OK guys I am sure this has been asked however lots of answers start with "change all fluids give a tune up etc" with all of this done my question is what all can u do with a N/A rotary to get more power BESIDES taring the engine apart and porting?

so far I have done thw following to my 86' n/a 5spd 13B:
racing beat downpipe
custom pre silencer
K&N drop in


my plans this winter are to do the follwoing:
port the intake (all pieces) and the throttle body
open up the 6 ports a touch to allow a little more flow once they open up.
replace my stock mufflers with aftermarket mufflers
replace my custom pre silencer with a racing beat pre silencer
finish my custom air box shield so I can run a cone filter from the mass air
replaced my worn bushings with energy suspension bushings
upgrade both frt and rear sway bars with adjustable links
frt and rear upper strut tower bars
15" vert bbs rims with Falken Azenias
new brakes (cross drilled rotors with ceramic pads)
electric fan to clean up the engine bay
KYB gr2 shocks with lowering springs

maybe a little more.

anywho my plans are for a friday/saturday car but mainly auto X however I would like to get as much umphout of the stock n/a as I can.

what can I do to increase my horsepower/torque?

 

Turbo............................................. .................................................. ........................................


Remove the P/S, Rats Nest, A/C. Wont do much, but it will free up some HP and make it eaiser to do your winter projects.

 

this car has no p/s and I removed the A/C

whats the "rats nest"

I dont plan to turbo the n/a motor and i will maybe do a swap later but not now.

anything else? are there any 200hp n/a's

can u get a reflash or a ecu chip or anything to bump up the power?

Dave

 

carb it, and the rats nest i belive is around the throttle body and emissions around the egine. if you do a little searching theirs a write up on how to swap the s5 lower and upper intake mainifold, its suppose to give you 10-14 hp to the wheels, but thats just hear say. the only 200hp n/a;s that i know of are rebuilt with a large street port, and a 48 webber carb, but thats 200hp to the wheels.

 

after you do everything you mentioned above, you can get a piggy back... like a s-afcII or something. When I had my 89 GTU... it was running pretty rich after some manifold porting, free flowing exaust, yada yada... it freeded up about 12 or so HP... Not much, but every bit counts.

 

Have you removed/upgraded the cat? That's the #1 thing. Headers only add a tiny bit of power.

A carb will increase peak power a little but it will lower power everywhere else. And it will hurt your fuel economy and emissions. Don't do it.

After fully upgrading the exhaust and intake, all you can really do is get a street port and/or SAFC2/stand-alone.

 

yeah the cats are gone as stated above I have racing beat downpipe and custom pre silencer I was thinking of a RB header and removing the stock mufflers with some supertraps or something strait through.

I think will mod the intake to remove the stock box, do the intake port and tb port..

and I did a search and round no info on what a "rats nest" is

 

I believe the Rats Nest they are refering to is all the vacuum stuff mounted on top of the engine and other emissions stuff (although it isn't nearly as bad as on the carbureted pickup trucks).

If your already going to have the engine appart, pineapple 6 port inserts are a cheap add on.

 

You won't be able to make 200rwhp out of an NA without rebuilding it. If you plan to rebuild it, get the highest compression ratio possible (10:1 renesis rotors) then port the motor. It's up to you which kind of port you use. You can either bridgeport or streetport. I recommend streetport because your idle won't be jacked up like a bridgeport and you won't need ignition tuning so you can get a SAFC and be done with it.

 

If you're going to be replacing the mufflers and the presilencer just buy the entire RB exhaust and get rid of the stock header\downpipe (sell downpipe!). A true CAI would match nicely for power.

Get a megasquirt and tune the thing properly

I don't think using Renesis rotors will work since they are beveled and will probably need substantial modification to the rest of the shortblock.

Swapping to S5 intake manifolds cannot possibly give you 12rwhp - even on the higher compression S5 blocks it does not give that much power over an S4. I think peak torque on an S5 is within 5ft/lb of S4's.

My 2cents

-Rick

 

The advantage of the s5 intake manifolds is the VDI system... it may not give a top HP number, but it makes a better torque curve. Mazda wouldn't have wasted the money on the system for nothing. My 89 GTU was actually an 88 short block with all S5 intake. I could definately tell a difference when the VDI kicked in.

 

Get a standalone ECU!!!!!!

Spend your money there first, stock ecu blows donkeyballs
-Ben Martin

 

I've seen stock ecu's do it.

I see a therapist now.

 

LOL
Basically all you can do to an NA without opening up the motor is intake, exhaust, and lighter flywheel, and porting the intake manifolds. You can get a fuel controller as well, but I just don't think it worth the money for a stock engine. The money would be better spent on suspention upgrades.
200 hp is the upper limits of a street ported rotary with a fresh rebuild and s5 rotors and intake, plus a standalone and a good tune. Also, carbs are for people that are too lazy/cheap to get a proper efi setup, or for pure race cars. The only time to ever use one is on a bridgeport if you dont want to drop the money on ITB's.

 

well I was figuring if I ever plan to do a street port then I would just do a T2 swap (it will eventually happen either way since I am a turbo nut)

but mainly I am just looking for the best bang for the buck to get as much usable torque and hp's out of the stock n/a motor

instead of the pineapple sleeves I was just thinking of duplicating there shape with the stock sleeves unless they are a tottaly different sleeve in itself.

I will be doing the rb header which looks like that will give me no use for my downpipe now and get a rear RB pre silencer, and then possibly a rb cat back but I may just do mufflers.

suspension is the name of the game as well as rim and tires. so I wont be hard pressed for huge gains in power just traction.

 

I have seen dyno sheets with someone with an Intake, Header and S5 Mani swap that reached just below 200hp. I think he had a SAFC too but I can't remember.

I can't see why you can't hit over 220 with a large street ported motor, CAI, High Flow Exhaust, SAFC and S5 Intake.

S5 intake deffinatly gives you another 10+ hp from 5000 rpm up. Must have been the best mod I have done.

 

what about your gear ratios? your final gears you for 191mph i think, so why not switch your differential for some aceleration?? I think your 5/6 port now is less material than the pinapple insert, im prety sure the inserts are just a curved piece to help flow so i dont think you cAn mod yours simlarly
oherwise it looks like tune your ****, and go as lightweight as possible (mostly reduce your rotaional mass)

 

Miata gears will fit into an NA tranny as well (I think!)

 

my thoughts:

1. open up the 5/6 ports? just buy the pineapple sleeves. you'll end up spending less time and money.

2. you're going to put expensive high performance tires on the skinny vert wheels? buy some wheels you can run 225's or 245's on.

3. get real springs and not just "lowering" springs

4. ceramic pads = awesome, i recommend akebono

5. cross drilled rotors = bullshit, unless it's just for show. machine the stock rotors or buy slotted.

 

Well Im in the same boat heres what Ive done. Got a honda cold air intake and put the cone filter outside the engine compartment for coldest air possible. Stock manifold with custom piping the whole way back into one HUGE fart cannon. The aux ports are wired open, fresh tune up. It might not have much horsepower but I got the car weighing around 2500lbs so it pulls plenty hard for me. Theres not a whole hell of a lot you can do to these motors to get huge numbers. I will hopefully run a drag strip before it closes if it isnt already closed and see what numbers its putting down.

 

vert rims hold 225s, my fronts are 225-50-15, and my rears are 215-60-15, they wwere swapped but yeah i needed to rotate them ?

 

but they're only 6.5 wide... i guess my point is that if you're going for grip, there are better choices to be made.

 

handling:
tires - Racing tires will be best. But if you're worried about tread life and/or wet traction, get Potenzas.
springs & shocks (or coilovers) - stiffer is better but less comfortable; super stiff could even be unsafe on bumpy roads, b/c you could lose traction
DTSS - get eliminators or OEM replacement
I left out bushings, sway bars and strut bars, since you picked some.

Bigger wheels help to a point, you don't want them to be too heavy or it will hurt. Vert rims are nice b/c they are lighter.

Brakes: cross drilled rotors break easier no matter what. Slotting the rotors doesn't hurt them as much. Both methods improve brake cooling. You'll also want high performance brake fluid that can withstand more heat.

 

Transmission Modification Page

I also had a page that had the gear ratios for all the transmissions that you could swap parts from but some how it got wiped out in my last backup / server move. I need to rumage through my disks to find it.

To put the Miata gears in the RX-7 basically you strip the bell housing and tail housing off the miata, put the RX-7 housings on and bolt it in. Of course the TII trannies are a different story but they can be modfied with a B2600i or 929 tranny...

 

I get brake stuff cheap so I will prolly go with slotted or stock..
as for pads I will prolly use akebono or Centric ceramic since I am a dealer for both
I want vert rims for looks and to add a little bigger tire, I will use Falken Azenias (sp)
Ill just buy pineapple sleeves
the lowering springs will be lowering/handling springs (thicker, stiffer and lower)