i trying to get a higher top speed out of my 89 turbo and someone told me to take the rear from a 87-88 turbo because the have a longer gear ratio for a higher top speed...now what i wanna know is is this true and if it is will this bolt directly to my car or will i have to do some work on this or can i use a rear from a mk4 turbo and will that bolt directly to my 89 turbo

How fast are you trying to go?

My drinking team has a racing problem!!

well they said the top speed with the rear that i have is around 150 vi wanna keep up with my friends rx-7 at around 180-185 tired of the lil rotory p.o.s. wupping me all the time

The number for the 87-88 is higher which means the gear is shorter or lower, and will reduce speed. Torque and speed are a trade off in a gear box.

Anyway, The 87-88 has a 3.91 and the 89+ is a 3.73. Regardless you have a speed limiter set to 156. Electronics can defeat that though.
Good luck finding a taller gear in the aftermarket. Your ring gear is 8.07 " diameter I think.

In Tressel we trust.

Once again the truth be told by my homie Nick thanx bro once again u help me out (the other kid i talk to told me the oppsite witch i thought didn't make any sense......but thanx once gain

oh yea... what would i use to bypass the speed limiter

[This message was edited by supraturbo01 on February 05, 2003 at 06:39 PM.]

Well, if the gearing is really tall, you will slow down also. The taller the gearing, the more difficult it is to accelerate. Take an old 5.0. It has a 2.73 and .68 O/D. If you could redline that car, it would be going around 200 mph. Obviously, the engine needs around 700 hp and aerodynamics to do it. But if the gearing was shorter, you could more easily get redline, and possibly better top speed. This isnt confusing you is it. With a 3.73 a 5.0 will go about 155. Thats 10 mph faster than stock with shorter gearing. Total speed achievable is lower, but not usable speed.

In Tressel we trust.

Keep in mind the more you drop your gear ratio the longer it will take to get up to speed without any more power output from the engine.

so what would be the best way to up the top speed a lil bit

How fast do you think you need to go. If you get caught in the US doing 180, You will never own a car again. Maybe Richmond makes a tall ring and pinion ratio. I know they make them for the Toyota trucks.

In Tressel we trust.

the real reason i want it is just for bragging right

then just lie about it.. racing a mate at 180 mph is crazy anyway. I wouldnt like to take a mk3 to 180.. theyre just not built for it.

If you want to go 180, either do it properly or buy another car.

adi
1992 original JDM JZA70 2.5tt 'Limited' - Decat, hybrid turbos.




http://www.jzasupra.com

true or i can just deal with the 156mph