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FASTMETABOLISM 01-29-12 12:36 AM

Rotaries and road racing
 
How many of you guys have had good luck with road racing the good old rotary? Anything to be aware of? How well does the motor hold up?
I'm considering buying an fd to road race, so I would like some insight from those who actually do it.

finger lock 01-29-12 01:49 AM

The FD is an excellent platform for road racing and the 13BREW can be very reliable if properly setup and managed. The issues with the motor typically revolve around managing heat.

The answers to your questions will depend greatly on the level of modifications (motor and chassis) are you considering?

Guy

FASTMETABOLISM 01-29-12 09:38 AM

I've been considering buying an fd(turbo rotary) to track. Probably at stock power levels for a while.
I'm aware heat kills rotaries, and fuel management is a weaker point with these cars already.

D Walker 01-29-12 10:44 AM

the issue with an FD with the turbo motor is you cant race it in anything but NASA, and I wont get into my opinions about NASA.

A 1st or 2nd generation car can and have been run in multiple different classes and can be very competitive. There is also an extreme amount of information out there about racing them, and a lot f development work has been done.

The RX-8 is an excellent racing platform with plenty of development behind it and you can occasionally find ready to go cars out there for very reasonable pricing. The advantage to the RX8 is it can be raced in an even wider variety of classes, all the way up to professional racing. In World Challenge we are using the Renesis motors, some Club racing classes allow the use of backdated P-Port race motors.

As far as reliability- I prefer rotaries as race engines, they tend to just last longer and have fewer issues overall. I think as a street car engine a rotary requires more attention and care than the average end user wants to deal with, but as a race engine they require very little comparative maintenance and produce excellent power for their weight.

FASTMETABOLISM 01-29-12 11:11 AM

It's tough to say. Idl how serious I would take it, as in competing, but im more into it for the enjoyment of being on a track and having some fun. Although you do bring up some good points. Cause if I do plan to compete in the future, which is possible, I may be very limited to my options.

Brent Dalton 01-29-12 11:24 AM

For a fun track day car(or more if you are a grassroots racer), it's hard to beat the rotary FD, and you can make them very reliable as the others above have mentioned. Not sure what series D. Walker is referring to above, but Guy(fingerlock) won SFR SCCA ITE in his rotary FD this year. Fritz has been wearing them out on track for years as well. I've done my fair share to, but switched engines a couple of years ago(due to wanting more torque for my class, not because of reliability issues). Ptrhahn on here as well. Tons of other guys on here that are either not active or guys in the past that have moved on to other things.

D Walker 01-29-12 11:25 AM

If your into it for the enjoyment, go to the track, experience what you like, maybe beg/borrow/rent a ride in various cars, and then figure out what you want BEFORE you spend the money. I do not recommend a newcomer start with a street car and try and build a racecar, as that can sour real fast. There are tons of cars started that are never ever going to be finished, and lots of drivers that give up because they spend more time working on the car than driving it. If you want a track car, go get a track car and run it.

Brent- I believe ITE is a regional only class? I do not really keep up with club racing so please feel free to correct me if I am wrong. When I think of racing, I think of being able to do more than make laps at the local tracks, which might be part of the confusion.

Brent Dalton 01-29-12 11:35 AM

Yes, regional class. I don't know many people that compete at a National level that are asking these types of questions. :) I agree that making laps is not racing. I was making an assumption based on his posts above that he is looking at doing track days.

D Walker 01-29-12 11:40 AM

Also, I should add that my Pikes peak car that we have run a few track events with uses a S6 (FD) turbo motor and is decently reliable.
A couple of years ago i looked at building an "all out" FD race car, but there is not a National class for it, so at best it could run regionally, made it a really tough call. We went with the RX-8, and the cars work great.
I am more than aware there are guys tooling around the track in RX-7's and some are really quick, but again, track day vs racing is a tough one in an FD.

Brent Dalton 01-29-12 11:49 AM

When you are saying "No National Class", you are referring to SCCA?

RX-8's are great cars and I have a good bit of experience in them. A large majority of my track buddies are RX-8 guys. Majority of them have owned and tracked their RX-8's since 2004. Some track days, some TT, some W2W. With the exception of one or two of them, they've all been through several engines. Majority of them were covered by the Mazda warranty though so it's hard to argue with that(obviously not replaced under warranty on the race cars). Still great cars, but IMO they don't hold a candle to the FD in the fun department. If racing in a SCCA National class is your perogative though, I can see why you would go that route. Otherwise, NASA has plenty of places for it ranging from PTC to SU and everything inbetween. NARRA as well.

D Walker 01-29-12 02:36 PM

Well, my interest is in Pro racing, I really dont follow Club racing at all, so not as familiar anymore. However we do occasionally run the car in Club racing (SCCA and NASA). And yes I was speaking of the SCCA National classing.

I have not replaced a single engine in my RX-8 due to failure, but I do tend to refresh them fairly often. The engine in the #07 car went all 5 WC races we ran last season, no issues and is still going strong. I believe it is the same engine the car won the 9hr Road Atlanta enduro and several Club races with, along with many test days.

Track day cars are not really what I do, or even have interest in, so please be aware that all comments are made with the idea you eventually want to be able to race with good competition. People often enquire as to the best method to get into racing, and I have watched all the comments about doing HPDE and so on, but if you want to RACE, and possibly get somewhere with it, I do not believe that is a good path. What I typically recommend is to get involved not with a street car, but with a low-cost Formula car such as Formula Vee, Formula First, or Formula F. This allows you to learn to race a car that is designed to be a race car. You skip all the time spend asking questions about modifying this or tuning that, and just concentrate on driving the car. A decent Formula car setup is $15k or less, the community is very supportive, and best of all, its a race car from the word go.While driving an open-wheeler you get to learn about suspension and setup and other mechanical aspects of the car that directly relate to driving the damned thing fast. You might also be able to get into an older Formula Mazda, which is a very sturdy and well-developed platform.

Next step IMHO is a proper tintop racecar. I tend to gravitate towards Production or GT type cars rather than the more common "Spec" cars like S944/SE30/SMiata, etc. because tub cars cost a lot of money to rebuild when you bend them, and when you are involved in "tight" racing, you are at a much greater risk of being involved in someone elses stupidity. Now, the masses will argue for the cheap entry cost of these classes etc., but the truth is that these cars are crap and they are slow and that is not very fun over the long term. Also, Spec classes indirectly encourage cheating and that becomes aggravating as well. Keeping to the Production or GT car theme, and rotary power, I personally would look into a tube frame 13B powered GT or GTLite RX7 or RX-8. In fact, we might be building up a tube frame RX-8 for GT in the near future.

Again, I realize I am speaking to car racing and not trackday fun, but that is what I know.

finger lock 01-29-12 08:03 PM

I think for the original poster there is very good information discussed here. Just for informations sake, the production based FD can run as Brent mentioned in SCCA ITE, and other regional catch-all classes. I have petitioned SCCA to class the FD into the National STO class where it is now allowed. That said, in STO the FD can either run the stock twin turbos or any turbo with a 44 mm inlet restrictor (either at 2750 lbs). I personally don't want to deal with an inlet restrictor and feel that I wouldn't be very competitive so I'm sticking to regional classes. Should I find a bag of money somewhere, I'd like to try a tube-framed GT-3 rotary.

Also, I whole heartedly agree with the progression that Don suggests.

Guy

D Walker 01-29-12 08:43 PM

I was not aware the FD was classed in STO, thanks for that!

A tube car may have a slightly higher cost of entry than a tub car, but the running and repair cost will tend to be less usually. The way I usually explain it is you look at a tube car as something you will drive for many years and when you sell it it is typically worth a decent amount.

FASTMETABOLISM 01-29-12 10:22 PM

Walker,
I completely understand, and agree with what you are saying about jumping into a track car. I dd a boosted ls1 camaro, and though I would love to track it, it's a heavy pig with a lot of mass to move around. I'm looking for something more light, nimble, and just as fun. It would still be a street car, and I do plan to keep the mods to a minimum besides suspension work, becuase my camaros the go fast car. Lol. But I think an fd would be a great experience for me to start in, and progress in for a good while. Even to just go out and have fun. Which is what I really want.
I do agree, there is a lot of useful info here, and I appreciate the input guys.

mustanghammer 01-29-12 11:06 PM

You could also run an FD in STU with a single turbo. SCCA Super Touring classes allow corporate engine swaps so you would not have to run the original engine.

Brent Dalton 01-30-12 07:21 AM


Originally Posted by D Walker (Post 10957462)
Well, my interest is in Pro racing, I really dont follow Club racing at all, so not as familiar anymore. However we do occasionally run the car in Club racing (SCCA and NASA). And yes I was speaking of the SCCA National classing.

I have not replaced a single engine in my RX-8 due to failure, but I do tend to refresh them fairly often. The engine in the #07 car went all 5 WC races we ran last season, no issues and is still going strong. I believe it is the same engine the car won the 9hr Road Atlanta enduro and several Club races with, along with many test days.

Track day cars are not really what I do, or even have interest in, so please be aware that all comments are made with the idea you eventually want to be able to race with good competition. People often enquire as to the best method to get into racing, and I have watched all the comments about doing HPDE and so on, but if you want to RACE, and possibly get somewhere with it, I do not believe that is a good path. What I typically recommend is to get involved not with a street car, but with a low-cost Formula car such as Formula Vee, Formula First, or Formula F. This allows you to learn to race a car that is designed to be a race car. You skip all the time spend asking questions about modifying this or tuning that, and just concentrate on driving the car. A decent Formula car setup is $15k or less, the community is very supportive, and best of all, its a race car from the word go.While driving an open-wheeler you get to learn about suspension and setup and other mechanical aspects of the car that directly relate to driving the damned thing fast. You might also be able to get into an older Formula Mazda, which is a very sturdy and well-developed platform.

Next step IMHO is a proper tintop racecar. I tend to gravitate towards Production or GT type cars rather than the more common "Spec" cars like S944/SE30/SMiata, etc. because tub cars cost a lot of money to rebuild when you bend them, and when you are involved in "tight" racing, you are at a much greater risk of being involved in someone elses stupidity. Now, the masses will argue for the cheap entry cost of these classes etc., but the truth is that these cars are crap and they are slow and that is not very fun over the long term. Also, Spec classes indirectly encourage cheating and that becomes aggravating as well. Keeping to the Production or GT car theme, and rotary power, I personally would look into a tube frame 13B powered GT or GTLite RX7 or RX-8. In fact, we might be building up a tube frame RX-8 for GT in the near future.

Again, I realize I am speaking to car racing and not trackday fun, but that is what I know.

Understand all. I think we are all a little envious of you and your WC team. You are living alot of our dreams of being a pro race car driver :). My point though is he is not asking about pro racing, and probably doesn't have a pro race team budget to refresh his engine often, etc... I was giving him an opinion from a wannabe driver hack :) Who knows though, he may have a pile of mountain of money ready to drop in something and jump right into racing.

Interesting you mention S944/SE30/SM being slow. I'd argue the same about the RX-8 w/ renesis. Everything is relative though.

D Walker 01-30-12 09:40 AM

Here at HPR a really good S944/E30/MX5 lap time is around 2:05, the RX-8 runs sub-2 minute times depending on tires. For some reason we always get grouped in the "lightning" group when we run with NASA, and its just not as much fun.

I am not a driver anymore, just a team owner.

It doesnt really take a pile of money to run a real race car, and in my experience its usually less cost than running a street car out on the track. Back when I started I ran an MG Midget prod car, and I know I payed less to build and run that car than many of my friends who were running in SS or even IT.

I have seen a lot of people waste a ton of money in racing over the years, and really try and keep people from repeating the cycle. All it does is to sour otherwise enthusiastic drivers on the sport.

Cheers,
Don

RockLobster 01-30-12 04:28 PM

Interesting thread. I always like reading Don's insight. (Met him at NASA national championships last year).

From my mostly outside perspective I always wondered how some teams (yours, and speedsource) had such good luck with the renesis motors while others had such terrible luck, many others but there are known extensive examples with a few pro teams. Is it driver? The engine build? The tuning? What keeps /kept those things together for you and speedsource? No need to get into protected build details but a general idea would satisfy my curiosity.

D Walker 01-30-12 05:43 PM

I personally think a lot of it has to do with the tuning. Speedsource had Racing Beat develop the ECU "Race" Flash for them and it works. Makes good power and the motors seem to last. Unlike most of the "tuners" otu there, Jim had Mazda and Speedsource bankrolling his R&D and could do pretty much whatever he wanted with the ecu's, blow as many engines as he needed to, etc. to come up with something, and they did a bang-up job IMHO. I called him first of the season begging for even 5 more hp, to see if he had left anything on the table, a degree of timing here, maybe a little fat there, but nope, he swore to me that I had all there is to get out of this engine configuration. I believed him. Never bothered with the AP because it has pretty much proven to me to cause more issues than it fixes.

I know that other competitors were working with tuners that barely if at all understood rotaries and the how and why of tuning them for track use. When these cars were put together we seriously thought about developing an AEM ECU for the platform but tabled the idea after driving the cars, but might restart the program in the near future based on how well our new motors like the existing ECU's.

As far as my engine builds, they are like any other- clean all the parts, use new parts where you should (springs especially) dont replace what you dont have to (side seals etc.) and use good parts (Goopy Apex seals, decent O-ring kits, etc.) then assemble it paying attention to what your doing and how it goes together. All of my housings look brand new, even after a lot of race use. I have not balanced a motor yet, but the new motors for this season are going to be. With the Goopy Apex Seals we have almost instant compression numbers where we want them, and after the first 30 minute session they are good to go. Have not tried ceramic apex seals, and do not plan to. I try never to use new rotor or stationary gear bearings, but if it must be done we then need to run that motor for at least a few test weekends before we try and race it. There is a process to "swage" the bearings to size after pressing them in that we are going to try, but have not tried it yet.

I think the driver will have some effect on how long the motor lasts, but I keep going back to the tuning.

I will tell you, point blank and no BS, the motor that is STILL in the number 07 car that ran St Pete, Miller, and Mid-Ohio is the exact same engine that came in the car when I got it, and that engine I truly believe has done the 9 hours of Road Atlanta, at least 4 NASA Club race weekends (won each time out) and possibly one or two ARRC's (class winner) and its STILL GOING.That motor came out of a low mile salvage car. Yeap, thats right, 225whp on a junkyard motor and its run 5 Pro races and many Club races. Reliability? Maybe.
The #08 caris the test bed and has had motors we built and tested in it, and both cars are getting 2012 WC spec engines in the next couple of weeks.

FASTMETABOLISM 02-01-12 11:44 AM

That's nothing short of impressive on a pull out stock motor. And no, sadly I don't have a pile of money to blow. But enough to get me into a decent fd.
I guess that answers my reliabilty question. Hahaha

j9fd3s 02-01-12 12:36 PM


Originally Posted by Brent Dalton (Post 10958313)
Interesting you mention S944/SE30/SM being slow. I'd argue the same about the RX-8 w/ renesis. Everything is relative though.

we have run up against an Rx8 in both the 25 hour (factory cars) and USTCC, and the Rx8 does quite well. i've never timed them, but they are a couple seconds quicker than us, so maybe 2:02-2:03 at thunderhill?

we did run SE30, and those ARE slow. 145rwhp/2750lbs isn't fast, its like 2:10's at thunderhill. it is competitive though, and there are a ton of them, so its good racing.

TrentO 02-05-12 06:32 PM

We run a turbo FC and a turbo FD up here in Canada. I've run two seasons of Time Attack and 2 three day race weekends at the Edmonton Indy on the same engine. My car is pretty far gone in the modification department, but reliability comes from controlling the heat and providing enough fuel. We've found the stock twins to be too restrictive for road racing as they contribute too much to the heat load. A good GT35R (or comparable) turbo kit + a fuel system + big rad + big intercooler + good oil coolers makes for a reliable 400 rwhp road course car. Check out my FC here: www.rxracing.com

-Trent

mschiap 02-07-12 12:32 PM

We race an 83 RX7 with a 12A in LeMon / Chumpcar endurance racing. The engine that was in the car when I bought it for $500 is still in there, going strong after:

100,000+ street miles (broken odometer) and
80+ hours of RACING across multiple endurance racing events.

No engine problems, so far. Running stock radiator and beehive oil cooler. You could do a lifetime of track days before you put as many hours of track time on a car.


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