Rpm

[72 OJ]

My newly acquire and refresh 1972 240 does 70 mph at 3.7 rpm's....If I swap to a 5 speed tranny how relax will it get ?

[SteveJ]

Here's the link you want...

Edit: By the way, in case you didn't figure it out from the chart, the drop is dependent upon the transmission.

Edited January 2, 2012 by SteveJ

[72 OJ]

Thanks for the link....but no chart ....lets try this question? If a chance a 77/83 5 speed transmission from a 280Z/ZX ...how low will the rpm's be in 5th gear/over drive. Will it be significant ?

Edited January 2, 2012 by 72 OJ

[jmortensen]

77-79 had one 5 speed. 80 is another, 81-83 is a third. All have different gear ratios. Yes, the difference will be significant. Tire size, diff ratio, and trans ratios all matter.

Here is a better link: http://webspace.webring.com/people/cz/z_design_studio/

[72 OJ]

is my current rpm at 70 mph consider OK

[5thhorsemann]

Thats roughly where my 73 runs, about 5500 RPM at 100 MPH.

[72 OJ]

Thanks........I will leave ORANGINA with its current internals.

[5thhorsemann]

I recently aquired a brand-new-old-stock, still in the nissan shipping crate, 77-79 model year 5 speed for the incredible price of "get it out of my shop". I will install it when the existing clutch or tranny give me trouble, till then I'm fine with the 4 speed.

[Travel'n Man]

I recently aquired a brand-new-old-stock, still in the nissan shipping crate, 77-79 model year 5 speed for the incredible price of "get it out of my shop". I will install it when the existing clutch or tranny give me trouble, till then I'm fine with the 4 speed.

Interested in selling that old crate transmission that you recently acquired? PM me if so.

[5thhorsemann]

Sorry, I want the 5th (overdrive) gear, but rite now since there isn't a NEED to fix or replace anything, I'm just going to leave well enough alone. It's been my experience that these kind of swaps can be like opening a can of worms and I don't need any additional headaches at this point. I am in the process of opening a third business, dealing with the state and local governments in the State of Maryland has me frustrated enough.

[olzed]

72OJ. If you want a relaxed type of drive, fit an R180 diff from an auto 240-260-280 Zed. 3.545 ratio.It will stuff your speedo reading, which is an easy fix. Just change the speedo drive on the side of the gearbox.

My 72 with five speed and auto diff in fourth does 3000 RPM at 60mph . Change to fifth and revs drop to around 2600 at 60 mph.

I seldom use fifth.

Edited January 2, 2012 by olzed

[72 OJ]

2600 rpm's at 60 mph ...wow, I will keep your RX(auto r180/3.545 ratio) for future mods. What tranny completes this formula?