Topic: Not sure about my tach
in Forum: C3 Engines
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Just put a Richmond 4+1 in my 73. 5th gear is 1:1, and I have 3:08 gears in the rear, stock size tires. Just curious if anyone can tell me at 70 mph what my tach should be reading? In 5th gear @ 70, I'm taching 3000 rpm, which seems a little high to me. Don't know if the tach is a little off. I thought I'd be taching about 2400-2600 rpm's.
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Duncanville, TX - USA
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
If 5th gear is 1:1, that's direct drive, which is the same thing as if you had a stock 4 speed, or a 3 speed auto.
My '74, with 3:36 gears, tachs around 3200 @ 70mph.
What did yours tach out at before the trans swap?
Then again...IF the new trans has a 1:1 high gear, it's still the same as what you had before, with the four speed...it should tach the same.
My '74, with 3:36 gears, tachs around 3200 @ 70mph.
What did yours tach out at before the trans swap?
Then again...IF the new trans has a 1:1 high gear, it's still the same as what you had before, with the four speed...it should tach the same.
Joel Adams
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Lifetime MemberManteca, CA - USA
Joined: 11/20/2005
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Vette(s): 1978,two tone,Metalic Rootbeer & gold
1975 L48 4 speed
Well Chris, I'm running in your desired range with my super T-10 at 1:1 in 4th but with 2:73 gears in back.
Jimmy B.
Just can't wait to get on the road again. 
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in Forum: C3 Engines
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