View Full Version : Coilover stuff....
Racetek82
04-21-2003, 07:44 PM
A few things that have come up while working on the rear setup. I found that by positioning the lower shock mount about an inch back, and maybe about 1/2" outboard, I gain tons more clearance for the spring, sleeves,and collars. This will allow the spring to sit lower on the shock, and increase travel. This poses a few issues though. The first being that it will alter the "working lever length" of the suspension arm. This means the force applied by the spring will be placed on a farther point than the stock is, and spring rate will need to be altered. Also, I'm worried about the stock shock mount, and the trailing arm itself, being strong enough to hold up the amount of continuous force that the coilover setup will be putting on the end of the arm. Being that the original spring sits closer into the subframe, and it sits on a fairly beef section of the arm, it's very well supported.
To solve this issue, I have a tentative design to build a support for the underside of the trailing arm. Think of it as an exo-skeleton of sorts for the arm. It will bolt to the underside of the trailing arm, and will extend past the stock shock mount, repositioning the shock as stated above. From the bottom of the support plate, another triangulated support will extend rearward, and meet at the bottom of the new shock mount, offering even more strength. This piece will stiffen the trailing arm, allowing it to resist flex and bending in the center, and play a dual role by placing the shock where it will work the most efficiently. This piece will be part of the rear coilover kit, and may be offered separately. This is pretty much the only way a rear coilover like this will be safe, short of making a new trailing arm from scratch. I could do that, but it definitely won't be cheap.
I also have been thinking about offering a three point rear shock tower bar for use with the coilover setup. It will mount to the shock tops of course, and the lower bars will meet at the center of the trunk floor, between the shock towers. This will help strengthen the shock towers, and absorb some of the upward force from the springs.
Racefiend
04-21-2003, 07:56 PM
Another mounting point you could consider is the ones for the rear seat latches. Make the bar a 5 point in that case and you have that much more support. Just a thought.
An issue with repostitionint the shock, AND having a coilover setup to boot....will that interfere with the wheel, especially those of us who run 17x9 with ~275 tires?
Christian
Racetek82
04-22-2003, 12:15 AM
Another mounting point you could consider is the ones for the rear seat latches. Make the bar a 5 point in that case and you have that much more support. Just a thought.
An issue with repostitionint the shock, AND having a coilover setup to boot....will that interfere with the wheel, especially those of us who run 17x9 with ~275 tires?
Christian
I may use that idea...if it's cost effective to add the two extra mount points. We'll see if it's necessary. As for clearance on the coilovers. I have 16x8.5 Epsilons, with 245 tires, and it clears just fine. Do you have 17x9's Christian? If so, maybe you can come by and test fit it when I do the first prototype. Unless someone wants to donate a rim for me to use as a fitment tool. I'll take some pics of things as I work....if you catch anything I don't, constructive criticism is always welcome.
Racefiend
04-22-2003, 12:15 PM
Well, I have the Braid rims on the way..should be here shortly. If you need a test supra I'd be happy to use mine for test fitting. Let me know how things go.
Christian
Racetek82
04-22-2003, 03:14 PM
sounds good Christian..I'll be in contact with you as things progress. I'm trying to get prototypes done by late may/early june. If all goes well...production will begin before summer is over.
mkii_supra_freak
09-14-2004, 11:42 PM
Did this thread just die?
Whats the progress?
Am in need of some kind of adjustment for the rear. Cantilever coilovers sounded like a winner, what happeneD?
Thanks,
mitch
ksourounis
09-15-2004, 12:38 AM
i have been waiting for that cantilever setup for ever now, and it seems too complicated to happen.
still dreaming though
Racefiend
09-15-2004, 01:50 AM
I think so. I haven't seen Ray post on here in a LONG time. Nor have I seen him on aim. :confused:
SupraRacer36
09-15-2004, 12:30 PM
Heres a link apprently he has a rear coilover setup on a celica gts that works http://www.greenhydrant.com/~drees/auto/celica/coilover.php
SupraFiend
09-15-2004, 04:23 PM
I think a set of these are the best way to go for coilovers in the rear of our mk2s....
http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=HR92-K-X100A02
http://www.turnermotorsport.com/image/suspension/suspension_e30m3_hradjust_compare_lg.jpg
rsdeo
09-15-2004, 04:46 PM
I think a set of these are the best way to go for coilovers in the rear of our mk2s....
http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=HR92-K-X100A02
http://www.turnermotorsport.com/image/suspension/suspension_e30m3_hradjust_compare_lg.jpg
I posted those before, just never had time to purchase and try them.
rsdeo
09-15-2004, 05:07 PM
I would also like to try mounting coil overs where our stock rear spring resides. I have an idea.
williamb82
09-15-2004, 06:09 PM
Heres a link apprently he has a rear coilover setup on a celica gts that works http://www.greenhydrant.com/~drees/auto/celica/coilover.php
that had nothing to do with ray. that site has been around for ages.
william
3000cc MK2
09-16-2004, 01:20 AM
as for reading some import magazines I have encounterd on the new 350Z coilover set-up from greddy and it uses the same identical rear trailing arm set-up on our cars and they use a adjusting collar on the bottom and the spring is on the top... same as the picture above
SupraRacer36
09-16-2004, 05:00 AM
When I siad he I wasnt talking about Ray I was talking about the guy whos site that was
mkii_supra_freak
09-16-2004, 12:23 PM
I like the idea.. "Get hur done!" and get back to us and give us your virdict. I so need Camber adjustment in the rear..Damn ST Springs...
Thanks,
Mitch
SupraFiend
09-16-2004, 05:10 PM
try a spacer in the rear
bbaacchhyy
09-16-2004, 08:07 PM
This is interesting that it has come up again.
I have fitted Koni Yellows on my Mk2, and to do this, I used MA70 rear shocks with a rod end bearing to mount it on the stock lower shock mount.
Here you can see a pic with my 17x8" rims with +6 offset (and with a spacer that will be removed for these rims - spacer was fitted for other rims)
http://img16.exs.cx/img16/633/2004-07-26007.jpg
The MA70 rear shocks have a platform to mount the rear spring, so it should be pretty easy to adapt them to take rear coil over springs without making mounts !!! They can be seen through the wheel in this pic.
http://img82.exs.cx/img82/9706/2004-07-26010.jpg
I'll have to have a look in teh shed over the weekend. Will definitely have to have a good thing about approriate bracing though.
What sort of spring rates would be the best ? I'll do some calcs based on the differeing leverage length for the springs that I have in the standrad position.
Cheers
Michael B
Racefiend
09-17-2004, 04:13 AM
The iffy part about that would be the stress levels on the mounting points of the shock. The bottom of the shock is only held to the arm by the end of that bolt. I doubt it could take the load of the car all on it's own. Most likely it would bend very quickly. A quick fix would be to weld a square frame onto the arm to fit the bottom of the shock. The top is also questionable, being that it's thin cone shaped metal with little bracing. it would work for up/down loads, but be rather weak for side to side loads.
white_mk_2
09-17-2004, 11:29 PM
Here's the solution (sorta), I posted this awhile back. Never contacted these guys at the time and now they're not making stuff anymore :(
The spring stays in the same place so no reinforcement/body mods are neccesary = GOOD.
This is similar to the other posted adjustable perch but for larger diameter springs. These should fit our stock springs, I've taken rough measurements of the Volvo springs for comparison.
http://www.mvpvolvo.com/content/project_images/1986_744TGO_B230FT-18.jpg
http://www.mvpvolvo.com/
white_mk_2
09-17-2004, 11:36 PM
Oh yeah, MVP is located in Portland, Oregon. their phone number is 1-503-892-9405. Someone that lives near them should go over there and see whats up. Find out who machined these for them and whether we can get them made again (a Supra specific version maybe). I'd do it but I'm on the other side of the country and I know there a lot of PacNW peeps on here.
ksourounis
09-20-2004, 12:01 PM
have you actually taken measurements to see if they fit?
this is the exact thing i am trying to do, but our setup is a little differnt.
first, we have much larger diameter springs, so getting smaller diameter
coilover springs may not sit on the control arm unless some kind of lower
perch is welded in place
second, our bump stop comes very far down on to top mounting point of the spring, and it would look like a very short spring would be needed if any drop is desired.
still the easiest and safest method to try. i am going to try some stuff on
my parts car with a prelude kit.
bbaacchhyy
09-20-2004, 06:44 PM
Making an adjustable perch for the std springs is interesting and certainly has advantages over the coilover shock, but the size of the collar and thread needed makes it difficult/expensive due to the spring ID.
I'd be happier probably reinforcing the upper shock mount, making a decent 3 point strut bar and doing it that way, but it my have to wait till after the car is engineered. I'll probably do the fronts then as well. The main reason for doing it this way is the shocks already have the platforms on them :lol:
Any feedback from the Celica GTS conversion with the issue of the body structure ? Anyone ?
mkii_supra_freak
09-20-2004, 08:23 PM
Instead of getting these rear height adjusters made specifically for our application why not get an existing adjuster with a spring that coils down to a smaller size like this.
http://www.c3cars.com/CFJFiles/C3Cars/9214.jpg
Or get a perch like this and look for a spring to match.
Look under the coil over section, bottom of the page.
http://www.hrsprings.com/site/frameproducts.html
This is just a thought, I just want some advice and to press on with our progress in having some chamber adjustments so I can stop eating tires.
white_mk_2
09-21-2004, 12:58 AM
Making an adjustable perch for the std springs is interesting and certainly has advantages over the coilover shock, but the size of the collar and thread needed makes it difficult/expensive due to the spring ID.
Well the MVP adjustable perch is for a full size spring the same size (or nearly) as ours. So it's already been engineered and built. They made versions for 200s and 7/900s, I had measured these awhile back but don't know the measurements offhand. I do remember they were /should be compatible with our spring diameter. I'd like to have rear height adjustment but otherwise I'd go for some kind of spacer to restore ride height.
bbaacchhyy
09-21-2004, 01:52 AM
Well the MVP adjustable perch is for a full size spring the same size (or nearly) as ours. So it's already been engineered and built. They made versions for 200s and 7/900s, I had measured these awhile back but don't know the measurements offhand. I do remember they were /should be compatible with our spring diameter. I'd like to have rear height adjustment but otherwise I'd go for some kind of spacer to restore ride height.
If that is the case, it will be pretty easy to make up a small collar to make up the difference.
Can anyone contact MVP from that side over there ?
I'd be keen to hear a price/availability/details for sure
Cheers
Michael B
ksourounis
09-21-2004, 02:32 PM
well, what springs would we use with this larger
diameter lower collar?
i wanted to do this for cheap, but it looks like a
$180 dollar order of whatever spring rate we
want will get the job done.
i guess we can put that lower collar on the
stock or eibach or st springs, that would
not allow for further lowering of the car.
i want to be able to go from just above stock, to quite a bit lower
lower for autocross, higher for drag racing and street
white_mk_2
09-21-2004, 04:30 PM
well, what springs would we use with this larger
diameter lower collar?
Well the beauty of it is you just use whatever springs you have now :) Just any stock or aftermarket spring. If you want to go lower then just cut the spring down a coil, this would increase the springrate as well and allow you to raise the car back up. I must say though with the ST springs I definitely wouldn't want to go any lower, I actually want to raise the rear a hair.
bbaacchhyy
09-21-2004, 06:41 PM
but it looks like a
$180 dollar order of whatever spring rate we
want will get the job done.
So is that what these collars cost for a pair ? USD $180 ? Does that include the springs, or is it just a pair of threaded collars plus the locking rings ?
Material is ?
Cheers
Michael B
ksourounis
09-21-2004, 10:17 PM
from the tunermotorsports site, it looks like its just the adjusting sleeve
in which case we would need another 100 or so for springs
bbaacchhyy
09-21-2004, 10:59 PM
What is the web address/link so that I can have a perve please ?
Crocket
03-20-2007, 11:09 PM
I hate to bring another old thread back from the dead, but I've been thinking about these rear height adjusters lately, and was wondering if anybody here has actually done it (ksourounis or white_mk_2)?
Sonny
Powered by vBulletin® Version 4.1.9 Copyright © 2012 vBulletin Solutions, Inc. All rights reserved.