L31MaxExpress
I'm Awesome
Absolutely. Tahoe has 32" tires and 3.42s with the 4L80E. It runs like 1,800 rpm going down the highway and even pulling 6,000+ lbs of flat deck car hauler trailer + car on it, will hold overdrive almost the whole trip.One of the lessons I learned from playing with 500cid Cadillac motors is that more gear is a crutch for motors with no torque.
One of the 500 I had my hands on had a switch pitch built FWD TH425 from the days the GMC had a 403 Olds in it. Moved a 26' long, 12,000 lbs motorhome easily at 10 mpg with port fuel injection. Used a modified stock Caddy 500 PFI intake, with a GM454 TBI sans injectors and a custom tuned 7730 TPI ECM. Switch pitch in a motorhome is awesome, when it is in high stall mode from a stop the 500 would burn the front tires off it. The 403 got like 6-8 mpg previously with a Q-Jet because it was either in 2nd gear or into the secondaries in 3rd to run 65 mph. The 2nd 500 was in a late 70s K5 on 37s. Stock 3.42 gears. That 500 could get 17 mpg pulling around that K5 with a Q-Jet and no overdrive. My other Cadillac experience was a 425 into an 82 G30 cut-away van motorhome to replace a tired low compression 160 hp 350. Q-Jet carbed 425 hauled its 10,000 lbs around effortlessly.
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