February Fastrack

[lateapex911]

what would the ITB weight be, theoretically? I figure it would be in the 2600-2650 range, which under the current cage rules is still 1.50/0.095" - it used to be that you'd go to 0.120" wall at (I think) 2500#.

I'd bet wheel sizes and the lack of a need to change classes due to IT7 is the best reason to not reclass the RX7, and the disappearance of 12A parts I keep hearing about mean its days are likely numbered anyhow.

Yea, the number of cars that have cage issues is unknown.
What IS known is that no RX-7 (legal) has ever run at the top of the ITA world. (And I aint talking local, I'm talking the Rucks and Mosers and the Bettencourts of the ITA world). Actually, MOST guys in their RX-7s wouldn't finish ahead of a decent ITB field AS iS. So adding 300 won'y make it better, LOL

 

[Ron Earp]

Well, much of what you saw is now gone. Also, I spent an entire day at a race prep shop creating a laundry list of things to do to reduce weight and the end result wasn't encouraging. Plus, I've had people with some SERIOUS racing and car building cred practically beg me not to throw any more money at the car, and one of them is a trusted friend who doubles as a valued sponsor..

Hey Chris,

I feel your pain with your trials and tribulations but, you're also a relatively new racer. The yard stick you're comparing to is KVS who's IT cars are some of the best prepped in the country, plus, the man has been driving IT cars for a long time and is consistently a fast driver in any car.

If I recall correctly you're using a take out motor that isn't prepped to maximum IT rules but is still making pretty good power. So, you're going to be down on power for sure compared to a KVS IT team effort. The Canadian builder who specializes in 3.8L V6s is a good guy to talk to but ultimately there are many domestic Ford builders who can make the motor work well. Ignore the folks on the bolt on 3.8L V6 boards, they don't get IT-prep an never will. They'll feel an off-the-shelf header is fabulous but when looked at from an IT perspective with the goal of maximizing area under the curve, port velocity, and scavenging then it isn't a good choice.

Until your Mustang has gone on a rotisserie, been stripped, and put back together with attention paid to everything with respect to weight and choosing the lightest components available then it is hard to know what weight they will get to. And as Dick mentioned on his IT7 build, you'll need to look at every rule and approach it from many angles to take full advantage of what limited prep we have in IT.

Back when I had my Mustang I planned to disassemble the car to the tub, take it locally to have it dipped and stripped to bare metal, and then put it back together. I do agree that a full prep Mustang probably won't make weight with a 175 lbs driver, but I believe that it'll get close enough that it won't matter if one is willing to put in the time and/or money depending on how they approach it. For me that means a lot of work as I don't have the cash to farm the build out.

But, you've got to decide how you want to go with the project. It could be very expensive to say re-design the cage to take advantage of the 2699 lb bar rule in order to save 18 lbs. And buy wheels that weigh 13 lbs each to save 20 lbs. But in the end that is how a top prepped IT car is built.

I still want to build one of these things. Anyone want to buy a Z ITS car?

 

[dickita15]

what would the ITB weight be, theoretically? I figure it would be in the 2600-2650 range, which under the current cage rules is still 1.50/0.095" - it used to be that you'd go to 0.120" wall at (I think) 2500#.

I'd bet wheel sizes and the lack of a need to change classes due to IT7 is the best reason to not reclass the RX7, and the disappearance of 12A parts I keep hearing about mean its days are likely numbered anyhow.

For cars built under the 2007 roll cage rules if the cars spec weight is less that 2380 (2200 + 180) then you can have 1.500 X .095. at the time I poll about 50 cars and just about half were built with .095, the other half had heavier tubes.

I see under the current rules you could weigh as much as 2699 with .095.

But like you said the time has passed

 

[lateapex911]

I see under the current rules you could weigh as much as 2699 with .095.

But like you said the time has passed

yea, the decision on what to do with the RX-7 was made before the new cage rules came to be. So the call was to lower the weight, citing the cage issue, the wheel issue, the IT7 issue, and the Process issue, which, if it fails the car in one class, will fail it in another. The weight wasn't set because the ITAC thought that is the lowest weight the car could achieve, it was set because that's the number the Process spits out.

 

[Chip42]

Yea, the number of cars that have cage issues is unknown.
What IS known is that no RX-7 (legal) has ever run at the top of the ITA world. (And I aint talking local, I'm talking the Rucks and Mosers and the Bettencourts of the ITA world). Actually, MOST guys in their RX-7s wouldn't finish ahead of a decent ITB field AS iS. So adding 300 won'y make it better, LOL

I didn't say it'd be FAIR at that weight. just working backwards from ITA weight. I do MR2s, I get it.

 

[RedMisted]

If I recall correctly you're using a take out motor that isn't prepped to maximum IT rules but is still making pretty good power.

Until your Mustang has gone on a rotisserie, been stripped, and put back together with attention paid to everything with respect to weight and choosing the lightest components available then it is hard to know what weight they will get to.

Back when I had my Mustang I planned to disassemble the car to the tub, take it locally to have it dipped and stripped to bare metal, and then put it back together. I do agree that a full prep Mustang probably won't make weight with a 175 lbs driver, but I believe that it'll get close enough that it won't matter if one is willing to put in the time and/or money.

Three things here to think about:

A. The theoretical IT-optimized HP rating at the front of one of these things is approx. 238. If that is true, given that I have all the peripheral stuff done, then I only have another 8 ponies to gain. Not enough to get me excited for the car's prospects.

B. Granted, the weight thing can't be known until it is done. But you keep talking about stripping the entire car down to bare metal. It has been suggested that, in respect to my car, some of the return on performance is going to be negated because the stripping is going to compromise an already flimsy chassis. Whether that is true or not, I do not know, but it does make some sense.

C. And don't forget that the antiquated Ford sedan platform the car sits on basically limits what you can do with it. Other cars such as the 944s and the 325is were designed more as performance cars using newer and better platform technologies and components.

Even if I'm wrong about the car's potential, and I hope I am, it's still gonna take a killing to make it competitive. That is for sure. This brings up what Dick said before about the sanity/insanity issue. And my philosophy has always been: If I'm going to go completely mad building a car, it's certainly going to be in a category that might earn me a higher return, whatever that return may be.

Not dissing IT as a category, but I agree with Dick that something seems incongruent when you're talking about IT and big dollahs in the same sentence. Just sayin'

 

[JeffYoung]

I am pretty convinced the 3.8 Mustang can be one of the front runners in ITR.

We used 25% gain on that motor because we didn't/don't know much about it. No one has built one to the max in IT trim. My guess is you are leaving a lot more than 8 hp on the table. Do you have a custom header design? Port matching? .5 over compression? Looked at options on rings? Crank scraper? Aftermarket ECU? Tuning? Exhaust tuning?

Stripping the car of sound deadening and undercoating won't affect stiffness. Most of the stiffness in the central area of your chassis comes from the cage, and you can stifen the front if you want with a strut brace. You want to see flimsy, take a look at the frame rails on a Z car.

The only real fundamental design issue with your car is the live rear, and there are things you can do to fix that -- some of them off the shelf. Are you running the stock setup or have you gone to a tri-link and watts or panhard? Have you looked at what you can do with your front struts to eliminate bump steer?

IT has become a place where you can RACE cheaply. But to run up front? It takes dollars and time, and that is true of any class really.

Just a bit of history. I had many of the same feelings you have now when I started with the TR8. After a year or so of racing, I was reasonably fast but still getting killed by top prep/top driven Z cars, 325s (they used to be in ITS) and RX7s. Some of these were turn key cars from Bimmerworld or Speedsource, that guys had stroked $50k checks for.

I too thought even though I Loved the TR (why? why? why?), it had no chance.

But after talking to Ron and others and looking at what I had, I started to spend time on reliability to get seat time and on development.

One thing you say is true. It's not cheap to develop the first of a breed, and you are doing that. I feel your pain on it. You could have bought a 325 ready to go if you wanted (still can....).

But all I can tell you is that, at least from where I'm sitting, that car looks like it can be very competitive, and your driving/prep lvel seems to be improving EVERY time out. You've picked up what, 3-4 seconds at VIR alone in the two visits there?

Hang in there. The work to get near the front is overwhelming, but it's worth it when you do.

 

[Ron Earp]

A. The theoretical IT-optimized HP rating at the front of one of these things is approx. 238. If that is true, given that I have all the peripheral stuff done, then I only have another 8 ponies to gain. Not enough to get me excited for the car's prospects.

Well regardless of the max gain you know that you aren't there yet as there is a lot you can still do and it is going to account for much more than 8 ponies.

• 0.040" over
• Bore the block with a torque plate. It WILL produce more power
• 0.5 compression hike
• Investigate that valve job
• Absolutely perfect valve geometry
• Stock cam that is perfectly matched to the specs. You might have to have this ground depending on how stockers check out
• Perfect port matching
• Properly tuned header. Anything off the shelf will have primaries that are too large in ID. Merge collectors. Proper length from collector to merge, then proper length/diameter of pipe to blend 2 into 1. Side exist or dump at axle, but dyno time will tell which one is best. Lot of power in the exhaust, and, a lot of time / money. Jeff has about $2.5k in his exhaust, and that is doing a lot of it himself. It has paid off.
• Open ECU - use a standalone ECU as there is area under the curve to be had. The car has all the good signal inputs needed for this.
• Windage control and crank scraper. Power to be had here. Probably have to design an oil pan since I doubt there are any off the shelf units
• Light pressure plate. Probably have to have it made with a ally pressure plate with steel insert.
• Pulleys are free, make sure you're under driving everything and pay
• Parts bin blueprint/balance that engine. Send the pistons/rods you don't use back and return them.
• Watch your intake. There is one year that is preferable.
• Pay attention to your air intake and pickup in the engine compartment

I understand where you're coming from with respect to the time and money with development. But, until all that development is done you'll never know the potential of the car.

With respect to (b), that isn't going to harm the chassis at all. What it will do is lose a bit of paint/deadening weight off the car, but more importantly it forces you to pull the car apart, and put it back together, installing only the legal parts needed for IT.

And with (c), suspension development - there is a LOT that can be done here. Live axle cars get such breaks in the rules that I think it can be an advantage. You can do tri links or panhard bars, and a sedan can race very well with these. Our tracks are pretty smooth.

It takes time / money to develop an IT car to the max. This is true for ANY IT car, not just your Mustang, and it has been true for many many years. And, I will say your work won't ever be "finished". I'm still developing my Z. This year is exhaust system number three or four, plus springs, and other tuning. Got to keep up with the Jonses'!

 

[Bill Miller]

yea, the decision on what to do with the RX-7 was made before the new cage rules came to be. So the call was to lower the weight, citing the cage issue, the wheel issue, the IT7 issue, and the Process issue, which, if it fails the car in one class, will fail it in another. The weight wasn't set because the ITAC thought that is the lowest weight the car could achieve, it was set because that's the number the Process spits out.

Jake,

With all due respect, the wheel 'issue' is a red herring. Plenty of cars have gone from A to B, and all of those folks had to get new wheels. And IIRC, you were one of the ones that felt that people would happily buy new wheels if it meant that they could be in a class where they felt like they stood a chance of being competitive.

Dick,

While IT7 may be a good indicator that the system failed the first generation RX7, I think there was actually a positive side to it. Kirk's probably better w/ the dates / timeline than I am, but I know that the whole IT7 issue was what got me thinking about developing an objective way to class cars, and was the genesis of what Kirk later dubbed the 'Miller Ratio'. The discussions that followed on this board were what eventually lead us to The Process. I don't think that there's anyone that would disagree that that was one of the biggest steps forward IT has ever seen.

Chris,

That was my issue when the NB was initially classed, that you couldn't run the stock (16x6.5) wheels because ITC had a max wheel width of 6".

Cool deal for the AW11 MR2 folks. Maybe that's an indication that 1.3 power factor for the DOHC 16v cars in B & C 'deal' is over. Maybe it's also an indication that they'll fix other inconsistencies like:

Rabbit GTI: 90*1.25*17+50(close-ratio gearbox) = 1962.5, not 2080.
Scirocco II 8v: 90*1.25*17+50(ditto) = 1962.5, not 2130
Golf (Mk II): 103*1.25*17+50(ditto) = 2239, not 2280
Suzuki Swift GTi: 100*1.25*17 = 2125, not 1895

 

[RedMisted]

I am pretty convinced the 3.8 Mustang can be one of the front runners in ITR.

Much of what you and Ron mentioned has already been done, things like an UD pulley, ECU, panhard, etc.

As for the expected engine gain, it would seem true that there's more on tap than a mere 8 hp. But I'm no engine expert, so I take a conservative tack and follow what the theories speculate. After all, they're in place for a good reason, were arrived at by people with more knowledge than I, and represent a good place to begin with power performance assessments.

I guess what everything comes down to remains to be seen. Everybody has an opinion, and while I appreciate all the encouragement, I'm waiting to see what the engine build is going to do for my car. Yes, I already have an engine waiting in reserve, to be built sometime later in the year. (I decided some time ago to do the engine regardless of the car's other issues.)

Depending on what the ensuing on-track gains show, I'll ultimately decide then and there what the next step should be, and to what extent. It's the most sensible thing for me to do.

 

[JLawton]

Three things here to think about:

A. The theoretical IT-optimized HP rating at the front of one of these things is approx. 238. If that is true, given that I have all the peripheral stuff done, then I only have another 8 ponies to gain. Not enough to get me excited for the car's prospects.

B. Granted, the weight thing can't be known until it is done. But you keep talking about stripping the entire car down to bare metal. It has been suggested that, in respect to my car, some of the return on performance is going to be negated because the stripping is going to compromise an already flimsy chassis. Whether that is true or not, I do not know, but it does make some sense.

C. And don't forget that the antiquated Ford sedan platform the car sits on basically limits what you can do with it. Other cars such as the 944s and the 325is were designed more as performance cars using newer and better platform technologies and components.

Even if I'm wrong about the car's potential, and I hope I am, it's still gonna take a killing to make it competitive. That is for sure. This brings up what Dick said before about the sanity/insanity issue. And my philosophy has always been: If I'm going to go completely mad building a car, it's certainly going to be in a category that might earn me a higher return, whatever that return may be.

Not dissing IT as a category, but I agree with Dick that something seems incongruent when you're talking about IT and big dollahs in the same sentence. Just sayin'

No car is going to be competitive without tons of money and effort. There really isn't any car out there that you can throw on some bolt-ons and expect to win. I took a already built 10/10ths car and over the past four years have put about $12K more in developement.

Again, warts and all..........

 

[Andy Bettencourt]

No car is going to be competitive without tons of money and effort. There really isn't any car out there that you can throw on some bolt-ons and expect to win. I took a already built 10/10ths car and over the past four years have put about $12K more in developement.

Again, warts and all..........

And I used Jeff as an example with a customer the other day that it' soooo much more than car development. He can speak to this better but he REALLY focused on a few tracks and the data from some quick cars and made a really nice jump in laptimes. All from a driver who has been racing for over a decade, lots of cars, lots of diciplines.

It never ends...and that is what can be fun with it.

 

[RedMisted]

And I used Jeff as an example with a customer the other day that it' soooo much more than car development. He can speak to this better but he REALLY focused on a few tracks and the data from some quick cars and made a really nice jump in laptimes. All from a driver who has been racing for over a decade, lots of cars, lots of diciplines.

It never ends...and that is what can be fun with it.

And that may be one of my problems. Anyone who knows me knows that I like to race all over the place. I'll go all the way from VIR to WGI to Gingerman, plus the places in between. I've basically abandoned my home tracks of Nelson and Mid-Ohio because the familiarity was killing me. (Same turns, same competition, same weekends, same beer, etc. etc.) And now plans to possibly hit Road America and Road Atlanta in '11.

Good at everything, but a master of nothing...

Maybe I should stop with the wanderlust and instead take the time/money saved and put it into car development. But... the driving and racing is what it's all about for most of us. I guess the car development thing will have to just creep along as time/cash allow...

 

[Rabbit07]

I like to say, "Spend your money on tires and seat time. In that order."

Good luck getting an SN95 Mustang to 2700 though, not likely going to happen.

 

[gran racing]

And that may be one of my problems.

Absolutely not. I think that will help you in the long run and not just be a one or two track wonder as some term it. Once a driver becomes good, they should be able to go to a new track and be pretty much at the top of their game within a test day or really less. Really good drivers only take a few laps. Unfortunately I'm not there...yet.

 

[tnord]

Absolutely not. I think that will help you in the long run and not just be a one or two track wonder as some term it. Once a driver becomes good, they should be able to go to a new track and be pretty much at the top of their game within a test day or really less. Really good drivers only take a few laps. Unfortunately I'm not there...yet.

i totally agree with this.

the only way you might suffer that i can think of traveling around to different tracks is not having your gearing right depending on where you're at.

 

[JeffYoung]

Drive a car with torque and don't worry about it.

Seriously, at least around here, I only have one or two places where I'm maxed out in 3rd and don't want to shift -- one at Roebling and one at CMP. If I play with tire sizes I can work around it.

 

[Rabbit07]

With a Mustang final drives are abundant. If you are handy and do the home work with shims you can change them at the track in about an hour if you are off. I used to do that with my ITB Mustang all the time. It's one of the advantages to the Mustang.

 

[GKR_17]

Drive a car with torque and don't worry about it.

Seriously, at least around here, I only have one or two places where I'm maxed out in 3rd and don't want to shift -- one at Roebling and one at CMP. If I play with tire sizes I can work around it.

No kidding - out of curiosity, I ran your TR8 data through my gear program, and it made virtually no difference to change the final drive at any of the SE tracks.

 

[Andy Bettencourt]

Absolutely not. I think that will help you in the long run and not just be a one or two track wonder as some term it. Once a driver becomes good, they should be able to go to a new track and be pretty much at the top of their game within a test day or really less. Really good drivers only take a few laps. Unfortunately I'm not there...yet.

But you are missing the point. Unless you have a GREAT development program, travelling to many different tracks that you haven't run before will probably maximize FUN at the expense of DEVELOPMENT. You need to be at a track that you can run consistantly before you can even think about finding the last X% (you determine your goals) of your driving and/or finding the last X% of your suspension program.

Development is what we are talking about here.