weaklink

of the three videos I downloaded of that car from that site, it blows up twice, and on the third one it quits running about a 1/4 way down the 1/4.

moremazda

iTrader: (4)

They only slip to about half track, after that it's a race to the revlimiter, AND the changing gear ratio from the tires balloning due to the rpm that they are spinning.

Smilodon

The simplest way to measure their hp would be to put a piezoelectric pressure sensor on the motor mounts, and whatever pressure was generated as the engine tried to twist its way out of the car, coupled with RPM, etc. and you would know how much HP exactly it was making. Supposing they even care. And assuming you could set it up in such a way that the engine was still solidly mounted.

I read a year ago on some website about someone with some gigantic 700 cubic inch twin rotor marine diesel. Haven't seen much of it since.

13B-RX3

iTrader: (2)

Here are a couple useless but neat facts about top fuel. From start to finish a top fuel engine turns less than 500 revoloutions. Also when they grind the camshafts each pair of lobes is retarded because the cranks twist as much as 15 deg from front to rear.

Smilodon

The crank is solid billet carved and then nitrided. And they still twist it. Egad. I figure one would need one big, fat, billet rotor shaft, then. Nitrided and shot peened and surface polished, cryotreated, etc.

At least there is no camshaft to twist mit der rotary!

Smilodon

And, will the motor idle... I mean.. below 3,000 rpm??

GUITARJUNKIE28

i didn't know that.. that's cool!!

Michael_Rudy

Another neat top fuel car fact is that, when the are a 1/4 way down the track the electrodes of the spark plug is completely gone and they are running off the heat of the exhuast valve.

13btnos

iTrader: (1)

All this talk about top fuelers is getting me excited 1 more week till the finals at Pomona http://www.nhra.com/apcm/templates/p...0&navsource=23 it's good to live in Southern California can't wait to go. If you guys haven't had a chance to see these cars in person and live in Cali man it's worth the money to go nothing like it in the word. Nothing like the smell on nitromethane in the mourning. My personal favorites are the Funny cars you should see how those dance around going down the track.

crispeed

You'll be surprised as to how many people have been playing with nitromethane in rotaries.

chairchild

well heres an idea for you - instead of having 6-odd rotors all in line, why not have three 13b engines in parrallel? All joined by a small cog between some stupidly lightweight flywheels on each motor, the total weight of them making a reasonable weight for a flywheel


Would solve the problem of trying to get a custom E-shaft made up to cope with all that power and flex!



And I think it'd be interesting to make a racing series where there were NO limits on the engines/cars - as I personally thinkg it would push the limits of technology forwards!

GUITARJUNKIE28

i saw a car at 7stock a few years ago with 2 13b's. don't see why that wouldn't be feasable, except if you're doing professional racing, what class would it be in?

RandomHero

iTrader: (2)

Rollys Royce had a patent on a pretty large diesel rotary. In Yamamoto's book they showed the tech standing next to it, and it was as tall as him. With one large rotor doing intake and exhaust, and a smaller one doing compression and expansion.

That really would be awesome to have an unlimited class for drag racing. Of course safety would have to be a huge thing. But it would be great for advertizing and im sure some crazy **** would turn out.

Falcoms

Did you know: it takes 1500 horsepower to turn the supercharger on a top fuel car!

Smilodon

LOL rotaries could just use the front two rotors for supercharging the air, and the last four rotors for power production.

Kenku

Could be... anything you can share? I've not come across any mention of it aside from threads like this where people bat the idea around out of curiousity. I don't doubt there's experimenters, but anything proceeding as seriously as (to name a convenient example) Ibarra's engine development?

GUITARJUNKIE28

buy me a 5'er and i'll burn it in my fd

GUITARJUNKIE28

^ it'll be a 5 minute trip

13btnos

iTrader: (1)

There's a little island between the Caribbean Sea and the North Atlantic Ocean I think it's called Puerto Rico. But from what I have heard there are quite a few, amongst others, that are playing around with nitromethane and rotarys. Can't wait to see who is the first one to be successful with this endeavor. It surprises me what kind of passion they have for this little engine and what kind of cars are coming out of this little island. http://www.pistonvsrotor.com/ look under projects section for Puerto Rico you'll be amazed. Click on Secciones and then click on Proyectos.

Kenku

Strangely, I've heard of that island... but going from pistonvsrotor and poking around the projects section, from how they use "nitro" I am under the impression they're talking about nitrous, rather than nitromethane. Not to say there aren't a bunch of neat cars, but... well. I've never heard of people playing with nitromethane in rotaries. I doubt I'm anywhere near as up on things as crispeed is though.

digitalsolo

iTrader: (2)

Now you're catching on to how a twin screw can make so much more HP then a roots (and a tri lobe roots at that!).

I'd be interested to see nitromethane rotaries, I can't imagine the apex seals would appreciate the violence of running on nitro. Certainly be interesting if someone could make it hold together though.

13B-RX3

iTrader: (2)

Makes you wonder what kind of horsepower a fuel car could make if they allowed turbocharging!!!

Smilodon

Problem with that would be instantaneous throttle control which is necessary component of having far more power than you have the traction to use.

"Fuel" (allowed to use superchargers and nitromethane) and Alcohol (Allowed to use screw-type superchargers and alcohol, or N/A on nitromethane last time I checked) cars use solid aluminum heads carved from billet. No cooling passages.

Weird, huh? The alcohol in the fuel mix has so much latent heat capacity that it charge-cools the combustion chamber. At least enough for the seconds that it takes to stage, burn out, back up and run the 1/4 mile.

When someone used an RX7 a few years back to try to get some speed records at Bonneville, it was turbocharged. The guy driving it said that out on the salt (ie: situation where there was more power than traction) the turbocharged motor didn't have quick enough throttle response upon throttle lift to mitigate wheelspin, so it spun its wheels too much.

Roots blowers have quicker reponse to throttle inputs than turbos. Ever heard anyone with a roots blower say "Yeah, I tried to catch him but there was too much blower lag?" LOL Not hardly.

13B-RX3

iTrader: (2)

Have seen alky supercharged cars with ice on the blower before.

There is also such a large volume of air going across the throttle plates they freeze up. If you ever look close you can see a crewmember spray them with deicer.

13btnos

iTrader: (1)

You are correct in that they use "nitro" for nitrous. No where in that site states that anyone is using nitromethane I was just linking that site so others can see the kind of builds people are making on the island of Puerto Rico. But there are those that are tinkering with nitromethane hopefully someone will be successful.