400SE rear springs

[B@man]

After the fosse way turned into a white knuckle ride I've finally admitted that the rear springs need replacement as they are far too soft, combined with half of Sue's wardrobe in the boot the car was bottoming out, crashing over bumps and and a nightmare to control.

Anyone have any idea what the spring rate is for the 400SE ? as far as I know it's got standard springs over protech shocks fitted with adjustable platforms as fitted by RT racing some years ago.

[wedgeman]

I would give Richard at RT Racing a call again- he should have them in stock

[chj]

wedgeman said:

I would give Richard at RT Racing a call again- he should have them in stock

+1

Replaced my 400se front springs when one cracked. He's definitely the man to call.

[Convert]

The speed we were going down the Fosse way, even my Golf was having trouble with the bumps...

However Richard @ RT is the man.

[dixiebabes]

^^^^^^ same as this i replaced mine with a pair from RT racing.

Dix

[B@man]

Thanks gents,

A pair are on their way from Sheffield.

[Danny Hoffman]

I'd check the shocks carefully whilst you have it in bits, you may find they are contributing to your problem

[B@man]

Hi Danny,

I hope not they where replaced under warranty three years ago after the first set cracked !
Thanks for the heads up though.

[adam quantrill]

If by "bottoming out" you mean that the exhaust was grounding or the wheels were hitting the insides of the wheel arches I have had some experience of adlusting this.

When I went to wider wheels/tyres on the back of the 400SX (same body as yours) I found that it was more prone to the tyres hitting the arches under full suspension deflection. I also noticed the northward journey on the Fosse causing the exhaust to ground at speed with two up and all the missus's clobber in the boot.

So I embarked on a programme to rectify this but without knackering the existing suspension (thanks to Leigh for the suggestions). The wheelarch problem has been largely solved by packing out the body mounting rubbers to even up the "two finger gap" on both sides. Also I added some Aly shims inside the shock absorbers because the bump stops inside are not adequate to stop the suspension movement before it's too late.

This made some improvement to the grounding-out of the exhaust over the Fosse undulations. To make it ride them perfectly I would increase the damper rate next, rather than the spring rate, which will prevent the wheels rising too fast. However as it only happens once a year (and mainly on the northbound direction) I'm not that bothered to do any more to it.

[B@man]

Hi Adam,

Thanks for the info, maybe using the A45 is a better option. wonder where Tricky's 3rd gear went...

To be fair the ride at the rear has been terrible since I got the car but as usual there was always something more interesting to play with (engines & electronics). The rear is really soft and I have problems with the car crashing over rather than riding bumps on any surface that's not like a snooker table, and the ride height is OK (well lower at the front would be better but that fixed - for now) until you put any load on board and then half the suspension travel has gone so I believe its that the spring are just weak. I can't see any evidence of tyre arch contact but could have when I get the 16's on....

I had similar problems with my last kit car and despite the manufacturer saying you need longer shocks, different trailing arms etc. etc I found that £40 worth of coil over springs transformed the car ! Anyway hopefully the springs will be here by Friday and I can see what's what over the weekend once I've serviced Sue's crappy Peugeot....

[adam quantrill]

B@man said:

the ride height is OK (well lower at the front would be better but that fixed - for now) until you put any load on board and then half the suspension travel has gone ....

Yes - that's the springs. Remeber what I said for afterwards and you get your 16" rims on tho...

[Trickie Dickie]

B@man said:

Thanks for the info, maybe using the A45 is a better option. wonder where Tricky's 3rd gear went...

I have watched back the in car vid I had on and the 3rd gear disappeared as soon as we got on the Fosse Way.

By the first junction it had gone!!!!

We didn't go fast at all (in my book) as 3rd is definitely the main acceleration gear

It was also a bit bouncy in my car as just had the spring and shocks done
and they are set far too soft

We came back up the motorway as couldn't afford to loose any more gears

Cheers
Trickie

[B@man]

Well That went well....

Ordered a pair of springs from RT and last night got one of the old ones off and they are exactly the same length and spring cross section, further tests using a selection of weight plates also confirmed that they where no higher poundage either. Will speak to RT again tomorrow but to say I'm hacked off is an understatement as after fully explaining the situation he sent me the same as I have already. As a temporary fix I've upped the spring platforms putting more pre load on the existing springs, increasing the rate slightly and gone another 4 clicks on the dampers. Looks stupid but at least it should be more stable.

Seriously considering piggy bank raid and a visit to TvR....

[Transmitter Man]

Do you know the spec of the RT springs?

I am having a complete new set of Gaz Gold adjustable shocks & springs fitted shortly so you may wish to give them a call re 'their' suggested spring rates just for a second opinion.

Phil
420 SEAC

[V8 Fettler]

I've used http://www.coilsprings.co.uk/ to make coil springs for something that wasn't a TVR. They seem to have a lot of experience.

[B@man]

Hmm Sheffield.... I wonder if that's where someone else gets their springs....

E-mail sent !

Thanks