high rpms at highway speeds
#1
high rpms at highway speeds
My 89 Camaro runs at high rpms at highway speeds. I'm sure the car is in overdrive. I checked the tach, thats accurate, changed filter and put in new tranny fluid, Can you guys suggest anything else ?
#4
Re: high rpms at highway speeds
This all happened when my radiator blew and the engine got hot. The repairs were done but afterwards I noticed that at 60 mph I am at 3300 rpm.
#5
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: high rpms at highway speeds
How do you know the tach is accurate?
You can check the accuracy of the speedo with a GPS speed app with your phone.
I had a 91 454SS pickup truck. OD transmission, 4.10 gears and 28" tall tires and it was close to 3000 rpm at 60 mph.
You can check the accuracy of the speedo with a GPS speed app with your phone.
I had a 91 454SS pickup truck. OD transmission, 4.10 gears and 28" tall tires and it was close to 3000 rpm at 60 mph.
#6
Re: high rpms at highway speeds
checked the tach with a aftermarket tach, both read the same exact rpms at highway and regular driving speeds. The car always ran 2000 rpm at 60 before the radiator blew
#7
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Car: 1987 Z28 Camaro
Engine: 305 LG4 4bbl
Transmission: TH700R4
Re: high rpms at highway speeds
torque convertor locking up? sounds like its not locking at high speeds. even so that still seems pretty damn high
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#9
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Car: 1987 Z28 Camaro
Engine: 305 LG4 4bbl
Transmission: TH700R4
Re: high rpms at highway speeds
if you get under there, apply 12v to one of the lines on the tcc solenoid and see if it clicks.
#11
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Car: '86 Camaro, '94 Camaro, 3 others
Engine: LG4 ->L29, L32->LR4, L36, LG4, L31
Transmission: 700R-4, T5WC, 4L80E, SM465, 4L60E
Axle/Gears: 3.42, 3.23, WTB/WTT 2.93
Re: high rpms at highway speeds
#12
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Car: '86 Camaro, '94 Camaro, 3 others
Engine: LG4 ->L29, L32->LR4, L36, LG4, L31
Transmission: 700R-4, T5WC, 4L80E, SM465, 4L60E
Axle/Gears: 3.42, 3.23, WTB/WTT 2.93
Re: high rpms at highway speeds
No way this thing is shifting to OD, no matter where the shifter is placed.
2000 at 60 should be a 3.42 if 700R-4, so that should be 3100 at 60 in third with the converter unlocked in third. 2000/0.696=2900+200 slip.
If this is a T5 with the 0.63:1 fifth, then the math works with a 3.73 or 3.91 axle, depending on tire size.
#13
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Car: 1987 Z28 Camaro
Engine: 305 LG4 4bbl
Transmission: TH700R4
Re: high rpms at highway speeds
yeah thats why i said it still seems pretty damn high.
i think with my 305 with the 700r4 at 60mph (somewhere near ~100km/h here in aus) its in the mid 2000's in 4th without lockup
i think with my 305 with the 700r4 at 60mph (somewhere near ~100km/h here in aus) its in the mid 2000's in 4th without lockup
#14
Re: high rpms at highway speeds
Just took my 89 Camaro out for a drive, at a steady speed while in od I tapped the brakes and the rpms went up 200 to 300 rpms, that tells me my torque converter is working so I can rule that out