NewRXr

Ok this is a serious (seriously long winded-lol) question. I've owned a clean SE for about 2 years now. In that time I've gone over this car with a fine tooth comb. I'm a professional mechanic and life long hot rodder who's very good at what I do. Here's the story, about 5 years ago I bought a abandoned '81 12A car for next to nothing just to learn about Rotarys. It supposidly had a blown apex seal but turned out to be severly out of tune and the carb linkage had popped off. With no one to really show me the way I worked on it here and there and eventually figured out with board members help what was wrong. After fixing the linkage the '81 got peppy and fun fast. I thought that was about it, then I rebuilt the carberator and the damn thing got seriously fast. So fast that as a jaded rodder who's other car was a 12 second street car I was really impressed. I would race anyone who would and took it to local street races on ocassion. The little base model would punch out GTP's, Acura's, fast trucks etc. I thought this car was the bomb. The problem was the body was rusty, along with other miscelaineous stuff so when it failed emmissions I decided to upgrade. I found a SE on Ebay right here in town and made a deal to buy. It was a running fixer upper with tuning issues but pretty in and out. So I parted the 12A of the good stuff I'd bought to put on the SE and over the last two years I've tinkered with the car and managed to diagnose and correct what seems almost every problem an SE could have. Now the car starts and drives perfectly. Smooth and powerful acceleration.

Here's my problem. It's not as fast as the 12A car was, close but shouldn't it be faster? I mean it's advertised as a 30 HP increase right? So what gives? Was my beather '81 a ringer? Did it have some porting from it's past life or what? Will a stock '81 in perfect tune run in the low 14's or better? What should a stock SE be capable of?

Should a good running SE be able to smoke the tires from a roll? Mine won't, it just speeds away on the verge of spin.

Guys talk about pulling hard to redline, mine needs to be shifted at or before the buzzer.

What's the top speed? Mine's about 115-120. My '81 only had an 85 MPH speed but I've seen it stay buried long after I pulled my foot off, way long.

I raced a guy in a GN on the freeway once in the 12A and held my own, he won but was seriouly freaking out about how close I was to him. I wouldn't try with this car for fear of embarrasment.

13B's are talked as torque monsters, mines about the same as the 12A with less HP.

You get my drift. Is my SE not good or about right and the 12A was a ringer. I never opened up the 12A so I don't know what the ports were, I always assumed stock.

I've checked everything possible that would explain this lackluster performance and just spent $140 at the dealer for a compression check. Perfect compression 130-145 on all rotors.

Exhaust- runs same with it off
2nd ports working right, had the intake off and checked long ago
AFM- went rich and lean and set to best power
Sensors and injectors- many new or working right
Wiring checked
Ignition and timing- rebuilt, perfected, and checked
Timing- just did the pully marking and advance set trick, worked but still not as fast.
K&N filter- yep

Take my word for it I've tried it. Now I'm thinking that's all there is, am I right?


Thanks,
Vernon

mazdaverx713b

iTrader: (91)

here you go:

IanS

iTrader: (4)

Good info, but you ruined my day... My car isnt much faster, if at all.

85 FB

(minor thread jack, sorry) I've always wondered my top speed. I mean, I've gotten it up to about 100 but stopped because of bad shaking. Just needs balancing and/or new steering linkage (pulls gently to the right anyways).

(back on topic)
Good layout of all that you've done and diagnosed, but I do have one question. Air/Fuel meter. Why may I ask? I mean, as a person of your stature, you should know that an AFM is nothing more than a fancy strobe light and only reads as on or off. Unless, I'm missing something here, but rest assured I have confirmed with many mechanics on how pointless it is to have an AFM. Even my main shop tech, he regrets having one put in and actually doesn't have it hooked up anymore.

But, to still keep this in line with your original question, try some SeaFoam into the gas tank and have it sucked in through the intake (there is a previous thread made about a week ago regarding this, too). And, of course, not doubting what else you have done that may have not been listed in your thread, you could always get one of those G-Force meters that attach to your windshield to measure acceleration and whatnot.

A GSL-SE won't smoke tires, even if you dump the clutch. I've tried a few times and only got a mild bit of squealing while launching, and even a bit of a chirp when going into 2nd. I feel that my car is a torque monster, just by the seat-of-the-pants meter. It maybe just be in your head from switching over from one 7 to the other. You could always get a stopwatch and shadetree-mechanic a 0-60 sprint.

mazdaverx713b

iTrader: (91)

the gsl-se will really squeal the tires but you will have to hold the brake pedal with your left foot in order to smoke em. i have a video that i made if anyone wants to host it i'll send it to them to be hosted.

NewRXr

85 FB, thanks for the comments. On the AFM, I believe your confusing the Air Fuel Meter in the fuel system with an Air Fuel Ratio Gauge. The AFM for the SE and 2nd Gen 7s is that "trap door" electronic device mounted to the filter box. When you open the throttle the engine pulls in air which opens the door against spring pressure. This is a precision instrument (relatively) for measuring airflow. The more the flow the farther the door gets opened. This is the main source of fuel need measurment for the ECM. When I said I adjusted it lean and rich what I mean is that I removed the plastic cover and made adjustments to the spring tension so that less spring meant more door opening and more fuel for a given amount of airflow. This richens the ratio. By tightening the spring tension I did the opposite, applying more pressure to keep the door closed and leaned out the mixture. In the end one step leaner, or tighter, than stock works best for me. I've installed rebuilt parts store injectors also, so that may account for the change. I don't have a A/F ratio guage buy I have used my shop scopes to tap into the O2 sensor signal and monitored ratio. It looks good, slightly rich at WOT.

I think I've done everything you could try to do in the last 2 years, most helped. It took all that to get this one upto par. I used professional 3M injector flush when I did it with the old injectors and as stated my compression is high so it must not have hurt it.

For a more detailed list of some of the stuff I've done, results I've found and problems solved search my handle and look at two in particular "Calling GSL-SE tuners, diagnostic help?" and "Anyone know how to ignition scope a rotary?" I usually come back and post what happened when I take some advice or find the problem I was asking about.


As for the tire smoking burnouts, I see the vids where some of the guys cars just blow the tires off and wanted to ask if this was normal and mine isn't broken. My 12A wouldn't either but it sure had more HP on the top end. Torque was about the same, and according to the posts I've read the 13B is known for more torque. I've come to the conclusion that my 12A was a ringer. I was spoiled by it. LOL But at least I can quit worrying about if there's something wrong with this car. My car will lay good rubber if I drop the clutch at anything above 2000 WOT but I usually don't push it that hard. I'm used to the torque of American Muscle cars so this Japanese corner carver seems wimpy in that regard but it's probably fine. Like I said it makes light tire squeal through most of 1st, will scratch 2nd with ease and sometimes chirps third. I'll just work on improving that.

I try to help others when I can but this board is so busy that there's usually 5 good answers to every post I can help on.

Cheers,
Vernon

Nicholas P.

iTrader: (1)

your engine could have been ported. It makes a big difference. gas milege suck? : ).

I gurantee you that 12A is ported. rebuilt that carb and made it wicked fast. oh yeah!. : )

I have a 12A and I would never trade it in for a 13B. classic carb. mmmm. I hate fuel injected.

-Nick-

steve84GS TII

Ive driven a couple stock SE's and while they are smooth and tractable,I found them to be a bit boring.
The torque curve is so flat and long that there really isnt any punch to them.Granted,you can bog them down and work the lower range without any complaints from the engine.But in a straight line,drag race type situation,it seems more like an electric motor than a rotary,just flat linear power.This of course is what automakers like,and Im sure Mazda was shooting for this after years of people saying,"Rotaries have no lowend torque".

Regardless of what your used to or are expecting,the SE engine will benefit greatly from some of the same mods that make the 12A a hoot to drive.All 3 of these systems are basically the same as on the 12A,and all 3 are PROVEN to allow very large gains in performance compared to stock....
1st...Ignition.....its no different than the 12A,get a 3rd coil and an MSD6A box and direct fire the leading ignition.The engine will love you,youl be rid of the scetchy leading ignitor,and youll be virtually copying the stock 2nd gen ignition system.

2nd....Exhaust....get a header and free flow catylist.Even if you have to smog,it WILL pass a sniffer test like this,just retain the air injection system and the 6 port actuator tube.Its not legal in CA technically(visually),but its easy to switch back.Even with the stock muffler,you should see some gains from the tuned header and improved,modern cat design.An aftermarket muffler will help,but few other than RB are quiet.

3rd...Light flywheel....the SE's flywheel is heavy and keeps it from revving free.Most of the torque is thanks to the small primary ports and the tuned intake system.If you free up the revs by removing some rotating mass with a 14lb or 11lb flywheel,the engine will be much more responsive in the lower gears and should still be plenty easy to drive.Its my favorite mod and Ive done it to all my rotaries with no downsides.Youll re-learn the clutching characteristics in a day or two.

RacerX7fb

My triple- overheated SE puts down a sorry 106RWHP but can still lay down a twin patch of rubber

EL5Letra

ive smoked more than my tires with my gsl-se...a 1st gen is a not force to be reckoned with . BHWHBHAHAHAHAhAhAH

novaboy009

My bone stock 99k mile GS will light up the fresh cheapie Cooper tires.

It will not, however, lay tire at will in any gear, do 45 second stationary burnouts or pull the front wheels 8 inches off the ground like my other car

Kev

bmwjdmking

lol i need some new tires now that you mentioned it.

clean85owner

I have a carb'd 13B, wanna run?

Roundabout

iTrader: (8)

Just thought I would chime in... this website has a huge list of cars with their stock times (including a lot of the rx-series)...not sure how accurate it all is, but it seems legit.
Enjoy!
http://www.albeedigital.com/supercou...0-60times.html

PS My 12a with an open differential (with mods listed below) will burn the tires off the rims while just feathering the throttle, even with a passenger. I can bark them real good when shifting into 2nd gear too. Shes very peppy for a 12a stockport.