hatemy7

Good Morning Fellas,

Just like the title stated. I am starting my build on my engine. Def am going to build it up for some big numbers. Would love to see/know what you guys did to reach the HIGH HP numbers on your rx7s.

Also how are rotaries with e85? is there any issues. ( I ask since I am coming back from EVO world lol )

Thank you in advance!

Keep on brapping

Skeese

iTrader: (11)

You'll want to check out my thread on building an E85 fuel system for a high horsepower rotary.

FUEL FOR 750 RWHP ROTARY

At hose levels you really need to be talking about building a purpose built methanol car as you're honestly maxing out the capability of E-85 as a fuel and will have to bandaid that with conservative timing and extremely rich AFRs, which with time will ultimately result in failure.

The truth of the matter is that 900hp is ALOT of power for a 2 rotor to support, even with an unlimited budget. The first 500 comes pretty easy with a rotary and a simple single turbo, but when you start talking about 700+ you will need at a bare minimum...
- HUGE bridge or semi peripheral ports
- irons ported to cosmo spec side intake ports
- lightened, clearanced, and dynamically balanced rotors
- over sized engine studs or additional dowel pins
- CDI ignition (will blow out spark on IGN-1A's around 600 on E85)
- dedicated fuel system, see my link above
- big flow manifold, very large turbo, large intercooler
- modern ECU with engine protection

...not to mention that the stock transmission becomes a glassbox past about 600 and the factory rear end can be trashed on a hard launch at 400hp. I've been targeting and building for 750 rwhp on mine and I have well over $20k in mods on top of the car in the setup. Also should mention that at these levels, you MUST be ok with occasional engine failure requiring high dollar rebuild work, because ultimately if you push this much out of it then it will happen.

Go for it! Just be forewarned its a huge undertaking on one of these things...

Skeese

hatemy7

Dude you are awesome! i hope you know that. Awesome build as well!

j9fd3s

iTrader: (3)

the JDM cars i know of that are that high HP, are running this setup, https://www.carshopglow.com/parts/rgn-fd-009/?lg=en

Skeese

iTrader: (11)

Truthfully, you'll absolutely need some form of peripheral porting to get anywhere near 750 on a 2 rotor. You'll need a turbo capable of flowing 100+ lbs/air per minute and a keg capable of withstanding extremely high boost (40+ PSI) and ALL of the supporting fuel and ignition stuff will have to be top notch and spec'd to suit your exact application or else that much boost will just repetitively result in engine failure. Check out Copelands build thread at the link below for a good reference. That is one of the very few stupid high boost high HP street cars out there and his setup is proven as he kept a single motor together at 40+ psi for something like 4 years.

COPELAND BUILD THREAD

Skeese

diabolical1

iTrader: (3)

So considering this ...
... you may also want to think about adding displacement/rotors as well.

Shainiac

iTrader: (7)

I know this is a very unpopular opinion, but the reasons listed above are why I went V8. I home built a ~550whp 13BT on a relatively tight budget that was still very streetable. It had an unpinned block, quick-spooling EFR, street port, and quietish exhaust. If i wanted much more power than I was making, I was going to have to make big upgrades that would ultimately make the car less reliable or less streetable (and cost much more). With the turbo V8, I get better street manners, WAY more torque, and a lot more peace of mind knowing that if I break something, I have a $350 spare engine already sitting in my garage. There are certain things I miss, like the smoothness of the rotary, but I actually prefer how the turbo V8 sounds and drive on the street. Definitely not everyone's cup of tea, but definitely made financial sense to me.

Skeese

iTrader: (11)

Even as die hard rotorhead, I'll agree with you that it is WAY more intelligent to go V8 for anything past 600hp if you're still in 2 rotor land and are on any sort of a money budget. Pushing a 13b to extremely high hp (700+) most definitely has a great number of cons (cost, reliability, complete loss of streetability, level of build detail and effort required, etc...) that you must accept as a trade off for that power level. At the end of the day, you have to choose what is important to you in the car and what you want from it.

Skeese

Shainiac

iTrader: (7)

I would have loved to go 20B, but the prices are astronomical compared to what there were several years ago. Even if you got one cheap and held on to it, the cost of cracking an iron and having to buy new is absurd. You're right about anything rotary over 600hp being a tipping point - you're paying the bulk of the V8 price up front because you're going to need a better trans, twin disk, 8.8" rear, and $$$ shortblock with machine work. I'm willing to go out on a limb and say OP hasn't been around many 900whp rotary since most haven't. A 900whp 13B runs on methanol, has a GT55+ turbo, and usually uses a Lenco or similar race trans. It'll idle around 2000+rpm and burst ear drums. You don't want that lol.

hatemy7

Thank you boss

This is good stuff!

I appreciate your opinion but im staying 13b brother lol.

j9fd3s

iTrader: (3)

Time Machine: Flat Out On The Tokyo Aqua-Line - Speedhunters

they claim 710ps around 22psi, pump gas no AI.

hatemy7

but my question is. Are Rotary guys doing the same thing we do in the evo world? Which is use 2200 injectors for e85???? or are they still using small 780 primarys and 2000 secondaries?

Copeland

iTrader: (42)

Skeese answered your injector question at the very beginning of the thread:

A 720/2000 setup would be inadequate.

hatemy7

S

Sorry guys I was a little hungover lol. Long night