do you think 4-11's are too low?

[Jaykuo]

do you think 4-11's would be a bad choice for a stock 1972 240z?

my lil toyota pickup has em...and i like the tourqe....but my truck is also a 4banger....

would the new gears be too low for the bigger 6?....what gear ratio would even it out so its just about the same?

[2ManyZs]

A 4.11:1 rear in a stock 240 would be a perfect choice if you put in a 5 speed out of a ZX or even a 280 Z. You will get a big increase in the acceleration in the lower gears and with the overdrive you will even end up with a higher overall gear ratio than stock. In other words you will turn less rpm's at highway speeds in 5th gear with the 4.11 than you would with the 4 speed and the 3.36 stock ratio, but gain a lot in the lower gears(especially 1-3) to win those stop light "races".

See the post in the tech articles for the ratios for the transmissions combined with the 4.11. With the ZX 5 speed you could even go lower than a 4.11 to a 4.37 without turning more rpm's at highway speeds.

[Jaykuo]

4-11's...would be too low for the 4-speed then?...or ok?....cause i really dont want to have to switch transmissions.....i just wanna keep the 4 speed...

[2ManyZs]

A 4.11 would be way to low for a 4 speed, you would be turning 3k+ rpms at highway speeds. That would get annoying really quick, and kill your gas mileage too. You might want to think about a 3.54 out of an automatic Z. It will increase your rpm's a little, give you a little better acceleration and will be a simple bolt in if you don't want to change to the 5 speed.

[Jaykuo]

could i just buy the gears?......i wouldnt have to get them from an automatic would i?

[2ManyZs]

Well, you could check it out, you may be able to buy the ring and pinion for a 3.54 but right now I'm not sure. There used to be a big selection of ring and pinions (new) that you could purchase, but the supply seems to be drying up.

Try www.nismoparts.com first then widen your search to include all the aftermarket parts suppliers. Then buy according to who is the cheapest.

[Jaykuo]

they got the gears but they want a hella lot of money for em......

i think ill stay stock for a bit...

[2ManyZs]

I never said the gears were cheap did I? I know, I bought a set for an R-200 years ago and they were expensive even in 1990.

That's why I suggested trying to find a complete diff out of an automatic. You may be able to find one from a 77-78 auto since I believe they may have had an R-180 in them, not sure if they used R-200's and R-180's in the later years of the 280 but I know for sure they had R-180's in some, if not all.

[Dave Sommers]

I am running a 411 right now with a zx 5 spd and it works out just fine. Sorta like bolting on 20HP the easy way... With a 4 spd it may be a bit buzzy, but the slightly higher ratio of the final drive in the 5spd takes the edge off. If I was going to drive to LA from here in the east I would be tempted to go back to a 354 to get the highway rpms down. But for local travel, it works just fine.

[Royce]

Jaykuo,

Changing the gears would be way more complicated then finding a 3.5 R180. For one you would have to pay "new parts" prices, as you found out they are not cheap. Then you would have to take the diff out and change the gears, which in my opinion is way more complicated then finding a used diff and swapping. Setting up a diff with new gears is a very complicated job that requires experience and specialized equipement (cha ching).

I agree that using a 4.11 diff woud be geared way to low for a street driven 4-speed Z. For example, using 195x70 14 tires you would be at aprox. 3700RPM at 65MPH in 4th. With a 280Z 5-speed that would put you at 3200RPM which is similar to what 4th is probably with your current diff. The tire size will play a big role in all this too. Check out http://www.geocities.com/z_design_studio/ to try different trans, diff, tire options and see the resulting engine RPM/MPH relationships.

Have fun!

[Alfadog]

Nice site!

Hey also guess what, if you stick some 50" wheels on a Z, in 5th gear it'll go 414mph!!!

hehehe

[dhayes5]

Dave,

Is your 4.11 an R200 or R180? What vehicle is it out of?

Why did you go with this vs. a 3.90 -- is there that much difference in acceleration?

I have an '83 five speed that I am rebuilding to go into my '72 and am in a quandry as to what to use for a rear end. Ther R200 requires a new tranny mount (unfortunately I just replaced my stock R180 mount last year) and a different mustache bar). Finding an R180 with 3.90 or 4.11 gears is tough also plus you have to do some ugly work to convert the CV joints to work with the '72 half shafts.

What is a good price to pay for a good used rear end? Arizona Z car wants $175 for a 3.90 R200 plus shipping to NC. Adding in the mustache bar and tranny mount, this starts getting expensive. Though the expense may save some installation headaches.

Any thoughts?