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I know this has been done a million times, but how much difference will 3.08 ratio affect my speedo? is it worth all the work (and stinking out the house with the smell of diff oil) to get my standard 253/trimatic 14inch wheels taking off a little better? car hardly goes out, only to shows and swap meets etc so I dont care about extra fuel costs. I just want a little bit of pull off the line. Cheers, Scott
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Kind of funny u say there isnt enough oomf from that combo (i have 253/tri/278). My 2.78 is gr8 off the line, and I am not even trying (no it wont smoke or spin wheels but it is quick). The 3.08 diff will take your revs at 100kmh to 2500 rpm, the 2.78 aro
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Its got a bit off the mark, but missus wont let me get out of control with this car, so its just a clean cruiser. No chev no 9inch, not even aloud a gts steering wheel. So its white walls, sun visor, air chief. She cant see the diff gears, so Im thinking
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ive got a a 2.78 diff in my hq, its good for cruisin down the highway and takin it easy around town, thats what i like doing in it so it suits me fine
however its a bit slugish off the line but once the revs get up it realy takes off
if you want that li
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Go for the gear change 3.08 will be fine just add the trimatic coloured adapter (rares used to carry em). A 253 with twin 2" sounds nice too. Works for me. Ditto the air chief and sun visor. Got rid of 6.00 skinnies tho. Put on some GTS rims.
Cheers Jo
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I do have a set of HPC coated pipes with a 2 1/4 single pipe and a holley 350,so it sill goes and sounds ok. Had a 2" twin set up on it but it sounded a little like a wet fart to me. Im thinking the gear I need is pink.
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Back to Scotts original question, seems to me that if all other things stay the same, changing from a 2.78 diff to a 3.08 diff will reduce revs by approx 11% for same speed and increase speed by approx 11% for same revs.
David
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Correction:
If all other things stay the same, changing from a 2.78 diff to a 3.08 diff will increase revs by approx 11% for same speed and decrease speed by approx 11% for same revs.
David
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hey guys.. slightly off the OPs question.. sorry in advance, but i have 3.55s behind a 4 speed manual and 202..
what kind of revs am i looking at for 100km/h?
cheers
Cheers, James |
Cheers, James |
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pont69. its about 32.5 km/h to a 1000rpm. for a 3.55 ratio. std 14 inch tyre.
3.36 ratio = 34.2 km/h at 1000rpm.
3.08 ratio = 37.4 km/h
2.78 ratio = 41.4 km/h
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hey rosenberg,
wonder what 308t400 3.35au diff, and 15inch 175tyres will end up at 100klm ??
be interesting?
cheers
bcb
said the weathercock to the wind,> "how tedious and monotonous you are, can you not blow in any other direction, but in my |
more than basketcase than a bear!
DOH!!! |
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With some transmission slip about 3000 RPM, +/- 50rpm depend on tyre pressure and tread wear.
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