2009, 10:31 PM
the car is equipt with all the goodies mini tubt everyting.. so do you sell the 700 rate for First gen.......

neki67
09-15-2009, 12:17 AM
Shocks still fine?

John Wright
09-15-2009, 04:12 AM
the bushings will also get looser regardless of the type of bushingYup, you loose the extra little bit of effective spring rate when the bushings loosen up. The factory rubber is especially bad for adding a bit of spring rate, moreso than the others.

Roadrage David
09-18-2009, 01:10 AM
Guys Koni schoks and the car was alredy on its feet for2 years with al the stuf installed. it now hase 3300 miles on it and at first it was very stif but now its losening up, and bounses more douwards. i gues ading a thing ore 2 here and there under the hood made the coils to light for this aplication.
so who hase the best 2 inch drop BBS coils for a first gen racer

GetMore
09-18-2009, 03:33 AM
If the nose of the car is stall at the right height then the springs are fine. I would blame the shocks.
That is assuming that everything was fine before all the driving.

Since you say that it bounces downwards more, but had been stiffer, I think it's the shocks.

Springs support the weight, while shocks control the movement. It sounds like you are lacking that control.

79T/Aman
09-18-2009, 04:49 AM
agree, check the shocks, it sounds like the shocks are getting soft, the sprigs still have to hold the same total weight, but it also sounds as if you may have added weight to the front, is this correct? if so then more spring rate may also be needed

a73formula
09-18-2009, 12:02 PM
a pontiac motor with alluminium heads and intake weighs the same as a sbc. That with the fiberglass parts you should be fine with the springs. Sounds more like a shock problem to me. And I'm talking about an all iron small block which is what I believe the springs are based on.

Roadrage David
09-18-2009, 11:12 PM
Formula 73 i knew all that but thanks anyway to point it out, i did instal a havey halve inch thick billed alu valve cuvers.
This winter a variable lifter rocker system will FINALLY be instaled this ads another 25/30 lbs under de hood. have 3 ecstra oil radiator up front dubble remote oil filters with long hoses all sorts of stuf that thuse ad a little weight.
shocks are brand new koni,s haveing driven 3300 miles to date might have loosen the parts a bit up in a way they should behave afther the running in time????.
In anny case i need stronger 2 inch drop coils. for sure. i was thinking going for the same Hoskish 2 inch drop coils but for BBC. anny other sirgestions!!!!!...

Hotchkis
09-22-2009, 08:45 AM
Some pretty good advice in here already. In 15 years the only springs we've ever had come back losing tensile strength were when the owner tried to powdercoat them or got them hot with a torch. More likely you have a defective set of shocks, OR you've been adding extra weight to the car which is lower ride height and causing it to bottom out more easily. We just released new lower front 2" coils for your 1st gen that will do the trick, and they're a bit firmer for autocross competition.

Turbo Rob
09-22-2009, 02:42 PM
Guys Koni schoks and the car was alredy on its feet for2 years with al the stuf installed. it now hase 3300 miles on it and at first it was very stif but now its losening up, and bounses more douwards. i gues ading a thing ore 2 here and there under the hood made the coils to light for this aplication.
so who hase the best 2 inch drop BBS coils for a first gen racer

David - just slow down (betje langsam) for the "drempels" and you should be okay!