V6 Torque Honing\Boring Plate

[87Turboid]

I use a head gasket if it's a thick composite type (after bevelling the hell out of the head bolt holes to spread the load closer to the meat of the deck). With my .027" Cometics, it doesn't matter.

I also make sure all the mains are torqued up and the motor mounts are installed (or dummies)

Thanks Earl for the info sir, would you consider making me one? Would need it soon.

 

[87Turboid]

So I guess they make two kinds with different bores, Aluminum and Cast iron depending on your head choice. Correct? So I believe I need the cast iron?

 

[BEATAV8]

BEATAV8, what is the bore on your torque plate? Shipping is cheap ground. I could put a deposit on it.

4.030”
I’m not too keen on shipping it anywhere. It’s a heavy piece, it broke the wooden box that it came in.

 

[87Turboid]

4.030”
I’m not too keen on shipping it anywhere. It’s a heavy piece, it broke the wooden box that it came in.

All good wrong bore, I was told to use a cast iron one. Cheers

 

[87Turboid]

Well just ordered the torque plate this morning, i think it will pay for itself. Cheers

 

[87Turboid]

..View attachment 323210

Hello there, so I ordered my torque plate, can you tell me what to use to for bolts for the plate? Should I use head studs instead of bolts? looks like you used both. I have Arp head bolts available. Yours was 14 bolt. Thanks

 

[87Turboid]

I would rather do nothing to a stock bore GM block, than hone without a torque plate. If any machine shop says it will be fine . . . . RUN!

I am going 15 thousand over.

 

[87Turboid]

So now I will have a torque plate available for any other members to use if wanted, just a deposit and a small charge. Cheers

 

[earlbrown]

Use whatever bolts you're going to use to build it.

 

[87Turboid]

Use whatever bolts you're going to use to build it.

Thanks Earl! So torque plate coming, JE's just shipped 3.815, TA cam bearings dual groove, Turbo crank ground 10\10. What do you suggest for main bearings and rod bearings? Any other 109 block prep?

 

[BEATAV8]

I prefer King bearings. On the cam I like the TA coated bearings.
Recommend Head studs over bolts, and use a good sealant to seal the threads. I use studs and Loctite 545 hydraulic thread sealant.

 

[87Turboid]

I prefer King bearings. On the cam I like the TA coated bearings.
Recommend Head studs over bolts, and use a good sealant to seal the threads. I use studs and Loctite 545 hydraulic thread sealant.

That’s for the info, I was thinking King and the coated TA, very good. So I have another question, what oil bearing clearance do you recommend on these engines on the mains and rods? I’ve heard many different answers and this comes down to how good is your machinist. These guys I’m working with are all racers but aren’t that familiar with this engine but I do trust them. Here is a engine builder excerpt: “ The old rule of thumb is to provide .0007? to .001? of bearing clearance for every inch of shaft diameter in a stock engine. Consequently, if the crankshaft has two-inch diameter journals, the rod and main bearings should be assembled with about .0015? to .002? of clearance.” I’ve heard these engines like some tight clearances True?

 

[BEATAV8]

I like to see .0020-.0025 on the mains, fully torqued.

 

[87Turboid]

Umh...Ok, I was under the impression these motors liked to be tight on the mains? Like .0001-.00015 Maybe I’m wrong, can you elaborate a bit on that. I can see your engine is far from stock, it’s a TA block, 14 bolt heads, is there billet in there somewhere on yours? I’m running stock 109 15 thou over, JE Pistons, crank turn under 10, stock turbo heads with comp cam and springs and lifters.

 

[BEATAV8]

I like the crank to turn easy peasy when it’s torqued up. When the clearances are below .002 it seems to get a bit sketchy on that goal. Maybe some guys like tighter clearance for the sake of oil pressure or something, I dunno. One of my 109’s has .0025-.0030 on the mains and I’m perfectly happy with that. It runs a T/A front cover with Mobil 1 0w40 and has generous oil pressure, around 25psi hot. The Buick PowerSource book has many example builds in it with their bearing clearances listed

 

[BEATAV8]

I like this article too:
http://www.enginebuildermag.com/2013/03/bearing-clearances/

 

[BEATAV8]

Here ya go.... just a few for your ref

 

[earlbrown]

I have .0009" on my mains and .0011" on the rods. I could push the crank and it would spin another round or two with just light oil on the bearings.


...here's the thing... you don't ''set'' the bearing clearances when you're building at home. They are what they are. In my case, I took my crank back to the lathe and ran the polisher so much, the journals got bigger from imparting heat. So I let it fly. I do like the idea of the radius' on the journals and the bearings being as close to each other as possible. That increases the loaded area's footprint. Same as running a taller tire for a larger contact patch.

 

[87Turboid]

Even if its only one cylinder, still used

 

[earlbrown]

POS Hardleys need all the help they can get.