My son and I did a trial assembly on the 331 today trying to make sure everything is ok before we send this stuff out for balancing. We had to clearance the block for the h-beam rods. The rod side clearance measured between .022 - .024, Does anyone think this is going to be too much? I can probably juggle the rods and get it .023 max but it's a far cry from the .015 I was hoping for.
The piston to deck clearance is .026 down in the hole on the left bank and .024-.027 in the hole on the right bank. I'm thinking I'll have the shop cut it to zero and go with .038 gaskets, or should I run it as is with a .015 or .018 steel shim gasket?

The side clearance is fine.
On the deck either way is fine. You can run it with a 1094 felpro or have it zero decked & come up with almost the same thing with the .039.

Ive ran as much as 030 side clearance and never had a problem On head gaskets try felpro 1003gasket bore 4.166" nominal thickness .041" comp volume 9.1cc

Mike, my machinist and I decided to get the side clearances down to .015 ( and he could since he remachined the crank and rods, or so he says). This is one of the reason I decided for the oil bleed solid lifters.

Pros/cons of running a 'tight' .015" side clearance? Just curious as to your opinion. I did tell him I wanted a tight motor to run 50K miles, NOT another loose L88!

IMHO .022" of side clearance is fine. It won't cause any problems, and won't be the thing that takes it off the road. I certainly wouldn't spend extra money to build up the rods.

I would however zero-deck the block rather than using the thin gasket. The metal parts move enough over the course of their temp changes and what have you, that thin gaskets are a weak point. The regular 1010 is the way to go,or a 7733-PT9 set.

Thanks for the input so far, this started as a budget build for my son's nova but we've got a sizable investment in it so far. I think I'll have the block zero decked since it is original and does show .003 of warpage with a straight edge and feeler guages. Anybody know of a .035 or .038 gasket with a round shape bore of 4.03 or 4.06?
We'll be running a basic Melling High Volume pump that came with two optional springs. I'm thinking we should use the high pressure spring to make sure the rods have lube at all times with the wide side clearance. Originally I was going to use the standard pressure spring.
Any thoughts as to whether the wide side clearance will need thicker oil? Bob

Use the 1010 gasket. .039" IIRC, don't worry about the bore diameter, it's simply the correct gasket for the application at hand.

I would not use a HV oil pump. Side clearance or no, it isn't necessary in a motor with a stock oil system, and will do more harm than good, in distributor gear wear and spark scatter and lost HP to drive it. I'd recommend a regular M55, with the Mr Gasket #26 spring in it, and a Melling IS-55E drive rod with a steel sleeve.

I'd build it to normal stock bearing clearances, like .0015" on the rods and .002" on the mains, and run normal motor oil in it, like synthetic 10W-30 (though I'd use regular mineral oil for break-in of course).

I think you're getting all worked up over nothing about the side clearance. It's really a non-issue.

Originally posted by baddbob71:
My son and I did a trial assembly on the 331 today trying to make sure everything is ok before we send this stuff out for balancing. We had to clearance the block for the h-beam rods. The rod side clearance measured between .022 - .024, Does anyone think this is going to be too much? I can probably juggle the rods and get it .023 max but it's a far cry from the .015 I was hoping for.
I ended up with about .017" side clearance on my 331. Didn't have any problems.

Skip the Melling high volume pump. I installed one and later regretted it. I posted about it some time last year. In a nutshell, I would lose oil pressure at 4800 rpm. Pulled the engine, installed a standard pump with the Z-28 spring, great oil pressure to 6,000+

Have fun!

Mike

When you get the deck done, make sure it is referenced off the crank centerline and not the pan rails. Some shops do this assuming the rails are parallel with the crank. This is not always the case.

I'm running .022-.024" rod side clearance. I'm using a M55 stock pump and take the motor to 7000 rpm on every pass. No problems. A steel sleeved intermediate shaft is a very good idea.

While on the subject of oil pumps, install a surge baffle between the pump and the rear main. It will help keep oil from getting into the crank on acceleration. I also suggest, using it as a pattern and port matching the rear main inlet and pump outlet to it. In addition, enlarging the oil pocket and radiusing the oil port in the rear main will let the oil flow easier and help keep it cooler. To help increase the efficiency of the pump, pull the cover and check the clearance between the gears and the cover. Flat sand the case until you have .002". While the pump is apart, use some cartridge rolls and smooth out the discharge port. It is a rough casting and smoothing it will ease the load on the pump. You could radius the the hole while there. These easy to do things will help the oiling system quite a bit.

Gene,??
I honestly don't think side clearance from .015 to .030 is worth worrying about.
I do prefer .010-.015 for steel & .020-.025 for aluminium but I really don't get to excited about it unless it gets too tight.
Hell, half the stock GM engines running around out there have more side clearance than you do smile.gif



RB69,
The 1094's are not a "weak point". I have run them on 13.0 aluminium head super late model type engines with no problems.

Bob,
Squaring the decks is always a good & idea as long as you are doing it you might as well get it set where you want it.
And as Pat said, make sure it is referenced off the mains or find another shop regardless of what they tell you about what the "factory does", that's what you are trying to correct ;)
If you want a small bore .039 gasket use the FelPro 1043. it is 4.080 x .039

BB427,
"Mike, my machinist and I decided to get the side clearances down to .015 ( and he could since he remachined the crank and rods, or so he says)"

I dont know of any way to reduce side clearance once you have too much, unless you are going to weld up all the crank throws and regrind the sides. Or weld up the sides of the rods and remachine them.

Did your machienst do any thing on the thrust fillet on your crank?

If you decide to go with the stock pump and Z-28 spring, the part # is 3848911 available at any Chevrolet dealer.

Mike

13.0 aluminium head super late model type engines OK as far as it goes, but.... How many miles? How many heat/cool cycles? How many zero-degree cold starts to full heat sitting in the driveway in the driveway in the morning?

Every single street-driven motor I have ever torn down that had steel-shim gaskets in it - every single one, with not even one exception, including both factory-installed and rebuilds - had evidence of fire leakage, usually between the center 2 cylinders where the head gets hottest. Now granted I haven't torn down a whole lot, maybe as many as a hundred or so, but that's not the kind of odds I'd like to work with, personally.

What works acceptably well on a race car for a few hot laps or passes down the 1320 or even a whole season doesn't necessarily translate to the street.

Well,,,
I have two I can think of right off the top that have been running for a number of years with 1094 felpros. One is in a Porsche with a 350 that the guy drives almost every day & also takes it to Nevada when they close off the roads every year for the race they have. This engine had well over 40,000 on it when I redid it. Brodix heads & no leakage.
The other is a purpose built 350 that is in a propane service truck that is 11.0 compression & has over 80,000 miles on it & has been running for over 5 years.
This thing weighs something like 12,000 lbs & is a 4wd that runs up & down some hills around here on service calls that will tax just about anything.
I have others but I can't tell you how many miles or cycles they have on them as I haven't seen them since I built them.
Again, there is nothing wrong with the FelPro shim gasket with the proper surface finish.
I will agree that they will show heat between the cylinders more so than the standard felpro but at least in the engines I have done were not leaking.

And just for info, one of these circle track engine has two seasons on it & trust me when I say they go through some heat cycles that would scare you in normal operation & typically see about 7500 on a regular basis quite a few times durin a race ;)

Chevy small block? Gasoline? Ordinary daily driver?

7500 RPM down the straights with no thermostat (or a marine one) and a Stewart water pump and C&R radiator is not a heat cycle. Crank the car up at 7am when it's -15 outside, go back in and brew a pot of coffee, the phone rings, 30 minutes later you remember that your car is now sitting there in fast idle and has been for the last half hour, at 2000 RPMs, you drive it to work and park it and come back out at 6pm and -15 again ..... that's a heat cycle.

Motors I've built for round-track racing with steel-shim head gaskets worked fine. I'm not talking about that, and neither is the person asking the question. He's asking about a street driven, moderate compression, gasoline-fueled, daily driver with probably a more or less stock cooling system, that he probably wants to last for decades and/or hundreds of thousands of miles in spite of occasional burst radiator hoses while his daughter is driving it to college and all those other lovely things that the real world seems to dish out to us on the street. Steel shim head gaskets are guaranteed to fail sooner rather than later in that type of application. High-quality composition gaskets such as FelPro or Victor-Reinz, in an adequate thickness such that their thickness swamps the dimensional changes in the castings, stand a much better chance of long-term survival.

I will certainly not build one for myself with steel-shim gaskets, nor recommend that someone else do so in their street motor. Racing.... maybe, given the right conditions. Street.... never. We've learned a thing or 2 since the 60s.

Ok,, you are right, I am wrong, Brodix is wrong, a service truck with 80,000+ miles does not constitute what you consider good service life,& a Porsche with a 350 engine in the back & the radiator in the front with 40,000+ miles on it isn't considered marginal cooling & a 1094 felpro with it's well engineered coating will never live on the street. :(

Bob,
Sorry about wandering off with your post, I hope all your questions were answered ;)

I haven't had any problems with the melling high volume pump in the last three engines I assembled. I do pay close attention to oil drainback and usually radius the return holes and also drill a 1/2" hole in the block on the left side rear pan rail for added drainback behind the rear crank counterweight. The last engine I built I pipe plugged the holes in lifter valey above the cam and drilled them out to 1/8" in an effort to reduce windage and route most of the oil to the rear. I always chamfer the oil passage in the rear main cap at the pump attachment.
Pat Kelly what psi is the stock replacement melling putting out at 7000 rpms and at idle? If I we run the stock G.M. pump or stock replacement Melling will it provide 10psi per 1000rpms? I see it was mentioned to use a Mr. Gasket spring. This engine will be hammered occasionally, shifting at 7000, I just can't see a stock pump providing 70psi and adequate volume but I'm probably wrong. I haven't seen any spark scatter problems with the High volume or distributor gear wear either.

Wolfplace, Thanks for the help on this, I wouldn't have any problems running a shim gasket if the deck was in better shape, but if I'm getting it cut I might as well go to zero and get the thicker gaskets.

I also apologize for arguing; I don't want to get caught up in some kind of argument that digresses from the issue at hand. I just hate to see people make the same mistakes that people (myself included!) have been making time and again, year after year, and always getting the same unhappy results. That's the very definition of insanity according to some.... doing the same thing, but expecting different results. I'd rather see people have successful experiences at this hobby without having to learn their lessons the hard way like I did.

In light of all that, I'd strongly urge you to zero-deck the block for optimum compression, especially if you're already having to pay for getting it decked anyway just so it won't be defective; and use composition head gaskets.

No problems with the arguing here, I appreciate everybody's input. We all learn when information is shared.
I have done body work professionally for 20years so I try and help out on the body shop side of this site. And I look for help with the mechanicals here. This forum is the best. graemlins/beers.gif

69,
And on that you will get absolutely no arguement from over here, I agree completly it is the best way for Bob to go. :D


Bob,
It's really not a drainback issue. The pump will only flow as much as your clearances will allow. If you install a larger pump it will just bypass more oil internally at the relief.
If you want more pressure with a stock pump you will need to change the spring as most will go into bypass at less than 50lbs. The max oil pressure you are seeing is when the relief valve opens in the pump.
I use hi volume pumps in a lot of engines because the customer feels better about it after reading all the propaganda.
I personally feel you will not hurt a thing running the hi volume pump but in almost all cases I also feel it isn't necessary.
Also 60lbs of pressure hot is just fine for most applications, we set most of the dry sump pumps between 60 & 70lbs hot on almost all the ones we do & I have one 332 that sees about 8600 & another 311 that sees about 9500 pretty regularly & both seem quite happy with 70lbs.
BTW, the mains & rods are under .002" on this engine.
On another note, I don't persoally like to plug or restrict the holes over the cam on a flat tappet street engine.

I used to promote high volume pumps and agree they have their place. However, after my last engine build I'll no longer just put them in everything.

I paid real close attention to bearing clearances on my 383. I ended up with 0.0022" rods and 0.0025" mains, except for #5 which was at 0.003".

I ran the Melling HV pump with the stock 40 psi spring. I did a bunch of measuring and verified that the bypass port in the pump just begins to uncover at about 38 psi.

With hot 30 wt oil (and I mean hot - 200°F coolant temp on a 100° day and some in-town idling) It makes 30 psi at 600 rpm idle in gear, and 38 psi at 750-800 rpm in neutral. It makes 40 psi to about 2,000 rpm and then begins to climb, overwhelming the bypass. By 3,500 rpm it makes 60 psi and keeps going up from there.

Upwards to 4,500 rpm under hard acceleration the pressure starts to fluctuate, and I've nailed that down to some baffling issues with my custom fabbed oil pan/windage tray combination which I am straightening out this month. At the same time, I will be installing a stock Melling pump I have laying around, along with a 50 psi spring.

I figure all I'll give up is about 10 psi at idle, and this pump/spring combo should still easily make 55-60 psi hot at 6,000 rpm.

You appear to be paying close attention to clearances with your combo. I encourage you not to run the high volume pump.

Bob, I'm not real sure what the pressure is at 7000 since I'm in the middle of a race. Cold idle is 65-70, warm idle is 40-45 in gear, neutral idle is 55-60. The pressure comes right up at more than 10/1000. Since this is a strip car, the oil never gets real hot. Water temp at launch is 160 and about 180 when back at the pits. When I cold start, I warm the engine to about 180 then cool it down. No oil temp gauge, so I check that the oil is warm by putting the car in gear and checking that the oil pressure is about 40 psi.

BTW, Chevy used shim head gasket for many, many years before the composites came out. I have almost 100,000 mostly in town miles on a set in my driver (Fel-Pros at $6.50 each, original deck not surfaced). I'm using shims in the bracket car, too (Victors at $14 each, they were the thickness I needed or I would have used the cheapies). Neither have been re-torqued (there is a trick for this). Decking and truing is an excellent idea, though.

Alright, you guys talked me into it. We'll be using the stock replacement Melling pump. It will be fired on a test stand so spring selection won't be a big deal if we have to change it. Thanks for all the input. Bob

Dalton's Ride (http://community.webshots.com/album/117226417GuAuSn)

The Z28 spring gives about 50 psi hot cruising and the Mr G spring gives about 55, with a correct modern street motor oil such as synthetic 10W-30. Either is a good choice for a street motor and fits right into the M55 pump, and produces the same thing (or slightly better with the MR G spring) as a "Z28" or "Corvette" pump, for less money than buying it that way (M-55A for example).