Super Bounce

Suspension, including wheel, tire and brake.
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Jewosh
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Super Bounce

Post by Jewosh » 21 Oct 2010 22:36

Hi,
I recently bought my first 510, a 1972 Wagon. The guy I bought it from had it lowered on the stock suspension... with cut springs up front, and a huge lowering block on the rear leafs. When I test drove it from him, it bounced a little, but we must have been on smooth roads because around my neighborhood, it bounces and bumps all over every little thing. Not only is it uncomfortable, it makes it really hard to control on turns if I hit a slight bump, and it chirps the tires in U-turns because it bounces around too much.
Now, is it because of the shocks being worn or just not in proper position due to the cut springs or lowering blocks, the spring rates in general, or both?
Also, what is a good but inexpensive (I'm still a student) setup for a wagon?

Thanks
Josh

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bertvorgon
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Re: Super Bounce

Post by bertvorgon » 22 Oct 2010 06:22

That sounds like a classic case of totally dead shocks....if there are any there.... :lol:

If it has been severely lowered in the back, you will want to make sure that the shocks do not bottom out too. You are primarily talking about the rear, right?!
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1968 Vintage 3HP Mini Bike
1971 Vintage 13' BOLER trailer

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okayfine
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Re: Super Bounce

Post by okayfine » 22 Oct 2010 07:15

Jewosh wrote:Now, is it because of the shocks being worn or just not in proper position due to the cut springs or lowering blocks, the spring rates in general, or both?
Yes.

As to the rest, define "inexpensive." And what you want from it. And your mechanical abilities (i.e. can you change struts out yourself, etc.).
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson

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vgwagon
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Re: Super Bounce

Post by vgwagon » 22 Oct 2010 11:05

Huge blocks in the rear will have you on the bump stops if they are 3 inches or more and that will make your car bouonce no matter how good your shocks are.
Blocking the rear doesn't affect rear shock travel.
Make sure you are not sitting on the rear bump stops as a first check.
Denis Gagné
AKA VGwagon

69 510 VG30e swapped
73 240z VG30et swapped
86 300zx na2t VG30et converted

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jason
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Re: Super Bounce

Post by jason » 22 Oct 2010 11:41

Josh, I ran 2" lowering blocks, new HD KYB shocks in the rear with an extra leaf and stock, re oiled to 20W dampers in 1968 510 short struts and very heavy 200+ lb springs on the front of my Blue wagon and it felt very good. I also had a 1" front sway bar up front and no rear bar. I'd probably change that back to a stock front bar to compare as it had a ton of oversteer ....
Jason

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vgwagon
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Re: Super Bounce

Post by vgwagon » 22 Oct 2010 14:11

jason wrote:Josh, I ran 2" lowering blocks, new HD KYB shocks in the rear with an extra leaf and stock, re oiled to 20W dampers in 1968 510 short struts and very heavy 200+ lb springs on the front of my Blue wagon and it felt very good. I also had a 1" front sway bar up front and no rear bar. I'd probably change that back to a stock front bar to compare as it had a ton of oversteer ....
Changing your front bar to something smaller would only make oversteer worse if my understanding is correct. A bigger front bar should induce understeer as compared to oversteer. A big rear bar would create oversteer.
I'm sure his problem starts with the huge lowering blocks and uncut bump stops. I know with the 3 inch blocks I had it made the rear of the car to bouncy for my liking and I cut the lowering block down to 2 inches, then it was fine.
Denis Gagné
AKA VGwagon

69 510 VG30e swapped
73 240z VG30et swapped
86 300zx na2t VG30et converted

Jewosh
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Re: Super Bounce

Post by Jewosh » 22 Oct 2010 17:19

Yea, I haven't measured the blocks yet but I'm guessing they are close to three inches. The back bounces a lot, but the front is really bad too. It's super stiff if I push on it, but when I do, it just bounces and bounces around. So I'm guessing the shocks are just basically done.

I can change all the parts myself (a friend has a shop) but I don't know how well I would be able to modify parts to fit...

What do you recommend for the front suspension? A 240zx swap?

and for the rear, I was thinking of stiffer leafs and a better shock.

Thanks!

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vgwagon
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Re: Super Bounce

Post by vgwagon » 23 Oct 2010 09:45

Replace the shock and strut inserts first.

Then drive it and see how it feels
Denis Gagné
AKA VGwagon

69 510 VG30e swapped
73 240z VG30et swapped
86 300zx na2t VG30et converted

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okayfine
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Re: Super Bounce

Post by okayfine » 23 Oct 2010 11:30

vgwagon wrote:Replace the shock and strut inserts first.

Then drive it and see how it feels
This. You don't know what you want because you haven't driven a 510 that doesn't have a shot suspension. Replace what's faulty. There's all the time in the world to upgrade, and you have much research to do to figure out what you want to upgrade to, if anything.

You are probably going to want to lift the car an inch or so, just to keep it off the bumpstops and give you some suspension travel. 2" blocks in the back and a commensurate lowering for the front will help out and shouldn't destroy shocks and struts too quickly.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson

Jewosh
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Re: Super Bounce

Post by Jewosh » 11 Jan 2011 21:43

I ended up doing a 280zx front conversion with new coilovers and in the rear new shorter shocks, flipped the bottom leaf, and now have a 1' lowering block and it is so much better. Driveshaft never scrapes anymore and I can finally have people in the car without it scraping over everything or the driveshaft threatening to put a hole in the floor. Now to find a way to make the whole setup a little stiffer and have less body roll....

thanks for the help

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