OM602 target cruising rpms

[PickleRick]

Hey guys. I'm finally done with my TDI Toyota 4 runner resto mod and now starting on the little ladys om602 discovery 2 build.

I'm tossing between using the land Rover 3 speed with locking overdrive but a 6l80e would net better gearing options.

4.03, 2.36, 1.53, 1.15, . 85 and . 67

Currently has 33 inch tires and the stock 3.54 gearing. Likely ok for stock trans but in order to use the 6l80e we should go min. 4.88. I think the 0 to 60 times and daily drive manners for city traffic would be nice.

This would bring her to @3000 rpms at 90, a speed we hit frequently on our highways to hang with traffic.


I have never driven a 602. Planned mods are an upgraded injection pumps and a TD04 turbo with fmic. Also a good egt gauge as the turbo will be a trial and error situation unless someone can make suggestions. Shooting for 150 to 175 hp and 250 to 300 ft lbs of torque.

I want to keep her in comfortable cruising rpms as to not lug the motor. Please let me know if the gearing needs to allow more rpm for given speeds..


Attached is a gear calculator I hope someone can check out and make suggestions if rpms need to be higher or lower.


The following chart lists the road speed you will be going while the engine is at a given RPM. Road speed is calculated based on the transfer case and underdrive being in high range.

Road speed at given RPM in miles per hour
Gear in first column.

2000rpm 2500rpm 3000rpm
1 10 12 15
2 17 21 25
3 26 33 39
4 35 44 52
5 47 59 71
6 60 75 90
7 - - -
8 - - -


Thanks ahead of time guys.