help with drivetrain please.

[donnie89240sx]

ok i couldnt find anything to help me out. this is what i have a 1989 nissan 240sx coupe with the ka24e and a 5 speed transmission. the internals came out of an 85 300zx for the transmission but i had to change the reverse gear and the input shaft for it to work peoperly . i can do 2200 rpms and i should be close to highway speed but im only doing 46 mph in 5 gear using around 2200 rpms. at 60 mph im turning 3000 to 3500. what can i do to correct this?i know theres something but i cant think of anything except bigger tires,lol but that will definately kill the speedometer because it will be reading the wrong speed.and i know my speed isnt off because when i am on the road i can do the speed limit and i am keeping up with everyone else. if anyone got any ideas on what i can do i would seriously apreciate it.

[donnie89240sx]

i have some pictures i took with my cell phone. how do i insert them in here?

[Fla240sx]

3000-3500 is a pretty damn big gap

if its like 3000 thats almost normal

3500 seems extreme

although I didn't know the z31 N/A and 240sx had different gear ratios in the transmission.....................

[donnie89240sx]

that sounds possible i was thinking about that earlier today. that would definately explain the shorter gears also. well thanks for your help i will just have to get another 240 transmission or what other car would have a transmission with close to the same ratios would u know? well thanks for your help. have a good one.

[johngriff]

That trans has a very short gear ratio, because the final drive of the differential was quite long.

The easiest fix is to get a J30 Differential plus axles and bolt it up to your 240.

Then you will have:An LSDBetter AxlesA longer final, making your trans setup more manageable.

Its all bolt in except you will need an "ABS" style rear driveshaft from a 91-94 240sx, but you should be able to source that from the junkyard as well.

[donnie89240sx]

well i can get j30 hubs,calipers,rotors,axles,rearend,and the driveshaft in my car is out of a 92 240sx. but i can get all of that under 200 dollars. i was going to get that lsd anyways,lol.i can get the rearend alone for like 75 dollars. im just going to spend the money and find me another transmission from a 240sx imma call one junkyard and see if they got any to fit the 89throuh98 since i was told they would all work. i appreciate all the info.

[donnie89240sx]

ok i have a big question. i put a 240sx transmission back into my car what should be the rpms for doing 70 mph? so i know if its right or not i can do 44 mph now and turn 2 grand does that sound about right? and thats in 5th gear. and someone got to that j30 diff before i could.