different stock gearing?????

[lucky03602]

okay i own my 2nd 240. (first one had alot of body rot and i didnt wanna deal with it)my first one had the rpm 5k shutoff at 115. this one dont. first couple of times driving it it seemed shorter gearing but i coulndt quite figure out if it was me or the car. it has NO 5k shutoff and for the hell of it on the interstate i decided to figure out if it redlined at 115 or what, but before i did i found out i was doing 70-75 mph at around 4-4250 rpm which is way different from my other 240. i didnt even find out what the top speed was.

both of the 240sx are 1990 completly identical. tha only difference is my gold one (one with the 5k shutoff) was made in the northeast (where i live) and my new red one was made down south and came up from georgia.

can anyone help me figure out this dilemma?

[lucky03602]

oh yeah....both are manual and i dont know if a manual swap was performed in either.

[corn322]

... but before i did i found out i was doing 70-75 mph at around 4-4250 rpm ...

what gear where you in? 5th?

[lucky03602]

sorry yes 5th gear on the interstate in my new 240 at 70-75 mph im at 4-4250 rpmsin my old 240 (again identical cars) at 70-75 in 5th gear id be at like 3500 rpms if i remember right.it feels just like either the final drive is shorter and/or 5th gear is alot shorter ratio.

[Luke]

There is a replacement final drive gear which switches it from something like 4.08 to 4.25 (don't know if that's correct). Does this 240 accelerate faster than the other? Top it out and let us know how far you got it

[lucky03602]

i will say it seems i have to shift it alot more often yes, as far as topping it out today on the interstate i did around 100-105mph at 6k, at about 80-85 im at 5k, and at 70-75 im at about 4k, all in 5th gear.i would assume that it will do 115 at 6500rpm or maybe 7k but yes it will do it

whats more about this optional final drive gear you speak of?

[corn322]

I heard nismo makes a 4.60 rear end. maybe you have it.

[lucky03602]

any idea as to where i can find out what i got/is goin on with my car??

[WeldingHank]

if you had a 4.60 you would be doing 105 at 5000RPM's. so, you have something lower than that. you can mark the driveshaft and turn it by hand and count how many times you turn to shaft to make the tires turn once.

[lucky03602]

at 5k im actually doing 90 mph (checked it lastnight)

[corn322]

what size wheels and tires do you have?

[lucky03602]

i have the stock steel rims with the optional 205-60-15

figured something out about the whole thing though, this whole time it has been the tachometer.

yesterday on the way to work (i drive mainly on interstate 91) my friend and coworker pulled up behind me in his fathers chevy lumina z34 and of course im not going to let him get me so i got on it and next thing i know i hit 5k in 5th gear and i was doing 115 and my car shut off

so that means that my car has the stock rear end (4.08 if im right) and that my tach or tach signal or something is wrong.

thanks for all the help though!!!

[WeldingHank]

that was going to be my next guess. that either your tach and/or speedo was off.

[flohtingPoint]

Try courtesy parts, they sell R&P kits. If you get the 4.6 to work, let Greg and I know, as we are both curious about how it will fit.

If, by chance, you dont go 4.6, they sell a 4.36, which is in the rear end of JDM S series vehicles.

PS: You think your 4.0 is bad? Try a 3.91, which is what all of us in Europe have stock.

[erollinc]

i was thinking about going 4.40 how bad would it be on the highway? it would be fun as hell around town