LA 318 advice

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Newbomb Turk said:
Here’s one for you. I had to mill close to .100 or a bit over that to get my pistons .048 out of the hole.
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That's for a needed reason, not just cause you don't want to run proper pistons.
Newbomb Turk said:
The brand new Weiand tunnel ram I have fits perfectly with zero milling. I’d have been stacking gaskets if I didn’t need to mill the block that much.
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This is a general build, say the dude ends up wanting to try a few different intakes now he's got to mill each one and are pretty much useless to anyone to use after.

I’m Just saying it might limit any future upgrade, now if there's zero chance for any possible upgrades then fine mill the **** out of it. But you might think there's gonna be zero chance then life happens now where trying to figure how to use this short block in a new project.
Newbomb Turk said:
I run my cam on a 105 ICL and LSA and I have more than enough p/v clearance.
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With no valve relief's ?
Newbomb Turk said:
Again, you don’t know what you don’t know.
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Yes I'm not an engine builder, everything I've done been to a stock short blocks.
 
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The UEM piston catalog shows 318 blocks as having a 9.578” deck height in all listings for a 318.
That’s .021” shorter than they show for an LA 360.

They have a low buck 1.741” flat top piston available.

If I were intent on decking the block, I’d take it down to .030 below that 9.578” spec……… 9.548”.
That should put these pistons down the hole about .030”.

Silvolite 3247.03 Silv-O-Lite Cast Pistons | Summit Racing
 
PRH said:
The UEM piston catalog shows 318 blocks as having a 9.578” deck height in all listings for a 318.
That’s .021” shorter than they show for an LA 360.

They have a low buck 1.741” flat top piston available.

If I were intent on decking the block, I’d take it down to .030 below that 9.578” spec……… 9.548”.
That should put these pistons down the hole about .030”.

Silvolite 3247.03 Silv-O-Lite Cast Pistons | Summit Racing
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From what experience I have with the sbm and the reading that I've and people who I have talked to, all factory sbm's have a block deck height of 9.600". They might have mentioned that having the block decked 0.022" would help with the compression ratio
 
i love how everybody is just losing their gawd-danged minds over this.

funny watching smart people get stupid because they only are able to view the exercise through their lens and not take into consideration other viewpoints.

without knowing the cam this entire endeavor is a just an active performance of mental masturbation.
 
junkyardhero said:
i love how everybody is just losing their gawd-danged minds over this.

funny watching smart people get stupid because they only are able to view the exercise through their lens and not take into consideration other viewpoints.

without knowing the cam this entire endeavor is a just an active performance of mental masturbation.
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What is the block deck height for a 318? I've always read and been told that it's 9.600"
 
Dan the man said:
What is the block deck height for a 318? I've always read and been told that it's 9.600"
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9.59~9.6 nominal is what the mopar book reads. however there are production tolerances that lead to variance.

such as i've seen rollers at 9.57

somebody that works with these as a machinist or engine builder regularly would have more granular detail than i would. i just screw **** together and hope it works.
 
Whatever the actual deck height dimension is for the block being used doesn’t really matter…………. As I said, if I was going to the trouble of decking it to use with cheaper/lower ch pistons…….. I’d deck it enough to get real close to having the deck clearance be about .030 down the hole.
Whether that means cutting it .030, or .050, or whatever.

However, I wouldn’t do any of that if the target for the end result is under 300hp.
That would get what I said earlier……….re-ring, go thru heads, done.
 
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Question for George Jets…….
Do you have a factory original piston from like a 69 318 that’s not in an engine you could measure the compression height on?
Or, know what that dimension is?

Often, the aftermarket “stock replacement” pistons have a different height than the originals.
 
273 said:
That's for a needed reason, not just cause you don't want to run proper pistons.

This is a general build, say the dude ends up wanting to try a few different intakes now he's got to mill each one and are pretty much useless to anyone to use after.

I’m Just saying it might limit any future upgrade, now if there's zero chance for any possible upgrades then fine mill the **** out of it. But you might think there's gonna be zero chance then life happens now where trying to figure how to use this short block in a new project.

With no valve relief's ?

Yes I'm not an engine builder, everything I've done been to a stock short blocks.
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WTF are you talking about? What is a “proper” piston?

You can stack gaskets if you change blocks. This **** isn’t as hard as you want it to be.

It doesn’t limit anything unless you limit it.

How many times have you checked p/v clearance with an off the shelf piston?

Do you know how much that clearance you actually need and why more clearance is bad? And why?

It’s for the same reason you see some unlimited class stuff with very wide LSA’s. They don’t do that because the wide LSA makes more power because it doesn’t.
 
Newbomb Turk said:
WTF are you talking about? What is a “proper” piston?

You can stack gaskets if you change blocks. This **** isn’t as hard as you want it to be.

It doesn’t limit anything unless you limit it.

How many times have you checked p/v clearance with an off the shelf piston?

Do you know how much that clearance you actually need and why more clearance is bad? And why?

It’s for the same reason you see some unlimited class stuff with very wide LSA’s. They don’t do that because the wide LSA makes more power because it doesn’t.
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Whatever, I see you just want to argue over nothing
 
PRH said:
….
Do you have a factory original piston from like a 69 318 that’s not in an engine you could measure the compression height on?
Or, know what that dimension is?...
Click to expand...

I think I have that dimension. I'll look and post tomorrow.

As for the rest of this thread, Wow!
 
“If” the OP’s block is in the 9.599” range, to have the pistons down the hole .100-ish, they’d have to have a CH in the 1.720” range.

When he pulls one out, there should be a way to ID what they are.
 
I'll just run in and screw everything up by telling dude to just get his rod journals offset ground, add a little stroke and move the pistons up as a added benefit
 
NC Engine Builder said:
I'll just run in and screw everything up by telling dude to just get his rod journals offset ground, add a little stroke and move the pistons up as a added benefit
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pfft! let's just take it out a little more and we can squeeze some chevy 305 pistons in there! now we got choices!
 
Newbomb Turk said:
I’m not arguing. I’m explaining why I said what I did. You just don’t like the answer.
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I never questioned what you said.

OP asked how should he get more cr and he gave a few options, mainly..

A. KB pistons

Or

B. Heavy milling

And I said I prefer A. especially if there's a possibility of upgrades down the road, if there's zero chance of upgrades I could see going B.

Apparently to you, only an idiot would give that answer.

Then you seemed to take offence that I said proper pistons instead of aftermarket and that I said the KB's would have more piston to valve clearance, apparently I'm wrong and zero decked stock pistons obviously have more p/v clearance lol.
 
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junkyardhero said:
i love how everybody is just losing their gawd-danged minds over this.

funny watching smart people get stupid because they only are able to view the exercise through their lens and not take into consideration other viewpoints.

without knowing the cam this entire endeavor is a just an active performance of mental masturbation.
Click to expand...
No wonder I feel so sexy.
 
NC Engine Builder said:
I'll just run in and screw everything up by telling dude to just get his rod journals offset ground, add a little stroke and move the pistons up as a added benefit
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Mega old school style. It works. I kinda like it. lol
 
Or put a 360 crank in it, and mill some off the pistons.
 
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