L31MaxExpress
I'm Awesome
I bought LD K2500 ECSB with the NV3500 with 9800 mi on it in 1992. The NV3500 was a absolute POS, replaced once under warranty, again at 150k, and when I sold it at 285k the trans was in the process of fragging 5th gear....again. I really liked that truck—the rest of it was almost flawless and gorgeous.
With apologies to the Mopar 318 and FOMOCO 1st gen 302, the 5.7 TBI motors may be the longest lived cast iron gas V8 ever devised by humankind. It’s no secret, it’s a low RPM motor. The TBI’s outlast the 5.7 Votecs, and the 5.7 Vortecs outlast the 3rd gen 4.8/5.3/6.0’s which operate at even higher RPM’s.
Stoplight to stoplight my 5.3 beats my 5.7’s, but running up the mountain passes the 5.7’s have a wider power band, don’t hunt and peck through the trans as much, and pull the hill at lower RPM’s.
Also, that 91 TBI got better fuel mileage than the 5.7’s and as good as my 5.3.
Problem is, the TBI’s don’t have the power needed to negotiate Mtn highways at altitude here in Colorado.
When the Express van was stock never had a stock 5.3 get around me until I was running about 70+! My old TBI G20 with headers and an edelbrock intake manifold would hold a 5.3 off up to about 60 too. Acceleration from a stop with all the 5.7s torque was never a problem, they just get asthma on the top end in factory form.