Does anybody (eg. with a workshop manual) know what the spring rate is for standard 164 front springs ?

I am in the process of putting some in the front of my 142 (temporarily, so I can get the 142 springs properly measured & rated etc before I buy something more permanent for the front) & I am just curious as to how much stiffer - if any - the 164 springs are.

Dave

Dave,

The 164 front springs are 360 lbs/in, compared to the 140 fronts at 305 lbs/in. The data was extrapolated from the 1970 and 1971 workshop manuals for the 164 and 140, respectively. I'm relatively certain the 140 front spring rates were the same from the start of production all the way thru 1974. I would therefore think it unlikely that the 164 springs would have been changed from the 1970 specification at any later point in production.

Given the approximate 20% higher spring rate, I would expect a noticeable increase in understeer (or decrease in oversteer) with the 164 front springs, assuming no other changes. It will also most likely sit slightly higher in front, and obviously ride slightly stiffer.

Gary L.
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1971 142E ITB racer, 1973 1800ES, 2002 S60 T5

Do you happen to know the motion ratio of the 140/164 front suspension? Just curious what those rates work out to be at the wheel.

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forums.turbobricks.com
Parting out '84 DL auto, many cheap parts available

"Do you happen to know the motion ratio of the 140/164 front suspension? Just curious what those rates work out to be at the wheel."

The wheel rate on a 140 is .28 times spring rate. This is based on the following dimensions:

Inner pivot to center of spring = 8.5 inches
Inner pivot to ball joint = 16.0 inches

So we should end up at approximately 85 lbs/in with the 140 spring, and about 101 lbs/in with the 164 spring.

For those who give a durn, my 142 race car is currently on 800 lbs/in front springs, resulting in about 225 lbs/in wheel rate.

Gary L.
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1971 142E ITB racer, 1973 1800ES, 2002 S60 T5

Wow. I'd heard it was roughly .25x for the wheel rate, but that just seemed too low. 220 is pretty soft compared to the 475's I'm running on the front of my 240. And I'd like to go higher still!

What about the rear? I usually hear 150-200lb rear on a itb142...
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forums.turbobricks.com
Parting out '84 DL auto, many cheap parts available

"220 is pretty soft compared to the 475's I'm running on the front of my 240."

Yes it is, since you are at essentially double my wheel rate. But we're getting into a classic apples and oranges comparison here... double a-arm vs Macpherson strut. I've never been around a 240 set up for competition, but I guess I'm not surprised that you'd have to run a much higher wheel rate.

And actually, I was mistaken about the front springs in my 142, they're softer than I quoted; I'm currently running 700's in the front (195 lbs/in at the wheel). I do have a pair of 800's for the front, but the car is currently on the 700's. At the rear I'm currently on 225's, with 2 other pairs for tuning purposes, at 250 and 275 lbs/in.

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1971 142E ITB racer, 1973 1800ES, 2002 S60 T5

Thanks Gary - much appreciated !

Being a rally car (or sorts) a little extra ride height doesnt faze me - I think they are about 1" taller unladen than the 140 springs ? It's getting some slightly stiffer springs in the back too so should even out OK.

Mot of the guys rallying 140s over here are running front springs in the 475-550 range, but I don't want to go quite that hard. Should help control some of the front-end "wallow" if nothing else !

I'll see how they go ...

"I think they are about 1" taller unladen than the 140 springs ?"

I do not have the unladen height for either spring, as that information is not in the manuals. But I would be a bit surprised, based on other data in the manuals, to learn there was actually much difference between new springs, if any difference at all. My comment about the higher ride height was based solely on the effect of the 20% higher rate of the 164 spring, not on unladen height.

Gary L
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1971 142E ITB racer, 1973 1800ES, 2002 S60 T5

Don't know the rates but the 164 springs are significantly stronger than the 140 springs. There's 50% more engine and a longer nose to support with the 164. The crossmember design is essentially the same between the two cars.

In my opinion it never was beefy enough for the 164- my wife's first car, a 75 164, used to chew up idler arm bushings like they were candy.
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Rob Bareiss, New London CT ::: 87 244DL- 249K, 88 245DL- 181K, 84 242DL, 89 244DL parts, SOLD: 86 244, 88 244GL, 87 244, 91 244, 82 245T, 88 744GLE, 86 244

Gary

Measured the 140 springs that came out of the car last night, and the free length is 12". This is the same as what the 164 springs I put in were, from memory.

I just had it in my head that someone (Fidel, maybe ?) had posted a while ago that the 140 springs were 10.5" ...

The car is certainly sitting higher than it was in the front - looks a bit strange at the moment, with the high-ish ride, stock 165x15 tyres, and a couple of degrees of neg camber :o). Drives well though - the additional stiffness is welcome, and there is no hint of excessive understeer on bitumen. Handling seems very neutral, in fact. Will be interesting to see how it goes on the dirt next weekend ...

I am sure it will "settle" fractionally over the next few days anyway as the new poly bushes all round work themselves into equilibrium etc ... and will be better with the 196/65 rally tyres or the 205/65 road tyres (on Virgos) when they go on it next week.

It probably needs to be a tad lower than it is, ideally - I will hunt around for some appropriate springs longer term.

yep,140 front springsare 10.5" got three sets in the shed. and the rate i got from the dyno was 300# with an inch of pre load.

hope it handles well for ya on the dirt.

if you need front springs in different rates and hightes
try


http://www.stockcarproducts.com/springs.htm

they have hights available from 8.75 to 14".

Fidel

Well these ones are 12" free length, and they were the original springs as far as I know (everything else on the car is original/stock, & I see no evidence that the front springs are not). I measured them from the flat surface on each end.

Maybe it's just a model year &/or market difference (it's an Australia-assembled late 1974 model)?

Importing springs from the USA isn't an option, but there are plenty of places around that will find something appropriate for me in due course.

Dave

all mine came out of 73-74 us 140's. might be a maket thing.

oh, in oz. yeh shipping would be a bit much. like you said there are plenty of spring companys down under.

Jumboz and King to name a couple... Anywho, have you considered cutting the 164 springs? That'll lower the car down a little, as well as increase the spring rate a bit to get you closer to what the other guys are running, without going as high as they are, and for cheap.

Or grab some really stiff front springs from some double a-arm american car (or the aussie/nz equiv.). more weight = more spring.
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forums.turbobricks.com
Parting out '84 DL auto, many cheap parts available

Yep, understand all that .. they are stiffer, but probably not as stiff as they "should" be.

What I want is the lbs/in number .... :o)

....and I thought my 144 was hungry for those bushings...
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...and the bricks keep on rolling

They are the same bushings used by the later 122s.
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George Downs Bartlesville, Heart of the USA!