V-8 gas mileage

cody77

New member
1050123

hey everyone. i've been doing a little reading on the message board and from a couple different places about swapping a 8 cyl. in my '95 YJ and i think this sounds like the way to go once my four-banger of fury finally peters out on me. well anyways my question is can anyone give me any info on what type of gas mileage i can expect? i'm planning on swapping in something fuel injected like something out of a newer camero or firebird or even possibly a 4.8 or 5.3 vortec out of a truck. and i'm gonna run nothing larger than 35's. any help would be greatly appreciated and feel free to post any opinions.[addsig]
 

1050127

i have a 81 cj with a carburated chevy 350 engine with 35" tires...gas mileage about 12 hwy, 10 city..Plenty of torque..so I would replace the transmission.. It was difficult swapping...I have plenty of loose vaccuum hoses with screws blocking the ends. If you have any specific questions feel free to ask.[addsig]
 
1050154

Id have to say go with a F-body motor, like 305 or 350 tpi.

They have 200hp and 300 ft lbs of torque, nice i must say.

4L60E would be your best bet on a transmission, however, turbo

350's are practically free. When it comes to the t-case,

eliminate the vacuum lines. You can get a dana 300 and

clock it around to the correct position. It shouldnt be hard

at all to find an XJ or TJ with the front D30 without vacuum

disconnects. Youll need an adapter from transmission to t-case

so you might as well get a gear drivin one to beef up.

My 89 camaro 305tpi has 2.73 gears. Yes 2.73's. Strong

gear i guess. The tires are about 26" tall. It gets around

23mpg with 220000 miles. the 700r4 has i think a .73

overdrive, ask around to be sure. Without overdrive like

a th400 or th350 and 3.07 gears (not sure what you have)

Id say youll get around 15-16 mpg with 33's, 35's a little

more obviously. You wont regret the tpi motor, its got

a plenty of power.[addsig]
 
1050173

Has anyone else noticed that BlackBart's icon is of a Toyota Landcruiser? Just kinda thought it odd that a Jeep website would have a FJ-40 as an icon option.[addsig]
 
1050210

if you're planning to do a tpi swap i hope you're wallet is rather deep, its actually cheaper to convert with a carb engine, and then buy the fuel injection conversion kits because then you dont have to worry about as much wiring and the computer and such. I have a 350 with a 4bbl, edlebrock preformer intake, headman headers, and dual exhaust, since im only running 31's, soon to be 33's, im actually getting better gas mileage now then i was with my 2.5L, before i got about 12-15mpg with about 65/35 city/highway, now i get about 15-18 under the same driving conditions, as far as transmission's go i'd go with a TH700R4 because it has a lower 1st gear and is a 4 speed auto, i went with the TH350 for monetary reasons, and overdrive would be nice when driving on the highways but it gets the job done, if you have any other questions about this conversion feel free to ask because i just completed it about a month ago.



Quik[addsig]
 
1050330

ABOUT 13 MPG SOUNDS COOL RUNS FAST

BEST TOGO ALL CHEVY OR ALL FORD ,,, WELL IT WAS CHEEPER FOR ME THAT WAY

AND I HAVE TBI ON A 68 327CI

COOL
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