PDA

View Full Version : Making The Smoothest Riding Street VX - Tire & Shock Advice...



TheGanzman
02/09/2009, 04:14 PM
O.K. guys, finally scored me a mint 58K highway mile '01 Proton garage queen. It's stone stock, except for a set of BF Goodrich Long Trails in 265/60/18. No, I ain't gonna be lifting it or taking it to Moab; it's gonna be my daily driver - freeway runs up to L.A. once per week, and schlepping my trail bicycle to and from my bike trails. Here's my questions:

I'm leaning towards a set of General Grabbers in 265/60/18; they're getting great reviews all around as a good all-season SUV road tire. In the opinion of the more learned members of the group, will the slightly larger profile of the 265 ride more smoothly than the stock 245?

For those with experience with the Rancho RS9000XL's who have replaced the stock shocks that were in DECENT condition, was there a noticeable improvement in ride quality? How "low did you go" on the dial settings for highway use? Do they ride better than the equivalent Bilsteins?

I've already read a PILE of threads on shocks and tires, but have yet to see the definitive thread on THE best choice for highway shocks and tires. I realize that we're talking about a stoutly-sprung, short wheelbase SUV; I'm not expecting a Coupe de Ville - just trying to get the max. comfort out of the limited constraints that we're working with...

BTW, I SURE do like that I'm NOT driving a Honda CRV, Toyota RAV4, BMW M3, Infinity EX35, VW Tiguan, Mercedes GLK, Lexus RX, Land Rover LR2, Subaru Forester, or Acura RDX! I researched the sh*te outta ALL of 'em; couldda bought ANY of 'em - and I'd rather own my "new" VX than the best of the above!

Thmstec
02/09/2009, 04:35 PM
Smooth riding VX :_wtf:?

Sarcasm aside, I don't have any experience with new shocks or tires. But understanding the physics behind it, the bigger tires will ride smoother, assuming that the side-walls aren't dramatically stiffer...

As an additional thought though, I notice you got an '01, and those have the 18inch rims. Moving to some smaller [16inch] rims would improve the ride quality a bit. Especially if you do some large 265 tires which would require none to minimal trimming of the cladding. Just as a note though, my '99 VX (16 inch rims) came with 255 all-terrains (stock 245), stock shocks, and I would say it rides pretty rough. Especially when the tires are pumped up properly.

Some softer shocks would probably make the most difference in "ride quality." Just keep in mind that your VX will dip/dive/lean more, which will take away a bit from the "sports car" feel. From what I've read, almost nothing is as firm as the stock shocks except for a select set of bilsteins

pbkid
02/09/2009, 05:15 PM
Smooth riding VX :_wtf:?

Sarcasm aside, I don't have any experience with new shocks or tires. But understanding the physics behind it, the bigger tires will ride smoother, assuming that the side-walls aren't dramatically stiffer...

As an additional thought though, I notice you got an '01, and those have the 18inch rims. Moving to some smaller [16inch] rims would improve the ride quality a bit. Especially if you do some large 265 tires which would require none to minimal trimming of the cladding. Just as a note though, my '99 VX (16 inch rims) came with 255 all-terrains (stock 245), stock shocks, and I would say it rides pretty rough. Especially when the tires are pumped up properly.

Some softer shocks would probably make the most difference in "ride quality." Just keep in mind that your VX will dip/dive/lean more, which will take away a bit from the "sports car" feel. From what I've read, almost nothing is as firm as the stock shocks except for a select set of bilsteins

thats what i was thinking.... the VX is kinda heavy in the front and so (at least mine) has a tendency to dip when braking and lean in the front when cornering (yes my shocks need a little replacing, but they definately arent blown)....so in my experience, if you replace them with something softer your going to end up with something that handles like a cadalac (sp)....

i would take thmstec's advice and go with a smaller rim...which will give you more sidewall which will in turn give you a softer ride, but still have good response...

so, i would stay stiff with the shocks and get a bigger sidewall...

Gussie2000
02/09/2009, 05:39 PM
I'll deffinetly go with smaller rims,also remember that the tire's speed rating is important along with the index load.

An set up of highway/all season should be just perfect.If you need more info check out tirerack.com.

You can gather all the info to make the right choice

pbkid
02/09/2009, 06:51 PM
I'll deffinetly go with smaller rims,also remember that the tire's speed rating is important along with the index load.

An set up of highway/all season should be just perfect.If you need more info check out tirerack.com.

You can gather all the info to make the right choice

personally i LOVE the bfg all terrain's...but i drive 8 hours a week solid in the snow....so i need something that kicks arse...

rowhard
02/09/2009, 06:57 PM
The Rancho 9000's will soften the ride over the OEM's, but being a short wheelbase, it will still and always be an uncomfortable ride compared to a long wheel base vehicle. I found with 9000's, when run soft, had a lot of nose dive under braking.

etlsport
02/09/2009, 07:26 PM
i drove a vx with gabriel shocks and it rode really smooth.. also as pbkid mentioned there was lots of body roll so it didnt handle sharp turns nearly as well as my stock shocked VX... dont know what model they were.. just that they were gabriel shocks

here is the only listing for them ive found on this site.. so might be these

Trooper listing
Ultra Premium SUV
P/N
Frnt G63707
Rear G63708

nfpgasmask
02/10/2009, 09:04 AM
Mmmm, if you go with smaller rims, I would get a nice set of 16" American Racing Teflon Mojaves. I keep waiting to see a Proton with those rims. Maybe someday I will have to buy a Proton and do it myself. :rolleyes:

Bart

TheGanzman
02/10/2009, 09:33 AM
Mmmm, if you go with smaller rims, I would get a nice set of 16" American Racing Teflon Mojaves. I keep waiting to see a Proton with those rims. Maybe someday I will have to buy a Proton and do it myself. :rolleyes:

Bart

Actually, I'd go with some American Racing Torq Thrust D's in 16" (Old School, doncha know...) - I'd just have to figger out how to go from 6 lugs down to 5 (custom spacers) and work out all the offset math...

rowhard
02/10/2009, 05:00 PM
Actually, I'd go with some American Racing Torq Thrust D's in 16" (Old School, doncha know...) - I'd just have to figger out how to go from 6 lugs down to 5 (custom spacers) and work out all the offset math...
You might have even more of a problem with the center bore, you need at least 100mm, almost 4 inches

PHO2GR4
02/11/2009, 04:12 PM
AR Teflon Mojave OR Teflon Chambers. They'd look great with a Proton paint job.

And you can use them to cook eggs in Moab!

Oh, and the Rancho shocks give a much smoother ride, with less-tight handling. There will always be a comfort vs. performance trade-off.

TheGanzman
02/11/2009, 06:10 PM
AR Teflon Mojave OR Teflon Chambers. They'd look great with a Proton paint job.

And you can use them to cook eggs in Moab!

Oh, and the Rancho shocks give a much smoother ride, with less-tight handling. There will always be a comfort vs. performance trade-off.

Thanks for the response! Assuming you have the Ranchos, what have you found setting-wise is the best all around compromise in terms of handling/comfort?

PHO2GR4
02/12/2009, 12:12 AM
Thanks for the response! Assuming you have the Ranchos, what have you found setting-wise is the best all around compromise in terms of handling/comfort?

I do indeed have the Rancho RS 9000 shocks all around. I put them on the softest setting right after installation, just to feel them immediate difference VS the old shocks. Then I liked the ride so much that I never changed them to a stiffer setting!

I suppose one day I could dial them all the way to the stiffest setting for comparison's sake, but I'm just too busy. Ummmm, I mean, lazy. :cool:

VehiGAZ
02/16/2009, 07:40 AM
You can make the ride less harsh with softer (or adjustable) shocks but the real culprit of the VX's bucking-horse ride quality are the springs.

To the chalk board...

A vehicle rests on its springs, and the shocks dampen the springs' motion. If you have shocks too stiff for the springs (or springs too soft for the shocks), the shocks do not yield and you get a very harsh ride. If the shocks are too soft for the springs (or the springs are too stiff for the shocks!), then you get a softer ride but with too much bouncy motion from the springs (i.e., not smooth). Ever seen the tail of a lowered Civic bouncing up and down short and quick while driving on a relatively smooth highway? That's because they put shorter, stiffer "lowering" springs in without replacing the OEM shocks, or they replaced them with shocks that are totally outmatched by the new springs. Don't be one of those guys!!!

It's important to remember that shocks don't hold the vehicle up - even gas charged shocks do not support a vehicle - they just have a higher rebound force than compression force. The springs support the vehicle and want to make it bounce - properly-matched shocks will counteract the springs' tendency to bounce.

I bought my VX with not-up-to-the-job KYB Gas-A-Just shocks, and it was almost undriveable on very bumpy roads - there was so much up-and-down motion that I thought it was going to leap off the road. I replaced them with Bilsteins which provided good control of the springs - very comparable to the stock shocks, but the stock ride was never buttery.

Additionally, body roll has almost nothing to do with shocks at all. Sway bars and springs control body roll, and the springs control brake dive pretty much by themselves - the shocks are barely involved in controlling dive at all.

So... if you want to make the ride softer and smoother, the best way would be to find softer springs and adjustable shocks dialed in to match the force of your new springs.

Unfortunately, I don't know that anyone has replaced the OEM VX springs with something a little softer. Anyone know what the spring force is on a Trooper or Amigo's springs and if they will fit the VX?

TheGanzman
02/16/2009, 08:53 AM
Agreed about the springs, and I'm sure that Trooper springs are prolly an R&R, and also softer. I'd be MORE tempted to pull a stock front and rear spring from the VX, and send 'em off to a spring winder to have the stock springs evaluated, and a new custom-wound Variable Rate set made for me. I've already committed to buying a set of stock 16" wheels from another member; that should help some (plus personally, I think the polished aluminum and the style of the '99's looks better on any VX). I probably WILL also switch to the Rancho RS9000XL's; I like the idea of the adjustability (And NO, I WON'T be selling the stock shocks!). BTW, the General Grabber HTS is getting rave reviews for a street tire; got myself figgered for a set of those too!

VehiGAZ
02/16/2009, 03:48 PM
I'd be MORE tempted to pull a stock front and rear spring from the VX, and send 'em off to a spring winder to have the stock springs evaluated, and a new custom-wound Variable Rate set made for me.

That would be the best idea of all - all science, no guess work!

PK
02/16/2009, 05:26 PM
Wow - yep you guys are right on the money.

Just whip those front springs outta there are get new ones wound up with a progressive rate.




Errrrr - where those springs gone now.:confused::confused:
I don't see any.

Can you get them there torsion bar thingies wound???:bwgy::bwgr::smilewink

deermagnet
02/16/2009, 06:11 PM
If you were looking to get some new springs fabbed, this is info on the stock '99 springs.

Front torsion bar springs-
Diameter- 1.14"
Length- 47.95"
Wheel rate- 3.73 kg/mm
Capacity- 1097 lbs.

Rear coil springs-
Free height- 15.83"
Wire diameter- 0.41-0.53"
Coil caliber- 4.14"
Effective number of turns- 9.18
Total number of turns- 10.68
Wheel rate- 4.8 kg/mm
Capacity- 1238 lbs.

The fabber would probably wanna see these '99 figures also.

Curb weight- 3955 lbs., 2026 lbs. front, 1929 lbs. rear
Loaded weight- 4255 lbs., 2146 lbs. front, 2109 lbs. rear
Gross vehicle weight- 4652 lbs., 2176 lbs. front, 2476 lbs. rear
Gross axle weight- 2194 lbs. front, 2476 lbs. rear
Gross payload- 697 lbs.

Mark

TheGanzman
02/16/2009, 07:16 PM
PK is right, no coils on the front; I guess you live with it the way it's "sprung" w/the torsion bars...I'd be inclined to just try rear Trooper springs, since I seem to remember reading that they're sprung softer than the VX...

VehiGAZ
02/17/2009, 07:00 AM
Wow - yep you guys are right on the money.

Just whip those front springs outta there are get new ones wound up with a progressive rate.

Yeah, yeah, yeah... whatever. :rollb:

Whether it's a spring or a torsion bar, the same principles apply (although I guess I don't know if someone out there makes new torsion bars to spec).

The VX is sprung (and barred) too stiffly for it to have a smooth ride, regardless of what type of shocks you put in there. If you want a smoother ride without bounce, you're gonna have to do something about the springs & bars first.

Good luck!

deermagnet
02/17/2009, 07:38 AM
It looks like you can get custom made torsion bar springs and coil springs to your exact specs to whatever you need to smooth out the VX ride. A few minutes on Google shows lots of choices.

http://www.kdkforging.com/torsion_bars.php (http://www.kdkforging.com/torsion_bars.php)

When ordering, don't talk spring rates. The wheel rate is the only thing that matters. You now know the wheel rates for the front and rear stock '99 springs. Order 'em, install 'em, BAM you're done. A custom VX ride to your exact needs and wishes.

Mark Griffin

VehiGAZ
02/17/2009, 08:18 AM
It looks like you can get custom made torsion bar springs and coil springs to your exact specs

Ta-DAH!!!!


The only question remains... what specs should they be made in order to soften up the ride just right? 5% softer? 10%? 12.425%?