hi, i dont actualy have a N/A RX7 but my friend has a 86 base that took a **** and are puting a bandade motor in it while we are rebuilding another on. We want to make it as streetable but as fast as posible w/o nitrous or any forced induction. he is what we have come up with so far (just internals): Atkins Rebuild, Street port, and E-shaft, rotors, counter weights from a RX-8. i was wondering mostly if the RX-8 inerds have been tried befor and with what sucsess? we are also going to have other upgrades to suport the engine, 225walbro, low imp. 550cc injectors, rtec7 stage 2 (N/A), racing beat exhaust (already have), HKS intake (already have), and phat 10mm plug wires (already have). i was just wondering what all ya'lls thought of our plan.

 

Where to start... the RX-8 internals are overkill and a waste of money. It is very slightly lighter and has very slightly higher compression, neither of which will make much difference at all, especially not for the money involved. I would try to find s5 rotors, but even s4's should be fine if ytou can't find s5's for cheap.
The best thing you can do for power is a street port (which you are already getting) and get an s5 UIM so you can take advantage of the VDI. The s5 UIM is good for a dyno-proven 15 HP, which is a pretty big deal for an NA rotary.
Also, the fuel crap is another big waste of money. No NA rotary will need extra fuel unless it has a bridge port or better. I guess since you are getting the Rtek, you might as well get the 550's if you can control them, but it will run rich even on the stock 460's. The Walbro is totally unneeded. If you really want extra fuel, you can get a used TII pump, which is a hell of a lot cheaper.
Just for comparison, my old engine was streetported and it was running pretty damn rich just in the stock setting. Most NA rotaries will actually get more power form LESS fuel, and yes it has been proven on a dyno.

Spend the extra money you would have spent on a good suspension, you will much happier.

 

suspention is already coverd, its got tokico HP shocks, eibach springs, and no name front and rear strut bars. we just need new back tires because the rears are bald . thank you for your imput so far. i think we are still going to use the RX-8 parts or get S5 rotors. but we might just sack the comp mods and run stock.

 

does any one else have any ideas? and if you retard the timing on these cars does the power band move up in the rev range like a normal piston motor?

 

this is neglible at best.

 

this is neglible at best. but sorta works. the best way is to lock it in stock timing, make a few dyno passes and then adjust timing to what you like, but the timing does affect idle quality as well

 

I'd say that the rx8 e-shaft isnt a waist of money, .6lbs of less rotating mass will spin the rotating assembly faster, and if your NA and want power you probably will end up with running minimal accessories to minimize drag, not to mention if the engine is apart already 200 dollars (or less, im not sure on the exact price but mazdatrix has it cheaper than OEM w/ employee discount by a few hundred dollars) I hope if you want NA power and a rebuild and all that you upgrade your clutch assembly, and go with an aluminum flywheel, your engine will rev up really quick and freely.

 

yeah i had forgot to put it up there, definatly a alu fly wheel.

 

Sideways7 spelled it out pretty well up there ^. In addition to that, if your rb exhaust doesn't include a rb tube header, you might upgrade to that. It flows much better than the stock "log" manifold. You might also want to use 460 primaries due to the fat bottom end, and then 550 secondaries for the top end with your streetport.

 

Megasquirt


Toe eliminators

 

we have all new/newer suspention bushings in it and have the rb tube header along with the exhaust.

 

The suspension is far from covered if you're relying on Tokico. A faster N/A needs to built all the way around. Make the car as light as possible, carbon hood, fibre glass fenders, stripped, etc. Lighter also works in the engine, aka RX8 e shaft and lightest possible flywheel. I think JUN still makes them for Japanese FCs and they weigh 9 LBS. Don't mess with the timing or fuel unless you go bridge or bigger. Fuji racing just released their 13B itb kit for $750(I think...). This will increase throttle response and give you a little more torque all around. THEN... you need to make the car move. Tii tranny and rear end mated to an FC3S.org 9lb drive shaft. Finish it with RB 4.33 gears and tune it.

Don't buy a CAI, its a wast of money, and will add weight you don't need.

Don't get an exhaust bigger than 2.5 if you want to drive it on teh street and not rock the dead

DON"T rely on tokico, or any other shock/spring combination. Even cheap coilovers have all their components designed together. Springs/shocks are never a 100% matched combination, and will not give you the camber, height, stiffness, rebound control you need.

 

I have to ask, did you search the Beefy NA thread? Most of this stuff has been beaten to death.

Dbl post ftw

 

Ummm you should check out my thread https://www.rx7club.com/2nd-generation-specific-1986-1992-17/n-street-ported-engine-second-time-683537/ i'm bound to make atleast 220. I think that is a guess.

 

I have and I like it, but I have to do it my way and blow it up before I conced I'm wrong. I'm after 250 to the wheels with itbs and haltech(when I can afford it ) and I wont stop till I get there with out FI.

I must say though you're off to a great start.

 

my friend or that other guy?