LS1 in a Z71?

[juztyn]

Yes I am still planning on doing the conversion, just having a few ideas about it... say I found a 95-98 Z71 without a motor or tranny (ext cab), would it be any different than my reg cab to do the LS1 swap? would the differential or any of the 4x4 components get in the way? and what about gas mileage, i know z71's with the 350 get like 12-13 mpg, would the ls1 be able to bring this up to maybe 18-19? i know the tires (i would most likely keep it stock though as far as tires or lift) and 4wd affect the mileage alot... im just curious... because ive always wanted a z71, but hesistated because of the mileage. it'd be nice to have the extra space to carry passengers vs. my reg cab, but i dont know. Just hoping i could get some feedback from you guys... and dont worry i am still gonna do the swap either way... Thanks!

[Dark Knight]

The only thing that I can think of that might get in the way is the front diff. A suspension lift can cure that though.

As for MPG, with an LS1 you should be able to at least get in the high teen range if not hit the 20's ever so often..... from what I have been told anyways.

[juztyn]

Hrm a really fast reg cab that gets 22+mpg or a pretty fast z71 ext cab that gets 18+mpg... what a dilema. mainly i am concerned about people space... i dont know, 4wd would be nice but no neccessary, i guess i could get a ext cab 2wd... shoot i dont know i am leaning toward my current truck, but its an idea. I'll have a few months to think on it anyway.

[Hit Man X]

My Z71 gets 16mg city, 20mpg straight freeway. With 4.10:1 gears on 33" tires it'd be even better. Then add headers, ported heads, and a mild cam with the correct volumetric efficiency to the heads and I don't see 22-25mpg out of the question tuned properly.

Ever consider going to an LT1/4 setup on that 350 you have now?

[tomskifi]

hi you must use any of thise oil pans 4.8l 5.3 or 6.0 must be 4x4 ,to clear front axel.what you will do for motor mounts ?gen 3 sbc have difrent maunting. ac system you must cut the frame to fit the compressor .its chalenging and $$ expensive.

[juztyn]

OBS z71s with the 350 and 305 get much worse gas mileage than nbs engines (4.8 and 5.3). incase anybody is new and hasnt been reading my other threads, i have a 96' 4.3 vortec reg. cab 1500 right now, which i am planning on swapping the ls1 to, OR, i was just thinking i would like to swap the ls1 to an obs (incase you dont know what obs means thats old body style fullsize chevy/gmc, years 88-98) 1500 z71, i have a friend who works in insurance and i can get a motorless and and trannyless z71 for a good price. I know I can sell my truck for around $4000 right now. And other than the front diff, i dont think there is much (or any) difference between a 2wd obs 1500 and a 4wd obs 1500 engine swap, correct me if im wrong. As far as ac, probably just forget the ac for now, maybe see if allen decides to box his frame and see how that goes. 4.8/5.3 oil pan is not a problem, thats all you need to clear the front axel? (just because of the diff?? or is the axle beefier on 4wd?) i dont know what you mean about motor mounts, im pretty sure their the same on all 1500's. and the more the merrier on gas mileage, as long as the z71 (IF i decide to go that route) gets 18+ mpg highway, which i dont see as a problem with the ls1, it works for me, if i get more thats great. but like i say i am trying to decide if i want it to go in my reg cab or do i need the extra space and 4wd of the z? whew. that was alot of typing. hope that cleared up some confusion.