7000rpm
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Junior Member
Joined: Jan 2014
Posts: 98
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From: detroit
Car: 84 z
Engine: 350
Transmission: 700
Axle/Gears: auto overdrive
7000rpm
After being patient for months now I finally stomped the pedal to the floor and held. Well broke in 290hp crate with rebuilt 700R4 .The tach flew up to 7000 then shifted to second. Both remaining shifts were at 5000. What do you think. back to the trans shop? Thanks
Joined: Feb 2017
Posts: 4,174
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From: Meriden, CT 06451
Car: 84 TA orig. 305 LG4 "H" E4ME
Engine: 334 SBC - stroked 305 M4ME Q-Jet
Transmission: upgraded 700R4 3200 stall
Axle/Gears: 10bolt 4.10 Posi w Lakewood TA Bars
Re: 7000rpm
OK, I'll start this.
Is your TV cable hooked up and properly adjusted?
Quadrajet carb or something else?
Is your TV cable hooked up and properly adjusted?
Quadrajet carb or something else?
Thread Starter
Junior Member
Joined: Jan 2014
Posts: 98
Likes: 4
From: detroit
Car: 84 z
Engine: 350
Transmission: 700
Axle/Gears: auto overdrive
Re: 7000rpm
No PC on this car. New Rochester 4brl.w/ new tv cable as set by trans rebuilder Still under warrantee. Should take it back to him when over this flu.....thanks for your reply.
Thread Starter
Junior Member
Joined: Jan 2014
Posts: 98
Likes: 4
From: detroit
Car: 84 z
Engine: 350
Transmission: 700
Axle/Gears: auto overdrive
Re: 7000rpm
Yes original tach. Fast idle around 1500 curb idle 650-700rpm. whatever the Latin I well return the car to the trans shop for inspection. Thanks again
Joined: Sep 2005
Posts: 27,874
Likes: 2,431
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 7000rpm
I thought so.
Sounds like your tach reads around 50% higher than reality, more or less. Maybe a bit more than 50% high but who knows. Basically just like everybody else's does, sooner or later.
I.e. when it reads 1500, the REAL engine speed is 1000; when it reads 3000, the engine is REALLY doing 2000; when it reads 6000, REALITY is 4000; and so forth.
Which ultimately means, you don't have a transmission problem; you have a "tach" (I use the word loosely) problem.
Hook up a piece of actual test equipment to it and compare.
Sounds like your tach reads around 50% higher than reality, more or less. Maybe a bit more than 50% high but who knows. Basically just like everybody else's does, sooner or later.
I.e. when it reads 1500, the REAL engine speed is 1000; when it reads 3000, the engine is REALLY doing 2000; when it reads 6000, REALITY is 4000; and so forth.
Which ultimately means, you don't have a transmission problem; you have a "tach" (I use the word loosely) problem.
Hook up a piece of actual test equipment to it and compare.
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From: Freehold NJ
Car: 87 Iroc 5.7,67 SS Camaro,90 Formula
Engine: 355 AFR Superram LPE 219
Transmission: 700r4 3000 stall 4spd 5 spd
Axle/Gears: 3.27
Re: 7000rpm
My reading on my stock tach to my autometer varies anywhere to 200 to 500 rpm.
Joined: Sep 2005
Posts: 27,874
Likes: 2,431
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 7000rpm
Then yours is unusually accurate.
Most are off by a percentage, a multiplier; NOT a fixed "additive" amount. That is, they follow the discipline I described above. If the indication was off by some fixed error at all RPMs, all you'd have to do to fix it, is pull off the pointer and put it back on at a slightly different angle. However that's not how it generally works.
I have (or had? might have trashed it) one of these things that's off by a factor of almost 3
... at 1000 REAL it shows 3000, at 2000 REAL it shows 6000, and so forth. The one in my car now is the best one of all that I had at the time, it was only about 5% high.
Most are off by a percentage, a multiplier; NOT a fixed "additive" amount. That is, they follow the discipline I described above. If the indication was off by some fixed error at all RPMs, all you'd have to do to fix it, is pull off the pointer and put it back on at a slightly different angle. However that's not how it generally works.
I have (or had? might have trashed it) one of these things that's off by a factor of almost 3
... at 1000 REAL it shows 3000, at 2000 REAL it shows 6000, and so forth. The one in my car now is the best one of all that I had at the time, it was only about 5% high. 
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