Engine Rebuild Kit Recommendations

[kalger]

I'm looking for a recommendation for an engine rebuild kit for my 1975 GMC 1/2 ton PU with the 5.7 350 engine. Any information would be very much appreciated.

Thanks.

 

[fast 99]

If doing a re-ring just buy rebuilder parts but do not get a reground cam, new only. Probably cheapest place will be rock auto. Would opt for a 1-piece pan gasket and higher quality valve cover gaskets if available.

You will need to inspect everything before buying anything. Last time I tried a re-ring the motor was beyond that sort of repair. Was able to save 6 rods and the block, rest was junk.

 

[JKRamsey1991]

I am currently buttoning up the rebuild on my small block. I found it was cheaper to piece together a the stuff than buy a kit if doing a simple re ring and bearings for me. I wanted to upgrade a few of the parts like oil pump and stuff and it equaled out to me saving money over buying the kit to just get everything at once.

 

[GTX63]

I noticed in your OP you didn't mention price. Good for you. Rather than tout one or two companies, folks behind me will do that, I'll mention where not to buy a kit-ebay.
Lots of buyers are finding out that Chinese rebuild kits made with eyeball micrometers are nothing more than junk. Motors that won't spin freely even before completely assembled, new bolts snapping off, gaskets that won't line up, poor matierals, etc.
There are also increasing issues with camshafts not even making it thru the break in period before going flat.
I'm not saying you have to spend a ton of money or buy from the very best, but go with a longstanding seller with a name and reputation to back up their products.

 

[dvdswan]

Depending on how much you are willing to spend or make your budget. Find yourself a reputable machine shop that has done work for race hobbyists. Have the block cleaned/vatted, balance the engine, among lots of other little things. Some will say this not necessary, but I assure you little things do matter when rebuilding an engine.

 

[Radiohead]

It's all the little things that make or break your rebuild.

 

[Ricko1966]

We rebuilt or did the machine work for diy engines,at least 1000 a year I never documented it,but I'll bet less than 1 percent got balanced I don't remember a single issue with an unbalanced engine coming back I can't remember anyone who built their own coming back and asking us why there was a vibration.Not saying it's a bad Idea I balanced most of my own because it was no cost,but balance vs. Funds vs. What's most important balance would be the least of my worries. If you are running you're crank,your rods,your pistons or a matched set of decent quality your balance won't be any worse than a new target motor.

 

[Craig Nedrow]

Like Rick, I to balance all my engines, and glad I do, cause a couple would be shakers, mostly ol' 235's. Rick is right, if you can do it, mostly it becomes a problem at high rpm's, if you were out 4 grams or so. Most assemblies from the factory that I have checked are within a couple grams, close enough. You COULD static balance it yourself, with a scale that has a resolution of .01 grams or even .05 g. I have replaced one piston a few times, and no problems, drove for many years.

 

[kalger]

Thanks all for the comments and suggestions. I will reach out to a local engine shop and see the price for all of the machine work. I might just go with an engine replacement to save some headaches.

 

[Peter coppola]

I am looking for advice. I restored and assembled my first SBC last (305 V8 for my son's IROC). I went to a machine shop, motor, pistons, rods and crank were good so machine cleaned everything, honed block, installd cam bearings, core plugs, oil galley plugs, valve job and polished crank. They purchased all parts except cam & lifters ( I bought a COMP cams rv cAM). I took my time and reassembled myself and it worked out good. Motor runs good and no leaks. I have about $1500 in the motor between parts and machine shop work (plus my free time as a hobby).

I had picked up a 79 K20 Parts truck that had a running but tired 4 bolt main 350. I needed parts for my project so this was a "free" 350 core.

I disassembled with the intent that I was going to do a backyard refresh with fresh bearings, rings and reuse the 305 cam & lifters as they were good, but got replaced with the RV cam.

So I cleaned everything. I bought STANDARD size bearings and rings. I installed new cam bearings myself and coreplugs.

I installed the crank this weekend and that was fine. I used a three stone hone tool to deglaze the cylinders and that went OK. There is slight ring ridge at the top of the cylinder but I was not too concerned as this is not a race motor. I just wanted to throw it together and wait for a beater project to present itself.

So, now I am installing the pistons and they are tight in the honed cylinders. I checked the rings and they are standard and compared the dimension of new rings/oil wipers to the old rings/oil wipers. They are identical. I even installed an old ring set on one cylinder and the old rings are pretty tight.

The gaps on the rings are around 0.016. Called Enginetech (ring manufacturer) and they confirmed ring it is right for my motor (no issue with deep vs shallow oil control ring).

I do not recall when I assembled the 305 that the pistons were this tight. Two knocks with a wood handle and they went right it.

I put 6 pistons in and the crank turn is snug but doable. With 7 and 8, I am losing confidence.

Did I cause a problem by doing a DIY hone> I know I had to break the glaze or the new rings won't seat.

I want to see the project throuigh but don't want to ruin a good core just "to see what happens".

Any guidance/experience is appreciated.

 

[JKRamsey1991]

I would get out some calipers/mics and really start measuring everything. It its really tight something is most likely wrong. Make sure the ring depth on the pistons matches the ring spec. I know you can get different oil ring groove depths 0.200 vs 0.165 i believe that may cause an issue but should be able to confirm by accurately measuring the rings.

 

[Craig Nedrow]

Different piston types require different clearance spec. Hypereutectic are probably what you have, and are a snug fit, .0015-.0025 common for a 4" bore. Hone finishing usually 400 grit stone, you can scotch brite to act like a plateau hone, up and down, not circular pattern. Ring clearance for this non turbo/nitrous motor should be around .02, measure 1" down and square in the bore. Use a feeler gauge.