79 f-3504x4 460 nv4500 trans 4:10 gears 33-12.50-16.5 tires anybody getting anything above 9.1 mpg? changed holley 600cfm carb to holley 750 cfm carb. 8.6 mpg -600cfm to 9.1 mpg-750cfm with#72 jets stock cam performer 460 manifold dual exhaust. truck regularly pulls 16ft. horse trailer with horses. any tips besides 12 valve cummins engine swap?

 

maybe try a skinnier tire? electric fan?

side note, did you swap in that NV4500 yourself?

 

A 460 is what it is. It's not really known for gas mileage. If you're going to pull alot, I would just buy a diesel truck if you want any better gas mileage. just my opinion.

 

460s are just thirsty. I dont think you can do anything to get much better then 10 mpg

 

I saw no mention of headers, any head work, aluminum items for weigh savings, electric fan, different pullies, a different cam, etc.

 

psquare, you nailed that one. X2 on that!

 

A machinist friend and I did the swap with a nv4500 swap manual. The tranny is out of an early 90's GM 1 ton with 6:34 granny gear.We made an adapter plate from a piece of 1" plate since there are no adapter plate for the early tranny. We used a GM 4wd mainshaft and installed a GM input gear in the NP 205 so no adapters on the mainshaft. We cut the input shaft on the NP 435 and the NV4500, cut an index pin on one shaft and bored a hole in the otherand made sure the overall length was correct. We used a welding procedure where we preheated the input shaft and welded the shaft with 100,000 psi tensil strength wire. No problems with the input shaft after 5 years of use. We used the original Ford cluch plate. We used a GM tranny mount and had to do some alterations to the crossmember. We lengthened the front driveshaft and shortened the rear. We had to relocate the transfer case lever and cut a hole in the tranny cover. I didn't notice any increase in mileage but it made the truck go faster. Total cost including the tranny approximately $1300.

 

I wish I got 9 MPG. I get 7 with my 351M

 

Change it to a 445ci

 

Hmmmm your best bet for better mileage with a 460 is to pull the truck with a horse

 

9 with a 460 is not bad at all.

 

Just curious. Do you have E10 fuel there? When we went to that locally, I noticed a 10-15% drop in fuel economy, in all my cars....

 

Now thats damn funny!!😎What kind of horas should i get?A pinto?😉

 

Better mileage from a 460? Sell the truck and buy one with a 300 in it. 9mpg isn't all that bad. Hell even the 80's and 90's trucks with the 460 got the same mileage!

 

I had an 84 with a with a 300 in it. It only got 12mpg. That's the reason I went after a 75 or earlier 460. Figured if I was used to getting bad mpg, I might as well go after the big engine. Best mpg I had from a truck was my 83 F150 w/351W and 3spdOD. That one got me 15mpg highway. With my 460, I get 11mpg. I have dual exhaust, Holley 4 barrel and no AC. I like it.