Spitfire 1500 Suspension/ Ride Height

[hardhatharry]

the tub is about to come off so I thought its time to properly look at the suspension. My daily driver is an MG TF so I'm not exactly used to plush handling more crash/ bang but sticks to the road.

I'm looking to loose an inch in the ride height and I believe thats optimal according to various threads but how do I achieve this?

I have read about changing the spacers but I dont know what spacers to get and where to get them from for the desired effect. I have found a rear lowering block 1" on a couple of sites I assume thats what I need.

I'm also assuming I will need shorter front springs and height adjustable dampers, can someone recommend what springs and economical dampers (approx £100 a side, I cant afford Konis)and where is the best place to get them? Is there a spacer involved in the front??

I have adjustable AVO's on the rear, new old stock.

 

[Clive]

Moss have some info on alternative length springs and give an expected spring length once fitted (useful, unlike saying "uprated" or "lowered" as you know what you will be getting)

At the front you can fit spacers if you find the springs are too short, or even fit adjustable height dampers. For most spitfires, a 330lb spring will work well.

At the rear, yes a lowering block will do what you want. Don't forget longer studs, or, if a 1" block, you may find bolts are better as they won't stick up as much.

[GT6M]

Ello Harry,  Im always scepticle of just lower,n car, either frunt or back wid standard dampers fitted

most ev got a cover over em, this cover hides what ye really need t,see.

which is hoo much free space ye got for bump.

 

If ye lower car wid standard  shocks and lower springs, then its gonna be ont bump stops alot of the time, which will seriously effect yer cars handling

ie, supension going solid, so ye tyres then become the shocker, !!

 

If lowering the car, then ye need t,go stiffer, muchess stiffer infact on the fronts,

but ye dont say what car it is,

if its a GT, and on skinny tyres,  then 650-750,LB,ers minimum, and 8-9 inch springs

on a inch lower shocker height.

cant say aboot a Spitty, as never really tinkerated wid em as much

 

but problemos start here cos the aftermarket shockers aint designed for 500lb + springs

nor ,in my findings / use,   have the correct bump re bound settings

they too stiff on bump, and no so much on rebound, which causes weird porpoising at speeds

 

Ye need t,get em re valved, aboot 20-25 a go. for the springs yer use,n

 

Most will be fine for upto 450, after that, the clicks just dont doo owt at all .

esp on higher rated springs

 

The rears OK ive found, on Gaz,s adjustable,  Avos wer a little too hard on lower settings, so too wer Spaxs, the Gazs i got on rear are on 5 clicks, on a GT

the AVOs wer on 0 so too wer spax, nee good at all.

15 clicks an only used  no clicks, , thats not an adjustable shocker t,me.

 

Butt, all depends on what speeds yer dooing, if just normal pottering speeds, then they be OK,

 

summary for a GT on skinny tyres

650-750 springs wid 8 inch free length

1 inch shorter shockers

and yer dampers re valved

 

done right, the stiff springs will be a softer ride than most 330 or 440 thats offered thru the

usual suspects.

[John Harris]

Harry

Below are two articles to read. The first gives the basics, the second the data you need.

http://auskellian.com/paul/links_files/performance_enhancements.htm - Basics

http://auskellian.com/paul/links_files/springs.htm - suspension data

Be careful with spring suppliers. Moss and Rimmer Bros quote spring rates of 150 Lb and supply springs with 12 coils for 1500. On a 1500 with standard shocks, including Koni's it will become coil bound. SC parts quote 180 Lb and 11 coils, works much better. 

If you want to lower the suspension you will need a higher poundage  and less coils combined with a short action damper. The articles talk through the geometry front and rear. 

I run SC parts 180 Lb on the front with Koni shocks, shimmed for negative camber.

On the rear I run a standard leaf with a compression/lowering block, with UHMW polyethylene thrust washers made to the spec in the article with Koni dampers and adjustable radius arms.

I also have an MGB GT V8 which runs Gaz rear shocks. Koni and Gaz both work well. Not too hard on the lowest settings.

 

 

 

 

 

[Mjit]

From experience I'd recommend a 3/4", rather than full 1" lowering block - especially if you have a sports exhaust fitted.  Tried a 1" block and they are a literal pain in the ass - you just find yourself clentching your buttocks every time you see a speed hump/pothole/etc, waiting for that scraping noise 😥

Swapped to a 3/4" and only need to watch out for grounding when the boot's fully loaded.  A much better match height-wise to you (I think TSSC Shop) upgrated front springs too.

[hardhatharry]

Yes I do have a sports exhaust