epion2985

so going single and was reading and educating myself here and there. I have come to set a goal, its pretty stupid when people come on and ask I want a fast car what turbo should I get... and such... anyway back to the topic.

I was looking at the T04e, T04S and T04R. My goal is 400rwhp. I would like to have allt he 400 horses at 5000rpm but if its possible by 4000 that would rock my world.

Any sugestions. And you are NOT limited to T04e, T04S and T04R.

thanks!

epion2985

PS:

this will be going on th street ported motor. Its not yet but will be when I will have some time.

also I think i want 400 now but you kow how it is, once you have 2 rotors you have to her 3, once you have X amount hp you need X+some more ^^ ...so i think I would like a reserve. 500rwhp sounds good. I wont use it all the time and probaly will turn the boost down and drive around at 400 or less but I would like the slack.

maxcooper

400 HP @ 5000 RPM = 5252/5000 * 400 = 420 lbs-ft of torque
400 HP @ 4000 RPM = 5252/4000 * 400 = 525 lbs-ft of torque

Those are some very lofty goals. I like your approach of having some specific goals in mind, but you probably need to adjust your goals down because it will be very hard (expensive & unreliable) to hit those numbers.

Someone has a cool site where you can see dyno charts from a lot of different setups. If someone has the link, please post it. Looking at the charts might be a good way to find the power curve that best fits your needs and desires.

-Max

epion2985

thanks, I dont know about unreliable if done right and not slopy but costly probably, but who said fast cars are cheap ^^

what would T04e, T04S and T04R produce at 4000, 5000, and 6000 rpms? On a street ported motor?

PS:
alot of people assume to get more power out of your car you need to make more power, which is not true really, you just have to get more from the engine to the wheels. Hence another question, rotaries do well at high rps, turbos do well at high rpms, to get the high rpms faster means much better results. Question is with a light weight carbon figer driveshaft and a light , say 8lb alum. flywheel what would the increase in % of power the engine makes that would get to the wheels?

"light drive train, get faster to high rpms, get more power to wheels" wise words but someone on this forum, cant remembe the name, jspacer I think...

maxcooper

I found the site I was talking about:
http://www.catenet.net/dyno.php

Reducing the drivetrain inertia helps most when the car is accelerating quickly (low gears). It matters much less in higher gears when you are accelerating slower. I like light flywheels because they make the car feel more responsive, though. Synthetic lube in the tranny and rear end will reduce drivetrain losses somewhat, but I'm not sure there's much you can do to make a big dent otherwise.

Traction is a major issue when you start to make a lot of power, so at some point the question becomes how well can you harness the power to making the car move forward rather than just spinning the tires.

-Max

epion2985

indeed, btw, about traction look at these tires, completly street legal btw!!

http://store.summitracing.com/

epion2985

question:

went to that site, looked aorund, I think I like the T04S, question is why does car #10 has such a nice curve??

http://www.catenet.net/graph.php?car...1&SUBMIT=GRAPH

maxcooper

Car #10 is running 21 psi -- 5 more psi than any of the other turbos in that comparison. He's got a 1.15 turbine housing, too, versus 1.0 for the other cars.

-Max

epion2985

would it be ok to run 20psi if you have a v-mount (rotary extreem) the ic can handle 900ph and the radiator is very good too, that plus the dual monster oil coolers. Would that pretty much eliminate detonation at that amount of boost?

maxcooper

There are too many variables to give you a definite answer, and I don't know enough even if we did nail down all the variables.

I personally would not expect to be able to run 20 psi on 91 octane CA pump gas no matter what I did.

-Max

epion2985

what would you think you could run with very good cooling setup on 91 octane CA pump gas?

with water injection a few people ran 20, or 20 something psi on this site. I remember a few threads about it, and I personaly did a nice reserch on water injection. Funny thing one of them refilled his 2 gallon water tank every other time he filled up with gas, so 2 tanks of gas per 2 gallons of water at 91 octain at 20 or 20+ psi. I think he had nice charts too. Couldnt find it though. Maybe you remember? but water injection seem to work really well.... those aquamist kits look nice, let you map everything, by revs or boost. Ever tried one or know anyone who has?

maxcooper

I think I can run maybe 17-18 psi on pump gas before things start to go bad. In fact, I pretty much know that from doing it with my RX6 setup. Water injection does seem like it could raise the limit, perhaps even up to 20 psi. I think the key factors are having a turbo that is efficent (doesn't add an excessive amount of heat to the intake charge), very good tuning and control of your fuel and ignition maps, and excellent intercooling (big, free-flowing IC, and perhaps some water injection).

Okay, so I'll go along with the idea that it might be possible to run 20 psi on pump gas (maybe even the crap 91 octane we get here in CA). However, the margin of safety gets pretty small up there. A bad spot in your fuel map, a slight overboost, or a bad tank of gas could very easily blow your engine. I don't think I would be comfortable with that margin since the consequences are so grave ($$$). For my own car, I would rather run a little less boost and have a bigger margin of safety if something goes wrong.

Most of the folks running 20+ psi are doing it with high octane race gas ($$$). If anyone is running that much boost on pump gas, please post and share your experiences.

Having 400 RWHP on a street car as light as the RX-7 is very entertaining. Traction becomes a major issue even at that level in the first few gears, and there aren't really that many opportunities to open it up in the high gears. Safety and the chance to go to jail tend to limit those forays.

-Max

pp13bnos

iTrader: (1)

To be honest, even with a mild 300rwhp, and stock rubber, my non-seq 3rd gen had major wheel spin in 1st and 2nd. I can't imagine 400rwhp with stock sized tires. But....I'll get the chance, as soon as my car is tuned. CJ

BTW, hows your car doing Max. You have'nt been posting lately, and last I heard your motor let go?

maxcooper

Yeah, I popped it due to some fiddling with the fuel maps (my fault). The rebuild is underway and I'm trying some new stuff. I got some of those apex seals from Rotary Aviation and might get my rotor faces ceramic coated. I'm going to switch to a different turbo kit, too, but I haven't ordered anything yet. I'm going to make up my mind and order a turbo this week

-Max

epion2985

have you guys considered ceramic coating the irons and the sides of the housings?

ceramic coating on the housings + ceramic apex seals would mean really low friction, worth a try?

and what do you guys think about the T04s?

maxcooper

I don't think you can put a thermal barrier coating on the rotor housings or end plates. The coating is 0.002-0.003 thick and it isn't flat or slippery -- it would get scraped off very quickly and would be a mess. The rotor face seems like the only area you can put the thermal barrier coating on inside the combustion chamber.

I am interested in the rotor coating to reduce the amount of heat (energy) that "leaks" out of the combustion chamber. The more you can keep the heat in the chamber, the more efficient you'll be and you should make more power, all other things being equal. I am a bit concerned that the rotor face coating may cause some clearance problems at high RPM. I might just coat the recesses if my doubts get the best of me. However, I'll probably end up coating the whole rotor face and just keep my fingers crossed.

It might be possible to use the same stuff they use on piston skirts on the side plates. However, I am not even sure about that since the side seals will be sliding over those surfaces. I don't think there is anything you can do for the rotor housing inner surface.

There are lots of people running the T04S with some very nice results. It seems like a good turbo at a reasonable price with relatively inexpensive service or replacement options available if you happen throw some apex seals at it. Coming from someone with a (non-rebuildable) RX6 turbo, the ability to repair or replace the turbo without having to wait a long time and/or pay through the nose for a replacement is an important factor to consider.

I've been kicking around a few different options for my new turbo setup. I'll post my choice and what led me to it after I place my order.

-Max

epion2985

the only way I thought you could ceramic coat the interior of the rotor housing is if you have ceramic apex seals. Glass smooth seramic sliding over glass smooth ceramic should have little friction and hence should not scrape off. Ofcoarce you would have to make sure to gethe the smooth finish on your coating nothing rough. I tied it, not on a rotary just some garbage I messed with for funs sake, ceramic on ceramic while lubed with oil seems VERY frictionless... then again I never tried to put this to practical use.