Monospring Purpose

[Space Cowboy]

Hello All,

It looks like somewhere down the road my 68 leafspring was replaced with a monospring. What is the main purpose of going with a monospring? Is it a softer ride or what?

Thanks!

 

[81 Corvette]

weight reduction = fiberglass < steel

 

[Vettehead Mikey]

Not necessarily a softer ride, that depends on the spring rate, but certainly a more compliant ride - the mono springs have much less internal friction that inhibits the stock spring from reacting to smaller bumps in the road.

Most owners find that the stock shocks feel to soft and spongy or gives a 'pogo stick' ride after switching to a monospring. I've new Delcos on my car and they are not adequate.

 

[brusso]

I think that the monospring maintains its spring rate (lbs per in) better over the years.

 

[Space Cowboy]

Thanks all... I think that about explains it.

 

[00fxd]

Mikey;
What spring rate is your Glass spring? I have experienced the "pogo stick" effect in my friends '65 With Glass Spring/Bilstiens. I don't like it. What I don't understand is why the '79-'81 Corvettes don't bounce-and they used the glass springs. The Delco shock catalogue shows the same shocks from '65-'80! My delema is which Bisltiens to buy, the "Sport" or the "H.D.s" to prevent this bounce when I switch to the FibreGlass spring in my '65. I have ordered the "Sport". Hope I'm right. The suppliers all kinda waffle when I put this to them.

 

[Chris Kennedy]

There is lots and lots of propoganda out there on shock absorbers. I have an '81 4-spd with the Vette Brakes medium rear spring and 550 fronts, and think I know the pogo stick effect you were talking about. My recommendation would be to go with Monroe Sensatrac. Hardly an exotic brand, but the best in my experience for a "flat" ride, and I have tried Bilsteins (o.k., but really overrated and over priced), KYB (they had the most pogo stick effect) and Koni (o.k., but really difficult to adjust). Frankly, I also think there is lots of propoganda out on the monosprings, too. Finally, something you might try is lowering the tire inflation pressure just a bit---between 27 and 30. That will build a little compliance into the suspension, and on "real world" roads you will actually find yourself being able to corner better since you won't be skittering and bouncing as much. Just try it and report back.


--Chris Kennedy
Houston, Texas

 

[00fxd]

Thanks Chris;
What is the diff between the mono spring that was original to your car and the Vette Brake unit you replaced it with?

 

[Chris Kennedy]

My '81 had a metal spring when I got it, and I replaced it with the monospring soon thereafter. I did not drive the car with the metal spring too long before changing it, but frankly I didn't notice that much of a difference between the two springs. As to monosprings, if I did it again I would go for the TRW spring, since it comes with the heat shield. I talked with VBP about this, and they claimed that their spring was o.k. so long as there were a couple of inches between the spring and exhaust (apparently, the spring goes just flattens out if it overheats---doesn't break). Still, I would prefer to have the heat shield to protect both spring and differential from heat. In tuning these cars for handling, try to get a "flat" ride with some compliance but with control---people over spring and over anti-roll bar these cars, and they skitter all over and go slower around corners because of this. I went down one "notch" in the rear from Vette Brakes slalom kit---it was over-barred and sprung at the rear. Try also to dial in handling that is neuteral to slight understeer. This will reduce some of the car's overboost steering twitchiness, and will steady out the car and avoid nasty oversteering episodes when you least expect them.

--Chris Kennedy
Houston, Texas

 

[Vettehead Mikey]

Mikey;
What spring rate is your Glass spring?.

Mine is the middle of the range spring rate. I think it's 355 lbs(?)

 

[00fxd]

I thought that by '81 all Corvettes had the monospring.
Would it be a good idea to build your own shield to wrap around your spring?