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-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   Top Speed Problems (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/top-speed-problems-293247/)

scheistermeister 04-11-04 02:29 AM

what gives?!
 
so i got a chance to max out my car on a straight road...
the thing maxed out at 110mph... what gives?! my civic went faster than that!

anyone know a few reasons this could be? it an 87 SE

NZConvertible 04-11-04 03:06 AM

Dirty air fliter, clogged cats, low compression, non-functional 6PI, etc, etc.

I believe stock S4 NA's topped out at ~120mph, and you need ~30% more power to get from 110mph to 120mph so something's obviously amiss.

Have you changed wheels/tyres, gearbox or diff? If you have you might have thrown the speedo out.

Bigretardhead 04-11-04 03:46 AM

when I first got my 2nd N/A, I went 120mph no prob. then, I changed the wheels/tires to some that were a bit wider, and stuck out a little. then, I could barely get up to 100mph, and lost a race to a friends jeep :D but the cornering was amazing!!!

wheels/tires can make a HUGE difference, even if the size is the same.

scheistermeister 04-11-04 01:34 PM

i have the stock wheels, but could prolly use better tires (have cheapies on there now). i just changed the plugs on it about 100 miles ago and oil. had a single cheapy muffler put on with a 2.5 inch pipe from cat-back. whats the 6PI and how do i check whether its working or not? sorry but i had miss posted when i said 110.. it was 102mph.

scheistermeister 04-11-04 01:36 PM

oh yeah i need new shocks too... would that make that big of a difference at top speed?

Rxmfn7 04-11-04 01:41 PM

I believe the posted top speed for a stock N/A is 137MPH. If you cant get yours going past 110..something is definately wrong. Ive found myself going faster than that by accident :p: Do a compression test, and varify that the auxillary ports are opening.

NZConvertible 04-11-04 06:31 PM


Originally posted by Rxmfn7
I believe the posted top speed for a stock N/A is 137MPH.
Ah, no. A TII can't do much better than that.

scheistermeister 04-11-04 06:43 PM

ok i did another run today and it is 110mph... the guage gets there and twitches slightly, seams like its trying to go faster but cant.

yeah i read the top speed was 137mph... thats why i think something is wrong.

how do i check the auxillary ports?

sEeMiNhThEdEmOn 04-11-04 07:06 PM


Originally posted by NZConvertible
Ah, no. A TII can't do much better than that.
uhhh.. i hit 130-135 racing a 350z (speedo read 140) but im sure its that inaccurate when it gets that fast.

oh btw its a '89 n/a

BDoty311 04-11-04 07:19 PM

Yes, I have heard and read many people hitting the 130s stock or nearly stock. Probably takes awhile, but the aerodynamics really let the car get up there.

scheistermeister 04-12-04 02:15 PM

hey, how fast should i be going when i hit 7000rpm in 4th gear?

Rxmfn7 04-12-04 02:21 PM


Originally posted by scheistermeister
hey, how fast should i be going when i hit 7000rpm in 4th gear?
In a 5-speed N/A with 4.10 rear end, about 120MPH.

SwooshMan 04-12-04 02:34 PM

Wouldn't altitude have a bit to do with it?

gambone 04-12-04 02:38 PM

OK kids we need more info, like rpms, tire size, final gears. Something to think about, my 76 RX4 had 3.65 rear end and getting to 110 was easy and had lots of gas peddle left, going faster was ass dum, handling was poor and so where the brakes. now it has 2nd gen suspension with 4.1 rear and a lot more power and gets there real fast but it takes all most all of the RPMs to get to that same speed, so do some math

MazdaRx7Racer4Life 04-12-04 02:42 PM

Im not sure about altitude, soince I was at sea level, but when I used to own my NA I topped the thing out at 136, I had 16 inch wheels with 245 in the back and 225's in the front, it took me like 2 minutes to squeeze my last 15 mph out of it, ofcourse I then got pulled over and the cop just started laughing at how crazy I was and let me off with a warning, he clocked me at 136, my speedo was going insane, it said more but I knew it was wrong. A REALLY nice guy, he said that I was lucky no one was around and not to do it again. (cuban cop, lol)

nashman69g 04-12-04 05:08 PM

I've gotten to 127mph and that was all I had !!

RETed 04-12-04 05:16 PM

Don't shift into 5th and bury the tach in 4th gear...


-Ted

fc3sdrifting 04-12-04 05:17 PM

i got my dads 4 door 105hp civic to 116mph.

1987RX7guy 04-12-04 05:26 PM


Originally posted by NZConvertible
Ah, no. A TII can't do much better than that.

I have seen a video of the FC against the porsche and the guy got it up to 130 in 5th and they were video taping it. Granted the car is no longer new it should be able to hit atleast 120.

WolfsRx7 04-12-04 05:48 PM

I've done 130mph in my 90 GTU going down I-10 course the alignment was off so I couldn't see out any of the mirrors lol it was so much fun.

Relisys190 04-12-04 06:15 PM

135-140 tops... factory sized tires and "vert" BBS rims

-Markus (Devoted Rotor)

fc3sdrifting 04-12-04 07:38 PM


Originally posted by 1987RX7guy
I have seen a video of the FC against the porsche and the guy got it up to 130 in 5th and they were video taping it. Granted the car is no longer new it should be able to hit atleast 120.
i think your talking about the top gear video. it was an 85 fc n/a 2+2 and they were testing it with the porsche 944

PsYcLo 04-12-04 09:20 PM

Ive irked out just over 125 with 2 people and subs.

BDoty311 04-12-04 09:55 PM

Top speed is determined by a few factors mostly.

1. Power, more power, the faster you will go
2. Aerodynamics, makes the applied power get you farther
3. Gearing, helps you apply the power the best

Thats basically it. Weight alot more to do with acceleration than top speed.

red_ricer 04-12-04 10:06 PM

i dont know about you guys but if i was going anything around a 100 or more i would be more concerned with the road than looking at my speedometer. Also got a joke for ya.....What is the difference between going 100mph and 120mph other than the speed? the answer is open and closed casket.


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