rocketraider

Insert bearings are made of steel with a layer of copper or bronze, and then a layer of Babbitt metal fused to it. That's what the crank rides on with a microscopic film of oil between crank bearing journal and the bearing itself. Idea is the Babbitt metal is sacrificial and will gouge before a metal shaving or dirt damages the crank journal.

Commonly available in standard and .010, .020 and .030 😳 undersize, depending on how bad a journal is damaged or out-of-round. A crank that has been machined should be marked with both main and rod journal sizes, e.g. .010/.010 indicates both journals have been cut .010 under original spec and requires .010 undersize bearings. .010/.020 mains .010 undersize, rods .020. No marking generally indicates a standard diameter crank that needed only polishing.

If you can see the copper or bronze layer when you lift the crank out, that bearing is shot. Just seeing gouge in the babbitt layer isn't quite as bad but will still sometimes mean crank will have to be machined for new bearings.

Sometimes you'll find a bearing that has shifted in its seat and the bearing oil hole is no longer aligned with oil feed hole in the block bearing saddle. This is what is referred to as a "spun" bearing and is generally disastrous. It will announce itself LOUDLY.

Hope I've helped and not confused you too much! Sometimes the concept of "undersize" can be confusing.

Sugar Bear

Honestly only the crank condition and size matter. You won't be reusing the bearings.

If the crank needs only a polish it will need standard size bearings. If the crank needs to be ground and has .010 inch removed it will need bearings that are .010 fatter/thicker to make up for the material ground away.

Are the old bearings ok? That is usually determined by an experienced eye at first, then measured if they pass visual scrutiny. In most cases crank bearings are not reused "just because" if for no other reason.

Good luck!!!

OLDSter Ralph

I was taught that babbit is sorta sacrificial....the soft babbit allows fine particles to embed themselves in the babbit, rather than stay on the bearing surface to gouge the crank.
....Just my two cents worth

64Guy

I was snooping around and found a company on ebay that sells everything I need including starfire pistons in a kit. Like rocket raider said earlier in the theard he used a 60/40 blend of 100LL Airplane gas and 93 octane. I have no issues getting 100LL because my brother is a pilot and he can just get the gas for me. Is the only difference between the Rocket and the Starfire engine the pistons? If so its a no brainer just to throw them in. Also if im going to be running 10.5:1 what is the recommended Ocatne rating I should run?

Charlie Jones

The 93 octane gas should be OK with 10.25 compression .
I drove a '63 Dynamic 88 daily from '97 until '02 with just straight 93 octane .
With 10.5 compression however . you may need 100LL or octane booster .
Here are the different pistons used in 394's ;

OLDSter Ralph

Check out Racetech.com for pistons also.

69CSHC

I couldn't agree more. As someone who has been dealing with subpar gas for over 30 years why make it even more aggravating.

That's super premium territory. 102 octane RON or 97 modern AKI. Race fuel is very expensive and not readily available. Your just giving yourself another headache to worry about. Unless this is going to be a track only car...

64Guy

So the dilemma I'm having is its cheaper to buy starfire pistons in a kit with everything included than it is to get 10.25:1 pistons in a kit. I'm not sure why but its around a $200 difference. Can I not run 93 with a race octane booster to put it at 97 RON? Or could I still do the 60/40 100LL mix?

Charlie Jones

The EGGE pistons are supposedly made in California .
The cheaper ones are probably offshore .

Another thing ; Aviation fuel is not taxed as a motor fuel .
Don't let anyone see you putting it in your car .

Schurkey

You had better check the compression height on any aftermarket pistons you buy.

It is REAL easy to get "short" pistons that destroy quench and reduce compression ratio.

69CSHC

Ahh I see now, you can always detune the engine to get by on cheaper gas...

Your going to need plenty of booster or a very good one to get 93 AKI to around 97 AKI. Guys at the track advised me not to waste time with readily available boosters like I generally use. And rather deal with Summit or Jegs, unfortunately cant remember brand they recommended right now. Although I did write it down somewhere... It may have been either Royal Purple or Torco.

Schurkey

By the time you get done screwing around with fuel additives, lack of range, and the pain-in-the-*** of perpetually mixing your own fuel, $200 for more-suitable pistons is going to seem cheap.

Better to end up with custom pistons, tight quench, and ~9.5:1 compression, than to kill power and economy by having poor spark advance or having to mix custom gasoline.

matt69olds

I would have to agree with buying the better/correct pistons.

I look at it like this, my old iron is my therapy. I enjoy driving them. I don’t want to be 20 miles northeast of nowhere and need fuel, and can’t find high enough octane. And I don’t know how much the octane booster stuff costs or how long a bottle lasts, but I’m guessing it won’t take long to spend a couple hundred bucks in AV gas or booster or run the engine correctly.

Bite the billet, buy the pistons you need. If you can’t find what you need, custom pistons aren’t terribly expensive compared the the total cost of a proper overhaul.

This is a perfect example of the old saying “There is never money to do it right, where will you find the money to do it again?

Anther option you might consider is E85. I don’t know much about the 394 engines, if a fuel pump is available that is E85 compatible I’d consider upgrading the fuel lines and having the carb rebuilt (once again, I have no clue is that’s even an option for a 394 carb) with E85 in mind. If it’s not a option to make the switch, to E85, I’m wondering if a premium fuel/E85 blend might work? The octane rating of E85 is much higher than even race gas, so I would think a couple gallons might raise the octane average enough. The ideal air/fuel ration of E85 is much richer than gas so all things being equal the carb fuel curve needs richened up. Just an idea.

Schurkey

The problem with E-85 is that it's not E-85.

What's SOLD at the pump as "E-85" ranges from 60% Ethanol, 40% gasoline, to 85% Ethanol, 15% gasoline. Vehicles intended to use this have a sensor to determine the alcohol content, and automatically adjust the mixture. It would be near impossible to do this with a carburetor. You'd have to re-jet every season, maybe every tankful.

matt69olds

That makes sense. I’m not up to date on the E85 science.

The years I did drag week the turbo LS guys in our group had little “chemistry sets” that reminded me of the test kits to test pool water samples. They would test a fuel sample at each fuel stop, whenever they found a station with a “good fuel” (whatever that meant to them) they would fill every fuel jug at that station. Since my Olds was the fuel economy king (14 mpg towing the U-Haul trailer, with a 20 gallon tank) I was “lucky” enough to haul about 20 5 gallon jugs of fuel. Since the group I was with all had fuel cells with about 10-12 gallon capacity, we made lots of fuel stops! I assumed (but didn’t question at the time) that E85 had to be a MINIMUM of 85%ethanol.

Im not a fuel expert, so maybe this is a stupid question. Could a couple gallons of E85 raise the octane average enough (and not screw up the tune calibration) to get by if good enough regular fuel isn’t available?

In my area, 93 octane is easily found. However, after reading this thread I’m finding out that in some areas 91 is about the best that can be found.

Like I said, this may be a stupid question.

Fun71

I don't know about the octane part of your question, but I have used up to 25% E-85 mixed with "regular" gasoline without incurring any drivability issues during warm weather. I noticed when I did this in cooler weather the engine did not run very well.

matt69olds

I figured if it was a option, everyone would know about it and be doing it. Of course that would be too easy a solution!

Having said that, I figured the engine would run on E85. I’d be willing to bet that’s a concern the refineries and automakers anticipated long ago. I’m sure everyone reading this can think of someone who is so cheap to put ANYTHING from the gas pump into their car if it was cheaper. You can imagine someone pulling up to the gas pump with 5 bucks in their pocket thinking “this gas is 50 cents cheaper, more cigarette money!” That’s probably the biggest reason diesel nozzles won’t fit into a gas tank filler.

64Guy

Hey Guys! Soon in the next week or so ill be bringing the motor to a machine shop. Many pictures to come. Does anyone have Oldsmobile 394 measurement specifications? I'm trying to find cam lobe diameter and some other miscellaneous engine measurements.

Charlie Jones

The 1963 Oldsmobile Service Manual has everything you need .
Get one and loan it to the machinist ;
1963 oldsmobile service manual | eBay

64Guy

okay great! I bought a 64 book reprinted. Also I couldn't find any identifying marks on the connecting rods to know which way the caps go on. As well as main bearing for order. I believe there right but I wanna make sure of course its correct. So here are some miscellaneous questions:

1. Is there marks on the connecting rods to put the cap on the right direction?
2. is there markings on the main bearing caps for order?
3. Are the heads identical or do they have to go on the correct side?

Schurkey

They'll be non-symmetrical. One side will have extra clearance for the crank journal fillet. And you can also judge by the bearing tang notches.
Probably not--until you mark them.
They may be identical castings--I don't know for sure. They may be different in terms of coolant outlet fittings or some other details. Probably best to put them on the same side they are now.

rocketraider

Use a ***** punch or a set of numerical stamps to mark the rods and bearing caps i.e. 1 dot or 1 for #1 rod, 3 dots or 3 for #3, etc. Mark rods on both sides of the bearing split so everything stays together.

Keep in mind Olds pistons are numbered front of engine to back 1,3,5,7 on driver side and 2,4,6,8 passenger side. Main caps 1 at front of engine, 5 at the back.

Heads work on either side but it's customary to put the head with the engine # stamps on the driver side as the factory did.

Charlie Jones

Caps 1 thru 4 have numbers cast in on side .
#5 is obvious .

64Guy

Iv decided to go full ***** to the wall and do the rebuild the correct way. The machine shop is doing a ton of stuff to make the motor like new. Everything will be new except crank, heads, valves and connecting rods. I will also be sending the rockers out to Rocker Arms Unlimited in California to be rebuilt and I will be getting a new cam. Here is a picture of what the machine shop will be doing for me. This isn't set in stone but its basically an outline. Cheers!!

Schurkey

1. Knurling guides is 1940s/1950s technology. DON'T LET THEM DO THAT. Have bronze guide inserts (liners) installed. Are they sure they can save the valves? If they machine the seats, you're running the risk of seat wear--the work-hardened layer is cut away, exposing the soft parent metal below. Consider hardened exhaust seat inserts.
2. Stay the hell away from Mondello. First Guess: "Len" at Mondello is really Lynn at Mondello, and you're going to hear a hundred horror stories about him in about two hours.
3. Be VERY CAREFUL with the compression height of your new pistons. Lots of cheap pistons are made "short" (low compression height, sometimes called "Destroked"). This will kill your in-cylinder turbulence leading to detonation and needing lots of ignition advance. Find out how thick the head gaskets are going to be, and deck the block accordingly so that the quench distance is reasonable--not over .045 and likely less. If you buy short pistons, you'll have to have even more taken off the decks. You could run into problems getting the intake manifold to fit properly.
4. I don't see any charge for align-hone of the main bearing saddles. Are they at least going to check them?
5. Pay extra to have this balanced. Make sure they check the flywheel and damper individually so you know they're balanced properly before they start drilling the crank.
6. When they're installing the "plugs", make sure they know where they all go. A Genuine GM shop manual will be essential. Not many engines get core plugs shoved into the block decks, but the first-Gen Olds is one of them.

64Guy

1. I wont know if the valves are good until they disassemble the heads. If this is not a good idea then I will not have them do it. Would i just get new guides then?
2. The gentlemen at the shop spoke very highly about Mondello. If I cant use them do you have recommendations for cam and bearings?
3. I haven't looked into pistons quite yet. I know eddge makes great pistons but again if you have an Oldsmobile website that have pistons let me know.
4. Its not on this sheet but yes I gave them the mains to do a align-hone on the mains.
5. Im not sure what you mean by balanced. The are going to polish and then balance the crank.
6. They showed me 2 other disassembled 371s they they did plugs on. I have no reason to believe that will be an issue.

OLDSter Ralph

Schurkey pretty much hit the nail on the head.
2. If they speak highly of Mondello in Pasa Robles, California, Go get your parts and find another shop !!!!!!!
3. Try www.Racetecpistons.com (714) 903-4362 also.
6. I wouldn't be impressed with two disassembled engines. Have them tell you who has Olds engines they have done and are still running.

matt69olds

If he speaks highly of Mondello in California, chances are good he hasn’t done business with them in about 20 years.

Charlie Jones

I have a set of eight new exhaust valves I bought from Fusick .
1962-64 Olds 394 V8 exhaust valve-Fusick Automotive Products, Inc.
$135 including shipping .
PM me if interested .

64Guy

Okay. Thank you for all the suggestions. I think ill have the machining done but then buy my own parts from reputable dealers. He said to me its probably a good idea to get a new cam as well. Because the lobes like to wear down. Is this true?
1. Can the cam be tested?
2. He also advised in buying adjustable pushrods?
3. Is MAHLE / CLEVITE a good bearing brand? Their through Rockauto
4. Is it even smart to grind down the valves or leave them how they are?
5. Does anyone have good things to say about Egge Pistons? https://egge.com/ They sell Main bearings, cams and just about every other 394 part.
5. Do I need to replace the upper connecting rod bushing or just leave it be?

Charlie Jones

1. The cam can be measured with a micrometer to check for wear .
2. No, adjustable pushrods are not necessary. Especially if the rockers are re-newed and the shafts are replaced .
3. Mahle and Clevite are both good brands .
4. Egge pistons and other parts are of good quality . From everything I have seen .
5. You probably won't have to replace the upper rod bushings . A micrometer will tell you for sure .

64Guy

Thanks. Is it smart to have the vavles grined down? I called them today and said no Vavle grind or Knuraling the guides. What going to happen is he's gonna take out all the vavles. Check for wear/damage, magnaflux it and then bake and blast it. I said I will be reassembling the head to put the new vavle stem seals in. Once its been reassembled then it will go back for a resurfuse.

OLDSter Ralph

1. They are not going to grind the valve head and lap to seal ? Are they grinding the valve stems after assembly ?
2. Who checks for valve guide wear? If the valve guides are worn excessively, you'll need to do something about that.
3. What is being resurfaced after assembly ? Wouldn't you want the head gasket side of the head resurfaced flat before you re-assemble ? Are they grinding the head gasket surface or milling it ?
4. Re-assembly should be the last step.

Charlie Jones

The decision to replace valves , rather than re-grinding them is determined by the wear on the valve . And whether they may have already re-ground .
Also valve stem wear has to be measured .
The outer edge of the valve is known as a " margin " . If this margin becomes too thin it can cause detonation and valve burning .
Generally , if a valve is ground so that less than half of the margin remains , it is cause for replacement .
Hardened valve seats are a good idea on the exhaust only . Unnecessary on the intakes . Because of unleaded gas .
Valve guides can be successfully re-sized by knurling . In fact , this is the only way to do it on a Chevy where they aren't replaceable .
I assume you aren't building a race engine , so re-grinding valves and knurling guides are a perfectly acceptable practice .
Before you have the heads re-surfaced , have them check them with a straightedge . If they are warped less than .002 end to end they may not need re-surface .

Schurkey

Look at the lifters. If any one of the lifters shows wear on the bottom where they ride on the cam--the cam is junk. Lifters generally come out of the engine with a concave wear pattern--the edges have less wear than the center. But they're made so that the center is supposed to be taller than the edges. A good lifter will "rock" on a flat piece of glass (just barely). In other words, the bottom of the lifter is made convex, but wears concave. And if only one lifter out of sixteen is worn...the cam is junk.

Two big problems: Modern lifters can have horrible quality. The Communist Chinese can **** up anything, and they supply a lot of lifters now. And that Olds is likely to have an unpopular size of lifter, making it tough to find good ones.

Not needed if he does his job properly.

Yes.

Almost certainly needed. I bet the guides will be wiped, too. Maybe the valves as well. The issue is that they spent their first 15 years with leaded gasoline, so the fuel had lead to preserve the valve faces and valve seats. The metal was soft, but work-hardened in use. Then the lead was removed from the gasoline. But the valves and seats were work-hardened by then. Now you cut the work-hardened layer away, but there's still no lead in the gasoline. So soft metal can wear away, ruining the valve seats. You may need hardened inserts put into the exhaust seats.

Be VERY CAREFUL. ASK them about the compression height. Ask them about the piston-to-piston weight variation.

"I" would not consider them. I'd have custom pistons made, or I'd find something more modern from some other engine that happens to fit (not likely, but possible.)

Tell your machinist to measure them, and inspect for wear. The machinist is going to be checking the rods for proper sizing of the big-ends, he should check the small end while he's holding them in his hand anyway.

That's crazy.

Yup.

If the guides need work, the valve seats will have to be remachined, not "lapped". If the seats have wear (likely) then lapping won't be enough to fix them--they'll have to be machined. And if they have to be machined, the exhaust seats should get hardened inserts.

Thank you.
Absolutely not. Knurling guides is a short-term solution. A better, longer-lasting solution is to bore/ream the original guides (including the guides on a Chevy) and then fit thin-wall bronze inserts. The bronze inserts are then honed to size. The original guides aren't removed, just opened-up on the ID to fit the bronze liners.

The heads need to be FLAT and SMOOTH. If they are, they don't need to be machined. If they're flat but not smooth, or smooth but not flat...they get shaved.

How "smooth" they need to be is determined by the head gasket. Steel shim, and multilayer steel gaskets need a very smooth finish. Composition gaskets can get by with a less-smooth finish. I'd expect the engine was originally built with steel shim head gaskets, but I could be wrong--and steel shim gaskets in general are hard to come by for any engine that isn't a BBC or SBC.

64Guy

I got the heads back today after they were blasted, there looking very good. The reason my machinist said to get adjustable push rods is because the rocker arm assembly I sent in may on some rockers go in deeper than others? is this true?

64Guy

I have a few questions I need help with.
1. Is Mondello really as bad as some say?
2. Can I use a old cam with new bearings? where can I buy cam bearings for the 394?
3. With pistons my machinist said we can have them custom made but i fell it would be easier to just order them through Egge. What do I need to ask them?
4. Should I buy new pushrods if I'm having the rockers rebuilt?
6. if they hoan the lifter bores do I need new lifters?

OLDSter Ralph

Charlie Jones

1. The Mondello to shy away from is in Paso Robles CA . Bernard Mondello is OK .
2. Can you post pics of the cam ?
Did you make sure to identify each lifter , when you took it apart, as to witch lobe it ran on ?
.New cam bearings are on E-Bay , or from Egge .
3. I had custom made forged pistons that cost over $750 for my 394 . But I plan on drag racing it once in a while .
But on a car that is just driven to cruises , and to take the kids for ice cream . Egge pistons will do just fine .
And you will have an extra $300 for ice cream .
Egge will only need to know what size overbore you need . Your machinist will determine that .
4. Pushrods are cheap . Buy new ones. You don't need adjustables if your machinist knows what he's doing .
Make sure to get new rocker shafts . Fusick has them .
Rocker arm shaft, 1960-64 Oldsmobile 371, 394 V8-Fusick Automotive Products, Inc.
6.As Ralph said "why are they honing the lifter bores ?
If you put two lifters together , bottom to bottom , and you can't see daylight between them when you hold them up to the light .
Then they are worn out and so probably is the cam .

64Guy

So I need an honest opinion. It is more expensive to make or buy customs pistons to decrease the compression to 9:1 than it is to buy the 10.25:1 pistons for the 394. Is there anyway to run 10.25:1 today? Our highest premium gas in town is 93 octane.