would I get a better MPG with a 4.3

[iluvmy72]

I have a 4.3 throttle body engine and 700r4 tranny form a 88 astro van. The van is in sad shape but the engine and tranny have been rebuilt. Would this be better for economy if used as a daily driver? The truck currently has a standard 350 engine in it with a 4 barrel carter carb.

[CHEVIBUBBA]

if your simply running empty to work & back etc. then, yes.
primarily due to e.f.i. & o.d.
the throttle body injection isn't that much better than a carb that is correctly tuned but, it is better.
i would expect about 5% better due to e.f.i., 7-10% better for v6 vs. v8 & 10-15% due to going overdrive.
if you start pulling or hauling your gonna miss the v8!& your mileage will likely be worse.

[Longhorn Man]

My observations with a 92 W code 4.3 (that's the Vortec injection) was pretty poor MPG even when the engine was still fairly tight. Had it in a 92 S-10 blazer with the 4l60 (e?) tranny, and I think the best I ever saw out od it was 21 MPG...in a small light weight body. It was OK performance wise, but like he said, put a trailer on it, and it is a total dog....heck, put 4 full sized men with duffle bags in it and it is a dog.

[longhorn71]

i think the milage would be worse even empty.the older trucks are way heavier than the newer ones.So the engine would be workin harder to pull just the truck around.IMO i would swap the rear gears and or put an overdrive trans in it

[LUV2XCLR8]

PERSONALLY, IN A DD BEATER TRUCK, I THINK A 4.3 IN A 67-72 WOULD BE