Running Buick 350 for $750, Supposedly Good Compression and Oil Pressure

I would not use the 1746 kB pistons. At .90-.100 below deck , compression will be around 7.7 vs the stock SP pistons at about 9.2.
Pull head, turn crank to zero on timing mark, put straight edge over #1 cylinder, and use feeler gauge to measure piston depth. Should be about.060 below deck on an SP engine.
Get new valve springs. 50 year old stuff is worn out.
You will need a ring compressor tool to put in pistons . And when removing and install rods, get a some vacuum hose or old spark plug boots on rod bolt ends so not to scratch crank . Factor in a rebuild on balancer. Damper dudes can do that, possibly cheaper then new. Again, 50 year old stuff.

 

Got it, so a machine shop has to be involved either way . . . and might as well let them do the boring and honing while I'm at it. Then align hone. Then deck. ect ect.

I guess the home rebuild is a myth haha, or at least not really worth it.

OK I've made up my mind. I'm going to get a machine shop to the the machine work!

Now I have to decide if I should rebuild the SP 350, the blue block 350 (don't now the year) I bought for parts that has terrible leak-down specs . . . or the 76 AF 455 block that still has crosshatch in the bores and only had 1 cylinder with low leak-down. Pics of that block here:

http://www.v8buick.com/index.php?threads/455-core-block-bore-pictures.334519/

I will be posting my "machine shop flow-chart and instructions" later tonight so you guys can tell me if I know what I'm getting myself into or not.

In the meantime, I'm going to offer that guy $500 and if he says yes then just throw that 350 in my car for the time being so I can at least drive the damn thing again.

 

To do a refresh/re-ring, you re-use the factory pistons! So - $220. The thing that makes the "SP" sbb 350 any good is the factory pistons! The non-SP sbb 350 engines have pistons with bigger dish volume and or are deeper in the hole to reduce compression.

If you really want to cheap out, do a repair by removing the number 7 and 8 pistons and if they aren't cracked or damaged in any way, buy only 2 single sets of rings and ball hone just those 2 cylinders with engine still in car. Leave timing cover on, keep same cam if it ran ok before.

Before you remove the 2 pistons, use scotch-brite with brake clean on it to scrub off the carbon ring at the top of bore so the pistons will remove easily. Of coarse the oil pan will need to be removed with engine in car but is doable.

Make sure to wrap the crank's exposed rod journal with a rag and tape it in place and rotate the crank so that rod journal is as far away from the block as it can go before ball honing and cover everything at the top of engine to keep ball hone grit oil that may splash out of engine.

When ball honing, you only need to go down to where the rings make contact with cylinder so you keep the hone away from the crank. You'll be able to see where the rings stop making contact at the bottom of the cylinders.

After ball honed use the brake clean to spray out the ball hone oil and grit out of cylinders, then use a white paper towel with brake clean on it to wipe cylinders out until the paper towel comes out without any discoloration on it. I usually will take 2 paper towels stacked on each other then fold twice into a square so you'll have 4 clean areas to wipe the cylinders out with.

Make sure to spray out the bottom of the block with brake clean to get any of the grit oil out of inside of block as well.

Clean piston grooves and the rest of the piston, re-install new rings, I like to dip piston in 20w/50 oil up to the wrist pin drain off excess and wipe off top of piston with finger, then compress rings and install piston into lightly oiled cylinder.

This repair will be the least expensive and fastest to get you back up and running. While the heads are off you might want to have them gone through with a valve job. Waiting for the heads will be the longest part of the job, the rest of the job can be done in a weekend taking your time.

Cost for a repair like this will be the cost of new head, oil pan and intake gaskets, 2 single piston sets of rings, a can or 2 of brake clean, a roll of paper towel, a quart of 20w/5, a valve job and however many beers it takes to get it done.

You can reuse the rod bearings if they don't look to bad or buy 2 single sets the same size that came out.

This whole repair will probably cost under $150(not counting cost of beer) and a weekend of work for the short block repair. The valve job would be another around $200 depending on local machine shop pricing. Seeing how you were having pinging problems, if you get the lessor expensive Fel-Pro head gaskets, they should get the compression down just a touch to stay away from the pinging.

Seeing how this isn't the "right" way to do this according to some, it won't cost much to do if it doesn't work out but more than likely will be just fine. Dealers choice, $750 for an underpowered smog era engine or $350 to repair what you have.GL

 

Damn Derek stop making me change my mind!!

Ok, you make a pretty good argument for throwing $350 at the motor and seeing what happens. I may just try it. However, I think I will pull the motor because a. I have a hoist and b. it will be mush easier to work on the engine. I may replace a few other gaskets and such as well, plus I need to replace that freeze plug behind the motor mount anyways! I may be 6'2" but I'm actually a super lightweight, so a single 6 pack will probably get me through the entire process

 

Yeah, if it doesn't work out, you'll have a fresh set of heads for the other 350 if it is still for sale. So you would only be out the $150 and the 6 pack!

 

I'm not kidding.

 

Whoa you're not! Was the car in a barn or something? How does that happen???

When I bought my Lincoln, I found a mousetrap in between the transmission and the floor pan, a first for me!

 

The engine was on a wooden cradle in a finished basement when I got it. It was complete, less carb. One of those houses half built on a hill so the basement was also a garage. Doubt it happened in there, but it sat for over 20 years, anything is possible. It still ahd oil in it too, i think they just used it for storage. They also stacked little carbon flakes in all the ports for some reason. They're crafty. Always check an engine before firing it if you have the chance. Thing would've destroyed itself if i dropped it in as it was like I was planning to.

 

Any updates?

 

RUN, RUN very fast.

 

Nothing yet sadly, I'm leaving the engine in the car for another month or so, so I can mock up something else But I will hopefully have the engine out and "refreshed" soon! I will for sure post when I do!

What am I supposed to be running from??

 

Location drives Price. i.e. Sacramento.

 

Mr S, no mice were ever in that exh port. That seems to be pure sign of neglect, corrosion, and just plain rust.
Maybe that's what Steve was referring to when he saw that pic and mentioned to run.

 

Si Senor.

 

I would do all new rings and bearings of the same size. Hone the cylinders, clean out the screen, good head job , stick it back in as far as it will go and see what happens.

I had a 4.0 jeep that had a REALLY screwed up crank. It looked like it had starved for oil and spun one of the bearings in the block. Didn't hurt the block, and wasn't seized to the crank. The tabs on the bearing were gone, and you could see that it just used whichever place it wanted to turn. I just put new rod and crank bearings in and drove for another 100k while pulling a camper as well. It's still driving around today.

 

Is it really worth it to disturb the cylinders that have good compression? I feel like honing 2 cylinders and replacing 2 rod bearings with the crank still in would be less stressful than tackling all 8 and taking out the crank . . . but I've never done this before.

So I'll come clean and say what I'm really up to, though I held back until now because I didn't want to be bashed for trying to cheap out on the engine haha . . . I recently acquired one of Mark Burton's Twin Turbo Kits plus downpipes for Skylark for a really good deal from a fellow board member. This was always my dream, so I didn't have any trouble convincing myself that it was worth it! This is partially why I don't have a lot of money left for important things like an engine rebuild

Now, I know that I want to "correctly" build either the 455 or 350 spare block(s) sitting in my garage in the future to handle mild boost. To me that means forged (autotech) pistons and ARP studded or better rods and something like 9:1 static. Maybe girdle if 455. But that's $3000 - $6000 and several years into the future.

My plan now is to effectively "slap" the turbo kit onto a running 350, add a Scoot Brown cam, perform a general "refresh" of gaskets, timing set, front cam bearing etc. and drive like that for a while on 6 to 8 psi. So I can either home hone my current SP motor to make it into a running (i.e. not oil burning) 350 or find a used but good motor like the one from Craigslist. Oh and I was able to snag a meth/water injection kit for 50% off (SEMA special pricing) from Devilsown, that will hopefully add extra safety.

If I end up grenading a home rebuilt 350 motor then so be it, I'll still be happy that I tried and will still have the turbo kit to try again with an actual rebuilt motor.

Last weekend I started on the exhaust manifold bolts so that I could mock up the turbo kit with the engine still in the car before I pull it out to either replace it or hone it. I am tackling small but necessary things like removing the AC components and replacing with a delete box, and switching to smaller brake booster (both of these things to clear the downpipes). Going to mount the turbo manifold, turbos, and wasetgates so I can build the cold side out of mild steel. Slow slow progress but at least I'm wrenching toward something. After that is mocked up I will yank the engine out and decide what to do with it.

 

If I were in your position, Id do what your doing now, mock everything up, and while doing that it will give you time to contemplate how/what your going to do with the engine.
Focus on the rotating assy. and oiling.
Theres nothing worse than a rod or main bearing starting to make noise.

 

I hope you know how to tune a turbo system, it isn't just a slap on and run 6 lbs of boost and think it is going to run correctly. You better do all the oil mods if you want to go that route. But then again it may live longer than we think, It will be a good test.

 

That's the plan! I'm not in a rush so I'm going to take it slow.

I hope so too haha! Oiling mods will be done, or as much of them as I can do myself. I've read through Jim Weise's thread on them and seems like I can tackle most of it. I'm secretly hoping to go self tuning EFI that controls timing and AFR but will probably start with a cheap used Holly with Hanger18 mods and see what happens. EFI seems like the way to go but costs the same as it would to get machining done on an engine . . .

I have put up my other car (1977 Lincoln) for sale. If that sells, then I will have a much better budget for the Skylark which will really accelerate this plan. Hopefully someone buys it!

 

It will live longer than you think. I did main studs and rod studs. Years later it's still running in Arizona and making people smile. No oil mods, just a good TA front cover and their blueprinted oil pump. The springs in the wastegates were 8lbs, but the boost gauge often said 12lbs. Ran it for a long time on hypers. Kind of wish I had never changed that.