That's impressive! 8 hours is no joke. Did you have any issues with heat / brake fade ect? What do you think is the weakest part of your car right now?
Track Car Setup - Advice Needed!
- Thread starter dahughes
- Start date
Considering none of our group had ever raced before we were happy just finishing the race. As an added bonus we even beat a team! This car was purchased for lemons/chump car racing but in this race we were going against spec miata's, an MR2 and a quick sentra. Considering the fact we spend only $3k for the car in race trim we were pleased with our finish. The track has 13 turns but good drivers only use the brakes about 4-5 times per lap. I'm betting we used the brakes a lot more as they heated up and started to fade about half way into the race. By the end of the race there wasn't anything left. Every driver got about 60 laps and showed improvement between lap one and lap sixty. We are planning to get some additional seat time with a track instructor before the next race in early April.
So assuming our diving skills continue to improve and we learn to save our tires, brakes and fuel I would say the car's greatest weakness would be suspension. The previous owner cut the springs about 1.5" and ran KYB shocks in order to comply with Lemons car rules. We aren't ready to drop $1k on a set of coil overs but are looking at a set of H&R race springs. The car did come with two sets of 245/50/16 tires (toyo proxy 4) that we will run until they are gone. No reason to spend money on tires when we are still learning and have extra's in the garage.
Additional changes before the April race based on feedback here includes:
1) Mounting existing tires on a set of RX-7 wheels. Should save about 10 lbs per corner.
2) Bleeding the brakes and replacing the fluid with Castro (DOT 5 I believe)
3) Replace brakes with EPC yellows
4) Install H&R springs
5) Install poly bushings front and rear
6) Have alignment done as suggested by several folks
7) Have the engine tuned. The car runs strong above about 2500 rpm's but at lower rpm's and at idol it runs rough and almost wants to die. Previous owner said he built it to run like this (rich) at low RPM but strong on the top. As we have limited turbo experience we would like to have someone look at it and assist with a tune. We want to maximize reliability and economy. In 8 hour races we think this is more important then flat out power.
8) Get a two way radio set up. The car has push to talk now but we don't have the right radio's or helmet mic's.
9) Possibly install hood louvers to help under hood temps.
10) Get some practice laps in with a track instructor.
Looks like a long list but shouldn't be terribly expensive and is a good reason to spend some time with the guys working on a race car. How great is that!
So assuming our diving skills continue to improve and we learn to save our tires, brakes and fuel I would say the car's greatest weakness would be suspension. The previous owner cut the springs about 1.5" and ran KYB shocks in order to comply with Lemons car rules. We aren't ready to drop $1k on a set of coil overs but are looking at a set of H&R race springs. The car did come with two sets of 245/50/16 tires (toyo proxy 4) that we will run until they are gone. No reason to spend money on tires when we are still learning and have extra's in the garage.
Additional changes before the April race based on feedback here includes:
1) Mounting existing tires on a set of RX-7 wheels. Should save about 10 lbs per corner.
2) Bleeding the brakes and replacing the fluid with Castro (DOT 5 I believe)
3) Replace brakes with EPC yellows
4) Install H&R springs
5) Install poly bushings front and rear
6) Have alignment done as suggested by several folks
7) Have the engine tuned. The car runs strong above about 2500 rpm's but at lower rpm's and at idol it runs rough and almost wants to die. Previous owner said he built it to run like this (rich) at low RPM but strong on the top. As we have limited turbo experience we would like to have someone look at it and assist with a tune. We want to maximize reliability and economy. In 8 hour races we think this is more important then flat out power.
8) Get a two way radio set up. The car has push to talk now but we don't have the right radio's or helmet mic's.
9) Possibly install hood louvers to help under hood temps.
10) Get some practice laps in with a track instructor.
Looks like a long list but shouldn't be terribly expensive and is a good reason to spend some time with the guys working on a race car. How great is that!
May I suggest: Castrol SRF at $75.00 a liter; it will get me and the Supra through two seasons. It is a good value; it has one of the highest wet boiling points on the market.
I also recommend the Porterfield R4-1 carbon-Kevlar brake pads over most the others, as I've tried most of the others and for the money, I find the Porterfield's the best al-round pad for our stock rotor and caliper set-up. They have very good bedding in results, come up to ideal temps quickly even on cooler days, have a moderately high coefficient of friction, are easy to modulate, have ceramic on backing plate and are rotor friendly. Downside is they dust horribly! Van
I also recommend the Porterfield R4-1 carbon-Kevlar brake pads over most the others, as I've tried most of the others and for the money, I find the Porterfield's the best al-round pad for our stock rotor and caliper set-up. They have very good bedding in results, come up to ideal temps quickly even on cooler days, have a moderately high coefficient of friction, are easy to modulate, have ceramic on backing plate and are rotor friendly. Downside is they dust horribly! Van
I agree, don't use simple DOT 5 as it's silicone based and is not recommended for ABS systems (or high vibration). DOT 5.1 is made like DOT 3 and DOT 4 so it's fine.
So, different car and different chassis, we're talking about an MA70 chassis not the Toms GT500 running a 3gs motor making 480BHP, with an unknown chassis set-up. Let's make sure we help this team on a budget.scottiedawg66;1899953 said:how is chassis stiffness easily measured?
Unless there is a way to get data, rather than make claims based on empirical evidence of which the source and context of information is unknown, this conversation is going no where and we continue to derail this thread as I stupidly respond to people telling me what I can and cannot feel.
If the teams that raced Supras at the highest level (JGTC) were using strut tower bars on their cars wouldn't you at least try them considering the low cost and ease of installation?
if it is good enough for the Tom's JGTC supra (dual wishbone) its good enough for me.
With that said; the Bemani team was successful and used these bars as shown in the picture. I'd suspect that those
are there more for safety than stiffness?
Van;1900552 said:
This shot of Bemani engine compartment represents their DTM configuration ,with a VO cage of 88 made of AL CUMG1 (weight of 22KG). The additional reinforcement bar from the front sub-frame would've been rendered illegal for many FIA events ,but was ok for DTM. Cage was designed for stiffens and UBER-LOW-weight with only minimum required safety ,Bemani had no choice but to cut their weight down as much as possible to have a chance against the Germans ,they could not get the car down to the minimum 1040KG ,but 1050KG or 2300lb was still pretty damn good
Here is a pic of their R&D for the MA70 chassis stiffness ,no wonder why their cars were FASTER than any other MA70 build known to motorposrts history ,including TOMS/TRD/TTE and other factory "creations"
josbeat;1915954 said:
Jose ,Aluminium cages were forbidden after the end of the Group A when FIA changed Apendix J of their regulations. In 1988 when the car was reBuild for DTM , Toyota had already homologated a few Aluminum cages (AL CUMG1) ,I've just checked and the cage that I see in the MA70 N/A homologation book is also in the book for the Turbo (just look at the Option Variant from Feb 1 1988 ,08-06VO ) ,when looking at this book further I see that MOST of the cages homologated by Toyota for MA70 Turbo were in fact SCM430 Steel ,but there were 2 or 3 that were aluminum.
When it is true that the aluminum cages were not nearly as strong as stell (again according to the official JAF/FIA book from Toyota => 3.0mm AL CUMG1 had elastic limit of 22kg/m^2 ,strength of 38 kg/mm^2 when the SCM430 at half the thickness had strength of 70kg/mm^2) ,we have to keep in mind that the FIA rules of the 1.7 era (1988 and later) mandated that the minimum weight of the turbo MA70 had to be 3100lbs and the DTM rules allowed N/A Supras to be as low as 2270lbs!
Coincidentally ,after 4 years of 3 cars race program in the European circuit championships , Bemani continued to race the MA70 chassis for many more years in Swiss Touringcar Champ with 3S-GTE engine ,hillClimbs with 7m-GTE engine and to the best of my knowledge they never had a single fatality ,when the TRD/TTT Factory race with the SCM430 cages had IIRC at least one fatality at SPA...