1985 k5 blazer 305 to 350 motor swap ?
#1
1985 k5 blazer 305 to 350 motor swap ?
i have a 1985 k5 blazer it has a bad 305. i just found a 1991 complete chevy 350 will this motor bolt right up to the transmission with no issues and can i still use all my same parts on it. what will i need to do to it to make this set up work. also this new of 350 is it a 4 bolt block. i believe the guy took it out of his suburban. its complete motor from flywheel to fan. thanks any help is appreciated thanks
#4
It's been a while since I did a motor swap like this. I would set them both on the floor and compare the bellhousing bolt pattern. If they are the same your pretty much good to go. And you may have to swap your induction system to the new motor. The motor mounts should be the same. You will prob have to swap your front accessories over as well.
#5
well if you want to switch out to carb you will need to get a new intake and heads / valve covers to make it work. I am pretty sure that the bell housing should be the same though but you really need to compare the 2.
IT may be easier to convert to TBI ... all you really need is a the harness and the computer for it and the BLazer's system at least on my '87 is very basic.
IT may be easier to convert to TBI ... all you really need is a the harness and the computer for it and the BLazer's system at least on my '87 is very basic.
#6
The older thorttle body motors are really, IMO, not any better than a good, properly tuned carb'd engine. Can be done but why not just put a decent cam in the '305 and use the low end torque to your adavantage?
#7
because it lacks the hp of a 350 and i will need it once i lift it 9 inches and put at least 37's on it. i prefer building a 350 since it makes more sense then to rebuild my 305 and will cost about the same. and as far as making it a tbi its not worth it as my old 88 k5 had injector issues and its common with these engines i hear so carb is a way better set up for me im not worried about mpg as my daily driver is a 2003 dodge ram 1500 with the hemi and a 10 inch lift and 37s and 4:88 gears.
#8
Just get a carb'd manifold for the L05 out of the '91 and call it a day. Everything else should bolt right in. The only other area that there may be differences is in the accessory drive belt arrangement. The '91 will have a single serpentine belt arrangement while your '85 may have the multiple v-groove setup (can't remember exactly when serpentine came into play).
#9
#10
yes this block i just picked up for 50 bucks has the serpintine belt. for those who know chevy its out of a 1991 gmc 1500 4x4. the block numbers are chevy block number 10054727. im not sure if its a 4 bolt or 2 bolt yet i have not pulled hte pan or took off valve covers to identify head casting numbers. this is a complete 1991 motor owner said its orginal motor never been built had 290,000 on the motor before he replaced it he stated it was just old and tired and took all the power to get it up and going. so i assume it needs a over haul ran when pulled. he gave me the stock computor with the engine. just no wiring harness is it worth it for me to go purchase a wiring harness and rewire my 1985 blazer for a fuel injected motor or just rebuild this motor and through an aftermarket manifold on it and a new holly 650 and put an electric fuel pump on the truck since it dose not have the provisions for the mechanical pump. any help and advice woudl be great i just want to have a nice reliable truck. so dont know if i shoudl make it a fuel injected or carb let me know your advice all u k5 owners. i know this tbi unit is known to have injector issues. owner also cut the injector wire harness so its bare wires about a ft out of the tbi unit. let me know thanks
matt
matt