front springs squashed

[TOPTON]

Finally got round to ordering and fitting new springs for the front coilovers. I ordered 350lb 7" 2.25 id springs. When I dropped the car onto its wheels, it squashed right down to the bump stops. So obviously 350 lb is not enough. Tried to corner weight the car to get a rough idea but bathroom scales are no good as they only go up to 266lb.

With the car weighing in at around 2300lb, dividing that by 4 wheels makes 575 lb each, the front is obviously heavier than the back, I am guessing 70-30 split, then the front should be around the 800lb per wheel. That seems too much so may go for 500lb springs.

Any suggestions???

Anyway, NOT happy now, springs aren't super expensive but at £55 a pair they not cheap either.

Twine over!!!!!!

[blaineuk]

I have 2 springs you can have, no idea on poundage, they are from the Steve Heath coil over set up, let me know if they would be any use.

[Lesliehedley]

I had this problem when I tried to fit Steve Heath's coilovers to my 400SE. We tried various spring rates. Steve supplied 375lb/inch springs and they were definately too soft for my 400SE. I tried 400 and 450 springs. For other reasons I went back to the standard setup. The 450 springs are probably a good starting point. I think you'll find you need at least 450 springs, but each car is probably a different weight so there's a bit of trial and error involved.

[JR]

Lesliehedley said:

I went back to the standard setup.

Interesting deviation from the other rates posted. The 350i cars ran 120lbs/in as standard with the 400SEs slightly stiffer. The OP's problem is related to spring length, not rate.

[TOPTON]

blaineuk said:

I have 2 springs you can have, no idea on poundage, they are from the Steve Heath coil over set up, let me know if they would be any use.

Thanks very much for your kind offer. Not knowing spring rate is the problem. Being in tight mode at the moment, I don't want to pay postage on something that might not be right. Thanks anyway TT

[B@man]

Sorry for the Thread Hi-Jack.
Anyone know what the standard poundage is for 400SE rears ?
Mine are too soft and it's bottoming out.

[TOPTON]

JR said:

Lesliehedley said:

I went back to the standard setup.

Interesting deviation from the other rates posted. The 350i cars ran 120lbs/in as standard with the 400SEs slightly stiffer. The OP's problem is related to spring length, not rate.

I beg to differ sir, my problem is spring rate. I have fitted 11" adjustables with 3" downtravel, so 11x8's. I know I need 7" springs as with this the shocker is fully open and with only 3" of suspension, there isn't much room for sag. Any longer and the spring would need compressed to fit, therefore being spring bound.

I have spoke to RT Racing this morning, top bloke. Although he couldn't supply me with the correct size springs, he was still happy to talk and help.
He suggested as said by Lesliehedley that 450lb is a good place to start. 500lb 'may' be too hard he said. So I have ordered some 7"x2.25 x500lb

[BoltonTVR]

I went through the heartache of converting to coilovers last year and went through a couple of different sets of springs before I got the right ones. The springs I was supplied with compressed completely when first installed. I was a gnats chuff away from binning the whole setup but in the end, when I fitted 450lb springs, it came together. It seems to be holding up OK, but I do have a set of unmodified lower wishbones if I do need to revert back. Have a word with Track V Road as they were very helpfull when I had problems.

[TOPTON]

B@man said:

Sorry for the Thread Hi-Jack.
Anyone know what the standard poundage is for 400SE rears ?
Mine are too soft and it's bottoming out.

Phone RT Racing, he did tell me that supplying standard springs is no problem. He just didn't have what I needed for coilovers.
I read somewhere that 175lb was correct for the back, but going by what I read for the front, that could be wrong too

[GV]

Which make of coilovers are they? The reason why I ask is because the makers should be able to supply stiffer springs to fit.

[TOPTON]

I have AVO adjustable coilovers. I knew I could buy suitable springs from where I bought them, that wasn't the problem. Spring rate was the problem that coilover suppliers couldn't help with. A wedge being a special model and all that.
Unless the lower arm is adjusted/strengthened exactly the same way on every car, then the spring rates will differ. As the angle of the shocker is important, 1/2" difference in mounting point can alter the spring rate needed. Thats another reason RT couldn't be exact on spring strenth, they didn't have my new dimensions

[B@man]

TOPTON said:

B@man said:

Sorry for the Thread Hi-Jack.
Anyone know what the standard poundage is for 400SE rears ?
Mine are too soft and it's bottoming out.

Phone RT Racing, he did tell me that supplying standard springs is no problem. He just didn't have what I needed for coilovers.
I read somewhere that 175lb was correct for the back, but going by what I read for the front, that could be wrong too

Thanks,

I think the springs that are on came from RT, I'll give Richard a call next week.