[Super73]

A buddy borrowed my chassis that previously had my N20 motor in it.

His old combo was a forfed 6.0 with ported heads and smallish cam with a 76mm turbo. He has a somewhat small converter (3,600 I believe). With a 2 step and a 4L80e he went 1.7x 60's at 12lbs.

In my truck he switched to twins but continued with my 4.22 gear, 32" tall tire and 6,200 rpm converter with my power glide. He went 1.33 60'

Moral of the story.. CONVERTER CONVERTER CONVERTER...

If you can't get to your peak torque instantly, you will never move out as fast as you can.

I am assuming you have a 60e or 80e? If that's the case, don't be affraid of "big" converters as you can lock them for street use.



Advantages are:

Being able to build more RPM while being on the brakes, less likely to push through them.

Quick jump in RPM when you stab it will spool the turbo faster (high exhaust speed)

TQ multiplication will be greater. If the converter has a 2.4 STR, it will effectively multiply TQ at stall rpm by that amount. So if NA you motor makes peak tq at 5,000 rpm due to your cam profile, having a 5,000rpm converter would more like 1,200hp on the hit.


Tune gearing to be +/-200 rpm past peak hours rpm through the traps. Then Convert accordingly.