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Hi

 

I've hunted around the forum but can't quite see an answer to my query. Had my 4A now for about 12 months, and on the road (MOT) for about 6 months. The PO only had the car 9 months and didn't get it on the road, but had started working his way from the back replacing items. He fitted new rear shockers, (did away with the Lever Arms) with what looks like a proper replacement bracket kit, and fitted new springs. But didn't get to the front end. I replaced brakes etc but again left the front end alone apart from Trunnions and bushes, car passed MOT.

 

However the car is "nose up" I've looked at other cars at events etc and they all look pretty level, mine is way nose up. I came across an interesting article in TRaction Dec 12, Issue 262 page 39 re upgrading the 4a & 5 suspension. The guy talks about ride heights of 685 / 690 at the rear, & 685 at the front, measured from the floor to the wheel arch.

 

Mine currently measures 660 at the rear, and 700 & 710 at the front. But, can't see why. This is based on empty car and about 50% full tank of fuel. The new rear springs look to be 8 coil, and have standard packers / spacers at top & bottom, would 9 coil be better, and how significant is the coil dia?

 

The car still has the standard Trailing Arm brackets, 1 notch inner & 2 notch outer, notches upper most, they look to have been untouched.

 

Took the car for a 130 mile run recently, uneventful, at 60mph, everything seems fine, with hands off the wheel it still goes straight, and brakes up straight.

 

Would appreciate any thoughts you might have, I need to address the front end, probably over this coming winter, but want to make sure I go in the right direction.

 

Cheers

 

Ian

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We have previous topics here where doing away with lever-arms produces broken chassis or trailing arms.

This is because the travel is insufficient.

 

You may be better going back to lever-arms.

This may quite probably make it level.

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By the sound of it you may well have lowered springs, what tyres are you running? The Moss parts book gives the free length of the various different springs. You do need to check that your trailing arms will hit the bump stops before the shocks bottom if you have the telescopic conversion. The change to telescopic shouldnt affect your ride height on its own.

Stuart.

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Ian,

 

It sounds like the PO fitted lower rear springs (probably uprated ones) while upgrading the suspension which is common practice.

As long as there is no sign of wheels fouling and you are happy with the ride I suspect you will simply need to fit slightly lower front springs to match.

 

A selection of lowered and uprated springs is available from the usual suspects and my car was also unlevel (side to side at the rear in my case.) The original springs were just tired and I went with a set of 4 from Rimmers at the very reasonable price of £84:

 

 

2 Road Spring - Front - Lowered 1" - Uprated 420lb - Part No. 213165UR
2 Coil Spring - Rear - Lowered 3/4" - Uprated 420lb - Part No. 216275UR

 

These work really well on my 4A and are not too difficult to fit.

 

Cheers,

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I don't mean to be funny but this reminds me that: http://www.oocities.org/adrio@rogers.com/Tr4/tr4_resto.htm

 

STD free length front: 261 mm / 10.1/4 in

STD free length rear : 296 mm / 11.65 in

Difference : 35 mm

 

The difference matches what is missing at the rear (690-660) and exceeding at the front (710-685) minus the car weight. Worth checking if the PO didn't made it to the front, after all....

Edited by Geko
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No receipt from PO?

 

You can find the spring rate etc here:

http://www.planetspring.com/pages/compression-spring-calculator-coil-calculator.php

You must measure the diameter of the 'wire' precisely - micrometer job. The rate varies with the fourth power of the wire diameter ( ie d^4)

 

Peer

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Hi all

 

Thanks for the quick replies, I thought I hadn't seen a receipt from the previous PO, I was given loads and I had filed them but couldn't recall a spring one.

 

However, I found one, Rear Springs purchased from Parts 4MG Triumph Cars, David Manners Group, back in August 2012. Part number TT4212 Uprated Rear Spring TR4A-6 STD. The Moss catalogue also has the same number and describes it as Uprated - Standard, 8.85 inch fitted length, rated at 420lbs. No info on wire diameter.

 

So is it still a touch low with these standard springs fitted?

 

Tyres by the way are Toyo 165 /80 / R15.

 

Paul - your Springs as you say are from Rimmer, it's a bit difficult to compare, it looks as though Rimmer quote free length uninstalled, and Moss quote free length installed.

 

Ian

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Ian

I'd measure the length of the spring on the car - check it's compressed length really is what it says on the receipt, 8.85"!

You do need to know what you have as the front springs should be in proportion to the rears, both rate and length, to get the best balance in handling.

Any coloured paint dabs visible on the springs?

Peter

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it's not impossible to fit the springs on the wrong end, there's a guy i see in the mirror who did that....at the time each step was perfectly logical...and after a few hrs looking at the result, so was the answer

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Ian,

If you go for new springs all round, beware of going the uprated spring route. They are brilliant on flat surfaces but on today's bady maintained roads the car will deflect on every little bump, with the rear leaping hedgewards in bends with a bump in the middle. Better to fit soft springs and then stiffen up the roll with hefty front and rear antiroll bars. Better ride too.

 

Peter

 

eg 250lbs front with 22mm ARB. Compatible rear setup not mentioned. Unfortuntely in Oz:

http://www.smithees-racetech.com.au/historic/triumph.html

Edited by Peter Cobbold
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