motor for a race car...

wastintime · 04-14-2008, 08:28 AM

I'm trying to see how realistic my dream of keeping a Porsche motor in a race car might be... building a car with a friend, fellow-pro driver, and former driver of the AMS evo... so our choices are a porsche flat-6, we'd do a subie, but they have too many oiling issues for our tastes, or we get a huge break on parts from AMS... so we could do an evo motor.

How cheap, realistically do you think you could build a 500hp 911 motor, either NA or turbo, although if it's a turbo it'd have to be a TT, or buy a crate motor? Anyone know the price of the 997T motors?

Thanks

kenikh · 04-14-2008, 09:41 AM

What kind of car is it going in? The only 500HP motors I have seen fora 911 are twin turbo. The 993 turbos have been known to go that high. Same with the water cooled turbos.

wastintime · 04-14-2008, 09:47 AM

basically a street legal tube frame LMP car, but closed cockpit... Mid engined, 3k lbs of downforce at 150mph minimum...

Basically if I've gotta get rid of my 911, I'd like to keep it's replacement having the heart of a Porsche. It could easily be done on a turbo, but again, cost is my main concern sticking with a Porsche motor.

kenikh · 04-14-2008, 09:49 AM

I hate to say it, but a Vette motor is your best bet. Cheap, reliable and powerful. Big aftermarket, too.

wastintime · 04-14-2008, 10:23 AM

yeah, that's what we're trying to avoid for a couple of reasons including weight and that everyone does it... I just don't want to run the EVO motor because I hate putting an inline 4 in something as cool as this.

Our biggest hurdle right now is manhole covers... but we think we're going to have a race suspension and an air suspension to raise the car and kill downforce on streets

Porschekid962 · Porschekid962's Garage

DONT run an evo motor! They do not like being mounted inline, trust me I know this, we are running evo IX motors in a Lola F3 car and it isnt happy. If you are going to to Porsche and turbo I would strongly suggest one of the newer water cooled motors, perhaps start with a gt3r/rs/rsr motor and turbo it. Or you could just by a Daytona Prototype motor and plug it in.

wastintime · 04-14-2008, 06:20 PM

Well, the GT3RSR motor would obviously be ideal... lol, but I can't afford it. This really is a budget job, the only reason I can afford it is we're building it ourselves for fun. I was thinking about a 996 or 997 turbo motor. Don't worry, lol, I'll do the Vette motor before I do the EVO... I'm just not a huge fan of them. The problem is Jon's had a ton of success with them and was the principal driver of the AMS evo for years, so that's what he wants to do. My thing is if I'm going to spend the money and build a truly NEAT race car... it's gonna have a neat motor or it's not worth it, lol, and if I'm getting rid of my 911 to do it... I'd like to have a Porsche powerplant.

I'm curious though, what problems do they have being mounted inline?

JV911SYDNEY · JV911SYDNEY's Garage

whats the budget? you could easily spend $30k + on a 911 (930) turbo

i'll probably get banned for this but how about a mazda 13b turbo (or 20b) ?

Quote:

Originally Posted by wastintime

I'm curious though, what problems do they have being mounted inline?

+1 ?

rs911t · 04-14-2008, 07:56 PM

I might be wrong, but "This really is a budget job" and "500hp Porsche engine" is oxymoronic ...

Aurel · Aurel's Garage

Maybe this thread could give you some ideas: TT with a $500 4 barrel carburetor:

Alot of work but worth it.

Aurel

eimkeith · 04-16-2008, 06:02 AM

turbo 968 motor. easy.

wastintime · 04-17-2008, 06:24 AM

Yes, I could easily spend $30k on a 911 motor, lol, and I'm not going to because it's basically 50% of our budget for the entire car. Otherwise the GT3 motor would be a no brainer. The only reason this project is going to work is because we can literally do all of the work ourselves, we're literally building the car from the frame up.

Now... the 13b idea isn't terrible, I love running those in MSRs or Formula cars...

Jeff Alton · 04-17-2008, 09:31 PM

I was at my dyno tuner on friday where a single turbo 13b was putting 630 to the wheels................

By the way, this thread is useless without pics of the car/chassis that it is going in.......

Cheers

wastintime · 04-18-2008, 04:16 AM

My only problem with the 13b is the gas mileage... My brother's damn RX-8 got 12.8 mpg on the Highway!!! I mean, granted this is a bada$$ race car, but... the whole point is I want something where a cop is going to pull me over just to see if it's even legal, but I can still drive whenever I want to.

Plus, I'm not sure the 13b will mate to a G50, whereas the LS7, Evo, etc... will

thinking of something that looks llike this: as I said, the downforce is a must.

JayG · 04-18-2008, 07:14 PM

Quote:

Originally Posted by wastintime

My only problem with the 13b is the gas mileage... My brother's damn RX-8 got 12.8 mpg on the Highway!!! I mean, granted this is a bada$$ race car, but... the whole point is I want something where a cop is going to pull me over just to see if it's even legal, but I can still drive whenever I want to.

Plus, I'm not sure the 13b will mate to a G50, whereas the LS7, Evo, etc... will

My 13b gets good mileage 20+ with the Haltech. Kennedy Engineering adapter with a 75 915 tranny. Revs to 10.5 but I never take it that high. Quick little F(*$@R.

330hp

Videos:

http://youtube.com/watch?v=5H1rgjlR1Ao
http://youtube.com/watch?v=pUEcTQF4vtY

Do it.

People can say they sound awful all they want. Most people hear it and freak out. "OMG what in that thing?!?! Sounds crazy!"

"Turbo 13b"

"Rotaries sound like bumble bees."

"After I say something they do"

People can be purists, people can be uptight but just bust their ass and let the times speak for themselves.

Porschekid962 · Porschekid962's Garage

The problems with mounting them inline has to do with the oiling system when run with a dry sump. The oil pressures are all over the place and it has almost nothing to do with lateral g loading or longitudinal g loading, plus mitsubishi specs a huge operating range for oil pressure anyway. Plus why dump a little cast iron 4 banger in there that weighs more than a flat 6? If you are going budget I think the motor to have would be a subaru turbo motor. The rotary engines are great but have no grunt whatsoever and you have to spin then to heaven and back and they have a pretty narrow powerband. Someone mentioned Haltech, I would stay away from it. Pretty much a low on the totem pole feature box with top end pricing, there is so much more out there that is better these days.

I will say though, the evo motor cars have been running all weekend without problem racking up the laps here at the track, they just dont sound racey enough ha.

JayG · 04-20-2008, 05:59 AM

Quote:

Originally Posted by Porschekid962

The problems with mounting them inline has to do with the oiling system when run with a dry sump. The oil pressures are all over the place and it has almost nothing to do with lateral g loading or longitudinal g loading, plus mitsubishi specs a huge operating range for oil pressure anyway. Plus why dump a little cast iron 4 banger in there that weighs more than a flat 6? If you are going budget I think the motor to have would be a subaru turbo motor. The rotary engines are great but have no grunt whatsoever and you have to spin then to heaven and back and they have a pretty narrow powerband. Someone mentioned Haltech, I would stay away from it. Pretty much a low on the totem pole feature box with top end pricing, there is so much more out there that is better these days.

I will say though, the evo motor cars have been running all weekend without problem racking up the laps here at the track, they just dont sound racey enough ha.

I mentioned Haltech, I have it on the 13b. My powerband is from 3000 to 7000 but revs to 10.5. He could spring for AEM but if hes on budget, Haltech is still better than MegaSquirt IMO. The motor makes amazing hp but the torque is lower. Much higher than an NA Porsche but compartively lower. With the lightweight of the car though it is really hard to tell you don't have a lot of torque.

Porschekid962 · Porschekid962's Garage

If I understand you right you are saying that a rotary makes higher tq or makes tq higher than a flat six motor? If it is the former I think you are mistaken, if it is the latter than who cares. Low end tq wins race but this is somewhat of a streetcar am I right? A mazda rotary will bolt up to a porsche transmission if you have to proper adapter plate, take a look at a formula mazda car, 13b rotary mated to a vw bus transmission that has been pimped out by hewland and star cars. No problem there. To be honest I would rather run my motor with a dizzy and carb than Megasquirt or Haltech. Unless you can spring for a competent system (Motec, Autronic, Bosch, DTA Fast, Pectel, McLaren Electronics, EFI Technology and many others) My preference goes up with the listing by the way, Motec is old school by todays standards, most people just use the loggers and dashes but leave the engine control to something better.

As for running with Haltech, how is your cold start? Hot start, part throttle mixing, decel fueling, enleanment and enrichment? I could care less about WOT its the in betwixt that wins the prize and from what I have seen and driven first hand Haltech loses by a lot.

Try and find yourself an Autronic SM4 ecu, one of the most capable ecu's out there for the price, probably the best bang for your buck. Find someone who is competent with it and let them have the motor for a week and work their magic.

JayG · 04-20-2008, 08:06 PM

Quote:

Originally Posted by Porschekid962

If I understand you right you are saying that a rotary makes higher tq or makes tq higher than a flat six motor? If it is the former I think you are mistaken, if it is the latter than who cares. Low end tq wins race but this is somewhat of a streetcar am I right? A mazda rotary will bolt up to a porsche transmission if you have to proper adapter plate, take a look at a formula mazda car, 13b rotary mated to a vw bus transmission that has been pimped out by hewland and star cars. No problem there. To be honest I would rather run my motor with a dizzy and carb than Megasquirt or Haltech. Unless you can spring for a competent system (Motec, Autronic, Bosch, DTA Fast, Pectel, McLaren Electronics, EFI Technology and many others) My preference goes up with the listing by the way, Motec is old school by todays standards, most people just use the loggers and dashes but leave the engine control to something better.

As for running with Haltech, how is your cold start? Hot start, part throttle mixing, decel fueling, enleanment and enrichment? I could care less about WOT its the in betwixt that wins the prize and from what I have seen and driven first hand Haltech loses by a lot.

Try and find yourself an Autronic SM4 ecu, one of the most capable ecu's out there for the price, probably the best bang for your buck. Find someone who is competent with it and let them have the motor for a week and work their magic.

The turbo 13b makes much more tq than the stock 2.7 that came with the car, that's why I said its still an improvement. With the light weight of the car the tq is not as noticeable with you still have 260 ft lbs on tap in a tiny car. Again this is with my street car. A race car with a bigger turbo and setup properly can make 600 hp and still have decent torque. Maybe not as much as some others out there but for the money?!?! You'd have saved so much money with that you can spend it else where on the car.

You would rather run a dizzy and carb on a boosted car rather than a Haltech? HA! That's the most absurd thing I have ever heard. You sound like you are kind of being a little snobby. My car starts first time cold or hot, gets 25+ mpg, never floods, hiccups or stalls. Haltech is hardly a vastly inferior tuning system compared to some of those you mentioned. From what you have seen and driven first hand must have been a poorly tuned Haltech. Honestly, these things dont tune themselves.

This isn't the first time I've used a Haltech and over the years and I've gone fast with some street cars. It's not just for straight line retards on a drag strip as it has plenty of street manners. That's why I like it.

Porschekid962 · Porschekid962's Garage

Firstly I didnt realize your motor is a turbo, most rotary engines I have been around are in pro mazda, formula mazda and other iterations of that where you arent allowed to use a turbo. I would never use a carb on a turbo motor, its crazy ha. If this engine is going into a racecar I would want to use an ecu that would talk quickly and with no hassles with my dash and data system. I know that Haltech does not like to talk with Pi at all, Haltech doesnt even have a CAN bus. For a street car I am sure its fine but not for racing just too many hassles.