JZA70 Time Attack Track and Street

[spiller]

Hey guys,

taking a different route with my JZA70, which has been off the road for almost 12 months with a mysterious electrical issue while I looked for a new auto electrician and tuner. I now have a Mitsubishi Lancer Evo 5 which is my daily and since I rarely drive the Supra, I decided I would focus on building it for track use in local time attack and club sprint events.

This is how it looked when i drove it last...

In the past 12 months I have had quite a lot of time to ponder which path I want to take with this car. Since ownership my main focus has been on getting it to turn corners and stop as well as possible before worrying about power. As a result, I am currently still running the stock twin turbos. I was using an Autronic SM4 ECU with which it made 340rwhp at around 17psi with tonnes of mid-range.

I have now decide to do the wiring all over again and will be using a Haltech PS2000 ECU, Haltech HP6 ingitor and Haltech Racepak logger dash to tell me all of the vitals as well as record lap times and other useful data

I am going to be running the car on Michelin Porsche cup racing slicks and I have a room full of other parts that need to go on the car still but current braking and suspension mods stand at:

HSD HR coilovers
Whiteline adjustable sway bars front and rear
BIC performance adjustable sway bar end links
Enegery suspension polyurethane front lower control arm bushes
Arizona Performance Wilwood 4 pot 13 inch brakes front with Performance Friction pads


Sitting in storage waiting to go on the car once I get it back from the workshop:

Evo Brembo rear calipers and Sti rotors for rear brake upgrade
Beech performance rear traction, camber, toe arms
Beech performance front upper camber arms
Solid front and rear subframe bushes (still pondering about whether or not to fit these)

Before sending the car off to the tuner, I stipped out as much of the interior as possible. All thats in there is a dash with nothing behind/under it except the steering column, the front door cards and a driver's seat.

Dry ice was handy in stripping the sound deadening...

Good news is after sitting in my folks driveway for 11 months, the car was finally towed off 4 days ago to commence wiring, followed by tuning along with a few other bits and pieces.

When i get it back I will be fitting the remainder of braking and suspension components before a wheel alignment, bolting the slicks on and making a return to the track!

A custom full roll cage (probably bolt in to retain street use in-case I ever want to sell the car) hopefully in the near future too. Will update as I go along!

 

[kakanator]

Nice build looks like it is going to be fun track car.

 

[josbeat]

hi!
but it still have the stock heavy seat belts!!! jjejeje

 

[josbeat]

what size are the front slicks because I used before a set of those from Porsche and the front was 240-620-18.... too small

 

[spiller]

hi!
but it still have the stock heavy seat belts!!! jjejeje

Haha there are still in there in the pics but I will be pulling them out when i put my harness in!

The front slicks are 250/64/18 from the front of a porsche cup race car but I am going to see if the 270/68/18 fits on the front also (sidewall is too high though I think).

 

[spiller]

what size are the front slicks because I used before a set of those from Porsche and the front was 240-620-18.... too small

the older porsche cup cars ran the 240/620, the 2011 spec onwards now run the 250/64 which should be ok.

 

[LordDigital]

the older porsche cup cars ran the 240/620, the 2011 spec onwards now run the 250/64 which should be ok.

'

Is this the "French Special" - Michelin Slicks?

Good luck with the Build !

p.s. when are you coming to Chicago?

 

[spiller]

'

Is this the "French Special" - Michelin Slicks?

Good luck with the Build !

p.s. when are you coming to Chicago?

Correct it is the michelin slick - people seem to rave about them and others talk of them falling off the cliff terribly after 40% use. They were cheap however (I have 10 tyres here that I paid less than 650 for) so they're really just for a bit of fun before I can work out if I can justify brand new semi slicks but that is unlikely unless I actually compete in competition where slicks are banned!

I was actually just in Chicago for 10 days last week, sorry I didn't have a chance to catch up with you mate, we had barely a minute spare between planning our wedding and seeing family and old friends, it was exhausting, not much of a vacation although I am making it up ATM with 9 days in South Beach Miami .

And, I go home to a running supra for the first time in over 12 months because my tuner emailed me yesterday to tell me he had it on the dyno

 

[josbeat]

any news??

 

[spiller]

I called the tune shop a few days ago and he said he is having an issue with a misfire that they cant diagnose. very frustrating because this has been the same underlying issue with this car for the past 18 months and this time I have had it completely re-wired but the issue persists. I have a lot more faith in this workshop than the last one though and he assured me he will diagnose and fix the problem, but he has been very busy competing in world time attack and there is a bit of a back log at the moment. I am quite happy for it to take a few more weeks though because I dont have any space at my house to store the car at the moment haha.

I do have all of the components here for the STi rotor and brembo caliper brake upgrade for the rear though and will fit that when i get it back! then hopefully fit the rest of the suspension arms and then out to the track!!

 

[1jz-Rolla]

Fingers crossed for you mate, so close!

What brand of rotors did you get for the rear? I've just picked up some Evo calipers but yet to order the rest.....


Cheers
Phil

 

[spiller]

Ended up going with RDA slotted rotors for the rear @ around 300 bucks IIRC. I looked around for ages but those were the cheapest I could find that weren't ridiculous quality. Non slotted was substantially cheaper in RDA too, maybe 80 bucks or so but a machine shop would probably charge that much to swap two rotors.

When I add up the cost of the calipers + rebuild, rotors, pads and lines its not really a cheap upgrade . Guys in the states just walk into their local NAPA and pick up $80 rotors but.

 

[1jz-Rolla]

Yeah there's no such thing as a cheap (good) brake conversions over here hey, damn lucky americans and their cheap parts!

I can't find an RDA catalogue online, and I know there's minor differences between the later model STi rotors, do you have the part number somewhere please?

Can't wait to see some pics/vid when you get back to the track.

 

[spiller]

I dont have a part number sorry mate but when I called they said 2004-2008 is all the same for RDA. They just drill two stud patterns. I remember you saying something about different rotor hat heights though but from what the guys told me there was only one part no. I went through Car Parts Plus here in Adelaide which were the cheapest in the country. Phone no. is (08) 8326 0377. Wouldnt hurt to give them a call and clarify and even ask for a price on shipping to ACT.

Let me know how you go...

 

[1jz-Rolla]

Yeah I think the shorter hat-height only came in on the models after 2008 though. Will be interesting to see when you fit them up, if you need any washers/spacers under the caliper mounting points to align the disc perfectly, let us know

Cheers for the info and contacts.

Phil

 

[spiller]

Yeah I think the shorter hat-height only came in on the models after 2008 though. Will be interesting to see when you fit them up, if you need any washers/spacers under the caliper mounting points to align the disc perfectly, let us know

Cheers for the info and contacts.

Phil

No worries, I will take a few pics when i do the instal and throw them up here and/or toymods. Chris reckons it needs a 2mm washer to space the caliper further outboard so ill start with that.

 

[LordDigital]

I called the tune shop a few days ago and he said he is having an issue with a misfire that they cant diagnose. very frustrating because this has been the same underlying issue with this car for the past 18 months and this time I have had it completely re-wired but the issue persists. I have a lot more faith in this workshop than the last one though and he assured me he will diagnose and fix the problem, but he has been very busy competing in world time attack and there is a bit of a back log at the moment. I am quite happy for it to take a few more weeks though because I dont have any space at my house to store the car at the moment haha.

I do have all of the components here for the STi rotor and brembo caliper brake upgrade for the rear though and will fit that when i get it back! then hopefully fit the rest of the suspension arms and then out to the track!!

Lol ,what is with the missFire issue? Can't be that difficult to diagnose...

Keep in mind that the STi caliper is class2 ,not the best choice for competition (better than MA70 stock tough)

 

[spiller]

yeah tell me about it! There are only so many things you can eliminate to get to the crux of a problem and I thought id eliminated just about all of them already haha.

When you say "class 2" Alex, what do you refer to? For instance, the wilwood caliper I have on the front, I know its not a monobloc (nor is the brembo on the rear) but interested to hear more. What brakes are you using on your car mate?

cheers

 

[LordDigital]

yeah tell me about it! There are only so many things you can eliminate to get to the crux of a problem and I thought id eliminated just about all of them already haha.

When you say "class 2" Alex, what do you refer to? For instance, the wilwood caliper I have on the front, I know its not a monobloc (nor is the brembo on the rear) but interested to hear more. What brakes are you using on your car mate?

cheers

There is an unofficial classification of calipers ,EVO/STi/350Z calipers are all Class2 which means that their heat tolerance is worse than a class1 rotor. For the rear that really is not that important ,unless of course you plan on going mad and removing ABS ,installing brake bias valve in other words using the full potential of the rear brakes. For the front that does make difference ,I still have my JDK front BBK in a box with wilwood Superlite 4 pot calipers and I can tell you the difference between them and the Brembo F50 (aka gran turismo) is HUGE.

My setup for the front is Stillen BBK (yes the previous owner purchased it from Sound Performance for the retail which was $3500 in 2003) ,the F50 calipers are so good IIRC tuners used them as an upgrade for McLaren F1... Rear brakes kit came from Dr Jonez car ,old school stuff ... MKIV twin turbo caliper with I believe Jake Reed mounting hardware.

When it comes to brakes ,always remember that SupraGuru is able to compete with his MA70 in NASA on all stock calipers and brakes ,with $100 rotors from a local auto store - not saying that this is bad ,but it requires your constant attention to brake usage...

 

[spiller]

ok, so the brembo F50 is a significantly better caliper than the wilwood superlite 4? this is what I thought and probably why the prices are so different. In regards to my setup, ABS has been removed and I probably will add a proportioning valve in the future if I have issues with the bias. TBH though im not overly concerned as I am not racing and will not likely be doing sessions greater than 15 mins at a time. My local circuit is extremely harsh on brakes, but as you said, since they are the rears, they should be ok.


On an updated note, I got another call from my tuner today. It was good news and bad news. The good news is he is 95% sure he has fixed the issue. The bad news is it was a very simple fix (in the end after hours of searching). So simple that he is quite sure there was no need to re-wire everything and go to a different ECU. The previous fuckwit (the one who convinced me to sell my autronic and that putting a haltech on would fix all of my issues) wired up the coils back to front so the polarity was reversed. He also used the wrong ignition loom - the loom was designed for a CDI except the ignitor was a standard module unit. Consequently the spark was 20-30x less than normal.

What this means? Ive wasted thousands of dollars and over 12 months on the ideas of some useless individual who could care less about wasting customer monies. I could get angry but hindsight is a wonderful thing. I am going to leave the car there for another 2 weeks and then bring it home and drive it for a month or so.

Other things to note: my powersteering is leaking a little, the car has developed the usual 1JZ valve stem oil seal leakage (probably from sitting for so long without lubrication) but this is not too detrimental. The water temps were going up to 105 deg C on the dyno which worries me a little but I think that could be due to the shitty chinese radiator that the previous owner put on there.

What are normal operating water and oil temps for a 1JZ operating under heavy load??