55 top speed

[roundhouse]

Thanks guys for all the posts, when I said “55 top speed” I ment 55 was a comfortable cruzing speed. I have 265-75-16’s on my truck as in the avatar pic,I drove the truck with the stock wheels 235-85-16’s for a few months and it was running high RPM’S at 55 also. I don’t have a tach so I’m not sure on RPM’s.Could my Quadrajet carb be holding me back? I don’t see how I could go to a taller tire short of changing wheels,,,the 85 series I had on it never helped.

Taller tires is for sure the easiest and cheapest way to lower the highway RPM

Gonna lose some acceleration
But the only way to keep the fast acceleration and improve the tip speed is swap the trans to one with overdrive




The wheel size is not an issue
I have 15” rims and 35” tires

With 3.73 gears and an overdrive 5th gear that hardly ever gets used

We had 33’s on it with no lift and had no problems


On my bronco I have 4.11 gears and have run either 33’s or 35’s

You can run 33’s with no lift

 

[Craig 85]

My last truck was a '79 K15 (350/350/203) with a 3/4 axle swap (4.10 gears). I had 33x12.50x16.5 tires that were about 32.8" tall. I was pulling about 3000 RPM between 65-70. Much better off the line than the original 3.08's, but it pretty much ran out of steam at 70 due to the fact it was a smogged down motor.

 

[squarebodycouple]

Was reading thru this and my old gal is a dog too , but I have no idea what gears are in it , but I have 35 inch tires , 12 bolt rear , 10 bolt front I think...
I’m new here and and mechanically ignorant for lack of a better word.
I don’t think I have any vacuum lines hooked up or where they would even go , but I know it’s got an edelbrock intake and carb do t remember if it’s 2 or 4 barrel , 350 crate motor ( unconfirmed ) no clue what trans or t case but she’s sloooooooooow trans is three spd tho