Ok for you guys in the GSLs running NA what is the top speed you guys run. I am curious because I have my tranny in my B2200 modified with a GSL 5th gear and want to compare speeds.

 

Ive had mine up to 110 in 4th.

~T.J.

 

Do you know what your rpm at that speed was?

 

I hit 112 in 4th and it was about 7500 or so...

high enough that I looked down and went "oh ****, I need to shift"

beleive it or not, at 112 with teh windows down you cannot hear teh buzzer anymore...

My top was about 130mph in 5th though... That's where I ran outta nuts.

edit: crap I read that as GSL-SE, so those numbers won't help you.

 

is the gsl tranny different from the other 12a engined models? i have an 84 gs and i've hit like 115. it pisses me off so bad cause it feels like all power fades in 3rd, 4th, and especially 5th when it gets high in the rpms. :-( think i need a better fuel pump!

-face

 

According to CarTest it's around 128 mph.

 

I was clocked once at 156, but now that I'm more knowledgeable, and realise that the gear ratios just don't add up... (this was 5-6 years ago but still)

However, since then, I buzzed one of those nice radar detectors at 20,60 and 80 to ensure my spedometer was right (it is dead on) and then went out on the freeway and after 127 indicated, slowed down. I'm sure with a full wind, downhill the stock GSL will get really damn close to 140. I just don't plan on being "that guy".

 

FB II: Yes the different models have different gear ratios.

The 83 GSL I used for my mod had a 5th gear ratio of .825:1. After I swapped it into my truck it came out to .835:1. I guess the numbers add up about right, I've had my truck past 110 mph before I lost my nuts and let off the gas, you think 125 is scarry in an RX-7 try 110 in something with the aerodynamics of a brick. The speedometer only goes to 110 and considering b4 I did the mod my top speed was about 90 mph with a redline of 5500 rpm, I did good. Thanks for the info, now I have an idea of what my truck will do with future mods.

 

FWIW I've had mine to 137 corrected and actual MPH. No aero devices on it either. I wouldnt try that in a street 1st gen, they start to lift above 80, and get really light above 100.

 

I have access to long empty(mostly) streches of road. My '85 GSL is stock. At about 6,600 rpm in 5th gear I can get up to an even 130 mph. I can not get any higher rpm in 5th. I only do this a night because it is easier to see another cars tail lights, durring the day a car can disipear in the heat shimmer, and those cars come up fast.

 

110 max, maybe 120 with a good hill or a tail wind?

 

Time out rx7gslse, if you roll the windows down you don't hear the buzzer any more!!!??? Gotta go for a ride now............................

 

I've run it up to 7000 RPM in 5th a few times. I think I worked it out once with a tranny,gear and tire calculator and it came out to 146MPH or something. What's this lift I always hear everyone talking about?? And starting at 80 ? I'm barely out of 3rd gear by then....

I've never felt like the car was lifting or the steering was getting 'floaty' unless it's really windy out in which case I back off...

 

Accorbing to my calculations a gsl in 5th does 21mph per 1000rpm. At 7000rpm you would be doing 147 mph.

In stock condition most gsls would be hard pressed to hit 120mph. I agree with RX7carl that the front end goes light at speed, they really wander in any form of crosswind.

However, the actual speed achieved per 1000rpm will vary according to wheel and tyre size icluding pressure..

 

With the mods you have listed in your sig, it would have taken you a long time to get to that speed, and that means a really long stretch of road. I don't do high speed runs often, but when I do, it gets up to around 130 semi-quick then starts to hit the aerodynamic brick wall and it's slow going from there even at the prime of my rpm band.

Steering gets floaty on mine at around 110 and becomes very apparent how much floating there is when you need to brake right off acceleration at those speeds.

 

I don't know how long it would take to go from 0 to that speed because there was a bunch of us, and I'd say that we'd been cruising at around 5k in 5th gear when we started playing with some top speed runs. It didn't take forever to get to the redline because I'm wasn't comfortable pushing the engine hard above 6k. I don't think I had the under-drive pulley for my water pump at the time and was concerned about cavitation.

The road we were on was an empty highway with a forest dividing both sides that goes straight for miles. It was good times, ahh to be young and dumb again.

George "Slighty older and still slightly dumb"

 

I had my '79 GS up to 175.... km/h but the front end felt like it was going to lift off the ground, and the steering was too sloppy to control the car accurately, so I slowed down.... gotta get some downforce on the front end... haha....


Jeff

 

double post... DAMNIT! #@$#@!!

 

Are you guys using corrected MPH numbers? Or just the speedo reading? It can vary greatly like Paul said, tire (not tyre ) size can make a great difference, along with gearing,trans ratio. My computed 137mph had the speedo pegged beyond 145mph.

 

Rx7carl- my rubber things on 5 of thewheels came marked as tyres, but then the spelling over here is quaint. Rx for example means drug prescription!

 

When you're figuring your theoretical top speed, don't forget that you won't be doing this in a vaccuum. Need to take into consideration your Cd.

 

I'm just messin with you Paul.

lotsacars, when I said corrected mph, it wasnt theoretical. I corrected my actual numbers I got last time out.

 

That's cool. It was just stated above that calculations were done, and at one point the figure 21MPH/1000RPM was thrown out and that will change the faster you're going. It wasn't intended to say anyone was wrong in any particular post, just to point out that air resistance is a factor oft forgotten when sitting behind a calculator. That's all

 

No lotsacars, you made a very valid point. I was just listing my personal experiences. No worries. According to the calculator my theoretical top speed with a stock 3.909 gear is 197mph IIRC yea right that'll happen in a stock port 12A

 

100 is common, 110 is a stretch. Front end starts to feel too light at about 90.

Paul Fitzwarryne: Torquay? My first wife was from Torquay. Don't ask.

B