147 MPH - Won't go any faster?
Registered User
Joined: Jul 2001
Posts: 4,577
From: DeKalb, IL
Re: 147 MPH - Won't go any faster?
Originally Posted by speed_demon24
That doesn't take into account the convertor slippage though...
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: 147 MPH - Won't go any faster?
Madwolf is right. When i said 5800, i meant 5800 on the tach and including slippage. So my shift from 3rd to 4th (on stock programming) was at 125mph at what appeared to my naked eye to be 5800 
Registered User
Joined: Nov 1998
Posts: 746
From: Columbia, SC, USA
Re: 147 MPH - Won't go any faster?
Originally Posted by 30696bird
Here's a worthless reply but....................you're a MORON! You will kill you or even worse someone else at thos speeds. Get some REAL mods and go to a track!
Registered User
Joined: Oct 1999
Posts: 1,490
From: Tampa Florida
Re: 147 MPH - Won't go any faster?
Yeh ive done the top speed run... when the car was stock.. I hit about 148mph before i let off because i could the driveshaft shaking..
Anyways waht u need to do is mod the hell out of your car and put big brakes on it... so u can get it up to speed like a bat out of hell and then back down... so u can get that **** out of your system...
works for me
Anyways waht u need to do is mod the hell out of your car and put big brakes on it... so u can get it up to speed like a bat out of hell and then back down... so u can get that **** out of your system...
works for me
Registered User
Joined: Mar 2004
Posts: 246
From: Bordentown NJ
Re: 147 MPH - Won't go any faster?
One deer in the road and its all over...you wont be lucky enought to pick deer guts out of your car, they will be sifting through trying to figure our which bones are the animals and which ones are yours!
Registered User
Joined: Feb 2001
Posts: 1,234
From: New Bern, NC USA
Re: 147 MPH - Won't go any faster?
You guys bashing him need to lay off. He didn't say where he was doing this. Maybe it was a public highway, maybe it wasn't. If there is anyone here not guilty of breaking the law, you still can't throw stones. You don't know the story.
On to the point of the post. Madwolf, where can I go to use the calculator you used to find top speed? Or could you plug in my info?
91 RS, lowered, 3.42s, T56, 456 rwhp.
On to the point of the post. Madwolf, where can I go to use the calculator you used to find top speed? Or could you plug in my info?
91 RS, lowered, 3.42s, T56, 456 rwhp.
Registered User
Joined: Jul 2001
Posts: 4,577
From: DeKalb, IL
Re: 147 MPH - Won't go any faster?
I use cartest. I know many people will say it's not very accurate, but it has been accurate enough for me. You can get it here. Scroll down to the bottom of the page where it says download cartest 4.5 here.
This program runs in DOS by the way.
You will need to start with a stock car (for example 1992 z28) make a copy of it and input your own data, then test. (the HP values are flywheel, so yours will be 530 HP / 514 TQ, etc)
This program runs in DOS by the way.
You will need to start with a stock car (for example 1992 z28) make a copy of it and input your own data, then test. (the HP values are flywheel, so yours will be 530 HP / 514 TQ, etc)
Last edited by madwolf; Apr 12, 2005 at 09:38 AM.
Registered User
Joined: Jan 2001
Posts: 2,905
From: Orlando,Fl
Re: 147 MPH - Won't go any faster?
Originally Posted by Eck
Not that it really matters, I'm just curious as to why this is happening? So I took my car out for another top speed run the other day in an attempt to break my previous record of 147 MPH which was done with only Hypertech programming and a Flowmaster muffler.
So it went like this. I got up to speed, hit 147 again doing 5800 RPMs in 3rd gear. It took forever to shift -- it just stayed at 5800 RPMs for like 3 seconds straight. Finally it shifted, now doing 4000RPMs in 4th gear, still doing a steady 147 MPH, with the gas pedal still to the floor. It won't budge any further.
I know the car isn't lacking power to accelerate, it was doing fine until it got to that point. Well at least the HP is still high in 3rd gear at that RPM and my TQ is still very high in 4th gear at that speed. I have the top speed limiter disabled. This makes me wonder is there some sort of global speed limiter that cannot be overridden for 93-97 cars? What else could be causing it to stop accelerating?
Once again, not that this is a major concern as I'll probably never drive that fast again, but rather I'm just curious.
So it went like this. I got up to speed, hit 147 again doing 5800 RPMs in 3rd gear. It took forever to shift -- it just stayed at 5800 RPMs for like 3 seconds straight. Finally it shifted, now doing 4000RPMs in 4th gear, still doing a steady 147 MPH, with the gas pedal still to the floor. It won't budge any further.
I know the car isn't lacking power to accelerate, it was doing fine until it got to that point. Well at least the HP is still high in 3rd gear at that RPM and my TQ is still very high in 4th gear at that speed. I have the top speed limiter disabled. This makes me wonder is there some sort of global speed limiter that cannot be overridden for 93-97 cars? What else could be causing it to stop accelerating?
Once again, not that this is a major concern as I'll probably never drive that fast again, but rather I'm just curious.
I am going to have to say that your tranny is on it's way out. This happened to my car before, then a while later the tranny went. Got it rebuilt and went for another top speed run and pegged the needle.
Thread Starter
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Joined: Dec 2003
Posts: 180
Re: 147 MPH - Won't go any faster?
Originally Posted by med_reject
5800 on the tach in third, with 2.73 gears works out to 147mph with my calculations, cuz third gear was at 125mph at 5800rpm in my a4 with 3.23 gears (try working it out). Your speedo is not off, you simply can't pull overdrive with 2.73 gears at those speeds, not with a stock lt1.
Also, to everyone else who says "omfg, ur a moron!@#!!!" and the like, lay off. I didn't post to have anyone come here and criticize me for testing out my car a couple times, just like many others do. And for those who were wondering, I tested it on a desolate turnpike, which is basically a 75MPH toll highway. No one was around, there were walls on both sides -- no fear of deer or anything else. It was pretty much a straight race track if you ask me.
Thread Starter
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Joined: Dec 2003
Posts: 180
Re: 147 MPH - Won't go any faster?
Originally Posted by '94 Bad A Z28
I am going to have to say that your tranny is on it's way out. This happened to my car before, then a while later the tranny went. Got it rebuilt and went for another top speed run and pegged the needle.
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Joined: May 2004
Posts: 467
Re: 147 MPH - Won't go any faster?
He said not that it really matters. There is always someone who tries to pretend like they are more sensible drivers than others.
By the way he made no mention of doing this on public roads.
Anyone driving faster than you is a moron, and anyone driving slower than you is an idiot.
- Z28WannaB
By the way he made no mention of doing this on public roads.
Anyone driving faster than you is a moron, and anyone driving slower than you is an idiot.
- Z28WannaB
Originally Posted by stereomandan
Sorry, I miss the point of seeing what your top speed is. Are you racing on the salt flats, or an oval track that supports those speeds? Unless you have a death wish, is there really a reason to check?
Dan
Dan
Thread Starter
Registered User
Joined: Dec 2003
Posts: 180
Re: 147 MPH - Won't go any faster?
Originally Posted by Z28WannaB
He said not that it really matters. There is always someone who tries to pretend like they are more sensible drivers than others.
By the way he made no mention of doing this on public roads.
Anyone driving faster than you is a moron, and anyone driving slower than you is an idiot.
- Z28WannaB
By the way he made no mention of doing this on public roads.
Anyone driving faster than you is a moron, and anyone driving slower than you is an idiot.
- Z28WannaB
Originally Posted by Eck
Once again, not that this is a major concern as I'll probably never drive that fast again, but rather I'm just curious.
Registered User
Joined: Sep 2003
Posts: 627
From: Edmonton, AB, Canada
Re: 147 MPH - Won't go any faster?
Unless you have nitrous or forced induction, you wont pull 4th gear effectively with 2.73 gears. Even a cam would shift the rpm at which peak torque occurs with insufficient change of max flywheel torque to achieve the potential top speed. Get 3.23s and you should be able to hit 165mph, at around 5300 on the tach, which will be right at your power peak. You'd get more acceleration with 3.73s, but you'd over-rev in 4th (hurting top speed) unless you change the cam to shift your power peak accordingly.
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Joined: Apr 2004
Posts: 1,046
From: Fargo, ND
Re: 147 MPH - Won't go any faster?
figured i would chime in on this one. wheni first got my car i felt like dong a top speed run and it wouldnt go over 140. it would get to about 135 and then the needle would barley budge from there. did it like 3 times on different occasions, and just thought that, that was as fast as my car was. oh well. then i ran someone else and he was a car back the entire time. and he was doin 153, i let out first. so at that point i realized my speedo was out. or atleast not to accurate to say the least. since then i havent done over 90, lol.