STALX Supra - The Ultimate Time Attack MKIII

[LordDigital]

It is the time of the year to wake up the beast

First weight reduction ,wanted to do carbon hatch with plexan but never got a chance to buy it so it will be on the list for next year. Removed my Optima redTop ,it was a good battery and served the car well BUT times have changed. 5 years ago the price for a 7lbs battery was nearly $400 and now I got one for $70 thus i reduced the weight of the car with nearly 30lbs for $60 - good deal

Optima Red top 35lbs ,new dryCell battery eBay special 7lbs. Relocated the battery similar to the fastest GroupA supras (not build by Toyota TTA,TRD, or even TTE but by Bemani ):

Retained the Ground Switch to the old location ,I've already developed a quick reactive quick shut off skill did not want to change that:

After all the years of AutoX and Road Racing ,I'm now 100% convinced that the rear sway bar is not needed iff the car has string springs for its weight. It is simply too much of a compromise especially when the power levels are in the 400WHP. I tried it for AutoX last season ,disconnected and connected and I was slower with the bar. Not only that but the Wes arms are really not designed for MA70 and the clunking was
terrible! Bye Bye rear sway ,see you on the supraMania's market soon

 

[spiller]

Interesting that the sway bar made the handling worse. What spring rates are you running? Maybe just a stock rear bar would be better? I drove my car without a rear sway bar for a week and the handling was scary! Also re: the wes arms, are they an improvement over what was there before?

 

[LordDigital]

Interesting that the sway bar made the handling worse. What spring rates are you running? Maybe just a stock rear bar would be better? I drove my car without a rear sway bar for a week and the handling was scary! Also re: the wes arms, are they an improvement over what was there before?

The handling in terms of maximum Gs ,corner speed ,etc was definitely worse after I disconnected the rear Sway ,however the improvement in exit speed was much greater. The net result was that the times without the rear sway bar were better. Front bar is a must and I'm using the strongest available (grey colored bar).

Wes arms are good ,improvement in handling is hardly noticeable - the main benefit is ajsutability. Unfortunately he designed them for his Cresida and they simply can't work on MK3 with rear sway bar. I have a short video in my phone to show you the issue ,will get it on YouTube in a moment.

 

[LordDigital]

Here is the video ,basically the subframe side uniball should've been poly bushing do avoid arm swing when doing weight transfers.

[video=youtube;K45BFDxyERU]http://www.youtube.com/watch?v=K45BFDxyERU[/video]

 

[spiller]

woah! that sucks. I have the full set of his arms at home that i havent had a chance to fit yet but thats disappointing. So what's actually causing the knocking sound, the rod end hitting against the subframe? I can see that the swaybar would mimick what you are doing with your hand but there must be a way to eliminate that knocking sound, and that movement is probably not good for the longevity of the rod ends. Have you spoken to Wes about this?

 

[dslocal]

You may be able to just unscrew the heim joint and replace it with a poly bushing/mount

 

[spiller]

^^^ didnt think of that, but that would work. Wes does make poly ends for them now too.

 

[LordDigital]

^^^ didn’t think of that, but that would work. Wes does make poly ends for them now too.

The Poly rod ends should be then standard on his product ,I will send him PM with a link to this thread to help him improve his product. No wonder why the A1 arms were available in poly only on the subframe end ,otherwise the A1 was much worse design not only because they were prone to failure but also because their adjustability was one end only and required the arm to be removed from the spindle ,who DOES NOT remember this thread ?

http://www.supramania.com/forums/showthread.php?118445-A1-Racing-Arms-Catastrophic-Failure-BeWare

 

[spiller]

I sent wes a PM earlier with a link to your vid just to ask him what he thought. Is it just the control arm that moves around at the subframe end or do the toe and traction arms do the same thing?

EDIT: surely the lower camber arms and the toe arms need fixed bushes at the subframe attachments and not spherical heim joints to prevent the issue you are having and preserve the alignment of the wheel in dynamic situations?

 

[LordDigital]

I sent wes a PM earlier with a link to your vid just to ask him what he thought. Is it just the control arm that moves around at the subframe end or do the toe and traction arms do the same thing?

The rest of my arms are still A1 ,they do rotate but since they are not connected to the sway bar it really is not an issue. BTW now I remember that on one of my runs when I was testing sway connected ,the WES arms were not only making so much clunking but also the power of the impacts was enoguth to propel one of the rubberized counter balances on the rear subframe ,the otehrwise heavy peace took off like a torpedo and ended up hitting a parking lot pole!

 

[spiller]

LD, on a seperate note, ill be in Chicago again in August, just booked my flights this week! Hopefully I can arrange a time with you to catch up and take a look at your car.

 

[wesbeech]

First off the arms were made and designed for the mk3 supra long before the Cressida arms were. We do offer a poly rod end that replaces the heim joint. If you are having this issue send me a pm and I will give you a good discount on the poly rod end for the toe arms to corect the issue.

WES

 

[LordDigital]

First off the arms were made and designed for the mk3 supra long before the Cressida arms were. We do offer a poly rod end that replaces the heim joint. If you are having this issue send me a pm and I will give you a good discount on the poly rod end for the toe arms to corect the issue.

WES

Thanks Wes,

I will PM you if I ever decide to reconnect OEM rear sway and need poly rod ends.

I now see that you have castor/camber adjustable UPC ,which appear to be similar to Group A Type 3 FIA/JAF homologated arms MA70 supra ,great product keep up the good work! If you ever decide to make similar LCA ,I can provide you the pictures of the Group A arms ,the major benefit for our car will be that the front track can be improved with adjustable LCA and a lot of fellow members won't have to use 30 or 40mm spacers that would load the bearings quite a bit...

 

[wesbeech]

Also since your arms we have gone to a much higher quality chrome moly heat treated and Teflon lined heim joint. They last much longer and make much less noise.

WES

 

[LordDigital]

I've spend a lot of time on troubleShooting the tach not working issue ,after 2 dashBoards and 2 ignitors the IGN- wire was apperantly shorted with another connecting wire or god know what ,I tested it and it is not grounded and the condectvity from ignitor connector to the dash was perfect ... what a mistery ,solved it with running a direct IGN- wire:

Also got the car weighted ,OLD school way of course - in my garage with 4:1 multiplers and scales.

Here are the results:

Basically car weight with no driver is 3048 pounds! That is with 1/4 Tank of Fuel ,30lbs of reinforcement on rear Sub ,3000+ SCCA Cage that weights at least 100lbs ,rear hatch that can easily be converted to CF with Lexan to safe another 70+lbs and 1.5JZ which is probably 30lbs heavier than 7m. Goal for next year will be 2900 )

 

[spiller]

thats pretty impressive on the weight but as you said, could easily be lower with some panels. Do you still run the bumper support bars and stuff? Some FRP front fenders and bonnet would help shed a few too.

 

[LordDigital]

thats pretty impressive on the weight but as you said, could easily be lower with some panels. Do you still run the bumper support bars and stuff? Some FRP front fenders and bonnet would help shed a few too.

No bumper supports of course

The truth is that the numbers may be impressive for you and possibly a dozen of forum members here ,but in reality this is still pretty heavy car for time attack build using the MA70 chassis. Compared to the GroupA supras build by TRD ,TTE and TTA (So called Works Cars) it is lighter weight ,BUT compared to the privately ran Supra MA70s in the European Championships build by R.A.S. and Bemani I have a loooooooooong way to go! Their weights reached 2300lbs towards the end of the ERA which for MA70 that is Race Ready (and that does not include drag strips) is like reaching the speed of light! I have tons of information about the private Group A Supras ,including all European Magazines that ever published any details about their builds but I'm still puzzled on as much as 300lbs of weight reduction...

 

[slowmedown]

2300Lbs in a mkiii supra? thats crazy

 

[spiller]

2300 is hard to believe, thats just over 1,000 kgs. I guess not impossible but insane! LD, i agree, 1382kg is still heavy for time attack but I think you could get that to sub 1300kg fairly comfortably without cutting and shutting things. The lexan windows would go a long way to achieving that. I need to get mine on the scales to see what she tips in at. Ive done a total interior strip down (everything gone except dash pad) and lots of other stuff including A/C and heater etc. I dont have a cage though so i'd estimate a number similar to yours, maybe less because I only have a 1JZ.

another question for you regarding your car; are your subframes solid mounted or are you using poly?

 

[dmp316]

wow very well done. I have been to many AutoX down here in Miami and never seen a supra. I am happy to know someone build a Time Attack Supra.