Mixing bearings for clearance

[Rich Biebel]

Stock pistons often have an offset but the rods themselves are not offset. The offset is about .060" on a small block......Maybe that is what you meant and I misunderstood the question......In Stock we often used TRW pistons and turned them around so the offset went the other way...... The TRW forged pistons that were used to build a 350 Stocker engine has the offset in the pin hole......L-2256.....forged flatop 4 valve relief......Hang them on the rods so the arrow that is normally facing forward is toward the rear......

I had a G-H/SA '69 Nova back in the '90's and built a "cheap" shortblock using those pistons.........Dykes rings with spacers......

[Chris "drooze" Wertman]

[QUOTE=Rich Biebel;176267]Maybe that is what you meant and I misunderstood the question......QUOTE]

It was, the answer was worded wrong, I have my kids over and I miswrote what I meant being shot at with a large plastic man from a cannon as well as dressin barbie dolls in between. Its like herding cats right now.


That was it.....I miswrote what I mean ,I used the phrase perpindicular to the center , and that was not even close to what I meant...

Wonder if there is a Leauge for herding cats ? Id be ace...

[Alan Roehrich]

Buy your self a good bolt stretch gauge and use it religiously, forget using a torque wrench on rod bolts. And use it when you check the big end of the round for straightness and roundness. You are doing that, aren't you? Use the bolt stretch gauge when you check the ID of the bearing in the rod, too.

The old rule of thumb "0.001" of clearance for every 1" of journal diameter" will do you just fine until you figure out the real needs of the engine. It holds true in most engines, especially when the rod journals are between 2.0" and 2.3", and when the main journals are between 2.3" and 2.75". This is if you are using any good race oil between 5W/20 and 15W/40. If you run 20W/50 (why?) go a little looser, if you run 0W/10, tighten it up some.

A properly plumbed accumulator will not cause a problem, an improperly plumbed accumulator will blow your engine.

I like coated bearings, I have mine done at HM Elliott. We could do our own, but considering the time and operation involved, we don't. Honestly, they sell me the bearings already coated cheaper than I can buy them and coat them myself, if I consider time, materials, and equipment. They now do the coating for Mahle Clevite. They coat my skirts, if I don't have it done when I buy the pistons.

Avoid the rest of the trick stuff. If it won't live at all without cryo and DLC, it won't live anyway. Yes, you can do that stuff later and maybe find some gains. But right now, you need something that runs and lives. Follow the number 1 rule of engineering, because it applies to racing just as well: KISS. Keep It Simple, Stupid. A wise old racer named Tom Polk once told me "Tricks are for kids, you pour 'em in a bowl, pour milk on 'em, and eat 'em". Some of the best advice I've ever gotten in well over 30 years of this stuff.

You need good solid machine work, and good solid basic parts. All of the other silly stuff will do nothing but cause you problems, at least until you have 3-4 good solid engines you've done that run well and last. After that, then you go fooling with the rest of it.

By the way, you've already met a real good guy to help you through all of this, Bill Grubbs. Talk to him, listen to him, and pay attention. He knows a lot more than he lets on, and he'll show you the ropes. He's no engine builder, and he'll tell you that. But he knows who IS an engine builder, and where to get good advice and information.

[Chris "drooze" Wertman]

Buy your self a good bolt stretch gauge and use it religiously, forget using a torque wrench on rod bolts. And use it when you check the big end of the round for straightness and roundness. You are doing that, aren't you?

Checking stretch, yeah normally, on these last 2 bottom ends no, we didnt put em together and well, yes we will.

The old rule of thumb "0.001" of clearance for every 1" of journal diameter" will do you just fine until you figure out the real needs of the engine. It holds true in most engines, especially when the rod journals are between 2.0" and 2.3", and when the main journals are between 2.3" and 2.75". This is if you are using any good race oil between 5W/20 and 15W/40. If you run 20W/50 (why?) go a little looser, if you run 0W/10, tighten it up some.

Thanks, that makes sense, I am going with 5/20 for now, our other engines lived with it just great.

A properly plumbed accumulator will not cause a problem, an improperly plumbed accumulator will blow your engine.

Its plumbed right, pretty hard to plumb it wrong on this engine It is/was working properly I put an inline shutoff valve so I can shut it full, manunally to pull a full accumulator should I want to, shut off kill engine, drain, precharge right, proper quantity in accumulator, set to 20 psi drainback....I dont like the solenoid valve it had but Ive seen the same exact valve failt in Gas and Steam applications. (it a personal thing


Avoid the rest of the trick stuff. If it won't live at all without cryo and DLC, it won't live anyway. Yes, you can do that stuff later and maybe find some gains

Not looking for gains really, the issue with these engines, sort of is there are really NO other parts that are accepted other than the OE parts on many items, Rockers are powdered metal for example and prone with a score to shatter, that happens even in street engines with a high lift and ramp, the other item are the shafts, noone is making a hardened shaft for these, I am going to have some chromed perhaps, I havent decided, I want to see what the DLC does there, even with mild short run time the damm things gall horrible, on a street engine as well, they well, just suck. And on, those are the things Im trying to lenghten the life of just a bit. Turning one of these at 7k+ makes the shafts look like crap in short order , so.....it annoys me, they are way too soft, and until I can get some new ones made, or ordered that are harder, well this is the only option I have.

You need good solid machine work, and good solid basic parts. All of the other silly stuff will do nothing but cause you problems, at least until you have 3-4 good solid engines you've done that run well and last. After that, then you go fooling with the rest of it.

Turnaround time is an issue for us, my buddy well hes knee deep in Merlin V12's and a few Jumo's P&W and other warbird crap for the Air Season...Noone else (for THIS 5.7 can turn stuff around fast enough) the next 2 I should be able to find someone solid.....I hope.......

Agreed, the shafts and rockers are something we have always fought and so do other guys even in HP street apps, its life , other than a 2000$ jessel conversion, and well cant exactly run that here. The rods suck period, and Monday Im going to be back on the phone as others suggested trying to find SOMETHING that will fly and I can get approved. Eagle is as good a bet as any. But the first 5.7 will still have the Scat rods, the only other option is to sit around and hope and wait someone will offer a rod....yeah that aint happening.

By the way, you've already met a real good guy to help you through all of this, Bill Grubbs. Talk to him, listen to him, and pay attention. He knows a lot more than he lets on, and he'll show you the ropes. He's no engine builder, and he'll tell you that. But he knows who IS an engine builder, and where to get good advice and information.

Bill was very very helpful, and well, one of my biggest regrets was having to pull out and not being able to pick his brain some more I hope to see him again soon at the track. He is sharp as a tack and I know what he says is true it takes about 10 seconds to spot that.....as far as how much he knows I have no doubt it is extensive, experience breeds that.

And well, were on a Crash Course Stock Elim "experience" just hoping using the word Crash dosent come back to haunt me...lol

Alll excellent advice.

Cheers

Chris