Any experience with the 502HT

[77crewcab]

considering this for my crewcab along with a 4L80E and GV overdrive and Edlebrock pro-flow mpfi, and Thorleys. Looking to find out estimates on gas mileage with mild driving style for city and highway empty and under load (about 8-9000) Any input or experience with this would be very helpful.
Thanks
Monty

 

[dyeager535]

I doubt you'll find many with experience with all of those components.

If I were to speculate, unloaded, freeway, I'd say 10-12 at best.

A 502 is a big engine, no matter how slow you turn it, or how much load it's under, it's going to drink a lot of gas.

My dad has a carbed 454/465/205/GV/4.10 setup, and 11 is about the best he gets on the highway. City is about 9.

Loaded or unloaded doesn't matter, even a 10,000lb trailer doesn't make a difference. Truck weighs in around 6000lbs empty as I recall.

 

[Z3PR]

We put one in a 78 C30 crew cab duelie with a 4bbl carb, stock exhaust manifolds, TH400, and what ever gears were in the rear. MPG's were roughly 10mpg.

 

[atho]

why would you want to double up on overdrives? go with either the 4l80e or the GV, not both.

 

[dyeager535]

I can see double overdrives working, especially with an engine that large and with 3.73's or numerically higher.

Not positive on the 4L80E's OD ratio, but IMO the GV's is pretty worthless (.75 IIRC) so doubling them up might net a fairly good final ratio.

It would however, be expensive for the gains you'd net. For the cost (seriously) you could buy a cheap commuter car or something. Obviously if you used the truck for a lot of trips where you were empty in one direction it might be worthwhile, otherwise suck up the mileage loss and buy another vehicle for when you need economy.

Neither the GV or the 4L80E are anywhere near the "cheap" price range.

 

[77crewcab]

Thanks guys thats about what I figured on the mileage didn't expect anyone to have the same setup I looking at but mainly opions of the engine and how it tows. I'm looking at the GV unit cause from my understanding you can still tow with the GV engaged and so still have the OD even when the 4L80E is in Drive. I know it is a heavy beast of a truck but fits my needs just right. Surprisingly I'm getting 9 city now with a Very tired 454, a screwed up Holley 4bbl and open exhaust (the donut gaskets are gone, can you say no TQ) I think I could live with the 502 very well. At least until I can have the vehicle down time to do a body off build (and extesion) and Cummins conversion. (Think Top Kick with a sleeper but in a smaller version)

 

[77crewcab]

Any body else have some experience with the 502HT or know of someplace online to get some feedback on it? I can't find much info or anything on personal experiences. I did find one guy's report on the Sallee chevy sight with about the same setup I am looking at in a burb. Just looking for some more input.