300hp in an FC. The most reliable way.
 

So I'm doing a research project for school and my topic is the best/most reliable way to get 300hp in an FC, yet still keeping it reliable for everyday driving. Money isn't an issue for the assignment. So anything from 20Bs to a built NA is available. Any help/other setups is appreciated, the more specific the better. Only real restriction is that I want to stay rotary.

Thanks guys. :icon_tup:

I assume that putting in a 5.3 that WILL make 300hp for 300,000mi in a truck is out of the question :)

(Anything in a truck is assumed to run at full power forever, and the 5.3 is rated at right at about 300hp. So is the 4.8 actually, but the 4.8 is only available with an iron block, while there are aluminum-block 5.3 variants)

It's a balance between heat loads and RPM. Engine wear and therefore engine life is somewhat exponential with RPM, so high horsepower N/A is tough to make 300hp and last a long time. Same with turbos, except the problem there is thermal loading. (How long do FD engines last even with reliability mods?)

20Bs can do the power with ease N/A (thus, less RPM) but you still have the thermal issues to deal with. Keeping a 20B cool is a subject best left to those who are (or aren't) dealing with that issue personally.

Swap in a stock 20b with exhaust and intake.

So proper cooling will be key? Upgraded radiator, oil coolers etc.

assuming you stay rotary. the most reliable way, is the simplest. ideally you'd start with a running factory turbo car. the engine needs to be rebuilt with new rotors and probably all 5 housings. maybe a small street port, less is more here.

you need to replace ALL of the water hoses, radiator, water pump, thermostat, thermostat neck if its an S5.

you need a 3" exhaust, bigger fuel pump, larger injectors (550/1600 or since the EV14's are in fashion maybe 700/1000). you could do 300hp on a BNR style hybrid, but a 60-1 on an HKS manifold will do it with less boost. you need an intercooler, a good efficient core can be smaller than a cheap chinese one. in fact the JDM 1.5 stock intercoolers actually works quite well.

you need a good ecu, PFC for instance. tune it well and leave it alone!

i did one that was a new engine, except the Eshaft, 60-1, and after 10,000miles of street use it did 392rwhp@12psi....

Thanks for this, no one has mentioned anything about a 13B turbo setup yet :icon_tup: Are you thinking a 13B out of an FC or the 13B-REW/RE?

Still kind of leaning to 20B na tho. That way boost/forced induction issues won't be a problem. Like you said, less is more ;)



I would plan to rebuild whichever engine I chose, what are peoples thoughts on the use of Rx8 rotors?

For the drivetrain (regardless of motor) I have:

- TII Trans
- TII Starter
- TII Clutch/flywheel setup (something aftermarket, haven't decided yet)
- TII Driveshaft (or custom if needed i.e. 20B setup)
- TII Axels and Diff (Possibly aftermarket

And for the ECU thinking Haltech (Platinum Sport 2000), but after j9fd3s's post I'll look into the PFC.

see you're over complicating. no engine swap, just buy a stock FC engine, and bolt it in an be done. for 300hp going to an REW or RE just isn't needed and is more time and money to install it.

the 20B is in the same boat, its more money/time, plus you have to design the header and intake...

i'm not saying a 20B NA isn't cool, or an REW-FC isn't cool, and if you like the challenge of figuring out how to get it to work, that is also fun, but the "most reliable" is just to be stock.

so forget the Rx8 rotors, they do not just drop right in, and if you can find someone who did all the work AND made the same power as any old style rotor (never mind more power) then i will give you an Ecookie

Alright thanks, I appreciate all this. Time and money aren't really a concern, since this is all relatively hypothetical, and the final result is just a 300hp Rotary FC that I can jump in turn the key and go.

How long will that last, though? I thought stock TII engines were basically worn out by 150k, and they don't make nearly 300hp.

If it weren't for the winter months, I'd do 150k in five years. :) I drove 2500mi in the period March 22-April 20, and it isn't even driving season yet.

I guess it depends on the user definition of reliable. I would like to see 200k without appreciable performance loss, preferably 300k, barring user-generated errors. I got close to 60k from a 200+hp N/A with several major user-generated errors along the way :)

My suggestion would be a mildly streetported 20B N/A, using new S5 N/A rotors with new housings/ceramic seals, keep it under 8,000 RPM and everything should hold up very well for quite some time. You can do this with the stock intake manifolds, you would just need an exhaust header, which isn't a big deal if you keep the porting mild.


P.S. RE-Amemiya used to compete in the GT300 (300 bhp) with a 20B N/A, and the 787B used a 4-rotor N/A as well even though turbocharging a smaller displacement engine would have been an option.

i'd go with a 20B with ceramic seals also for the most reliable rotary. issue is the fuel system, forced induction, heat and other issues of the rotary engine with forced induction that make them unreliable no matter how thorough you are in setting them up.

doesn't matter what seals you use, what safety measures you strap on or how thorough you are. turbo/SCed rotaries will eventually blow up for a less than good reason.

eventually you have to realize that these engines are inefficient, run hot and have flaws built into them right from the start. naturally aspirated you at least cut out the biggest problem in the equation, the weakness of the block and apex seals as well as a big chunk of heat generation(turbo).

my personal end of an era building these cars is my 4 rotor n/a project, i will probably get rid of everything else once that is completed. most people don't have the means to do this or funds so the 20B is the next most affordable platform.

na stock port 26b with supporting mods for fuel, ecu, drivetrain and such

Over-complicated from a machining/parts availability point of view, and completely un-neccessary for 300 HP. And it won't be any more reliable than a mildly street-ported N/A 20B (in fact it may be less reliable due to cooling the longer block.)

Unless, the coolant route has been properly mod'd as Mazda did in the 787B and BMI Racing and other's have followed = NOT A PROBLEM.

I'd like to do this project with out having too much fabrication, like no CNC or custom parts etc, motor/trans mounts and other little things aside. I don't want to be fabricating an e-shaft or having a project that's costing 20k+ for just the motor setup

is this a research paper or an actual project that you simply didn't want to ask about?

It's a research paper that I would like to eventually like to turn into a real project.

n/a streeport 20b. Done.

What's a good streetable clutch/flywheel setup?

ACT street/strip full face with a 10lb light steel flywheel.

I hit about 300whp on the stock turbo, ECU, intake manifolds, intercooler, ect... Never opened S5 TII motor.

Modify the stock parts with hand tools (welding skills is the only hard part), water/meth injections, very little adjustments with a SAFC NEO will get you more than safe.

Search my name on my RHD FC. All the info you need is in there. Drove it everyday. It was quiet, idled at 700-800. Started and drove like a stock car.

but would it last 300k miles? i'd go with the 3 rotor, streetport, ceramic seals and standalone EMS for simplicity which should basically run until the bearings are worn to the point of 100% copper showing. why also wouldn't you want a more linear torque curve with actual throttle response in addition to that 300whp.

yes it is a rather expensive naturally aspirated setup but also one you won't have to worry about every time you stab the throttle, unlike force inducted rotaries.

+1 i've tried a bunch of clutches and that is the best setup.