driftin8ez

I picked up a 91 N/A RX7 about a month and a half ago and since then i have done the following to try and get my car up to atleast stock speed.

New fuel filter
New air filter clamped to the end of a dangling afm
Ground wire kit
new NGK plugs/ wires
New o2 sensor
Got a straight pipe from the cats to the y pipe to stock mufflers
No acv. -have a fitting on the end of the airpump hose to block some flow and pressurize the hose then i have 2 elbows coming out with vacum lines going to the 6port and vdi soleniods.
water treatment
replaced all belts
removed ac and ps
light weight reduction
It also has a tII flywheel, clutch, tranny, driveshaft, lsd off an s4.
Changed all the fluids on the entire car. redline in tranny and lsd

Basically the prob. is my car wont rev past 6000 willingly. It revs ok with no hesitation till 6000 then it just dies. Sometimes it will go past but not often. also the rear aux. port sticks open so i cant go past 3850 unless i want to get out of the car at a stop light and close the port by hand. So what the heck is wrong. Car idles anywhere from 700-1000 after it is completly warm. Before that it will idles at 2k then when it gets a little warmer it will bounces from 1400-1600 then after i drive it up to opp. temp it will idle at like 700-1000. why does my n/a suck so bad? i was reading that beefy n/a post and was thinking to my self wow i would be lucky to run a high 16 at the track.

Mason Rx7

Holy crap you own my car. Check sig...

I'm having exactly the same problems.

Can you redline it without a load? My redlines just fine without a load but driving in gear I can't hit redline and my car dies at about the same time.

driftin8ez

ya i can redline it in neutral. Dont really make a habbit of that though. You cant rev past 6k? wtf... should we look into a TII fuel pump. maybe we are running lean at high rpm. I might completely remove my aux. ports as some say it is much better.

Mason Rx7

This winter I'm going to be tearing into the intake/exhaust stuff and cleaning it all out.

I have a strong feeling that is a combonation of 5th/6th ports and VDI not working. I'm planning on running those off a electric airpump.

I don't think that it is leaning out cause I get a good backfire usually when I let off. And putting a TII fuel pump in isn't really fixing the problem, it would still be broke. I am having my injectors cleaned this winter too.

The timing could be seriously off. I havn't looked into that yet.

Mine isn't exactly 6k. It is more like 6.7k before it kicks out but the power drops right after 6k.

driftin8ez

true i havn't really set my timing with a gun either. i get a good backfire aswell. im sure my aux. ports are working becouse like i said one gets stuck open. As for the vdi there is no way of me knowing. I know they are bot plumbed the same so i see no reason why it shouldn't work. I also checked it out by putting compressed are to it when the car is off. I get a loud knock with like 10psi on the tube. Did you ever to that? what sound did it make. Maybe the actuator for the vdi is broken and not actually touching the vdi runner itself.

SonicRaT

iTrader: (6)

Good luck with that RE swap...

IaMtHeRuThLeSs1

Mine does the same thing you guys are describing

I'm 95% sure its the VDI, look it up in the FSM.

I looked it up a couple of weeks ago with plans to fix it...but I really dont have that much time to have down time on my car...so I'm stuck reving to 6200rpm all the time

driftin8ez

you doubt my abilities? just becouse im a noob to these rotary engines doesn't mean im a noob to engine swaps, suspension tuning, and reading a book(fsm). just need a little help. im sure you needing a little guidance here and there. and about the RE swap. well isn't it a good thing i made that post now and not after im already 2500 into the swap. And btw im confident i can still do the swap its not that hard.

driftin8ez

ya me to but ive tried to hook it up several diff. ways with the same net result. I think im going to pull my aux. ports and close up the holes. Maybe ill order some pinneapple sleeves for christmas and give that a shot.

speed_monkey

Isnt the TII flyhweel the heaviest one? Why would you run that? Get an aluminum from RB.

driftin8ez

i thought that maybe all the tII stuff was slowing me down becouse it was beefier and beefier for stock heavier. but would it cause my car not accel. past 6.5k.

speed_monkey

Also, a filter just stuck on the afm will make you LOSE power. You have to have a way to seal it from the engine bay and a way to draw in plenty of cold air. The stock snorkel does a better job than you think.

The big restriction is the afm itself. Get a megasquirt, take off the afm, build a good intake and call it a day.

Mason Rx7

I'm planning on getting the Pineapple Sleeves when I tear it apart. Hopefully I will be able to fix it and upgrade it. My car will feel sooooo much faster. Haha!


The TII stuff wouldn't slow it down that much. Mine was doing this when I still had the N/A drivetrain. Now I have a lighter flywheel and it doesn't make a difference.

driftin8ez

ok ya. what i was just going out to do was switch the plugs for the vdi and aux.port. That way i know my vdi is coming on all be it a bit early.

speed_monkey

A lighter flywheel doesnt make a difference? Ha! It's quite possibly the best thing you can do for a n/a. What flywheel did you buy? It's not all just the weight, but where the weight is.

Also, pineapple sleeves dont really do much, save your money for something better.

eriksseven

iTrader: (6)

Check timing and TPS. Both can significantly effect drivability.

Mason Rx7

12.5lb ACT flywheel. I didn't mean to say that it didn't help at all. I meant that it didn't help my problem at all. Sorry for the misunderstanding.

I've also heard the Pineapple Sleeves are really good. It is just $50 too. Might as well while I have it apart.

Dom_C

I've got my money on a few things. .Idle is funny because there's a vaccum leak somewhere, wont rev because the 5th/6th ports and the VDI arn't opening properly. Just to test, I would wire all three of them open and take her for a ride. . You will notice a loss in low rpm torque but you'll love the top end

alexdimen

iTrader: (13)

does it stutter or miss at all?... you really think it's an A/F problem? so when your port sticks "open" does that mean that it sticks in the position that allows air to flow? that wouldn't change high rpm performance.

as far as the sleeve inserts, i'm running them... i never had an rx-7 without them though, so i can't even tell if they work haha. just be sure to secure them well with a set screw or something better than just adhesive... some people have had problems with them coming loose.

Dinnercoat

Best thing? Wouldn't a lighter flywheel on a relatively unmodded NA simply gut what little torque there is to begin with?

And I've seen these mentioned but what are pineapple sleeves exactly?

alexdimen

iTrader: (13)

they fit into the 5th and 6th port sleeves , creating a gradual bend/flow into the combustion chamber. it's essential porting your 5th and 6th intake ports for less turbulence from what i understand. it certainly can't hurt unless they're not properly installed.

i've heard arguments that air/fuel will create it's own path of least resistance, but i fail to see how a turbulent path with sharp angles and bends is more efficient than a smooth and gradual one. i wonder if anyone has dyno'd the sleeve inserts before and after... getting off topic

Mason Rx7

My thought was a vaccum leak as well. My idle will sometimes sit perfect. It is kinda weird. I think the BAC might need cleaned or replaced as well. I have some time tomorrow and I think I will wire them open and take it for a test drive to see if it helps at all. I have no idea how to wire open the VDI though.

According to Pineapple Racing the Rx-8 is now using something like them. Just food for thought.

2RotorRacing

you might wanna check your vacuum lines and hoses...all of them .....or maybe your 5th and 6th port.......the 5th and6th port normaly lag at 4500 rpm but i could be wrong on all of this...

driftin8ez

Ive been looking for a rats nest removal for an s5 na and haven't found one. im just going to rip out the aux. ports and block them off. Im going to do a turbo swap anyway as sonicrat pointed and i cant really be bothered any more. SO then i just have to worry about my vdi working properly.