91 Camaro runs great but it wont go pass 75
In the Staging Lanes
Joined: Jul 2009
Posts: 36
From: Tennessee
Well still find out what gears are in your car now and if the problem is the gear ratio. But, i would check craigslist. That's where i bought mine and mine was a 4th gen rear axle and was in great shape, i paid 150 for it.
In the Staging Lanes
Joined: Nov 2009
Posts: 31
From: Bastrop TX
This thread is kind of funny. You guys are a bunch of motor heads. He has a car that is running a top speed of 75 MPH @ 5500 RPMs and everyone is trying to figure out why the motor will not go faster. LOL That is a very stock looking setup put together by some that was less then skilled with fuel injection. Going over 5500 RPMs would be the last thing I would do to that motor.
Since the TV cable is still hooked up I would say if the tranny is not stock its not too far away from it. It the PO had switched to a TH350 that would be gone. Most likey the car has blown 4th gears. Even that would not explain 75 MPH @ 5500 RPMs, He should check the gears but the tranny could be slipping in 3rd also. Which is really moot anyway cause its going to take a rebuild to fix the tranny anyway.
Since the TV cable is still hooked up I would say if the tranny is not stock its not too far away from it. It the PO had switched to a TH350 that would be gone. Most likey the car has blown 4th gears. Even that would not explain 75 MPH @ 5500 RPMs, He should check the gears but the tranny could be slipping in 3rd also. Which is really moot anyway cause its going to take a rebuild to fix the tranny anyway.
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Here is a simple test. Pull your shifter into manual low or first gear. Drive the car with light throttle, when the tack reads 2500 RPMs shift into second and note how fast you are going. Do that for all the gears. It should look somthing like this:
1-2 Shift 18 MPH
2-3 Shift 35 MPH
3-OD Shift 60 MPH
After the car shifts into overdrive let off the throttle and just maintain speed. You may feel one more grab, it is normally hard to feel but you should be able to see it on the tach, maybe a 3-400 RPM drop. That is your torque converter clutch engaging. It will only engage at light throttle and it will disengage under any real load even a hill.
Report back your findings.
1-2 Shift 18 MPH
2-3 Shift 35 MPH
3-OD Shift 60 MPH
After the car shifts into overdrive let off the throttle and just maintain speed. You may feel one more grab, it is normally hard to feel but you should be able to see it on the tach, maybe a 3-400 RPM drop. That is your torque converter clutch engaging. It will only engage at light throttle and it will disengage under any real load even a hill.
Report back your findings.
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Another thing is that the engine might not really be at 5500 rpm, and the speed/rpm issue is unrelated. These 90-92 models are notorious for having tachs that lie, usually reading too high. The one on my 91 read double, and a replacement tach read the same. I researched it at the time and the major cause was thought to be the resistor behind the tach. I have a feeling mine may have been related to the ignition module. I gave up, and just got better at doing math as I drove!
If your engine is really doing 5500 rpm down the highway, I think you'd notice it winding out that far as it's stretching every nut and bolt inside!
If your engine is really doing 5500 rpm down the highway, I think you'd notice it winding out that far as it's stretching every nut and bolt inside!
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In the Staging Lanes
Joined: Apr 2010
Posts: 47
From: springfield Illinois
well i took it out again today made a video and got more pics
wish i could show you the video im new to this forum stuff so sorry about the duplicate Thread i know now how to use this forum i am going to take fuel filter off now be back in a lil bit with results
wish i could show you the video im new to this forum stuff so sorry about the duplicate Thread i know now how to use this forum i am going to take fuel filter off now be back in a lil bit with results
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2nd Gear member
Joined: Aug 2009
Posts: 453
From: Perris Ca
You guys need to read all the pages, he already said the trans was not slipping, said it shifted a lttle hard. He said it gets to 75 and then dies down and then picks back up again like it ran out of fuel and then started to get fuel again.
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In the Staging Lanes
Joined: Apr 2010
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From: springfield Illinois
Thanks CarGuy ...
well i replaced the fuel filter,, Its was some what clogged compared to a new one, so I threw it on and its getting gas flow, I feel a difference now really halls a s s but same problem occurs....
i think the tach is way off!
Should i get aftermarket Tach ?
How do i check what rear end i have (stock or other wise)?
Same with Transmission ?
I made a video, if you know a way i can show you it
and i got a few more pics
sorry about duplicate Messages i was new didnt understand "got it down now"
well i replaced the fuel filter,, Its was some what clogged compared to a new one, so I threw it on and its getting gas flow, I feel a difference now really halls a s s but same problem occurs....
i think the tach is way off!
Should i get aftermarket Tach ?
How do i check what rear end i have (stock or other wise)?
Same with Transmission ?
I made a video, if you know a way i can show you it
and i got a few more pics
sorry about duplicate Messages i was new didnt understand "got it down now"
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75 MPH should be 2100 RPMs. If he is really hitting 5500 RPMs then he is bouncing off the Rev limiter. Which is exactly what he described.
In my opinion a 350 running a 305 fuel injection system not going over 5500 RPMs is the way it should work. That factory system just can not supply enough air/fuel, even if you could get past the Rev limiter, but he should be going a LOT faster when he is running 5500 RPMs. But if the tach is wrong and if the owner can not tell the differents between 5500 RPMs and 2100 RPMs and the owner conciders a stock SBC that can not go over 2500 RPMS a "Monster" below 75 MPH then yes the tranny is fine.
If he thinks a SBC is a Monster below 2500 RPMS I would love to see the look on his face when he gets it fixed and hit the 4000 RPM range.
In my opinion a 350 running a 305 fuel injection system not going over 5500 RPMs is the way it should work. That factory system just can not supply enough air/fuel, even if you could get past the Rev limiter, but he should be going a LOT faster when he is running 5500 RPMs. But if the tach is wrong and if the owner can not tell the differents between 5500 RPMs and 2100 RPMs and the owner conciders a stock SBC that can not go over 2500 RPMS a "Monster" below 75 MPH then yes the tranny is fine.
If he thinks a SBC is a Monster below 2500 RPMS I would love to see the look on his face when he gets it fixed and hit the 4000 RPM range.
