[Supras] RPM vs. Speed

[Dave Koos]

Bill,

I previously owned an '89 n/a 5spd and had this same complaint!!  Knowing what I know now, there's an easy way to change things up!

The non-turbo Supra 5spds came with 4.30 gears.  The "sport package" may have included a 4.10 LSD, IIRC.  The non-turbo autos were geared with a 4.10 diff and run lower rpms because of how the transmission itself is geared.

The early '87-88 turbos 5spds came with 3.90 diffs and the '89+ turbos all got 3.73 LSD diffs, regardless of auto or 5spd.

My '86 MK2 5spd has the 4.30 diff and pulls ~3300 rpms at 70mph on the highway.  Still gets decent gas mileage too, but I only live 3 miles from work now.

I'd suggest finding a good 3.90 LSD out of an '88T and put that in.  Maybe have it rebuilt first if it's got high miles on it.  Will help with rpms and fuel mileage for sure.

HTH,

Dave  92T & 86 P-type
Mesa, AZ
http://www.azsupras.com/suprattop.htm
http://www.azsupras.com


----- Original Message ----- 
From: Dennis Z 
To: Bill Wright ; supras at supras.com 
Sent: Sunday, February 24, 2008 8:54 AM
Subject: [Supras] RPM vs. Speed


Bill... the way i see it,  you have a automatic gear in it [4.30] and 
you should have 370 or 390...
at 60   2300rpm  70   2650rpm    80  3000rpm this is with a 3.70gears
Now i have a shorter tire than stock so the rpms maybe a little 
different also a little less in compression.
good luck Dennis


----- Original Message ----- 
From: Bill Wright 
To: supras at supras.com 
Sent: Sunday, February 24, 2008 7:13 AM
Subject: [Supras] RPM vs. Speed


All this talk of speed brings to mind another question....Since we only have one of these cars ( so far....) we have nothing to compare it to, in similar vehicles. My son had the use of an Eclipse for awhile.  When he got back into the Supra, he was concerned that the rpm at highway speed was higher than the Eclipse. In fact, at 65 mph, it's higher than a 4Runner, a Ranger, most other passenger cars I have been in and is about the same as my old '87 Ford F150 pick-up, which could pull stumps. It's around three grand at 65 mph. It's  an N/A, 1990 with a five-speed. Is this about the same as everyone else? I can't imagine that there is a mechanical problem, as the clutch seems fine. Anything else would just fail completely. Another question is fuel mileage: It always seemed low, before. That would be expected, with the condition the engine was in. We have not checked since the rebuild; but what does everyone else get...assuming we're not going between 85 and 140.....

Bill
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