I was crusin in my rx tonight and so i decide to take some back roads i know and run pretty fast, until i hit about 100mph that is...it just wouldnt go any faster. so i slow down, try again, no faster. i was redlining 4th and as soon as i hit 5th, nothing... how frustrating... i have done some searching on this subject and found maybe a few with the same problems, but no fix. i have an 88na with no cats and the aux ports wired open. i think the latter may be the problem(from what ive read) but how would that be fixxable? any input as always will be greatly appreciated.

 

You should fix your auxilary ports first of all. But that probably isn't your problem. if you stay in 5th your never going to get past 100 on a small stretch of road. keep it in 4th and you should get around 125-130MPH out of that gear. 5th is just too tall for any road lol.

 

I hit 144 in my 88 n/a. then I had to slow down so I wouldn't die. bone stock. That was the second day I owned it. I haven't tried for top speed since I have made all of the mods. but it isn't for top speed. it's for turns. I guess I should try again just to see.

 

If your car has been imported from japan then it will have a speed limiter at 180 km which is about 110 mph give or take.

 

when you say iported do you mean the whole car or just the tranny/engine.......i know there are many Factors that contribute to top speed. i have an imported jap motor and tranny both T2. but the rest is us.

 

dam you guys got your fc's up that high? man in my 87 n/a with intake , exauhst plugs and wires all i could get was 115 ( thats all i could get stock too) i even hit the nitrous towards the top of 4th gear around 4-5k and the engine didnt like that too much . but still all i could get is 115. now i wanna take the gxl out and see what i can hit in that

 

ive gone 155 in 5th at 7100 but people tend to think that the speedo isnt that accurate at those speeds so im just going from what the speedo said.

 

Well as far as I know all FC's in the USA came from japan so your wrong on that one buddy. I did 135 in mine. I have also done 120 often(once a month maybe) so unless your talking about AUTO's that would be a NO.


We have a rev limiter but no governer that I know of.

 

Accourding to my mechanic if you got the ecu from a convertable, your top speed should be around 115 and if you got the stock one that comes on a none convertable you should max out at 145 max and that pushing every gear to redline(7,300rmp) ...i've gotten my my 1st gear to 35, 2nd to 60, 3rd 85, 4th to 125,and then i slow down because my car starts vibrating and i cant control it .....its scary.... i think i need an alignment ............. when i get the alignment i expect to reach 135 to 145

so pretty much i've gotten to 125 mph in 4th gear and all i have is intake ,a rebuilt engine and racing beat headers ,2.5 exhust and yeah the spec 91 spec engine modification

 

Damn guys, be careful doing high end checks...

I had a client about kill me when he lost control of his 95 Corvette and we smashed through a telephone pole...

Have fun but be careful...

 

all i know is that if i redline every gear, as soon as i hit 5th the tach goes back to 4k and i slow to about 100. no matter how much gas i give it, it wont go past. im going to see if there is a way to rig up my aux ports so they will work correctly without having to wire them open. the only problem is that when the front rotor's aux port actuator was being re-installed, one of the bolts just twisted right off, didnt even get tight. so i dunnno....

 

If you have an N/a how the **** do you have a J-spec engine? All J-specs are Turbo. And I have heard of verts doing well over 115 on stock ECU. Like I have said I have never heard of a GOVERNER. There is deffinately something wrong with your mechanic unless he can proove that info is correct.

 

I had an 86 na, had it not even redlined in 5th going 140+

... oh yeah and this thing was a POS it was my first car, 175k miles, I beat the **** out of it.

 

Dude... If you din't know the 1991 rx7 n/a did come to america and i din't say i had a j-spec engine ...i said that i have the 91 engine spec or let me re-phrase it "i have the 91 configuration"...which means that the engine has an output of 160 hp stock instead of the 148 hp that came in the 87 n/a rx7...and i din't say that all conv can't go past 115 ,i said that "Accourding to my mechanic if you got the ecu from a convertable, your top speed ......should be ....around 115" in other words' it can go higher but i don't know by how much .because accourding to my mechanic the ecu's of the conv and the none conv are different .and in addition i know for a fact that the ecu controls rev limit and top speed of the car ...thats why if buy a new programable computer you can change the setting of top speed, and rev limet,boost, (on automatic gear change point) and a heck load of other stuff on the car (((i know..this because i was there when my mechanic install a new programable computer on his car......))))

 

woops I saw J instead of 91. :-/

But we do not have a rev limiter. We have FUEL CUT which is at 8500RPMs IIRC With all the gearing worked out mathmatically the top speed is well over 150mph but the N/a's don't have the kind of powere to take us up there stock.

 

i've redline all the way to 4th gear and reached 125 and i have never seen anything happen like in cars with govs

 

lol .....yeah that part i know ...because it came on..............on me at the track ...when i was doing the warm up burn out ... i thought i blew my engine ...when that happened ..but then it work just fine ....and i was like ...am so lucky lol

my tach went off the numbers

 

none of the north american FC's have a speed governor.

the ones in japan did.

all the FC's have rev limiters. 7800 on all S4's and all turbos. 8800 on S5 N/A's (maybe 7800 on auto's?)

weither or not they still work on each car is another question.

 

Why would fcs from japan have a speed governor but not in america? Isnt it logical to think it would be the other way around?

 

When I owned my 88 n/a (stock)I redlined it in 4th at 135 mph. When I shifted into 5th it didnt gain anything but it didnt loose anything either. Whats up with that? I know what you guys are talking about with the fuel cut. When I first bought the 7 I took it on a "spirited" run at one point the entire car felt like it just died. I swallowed my heart that day. Started right back up though. How can you not love the wankel. Pistons suck

 

Your mechanic is smoking something, and you should not be taking your car to him anymore, for he is clueless.

There are plenty of stock USA spec 'verts that have hit 125. Heck even Road & Track hit 124 in 5th gear on a 88 'vert when testing it brand new, back in 88. That would be 10 MPH more than your limit, that you claim.

The 88 vert ECU is basically a T2 ECU, and will run a 13BT just fine if wire correctly to one. Run a 'vert up to 135-140 just fine. I know this because I have done it. Mazda used a T2 ECU for better gas mileage in the map.

Furthermore, the US spec ECU's do not have a speed sensor input to even know what speed the car is going.

And the Auto Tranny computer is not even the same box as the ECU. It is a standalone part, so you can't reprogram the ECU and have it change the auto tranny computer. If your mechanic told you that he did, he is lieing to you. You would have to reprogram the auto tranny computer, not the engine computer to change the shift points. Or he has some Honda or Toyota or something, but not a FC.

Now JSpec ECUs and cars have a 112 MPH limit as mandated by the Japanese government... but that did not ever come to North America.

Get off the pipe.

 

The 87 N/A came with 146 HP, not 148.

 

I've hit 135, and that was at like 6500. I got kinda scared , and was runnin outta road.

 

think im looking at the wrong car to replace my fiat if they wont go above 135mph!!!!
i tend to hit 140mph every other day and 150mph+ every week!!! admittadly its a bit easier to do it here in england than in the states!
beast i have had from my car is 167mph but that was calculated as the clock stopped at 160mph!call it 155mph+ if allowing for speedo error


beast

 

how does the FC feel at such high speeds? does it feel like your really dissconnected from the road? like car car is starting to lift off the ground? iv only done about a dollar five in mine.