Who has tracked their MKIII?

Dustin

New Member
Nov 25, 2005
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Cloverdale, BC
Yes yes I know Supras are supposed to be straight-line cars you race little boys on the highway with but since I hate drag racing, I'm curious about who here has taken their MKIII to a track day, autox, hillclimb... even rally

I'd love to know a general idea of what kind of setup you're using/used while on the track. Suspension, tires, brakes and a rough idea of RWHP

I've already progressed a little bit in learning the limits of the car and hopefully if all goes well financially for me next year I should be able to put a good chunk of autox time in, possibly some track time and maybe a hillclimb next year.

Currently, my car is basically all stock. Engine wise, it has some piece of shit exhaust that I'd barely count as aftermarket (3" megan racing DP w/ flex section, 2.25" crush bend to a cat, to a glasspack, to a muffler and a stock elbow), ARP head studs and a manual boost controller @ just below fuel cut. Stock suspension, stock brakes. Currently I've dynoed at 223hp/261tq

My plan is simple for this car:

Tires and possibly wheels--but if I upgrade wheels, I'm going to keep them as 16" and only want to upgrade to reduce unsprung mass (Thinking Rota Slipstreams in a 16x8, only around 14lbs each). Tires are going to be stock 225/50R16 in and around the $200 USD each range

Brakes. This is going to be first before anything else, as I've basically destroyed whatever brakes the P.O. put in. Just regular NAPA rotors and performance pads. KVR, Axxis.. not sure yet

Exhaust: I need this badly to unlock the power I'm missing and decrease the damn spoolup time.... BIC DDP, 3" test pipe, 3" back.

Chassis: I'm trying to figure something out right now for bracing the body and keeping it rigid... I think I have an idea for the area behind the front seats and to the rear hatch. Fairly important for this car

And that's really all I want to do.

Oh and a second question since I'm already talking about it. I've been searching and reading past threads like mad for the last day or so and I've seen a bunch of people talking about how a 3" exhaust turbo-back with the BIC DDP will cause you to spool past 12 PSI on stock boost. Is this really true? I kind of doubt it but I wanted to make sure first. I really dont want to be hitting fuel cut all the time in 4th gear

Thanks
 
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ToyoHabu

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Jun 25, 2005
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NO! supras are not good strait line race cars. The drag strip was the last place the designers envisioned them to be. A GT car is not at home on the drag strip. You do not put uneven a-arm supension up front and multi link suspension in the rear on a drag car. Though the supras have found success there doesnt change much. I haven’t really done anything but autocross, would like to take it to a track day at Barber or road Atlanta sometime. Friend of mine in town has gone to a Driving school event at little Talladega (Sport Bike road track near Talladega) someone in an RX7 (LT1 or LS1 powered) actually set their brakes on fire when they forgot to do cool down laps. http://www.tgprace.com/. My car was a 86.5 NA when I started Autox. My only mod was to go with Eibach springs and Bilstien shocks. The problem with that was it put me out of "stock" class strait into "street prepared" and now with my 1jz engine I am in the "street modified" category. The cost to be competitive goes up with each class. So get a copy of the rules in the series you plan to compete in and decide what class you comfortable with and make mods consistent with that class if any. If you are in US here is link to the SCCA solo rules SCCA Rules
 

Dustin

New Member
Nov 25, 2005
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Cloverdale, BC
With the mods I have in mind, I should be in the new SST class assigned for cars with wheel/tire upgrades and other minor things. I may end up just being in stock though if I dont get upsized wheels (which I plan not to)

I really doubt it will be competitive in an autox situation due to the high weight, but the car really shines in high speed corners. Typically I dont care about classing in autox anyway, so long as my lap times are in line with what I was expecting

When I autocrossed my MR2, I was completely outclassed being in CSP with prepped Miatas and what not, but I was more concerned about times relative to other mild cars like mine was set up :D
 

Adjuster

Supramania Contributor
I think if your having fun, that's what counts in Auto X. (Times are nice, but really, there are lighter cars out there with less power running faster lap times, and that's just life.)

Race those same cars on the street, and you shame them. :)

You can't just drive your car to 9/10th's of it's ability on the street, so real power does matter in the real world. (Tough to be smooth and save your energy on the street when you have ruts, bumps and stoplights to deal with...)

Not that I'm a street racer by any means... LOL
 

mkIIIman089

Supramania Contributor
Mar 30, 2005
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Ohio
Dustin said:
Oh and a second question since I'm already talking about it. I've been searching and reading past threads like mad for the last day or so and I've seen a bunch of people talking about how a 3" exhaust turbo-back with the BIC DDP will cause you to spool past 12 PSI on stock boost. Is this really true? I kind of doubt it but I wanted to make sure first. I really dont want to be hitting fuel cut all the time in 4th gear
I can say that it is definitly true from my own experience, and I do not even have a divorced downpipe. During the summer fuel cut was more rare, but now that its winter, 4th gear every time hits fuel cut. My Blitz TT is telling me I'm at .87 peak boost, for reference, and I have no type of boost controlling device what-so-ever.
 

Dustin

New Member
Nov 25, 2005
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Cloverdale, BC
mkIIIman089 said:
I can say that it is definitly true from my own experience, and I do not even have a divorced downpipe. During the summer fuel cut was more rare, but now that its winter, 4th gear every time hits fuel cut. My Blitz TT is telling me I'm at .87 peak boost, for reference, and I have no type of boost controlling device what-so-ever.

That's kind of saddening as I really dont want to invest in the Lexus AFm or 550 injectors and am really just looking for a faster spoolup and just overall smoother power. I suppose I could always just go with a 3" DP and a smaller diameter exhaust... Maybe 2.5" from cat-back. I'd like to keep boost below factory fuel cut anyhow
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Weight being so high running a Mk3 on the track would require some sort of brake upgrade as fade is going to be an issue.
(bare minimum flush the fluid and replace to remove all of the water)
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Dustin: When I built the BBK for my car I flushed the system with metholated spirits until it came out clear then swapped out the Master Cylinder, Flex lines and Callipers reflushed it all with Metho again till it ran clear.

I then ran some Motul 5.1 through it again till it came out clear.

Brakes are now brilliant :).
 

csnow

Matthew 6:33
Apr 5, 2005
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Palm Bay, FL
Seems like the Supra is not the car you should be using. Too heavy and long. Sell it and get something more inline for your needs.
 

Dustin

New Member
Nov 25, 2005
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Cloverdale, BC
csnow said:
Seems like the Supra is not the car you should be using. Too heavy and long. Sell it and get something more inline for your needs.

I've already had a lightweight, short wheelbase car (MR2) and I bought the Supra specifically to try and learn how a heavy car behaves/handles and how to drive a powerful car fast

The car in stock form with shitty tires is already very grippy and always impresses me :D
 

Asterix

Lurker of Power
Mar 31, 2005
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Vienna, VA
Get rid of the rubber in the suspension. That right there makes for a very different car. Then, get the Suspension Techniques sway bars and some way better springs and shocks. The suspension on these cars is truely excellent, but has been hamstrung by the marketing people at Toyota.

If you're willing to make engine changes that bump you into a more modified class, you should upgrade the suspension as you can.

Asterix
 

ma71supraturbo

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Mar 30, 2005
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www.geocities.com
Dustin said:
Tires and possibly wheels--but if I upgrade wheels, I'm going to keep them as 16" and only want to upgrade to reduce unsprung mass (Thinking Rota Slipstreams in a 16x8, only around 14lbs each). Tires are going to be stock 225/50R16 in and around the $200 USD each range
Stick with stock wheels and put the wheel $$ toward other mods or for the purchase of 17" wheels later. Buy the best tires you can

Brakes. This is going to be first before anything else, as I've basically destroyed whatever brakes the P.O. put in. Just regular NAPA rotors and performance pads. KVR, Axxis.. not sure yet
Use stock or slotted rotors until you can get a big brake kit. You will be much more likely to crack crossdrilled rotors so avoid them. For pads, Porterfield, Endless, and KVR make excellent products. A "race" pad will be louder, dust more, and wear out the rotors more quickly. It will also require a few warm-up laps before it works well. The high-performance street pads will work as well as stock when cold and hold up to heat much better. But they will fade under hard use. Motul RBF is the fluid I use, although it should be flushed before each track event (assuming you do track events less often than once a month) as it doesn't "keep" as well as a more street-oriented fluid. Stainless steel brake lines help with pedal feel and also replace 20-year old rubber which will increase your confidence at 120mph... If you're feeling inventive, remove the front fog lights and use dryer hose to duct in air to the brakes. This will help with fade tremendously, but a MK3 on stock brakes is going to be a 3-lap car. If you're doing a track day, just brake a little earlier and give up a few tenths at the end of fast straightaways...

Exhaust: I need this badly to unlock the power I'm missing and decrease the damn spoolup time.... BIC DDP, 3" test pipe, 3" back.
I agree. To save some money, check out the 935 and Cooleeze "DIY" cat-back exhausts. They use mandrel-bent 3" piping and you can weld your own muffler on...

Chassis: I'm trying to figure something out right now for bracing the body and keeping it rigid... I think I have an idea for the area behind the front seats and to the rear hatch. Fairly important for this car
Do you have a targa? I wouldn't bother with strut tower bars -- at least initially. A double-wishbone car does not rely so heavily on the upper strut mount for support. If anything, a triangulated strut tower bar would help keep things rigid. A simple and effect rear brace is the MDC motorsports harness bar. It ties together the upper front seat-belt mounts and the lower rear seat-belt mounts and gives the car more rigidity. Plus is allows you to use racing harnesses safely


Some things you left out:

Suspension. Go with nice coilovers with stiff springs (16/10-20/12). Save up if you have to -- they make a world of difference in making the heavy MK3 much more manageable at speed. Also check all of your bushings. My MK3 had 60,000 miles when I got it and thankfully the bushings were still decent. Unfortunately, my recently acquired MK2 had shot bushings and were the first thing I replaced. Poly bushings are reasonably priced for the initial purchase, but if you can't install them yourself plan on spending another $350-$800 in labor charges. But they will make the car noticably more "solid" and you can get more consistant alignments.

Differential. Yours may be shot, it may be alright. A quick test is to be at the base of a steep hill. Turn right up the hill in first gear and floor the accelerator. If the LSD is worn, the right rear tire will spin and the car won't make a ton of progress. It will also track pretty straight. If the LSD is good, the car will fishtail a bit and it'll be obvious both rear wheels are getting power.

Seat: The stock MK3 seat is actually pretty darn good, but if you are going to be serious a nice bucket seat will keep you firmly positioned giving you more precise control of the pedals



I'm not sure what year MR2 you have, but it took about 3 years and a few thousand dollars in suspension experiments before my MK3 was as fast in the corners as my 91 MR2 (below 30mph). Above 30mph, the Supra is pretty even until ~60mph -- where the Supra really shines.


Long term plans:

17" wheels and a Big Brake kit. If you don't have the wheels, you can't use the brakes. The purchase then becomes fairly significant, but 17" tires also give you a few more tire options. Unfortunately tire prices also go up too...
 

hot dayam mk3

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Oct 17, 2005
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i auto x and go to speed trial events with my supra all the time. suspension would be the #1 thing to work on the supra. prolly would get coilovers and tanabe sustec or whiteline swaybars since st swaybars are still weak. if you cant afford the coilovers. buy bilstein struts used on the jza70 and some nice linear springs with a good spring rate. i would buy swift springs. next would be a good brake setup and tires. you dont need to run big brake kits but run some nice brake fluids, some stainless steel braided lines, and some nice pads like endless and you will be fine. also the tires i run are bridgestone potenza re-01
 

Dustin

New Member
Nov 25, 2005
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Cloverdale, BC
With regards to mods, I've been meaning to change my approach with modifying this car. My MR2 was a 1985 and I basically had everything short of coilovers (which in a short wheelbase car like that are murder) and it was a great car, a LOT of fun

It also took a lot of concentration to drive. The way I had it set up was very twitchy and very fun. But this Supra is already on another level. The approach to cornering fast is much different, and it's really a completely different experience

With the MR2 I basically did everything all at once in the span of a month... springs, struts, bushings, sway bars, strut bracing, wheels, tires, motor mounts, shifter throw, shifter linkage, shifter housing, brakes, agressive alignment... It was really not the greatest approach, because it changed the handling dynamics too much that I had to re-learn the car and I didnt really focus on the problem areas

Suspension will be great for the Supra but I think I'm gonna go in this order for upgrades:

Brakes

Tires (stock size)

Change alignment depending on feel of the car

Exhaust (really, the main reason for this is just that the exhaust on it is a piece of shit and I just hate the idea that the last owner's cheap crap is stealing performance from me)

Bracing (I have some ideas for tying in the body between the floor and roof, side to side and front to back. Not really concerned too much about strut tower bars, but instead the rest of the body. The body is pretty flexy right now and I can feel it on bad surface roads)

Sway bars (depending on feel after tires and bracing)

It's fairly hard to get an idea of what the car needs right now anyway, as the tires are shit--and really, the most important part of any handling package is tires. Once that's taken care of, I can put some seat time in the car and get an idea of what it needs and take care of it then

Just bolting on parts is never as effective as learning the car and improving what you feel needs improved! :) I would also like to try and focus on chassis improvements, just because I really am clueless about chassis tuning, and I'd like to learn as much as I can. What better way than an old, big, heavy car to test on?

Oh, and my differential is working great ;) I love having LSD
 

Ckanderson

Supramania Contributor
Apr 1, 1983
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thats pretty good... although i would place sway bars ABOVE exhaust...

the sway bars make a HUGE difference in the feel and controlability of the car.

I recently ordered big brakes (precision brakes 14x1.25 with 6 piston calipers) wont fit under a 17 inch rim (at least not my old ones) i cant WAIT to get my car running again to try them out..

I have faded my stock brakes trying to set up a profec a boost controler... it is a VERY easy thing to do, even with slotted and cross drilled rotors..
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Surely is it's brilliant!

I struggled with shocks bars springs trying to tune out the understeer and was fighting a losing battle until I picked up the diff!

They aren't the strongest centre and will explode on hard launches with sticky tires but I'll never see either of these conditions so aren't too concerned.