[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
RE: 4000 turbo conversion advice
> and I, have 3
> > 4kq's an '84,'85 and my '87 the '84 only makes about 19-20
> mph per 1000 rpm
> > while the '85 & '87 each make 22 mph per 1000 rpm in 5th
> gear. Since we have
> > confirmed the final drive is the same (4:11)and that the
> tires are all the
> > same (blizzaks) then the transmission ratios must be different.
> That's what the consensus is. BUt if the brochure is wrong about
> one of the ratio's, which one. How do you know the 84'
> ratios are right?
Most likely the ratios were correct at the time of publication, However the
'85 with a January '85 build date has the older "UR" code rear diff and the
newer "US" code transmission. I accept, somewhat blindly, that the
published codes are correct for the '84 or at least close. Some simple work
with the calculator shows an expected 19+ mph/1000 rpm with the .83 gears
and a tire that rolls 918 times in a mile.
When I was under the erroneous illusion that later 4kq's had 3.89 gears,
working backwards indicated a 0.78 fifth gear, as Phil noted the Urq has.
(28:36 gears) Working backward with the 4.11 gears and the (verified) 22
mph/1000 rpm, the expected fifth gear ratio is around .73 about what the '91
> THey did change the trannies. Says so in the bently, newer ones
> hold a different amount of fluid too. Question is, what
> changed inside
> them with the gears.
Hopefully, someone with a fiche will post a nice gear teeth table for the
4kq as Phil has done with thye Urq.