smoky beast

I am going to rebuild/replace the NV4500 transmission and upgrade to a Dana 80 rear end in my '97 2wd single cab 2500. Which tranny NV4500 or NV5600 and which rear end gear ratio 3:55 or 4:10 would have the best 1/4 mile ET?Also I know an automatic would be faster but which of the manuals would be quicker for 1/4 mile drag racing?

many thanks again
Smoky Beast

mcoleman

The NV4500 would probably work better for racing.

JTaylor

For drag racing the NV4500 would be a better choice. The NV5600's gear ratios are much closer together, which is primarily better suited for towing. And personally I would go with 3.54's, 4.10's are going to hurt your trap speed.

Box5

3.55's for sure hands down. They'll let you pull longer in each gear. And the Nv4500 i'd think would be better because of the shifts.

Tiger Rag

Yep, agreed. NV4500 and 3.55's if you're not going to do an auto. The 4500 will also be lighter in addition to the spread out gear ratio's. Make sure you do your input shaft upgrade and the nut backing off 5th gear (I don't have one so I don't remember exactly what the 5th gear isssue is).

displacedtexan

I agree on the 4500/3.55, but IIRC you should already have a Dana 80, I'm pretty sure all the manuals have them.