Highway MPG

[Mr. Land Yacht]

Since I have the 3.55 gears, my highway fuel economy suffers(obviously).
here's what I was wondering...
what if I were to put bigger wheels/tires in the back, just for the highway driving? so that I could get more like 23-25mpg instead of 21.7mpg...just for long highway trips.
I could always swap the wheels at the dragstrip/destination...right?

if I did this, what size rims/tires should I get? 16's? 17's?
I'd prolly just get the cheapest wheels I could find like black steelies or something.

I'm pretty sure I saw someone on here that had a box mgm in white with LX Sport wheels, big tires and 2.73s...he got like 29mpg hwy or something...

any ideas?

-Colin

[Mr. Land Yacht]

ah...what size tires should I get?
BTW, Dave, I like the new Avatar!

also, is the speedo gear and odometer gear seperate?

[Nathan in MI]

also, is the speedo gear and odometer gear seperate?

No, the speedo and odo are one assembly. And changing to larger diameter tires will screw with the speedometer accuracy.

[Mr. Land Yacht]

ic...but I can always have a friend ride next to me so I can figure out what the actual speeds are..that's no problem.
I've been driving like that since I changed to 3.55s Im lazy.
but I got paid today, so I should order that speedo gear...

[Archangel]

dunno about 29mpg, but 28 is possible, I pulled that on a summer road trip fully equipped with the large scoop and the redneck Continental kit, rolling on 25" wheels (245/60-15 tires on steelies) and a 3.08 rear end, loaded with full tank of gas, 3 mountain bikes, and a shitload of camping gear. And yes, that is the number after recalculating for the smaller than stock wheels, before that it was something over 30mpg. Then again, I just rolled down the Big Mack till I hit 55mph, set the cruise on, and never touched a pedal for the next few hours, even the big rigs that were at the show in St. Ignace were passing me, lol

Actually if you pull 29mpg with the large wheels that means that your fuel economy is even better, as due to the larger wheels you'd have actually traveled more distance than yer odometer registered, it's the smaller wheels that overestimate the gas mileage, not the big ones.

[Tiggie]

If you are on the cheap, 15in wheels (your old turbines?) would be easist to find. Plop a P235/75-R15 (common size and cheap) on there and that will help turn your 3.55's into about 3.27's.

[OVERKILL]

If you are on the cheap, 15in wheels (your old turbines?) would be easist to find. Plop a P235/75-R15 (common size and cheap) on there and that will help turn your 3.55's into about 3.27's.

That's a good suggestion! With the 3.27's I get ~25mpg regularly.

[gadget73]

I want to go wide ratio with a 3.27, but thats down the line a ways.

[Archangel]

If you are on the cheap, 15in wheels (your old turbines?) would be easist to find. Plop a P235/75-R15 (common size and cheap) on there and that will help turn your 3.55's into about 3.27's.

Wonder what gearing my setup equals to now, with 3.08s and 235/75-15s...

[ss_mini14]

i cant tell what my fuel mileage is, my speedo and odometer is around 10% off. either someone installed 3.90 gears in my rear end or the transmission has been replaced with one intended for a 3.27 rear end. the axle code is "K" (i smell a hot rod wagon brewing).i'm sure it's not more than 18 in the city, probably less because i always have my foot in it. i love the acceleration though and wouldn't drop a higher gear in if i had to. if only i could drop it into 2nd gear manually...

[Nathan in MI]

If the axle code is "K", that means it's a 3.55 trac-lock, at least originally. As far as I know, that means you need a 20 tooth speedo gear.

[Archangel]

18mpg city is awesome, especially for a wagon. Also the 4-spd trannies from that time are all the same, so it really doesn't matter what the rear gears are you still have the same tranny as everyone else here.

[Tiggie]

Wonder what gearing my setup equals to now, with 3.08s and 235/75-15s...

About a 2.86.

[Archangel]

About a 2.86.

Which would explain why as long as I keep the tranny in "D" and take my time accelerating the car cruises really nice around town.

[ss_mini14]

now that i think about it 18 is wishfull thinking even on the interstate in overdrive. the 125 mile round trip to get my kids for the weekend uses about half a tank which to top off from the low fuel light is about 15 gallons or so. that would be about 7.5 gallons for 125 miles or about 16 2/3 mpg. probably less as i'm not including driving around town. i still wont give up the low rear end, tonight i showed a cocky kid in a neon how to drive on the freeway. i was in the hammer lane doing around 70, passing this kid so i could get in front of him and pass the snowbird going 60-something in my lane. the kid heard me hit the gas in OD (via the hole in the right muffler) and sped up to block me. OK no big deal, i dropped a gear got behind him, then passed him on the right with no problem as his fart-can exhaust made it known that he was trying to catch up. i love fourbangers but i'd never take one up against anything with an american V8, especially with nothing more than a fart can to make it sound fast.