hi all, i'm kind of new to rx7's, but i've got a plan and so here goes.
91 turbo II, rebuilt, ported motor from mazdarx7engines.com or revolutionrotary.com, big turbonetics turbo, motec M4 fuel management system, external wastegate, etc.
questions:
to attain about 400RWHP, what size fuel injectors should i run, and also, what is the upper limit of boost i can run on 93 octane (i live in midwest, haha) without suffering from the evils of detonation. i am also probably going to switch to a hks front mount intercooler.
any help would be great.
also, what is the volumetric efficency (VE) of the 13B, i need to know this to calculate turbo size
thanks

 

fuel injectors can be a set up of 4 720s, or 2 1600s secondaries and 2 550s primaries, ive seen both work alright in a 400hp car. there may be another or better setup, but thats what ive been exposed to. boost limit is gonna be a tune kinda thing. depends on your fuel maps and such. and yes, you will definatley have to swith to a front mount. i dont know about calculating turbo sizes, but i know a good TO4E or 60-1 can easily swing 400rwhp. as far as the volumetric efficency, i have no idea.

 

Also check some of the "mods lists" for those running 450+HP. You might also consider a 3rd set of injectors on the intake manifold once you begin dynoing your car.

BTW - many people slighly retard their timing 1-2 degrees when running 250+HP. That also prevents detonation. 18PSI should get you close to your HP needs assuming FMIC, large turbo, etc...

I think the "7.8 sec" 20Bs 3 rotor rx-7s running on pump gas are using T04s with NOS, FMIC, etc.. etc..

 

You might want to look into race fuels, depending on what level of boost you will be running. They have to sell it somewhere near you right?

 

First off, plan on doing a LOT more work and research. Saying you're getting a Motec and a big turbo sounds serious, but "maybe I'll get an intercooler" sounds like you're new to this .

I'm assuming you have the car, right? Does the car start, run, and drive well? Make good power? Have good tires, suspension, brakes, hydraulics, electrical system? Good.

Best thing is to just start slow and work your way up. Making serious power with a 13b is not easy by any means - hell, making serious power on any car is not easy. Start simple and work your way up. Not to mention trying to do everything in one fell swoop will lead to a troubleshooting nightmare.

Also, realize that this will all be money you're throwing down the toilet - if you ever sell the car, you will sell it at a loss.

With that in mind, just start reading things. There's no good recipe for "buy x, y, and z and make 450 hp" - there's so many different ways to do it. Be prepared to spend a LOT of time learning.

Dale

 

yes, i am serious about the car, and about what is required to do these kinds of mods. i'm no dummy about cars (i'm a Mechanical engineering student), i just had a few questions about rotaries in general. yes, i AM going to switch to a FMIC, probably a spearco, since they are a better design than the hks/greddy and are less expensive. i'm not planning to do everything at once, since the car already has an hks turbo and hks f-con V ecu. i will probably get the motec and turbo later, since i will be learning how to tune the motec this year on my school's Formula SAE team (check it out at: http://www.umr.edu/~formula). but thanks so far with all the info.