i picked up a pretty worn out 305 the other day from a previous employer of mine to take to college with me so i can practice machining.It was the block and lower end timing gear and chain, cam shaft and lifters.  I got the idea for this the other day when i was towing a boat down to the lake and i was only able to do 35 up the hill with the pedal to the floor, could i fully machine and rebuild the 305 and put it in my s10 blazer?  i believe it came out of a 1985 blazer but i don't no how to find out if it was carburated or not? does it really matter or is that based on the vehicle that it would be going into?  

Yes you can rebuild the engine and put in your S10 blazer. But it will not just bolt up. I believe theres kits out there you can buy and you'll have to reading into the installation part of the project. Most people just go strait to a 350 when they upgrade the engine in s10 blazers/s10's but I've seen the 305's too just not as common... If the 305 is out of a 1985 Full-Size Blazer then it is carburated.  

would the 350 be a better way to go? i had to do some pretty good damage to get the crank to turn, to get the pistons out and the lifters as well... i had to use a sledge hammer and a steel bar to get the piston out and had to use an air chisel on a couple of the lifters, so i don't know if that would've damaged the block real bad.  

I would not use that motor not that 305s are bad just don’t use that one.  

There is nothing wrong with 305's and if you are going to rebuild it anyway you can bring it back up to spec. Also, there are possibilities with a 305 in that you can use a 400 SB crank and rods in it and bore it .030 over and get a 334 if you want more displacement. with today's fuel prices, the biggest engine possible is not always the best choice because a few less MPG can ad up to a few thousand bucks in extra fuel costs over life of vehicle and no sense in dumping more money down tail pipe than you need too.  

I'd go with a 400 small block or a 327. A 302 Chevy would be my first choice, but they're very rare. Everybody runs 305/350's.  

A 400 SB would be my last choice. The lack of full water jacket cooling due to the use of Siamesed cylinders to get a 4.125 bore in a SB with its bore centers limits proper cooling on engine particularly during periods of high sustained output because cooling of cylinders is not even and then the is very limited head gasket contact area too before you even bore and rebuild one. 400SB do not take kindly to overheating either. While a 400 SB might work okay for short high power bursts, they are not a wise choice in HD apps requiring high sustained output levels. If I needed the displacement, I would use a 383 which is a 350 block with full water jacket cooling and a 400 crank and rods.  

Leave it to SnoMan to pick a 305 over a 400. Why am I not suprised. I've had several and the 400 does not heat. If you're having that problem with one, it's the radiator.

I was just saying I'd go with something different that you don't see every day. That's why I drive a 5.0 powered Bronco II and not a Chevy 400 small block powered Jeep. :-)  

orcus420:
Leave it to SnoMan to pick a 305 over a 400. Why am I not suprised. I've had several and the 400 does not heat. If you're having that problem with one, it's the radiator.

I was just saying I'd go with something different that you don't see every day. That's why I drive a 5.0 powered Bronco II and not a Chevy 400 small block powered Jeep. :-)

Where did I pick a 305 over a 400??? I used to drag race 400 SB long ago and been around a lot of them when they were new and know their limitations well and what fails on them. It is not a engine to ever run hot and lack of full water jacket cause uneven cylinder temps under high sustained load. You would know this if you really knew anything about design. You can have good coolant temp but uneven cylinder temps because lack of full water jackets plus thermal conductivity of cast iron is not that good either. To me a 400 SB is more a novelty that a solid solution in a RV. If I want a 400 in a big GM 4x4, I will use a BB. I owned a few 396's in their prime and even stock they would badly shame a 400SB and will take a terrible beating too. AMC had a 400 too that was based on a similar block size but it had different bore centers which allowed full water jackets with a even bigger bore. The SB was born as a 265 (actual had one of them long ago) and was bored and stroked over the years and it reached it pinnacle at 350 level. Siamesed cylinders to support a bigger bore is a compromise at best and to suggest otherwise is foolish.  

"A 400 SB would be my last choice."

We were weighing in on 305, 327, 350, and 400 small block engines. By saying a 400 would be your last choice, you were saying you would pick a 305 over a 400. See how that works? Nah, probably not.  

Let me put it this way, If I had a 305 and a 400 SB, I would take the crank and rods out of 400SB and put them in 305 and make a 334 (bored .030 over too) To me durability is paramount to me and I like full water jackets. Also, as I have said before, with proper axle ratio yo can do well with even a smaller engine off road. Most that push bigger engine are do not bother to regear axles with lifts or truly understand the significance of it either. These same people tend to think cure is always a bigger motors rather than better gears.  

Lots of hi-po motors don't have full water jackets. It's really not a durability issue. Winston Cup and Pro Stock motors have siamesed cylinders.......  

orcus420:
Lots of hi-po motors don't have full water jackets. It's really not a durability issue. Winston Cup and Pro Stock motors have siamesed cylinders.......

Yes motors with a life expectancy of 3 to 5 hours or a few runs and are torn down regardless between races and cost tens of thousands of dollars to build too and they have spare blocks for when they fail. You want full water jackets if you want a engine to do the long haul under heavy sustained WOT loads and keep coming back for more. To suggest or promote otherwise is wishful thinking and also shows a lack of grasp on the big picture here.  

I give you an example where siamese cylinders run wide open all day long and you still insist they aren't reliable and overheat if used hard.  They rebuild those engines every race because they can, not because they need to.

Let me try to put this is in a way even your limited intellect just might be able to understand. The main heat source in an engine is at the top of each cylinder. The temperatures are NEVER consistent throughout the block on ANY engine. The extra heat in the upper areas between the cylinders of a siamesed block means nothing to reliability. You're just spewing BS as usual.  

You know you really are getting pretty immature here trying to save face. If your theory was so great, they would save money and weight and Siamese all engine cylinders but engineers know that it is not best solution. Also why they is a fair amount of heat in heads because exhaust is routed through them, there is a fair amount in cylinders too and full jacket insure good thermal dissipation and consistent cooling and wall temps so cylinder stays truer because thermal expansion in them is more even plus pistons are more evenly cooled as well because the cylinders cool them. More consistent and lower average cylinder temps also reduces oil be cooked out in rings over time, gumming them up with carbon like deposits. Again you only Siamese cylinders when space and weight is at a premium not when long life is a important factor. Tell you what you go ahead and babel on trying to convince yourself if it makes you feel good because not engine built and designed for serious heavy duty work has anything less than full water jackets. Head run a bit cooler to with full jacket as well because areas between chambers are fully cooled in block and better flow of coolant into head too.