How to assemble a shortblock

[Dave]

Absolutely lube the studs and bolts, all of them. Any kind of lube is better than just dry, plain ole engine oil will even do wonders.

Can't stess that enough! Torquing dry can give you up to a 20% low reading on a torque wrench. Moly lube is the best, but like said even 30 wt does wonders. For some reason at work, I ended up being the go to guy for fastener questions. If you have metric taps, you're sure ahead of me! Good luck, you got more guts in doing that mod motor than I have or will have.
Dave - snow free for 10 days now

[Warpig Racing]

Just another reminder. Be sure and use anti sieze compund on bolts that go into alum (esp heads).

Not sure on how this motor is designed.. but silcol sealanat the rear main cap as well.

Locktight might be useful on critical internal bolts (oil pump, cam gears, etc).

[MalcolmV8]

Great. Thanks for all the tips so far.

First issue. I'm reading over the specs for my rings to see where to file them (ring filer arrived today) and step 1 that came with the rings says to install the torque plates to the motor before checking clearance of the rings in the bores. Well shoot I don't have a set of torque plates. Is this really 100% required?

I know the machine shop told me if I go and double check their work I'll see my bores are not 100% round but maybe slightly oval and that's not because they screwed up but because you have to measure the bores with torque plates installed which simulate the heads been bolted up. Which is also how they bored and honed it. That makes me think there's some merit to what the instructions that came with the rings say.

What do you guys think?

[cgrey8]

I would tend to agree. The ring gap spec would be specific to a reading taken with a torque plate.

However I'd also think that there is a procedure for setting ring gap without a torque plate that requires you have the ring's gap oriented in a certain direction and at a certain location in the bore to measure the gap. Assuming the machining was done correctly, a procedure like that should be readily repeatable and accurate. Now finding that procedure and new ring spec might be difficult and I would expect the non-torque plate spec & procedure to be different depending on whether you have a cast iron or aluminum block.

[usmcrp1044]

Install one of the heads and then put the rings in from the bottom.
Theres your torque plate.


Thats just a guess if that works by the way...

[MalcolmV8]

Install one of the heads and then put the rings in from the bottom.
Theres your torque plate.

You know I was thinking of doing that LOL

I called the machine shop and he rattled off all kinds of numbers but basically what it came to is this.
He said the torque plate actually opens up the very top of the cylinder bore making it slightly larger. On a cast iron block though he said it's very minimal and the correct way to gap my rings is one inch down from the top instead of at the very top. He said if I had an aluminum block it would be a lot more critical because they distort more.

You can tell my motor was still fresh in his mind because it just pops out his mouth that my bore is 3.5725 and my rings call for bore x 0.0055 so I should have 19 and a half thousands ring gap. He said as much boost as I'm running now and how much I intend on running in the future when I get my kenne bell he said go for 20 thousands.

[Warpig Racing]

Yes.. you should measure further down the cyclinder. From what I have always done is to check it 3 places in the cyclinder. I would think the further down you do the less not have a torque plate on matters as it would have less distrotion at the bottom than the top. Id say if it good at the middle and bottom it should be good at the top.

[MalcolmV8]

Found a guy on the Cobra forums who offered to loan me his torque plates. I think he has a shop and he says to always use them. However shipping on torque plates is not cheap and he wants an $800 deposit (full purchase price of plates) for his security that I will send them back to him. Humm some say you must use them others say you can gap rings without them... what to do... what to do...

[cgrey8]

If you have plates, always use them. But if you don't have them, I would tend to agree that there are alternatives. And the claim that the cylinder walls don't deflect as much at the bottom of the bore as much as the top seems to have merit. It makes sense to me anyway. If I were in your position, I'd use the engine's heads as torque plates and gap the plugs in the bottom of the bores. But that's based on ZERO knowledge of that engine. But again, that technique seems logical mechanically particularly given you have a cast block.

[Warpig Racing]

What guarantees that he will refund your $800? I would hate to buy a set of those things for $800 a one time use.

Why not make a set of your own? Get some scrap plate, use your heads as template for the bolt holes, torch out the plates for the piston holes...

What about this idea... place the rings in the cyclinder... smoosh playdoh in the gaps... torque heads w/o using gasket or using your old gasket... remove heads. carefully remove the rings and measure the thickness of the playdoh using calipers or feeler guages.

youll prolly need the playdoh to check you pistion to valve clearances anyways... plus its ony $2.

I still think it is unnecessary if the gap is correct at the bottom of the cyclinders.

[MalcolmV8]

What guarantees that he will refund your $800?

Not only that but what guarantees that he'd even ship me the plates after I paypal him some $850 +- which should cover shipping too. To risky. I have to agree with you guys that just sliding the ring further down the bore should be good enough. I'll try do some testing and check ring gap at various depths in the bore. If it's different at the very top but the same rest of the way down then I know the bottom and middle is good for gaping them.

My hesitation in bolting up the heads is that I don't want to bolt them up and remove them any more than I have to and risk putting any warpage in them. I know aluminum (or any cast actually) should only warp from heat and usage but I just don't want to risk it on this boost motor. Nothing worse than blowing a head gasket on this motor since pulling the heads basically means pulling the motor.

[Warpig Racing]

Not to mention the additional stress on the head bolts/studs.

[Warpig Racing]

how to assemble a short block?

Dont forget the beer! thats the MOST IMPORTANT!

[MalcolmV8]

LOL that and my punching bag which I have a feeling I'll be making good use of. I actually had a few minutes this afternoon. I got the crank out of the packing and wiped it down and used compressed air to blow out the drilled holes from balancing as I could still see some fine metal dust in there.

I laid the crank down in the block on the main bearings. All dry and very carefully so I could double check clearance with plastigauge. However four of the main studs are extra long because of the windage tray and I don't have a deep well socket in 12 point to get to them. Time to go buy a socket.

[MalcolmV8]

OK I decided to dive into the rings. I started with cylinder number 5 which is on the end of the block and probably one of the most affected by a torque plate. I took a top groove ring and placed it as squarely as possible at the top. Oh I wiped down the cylinder wall really thoroughly first with some cleaner/degreaser sprayed on a shop towel. When done I wiped it down with miracle oil on a shop towel.
Anyways at the very top of the cylinder the 0.014 feeler gauge fit in snugish to good and the 0.015 would slide about 3/4 of the way in the ring gap but not all the way in. I then used a piston upside down to press the ring down and checked it about 1" down and about 4 more times on the way down till I got to the very bottom of the cylinder. I had the exact same results. I did not measure any difference from the top to the bottom or anything in between.

Does that mean I'm just not been accurate enough or should I be able to gap these rings without torque plates?