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View Full Version : Suspension experts, check this out.



MuscleRodz
02-07-2005, 09:25 PM
Lets here some expert opinions on this one. According to the site, this was just release Dec.28 of last year. Lateral loading looks ok, but I am not sure about anything else. http://www.uniqueperformanceproducts.com/ProductPage.aspx?ItemID=27
https://static1.pt-content.com/images/noimg.gif

Mike

dennis68
02-07-2005, 09:58 PM
HOLY CRAP.....5K is a ton of money for transverse mounted coil-overs in a nicely packaged assembly with a built in watts.

You could buy a very nicely built 9" for under 1500 and assemble the coil-overs and links for another 1K.

MuscleRodz
02-07-2005, 10:01 PM
Holy Crap is right. But how well do you think it will work? $5K is way out of my league. I think I could copy it for about a third of that though.

Mike

dennis68
02-07-2005, 10:04 PM
Very few builders are using tranverse mounted springs. It is more for packaging than performance. A lot of low riders use them with fast bags.

Maybe Norm or David will check in and explain linkage working ratios and how this arrangement would affect those.

baz67
02-09-2005, 07:54 AM
Clever design, but what about K.I.S.S. It looks like it would need stupid high spring rates by the way the shocks are mounted.

Brian

Fuelie Fan
02-09-2005, 12:08 PM
Many a high performance vehicle uses push or pull rod suspension systems, and done right they can offer all the benefits listed (unsprung weight, CG height, motio ratio, etc). I cannot tell hardly anything from those pictures as far as if they actually suceeded in doing it right. And, the price seems a little stiff. Unsprung weight reduction on a live axle, percentage wise, I would expect to be very small, so I question that argument when applied to this design. Like anything else, if the manufacturer could provide information about HOW MUCH the CG is lowered, how much overall weight is saved or added (lowering the CG 0.5" isn't that great if you do so by hanging 100lbs below the old CG to lower it! :)), how much unsprung weight is saved or added, before and after skidpad/slalom results, then I would be more convinced.

Parts Abuser
02-09-2005, 12:39 PM
All,
Because I had the room and am naturally curious, I did a rocker arm setup on the rear of my el Camino. My main motivation for even considering this was to allow for a semi-soft spring rate on a very low car. It's a known fact that with a rocker arm, you can very easily design in some ratio gain. I forget the numbers I used on my car but I can tell you that my car is pretty damn low and rides very smooth, yet the car never bottoms out. If I'd had the room I would have done a similar setup in the front as well.
Vince

zbugger
02-09-2005, 01:02 PM
Hey Vince, any chance of hooking up and letting me see the car? I wanna make Dennis jealous.

Conekiller13
02-09-2005, 01:09 PM
I think I would list this specific product in the bling catagory. I don't think it's the "best" system out there and especially not for that kind of money. For 5k You could fit a C-5 IRS with Coil overs. Looking at the rest of that companies catalog I don't see products that look like they've had a lot of race track style R&D. Push rod actuated shocks ae a great thing............usually done to get the shocks out the air flow and clean up the areo on open wheel cars and prototype racers. I noticed that company also sells adjustable upper control arms..........every time You adjust Your camber or caster You change the length of the upper arm and alter Your camber curves and geometry.

Mean 69
02-09-2005, 01:19 PM
Well now, isn't this interesting. I think I know what is going on here. This looks like a bit of a re-engineered TCP rear suspension systems. Those of you who have been following along for several years have no doubt seen the thread on cc-com.

From what I gather, TCP seemed to upset a ton of their distributors and key customers in the past. TCP recently "went under," which basically means they sold the rights of production of their products to Chris Alston Chassisworks. Before this happened, I understand they were doing some business with the re-pop factory that the Shelby folks put together (Unique Performance is the outfit, I don't know all of the ins and outs of this particular business). It would appear that they pee'd them off big time, because nowhere on the UP site/advertising would you see the TCP name mentioned, when CLEARLY the products they were putting on these cars was indeed TCP stuff (including the front coil-over setup).

Don't be so quick to dismiss the notion of a rocker type shock arrangement. In and of itself, it can indeed reduce the unsprung weight, as well as overall weight if the appropriate motion ratios, etc are chosen. The open wheel cars use this primarily as a means to get the suspension stuff out of the wind path, they tuck everything up under the cowlings, etc. Ever seen the inside of a Daytona Prototype? They too use this technique. We have actually been thinking of doing something along these lines for a cool project car. Is it worth it, on a PT car? I don't know, maybe, it is a bit more complex.

In this example, you can see the springing medium, as well as the Watt's if you visit the site, but what about the longitudinal links? The TCP setup uses a Torque Arm, in conjunction with relatively steeply inclined LCA's. Those, in conjunction with the ultra low roll center, well, do the math and you can see that this aspect of the design could use some "help," putting it nicely. Hopefully the folks that re-engineered the basic design recognized the pitfalls, and addressed them. Anyone want to take odds that they didn't?

Mark

MuscleRodz
02-09-2005, 01:51 PM
Thanks for the good info Mark. I had no intention of considering it. It was something I had not seen yet and still way above my head suspension wise. I think I will stick to the 3-link.

Mike

Mean 69
02-09-2005, 04:06 PM
All of the nasties, aside, isn't that thing sexy?! And frankly, there is nothing there that couldn't be corrected to "work," and without too much effort. Yeah, yeah, I am a function over form guy, but it is so cool to see a really well executed design that just *looks* cool. Baby!

M

MoeBawlz
02-09-2005, 04:34 PM
so what might be done to "help" this suspension?

Tig Man
02-09-2005, 05:14 PM
Anyone heard of KEEP IT SIMPLE STUPID!!!! Number 1 rule in Motorsports!! The more complex things are the more trouble your going to have..


Mark

MrQuick
02-09-2005, 05:31 PM
Thank you , I do remember that echoeing in my head...I just wanna at least get to the track... hey Mark any updates on your car. Like to see some (MORE) pictures of it. I heard you were improving on it? thanks, the thread pirate

Mean 69
02-09-2005, 06:37 PM
KISS. No doubt, a really important virtue. Holds true , very much-most-of-the-time. But!

The earliest of cars were equppied with solid axle, leaf sprung ordeals, fore and aft. Heck, they worked really darned fine, 'til this guy named Maurice Olley came along and showed that a steering knuckle, with ball joints, could be a big improvment. That was just the start.

Goodness. Fast cars, in virtually any form, aren't "simple," and I mean absolutely no disrespect, but have you seen so may of the cars out there these days? Computerized EFI, twin turbos, unreal drivetrains, but where is the innovation in the suspension?

Further, I know that you have wrenched on the Riley/Scott T/A cars as you have posted here previously. I'd still love, as well as a buddy of mine who has asked several times of you, to get a copy of the Riley/Scott T/A chassis that you have. It'd be great. You can PM me to keep it off of the thread, if you'd like.

Bill Riley's car won the 24 Hour Race at Daytona two days ago. He didn't use front and rear leaf springs to do so. Of course, they didn't need to run to the 7-11 for beer in the car either.

Mark

MuscleRodz
02-09-2005, 08:21 PM
All of the nasties, aside, isn't that thing sexy?! And frankly, there is nothing there that couldn't be corrected to "work," and without too much effort. Yeah, yeah, I am a function over form guy, but it is so cool to see a really well executed design that just *looks* cool. Baby!

M

I agree it looks cool. The main problem I see as far as fitting it is I don't see any place to get an exaust around the thing.

Mike

dennis68
02-09-2005, 09:31 PM
Exhaust....we don't need no stinking exhaust.

Real cars dump before the axle. :moon:

David Pozzi
02-09-2005, 11:24 PM
I don't see anything bracing that frame front to rear...

I'ts flashy looking and eliminates leaf springs in a pretty compact package.
The lower rear roll center would require a larger rear antiroll bar. The RC would move up and down relative to the cars center of gravity which isn't the best. A car set this way would tend to have more oversteer on corner exit than one with a chassis mounted watts pivot. A lot depends on how much rear squat the car has when you hit the gas. Can't tell if it's a three link or torque arm setup. I see two lower links though.

zbugger
02-09-2005, 11:46 PM
This pic makes it look like a torque arm. Looks a lot like a copy of the TCP stuff.
http://www.uniqueperformanceproducts.com/images/SUBFRAME_1_large.jpg

Mean 69
02-10-2005, 08:02 AM
Yep, that's the one. A clear copy of the TCP deal. Notice the training arms' upward, they used the original mounting locations for the forward leaf eye in the front. This is one of the special cases where the only lateral restraining device is the Watt's, and as such, the roll axis runs parallel to the LCA inclination. Since it is upward, this means roll OVERSTEER, which is basically bad.

The other drawback is the T/A itself. It's short. Outstanding for anti-squat, but not terribly good for reducing the chances of brake hop. Bad #2.

It would have been SO easy to tweak out this design a bit, bummer they didn't do it, it could have been a really sweet little package. As for the price, unless you are going to fabricate your own stuff, it really isn't that bad. That is assuming it comes with the 9" housing (no guts though), shocks/springs, and all other harware. If they followed TCP's lead on the main brackets, it is a really easy to install setup too.

Just my opinion, your mileage may vary.
Mark

MuscleRodz
02-10-2005, 08:20 AM
I just found a thread over at cc.com thats a year or two old where TCP was attempting to defend their products especially this rear set up. Not for the faint of heart. there is like 480 replies! Ouch! I read half of it last night, and although it shows promise, it was never fully developed correctly is what I have understood from the thread. It was also about half the price what Unique is asking as well.

Mike

PAI Racing
02-10-2005, 10:00 AM
Don't know why I am jumping in here... but theory aside, TCP's AIX car did flat-out haul ass.

redss86
02-10-2005, 01:18 PM
It all looks like the TCP stuff. Everything from the suspension, to the subframe connectors. From what I have seen its identical to the TCP stuff.