LA 318 advice

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To me, If your gonna do it, (rebuild it) I'd build the short block right, sacrifice on other parts of the build.
You got a good short block with proper pistons can always upgrade the other parts later.
 
Newbomb Turk said:
I know this because it's in the Chrysler engine book and I've done it many times. Well, the amount to mill off isn't but the deck thicknesses are.

The OE passenger car stuff has about .500 thick decks. You can take .100 off of that. If you take more yo can compromise head gasket sealing but the Chrysler stuff can go a bit thinner than a Chevy deck because Chrysler used blind head bolt holes and the head bolt holes are supported by bracing under the deck. Bracing for lack of a better term.

The X blocks have a .750 thick deck and the R blocks are 1.00 thick.

I disagree with the argument that compression ratio changes make little difference. It might not make much difference on a dyno, but in the car it's a big difference in drivability. You don't see that on most engine dyno's. Compression ratio increases also increases expansion ratio. That's also a big deal because it affects blowdown and helps reduce pumping losses.
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Nope. Not all head bolt holes are blind. This has been hashed out here before many times. I've seen both myself. Blind holes and bolt holes open to the water jacket. Others have here as well.
 
I’d do a basic re-ring of the bottom end.
Have the heads checked out, milled .030-.040…….. make sure the springs are suitable for the intended(appropriately sized) cam, and put it back together.

When you decide you really want more power, use the $$$ you’d spend on things like pistons and decking and find a complete 360, and go thru that.
 
Well, as I mentioned it in the thread title, I came here for advice. And I feel I made the right choice is asking on this forum.
So I think I’ll digest the information, and based on the last page of replies, I’ll rethink shooting for 8.9-1 SCR and have the deck squared, and .020 off after that, will wind up around 8-1, and to be honest, the truck will scoot along just fine.
Regarding the transmission, it’s a 727, the rear gears are currently 4.11’s, I’m thinking of moving to a 3.5-ish rear gear when I come across an axle with proper WMS to WMS.

Thanks all, any more thoughts please don’t hesitate to write them down.
 
Newbomb Turk said:
I know this because it's in the Chrysler engine book and I've done it many times. Well, the amount to mill off isn't but the deck thicknesses are.

The OE passenger car stuff has about .500 thick decks. You can take .100 off of that. If you take more yo can compromise head gasket sealing but the Chrysler stuff can go a bit thinner than a Chevy deck because Chrysler used blind head bolt holes and the head bolt holes are supported by bracing under the deck. Bracing for lack of a better term.

The X blocks have a .750 thick deck and the R blocks are 1.00 thick.

I disagree with the argument that compression ratio changes make little difference. It might not make much difference on a dyno, but in the car it's a big difference in drivability. You don't see that on most engine dyno's. Compression ratio increases also increases expansion ratio. That's also a big deal because it affects blowdown and helps reduce pumping losses.
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Not everyone looks through race goggles at everything.
 
Another thing got to keep in mind is how likely will you upgrade later?
If there's like zero chance at any future upgrades, then ya could mill the **** out of it but there's a chance there's gonna future builds off the short block, I'd do the short block right.
 
RustyRatRod said:
Nope. Not all head bolt holes are blind. This has been hashed out here before many times. I've seen both myself. Blind holes and bolt holes open to the water jacket. Others have here as well.
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Everything up to the mid 1980’s has blind holes.

All 340’s and 273’s have blind head bolts.

The 1985 virgin I just took apart yesterday has blind head bolts.

I wouldn’t use a block that doesn’t have blind bolt holes.
 
RustyRatRod said:
Not everyone looks through race goggles at everything.
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WTF does getting the CR reasonable have to do with racing?

Street guys miss out on a lot because the refuse to realize simple ****.

You keep saying it doesn’t make a hp difference but it does. A water brake dyno just won’t show it.

Building anything under 9:1 today is just crazy. Even in a tow rig.

You can’t test drivability on a water brake dyno. And for the guys who love to over cam everything it’s a bonus.

Not everyone wants some 8:1 slug.
 
Newbomb Turk said:
WTF does getting the CR reasonable have to do with racing?

Street guys miss out on a lot because the refuse to realize simple ****.

You keep saying it doesn’t make a hp difference but it does. A water brake dyno just won’t show it.

Building anything under 9:1 today is just crazy. Even in a tow rig.

You can’t test drivability on a water brake dyno. And for the guys who love to over cam everything it’s a bonus.

Not everyone wants some 8:1 slug.
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No, I didn't say it doesn't make a HP difference. And I also didn't say build an 8:1 motor. Since you're cramming words in my mouth, you know where you can cram it.
 
273 said:
Another thing got to keep in mind is how likely will you upgrade later?
If there's like zero chance at any future upgrades, then ya could mill the **** out of it but there's a chance there's gonna future builds off the short block, I'd do the short block right.
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Ok, how is milling the block wrong? If you’ve never been an actual machinist and engine builder explain your answer.

Chrysler since at least the 1970’s has said to deck these blocks enough that on some of the pistons need to come out of the deck. How else do you do that? Make the piston longer? That’s dumb. It’s already too long.

I can’t understand why milling a block is the crime you all want it to be? Because an intake won’t fit?

If that’s the case you’re not an engine builder because at least 50% of the time the intake needs to be milked to fit.

Unless you are a hack and you slot the bolt holes. I don’t do **** like that.

If your only reason to not mill a block is that an intake won’t fit you need to get more experience.
 
RustyRatRod said:
No, I didn't say it doesn't make a HP difference. And I also didn't say build an 8:1 motor. Since you're cramming words in my mouth, you know where you can cram it.
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You said it doesn’t make MUCH of a difference. Is that better?

It makes a BIG difference IF you do it right.
 
Newbomb Turk said:
Ok, how is milling the block wrong? If you’ve never been an actual machinist and engine builder explain your answer.
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Well say he takes 0.100" off the deck any head upgrade down the line will need to be mill for the intake to fit, now you got an intake or head that only work's will blocks that been milled a 0.100". If you go through a bunch of upgrades could leave a lot of one off parts.
Plus your building power on stock pistons limiting future upgrade power capablies valve clearance etc..
Newbomb Turk said:
Chrysler since at least the 1970’s has said to deck these blocks enough that on some of the pistons need to come out of the deck. How else do you do that? Make the piston longer? That’s dumb. It’s already too long.

I can’t understand why milling a block is the crime you all want it to be? Because an intake won’t fit?

If that’s the case you’re not an engine builder because at least 50% of the time the intake needs to be milked to fit.

Unless you are a hack and you slot the bolt holes. I don’t do **** like that.

If your only reason to not mill a block is that an intake won’t fit you need to get more experience.
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Even so if it's just for intake, why would you rather a 0.100" milled stock piston block vs a block with decent aftermarket pistons and a cleanup mill job?
 

273 said:
Well say he takes 0.100" off the deck any head upgrade down the line will need to be mill for the intake to fit, now you got an intake or head that only work's will blocks that been milled a 0.100". If you go through a bunch of upgrades could leave a lot of one off parts.
Plus your building power on stock pistons limiting future upgrade power capablies valve clearance etc..

Even so if it's just for intake, why would you rather a 0.100" milled stock piston block vs a block with decent aftermarket pistons and a cleanup mill job?
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Because the OP doesn’t want to buy pistons.

You have no clue about pistons to valve clearance.

All the old heads who read the books have been doing it wrong for decades by milling the block.

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.

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.

I run my cam on a 105 ICL and LSA and I have more than enough p/v clearance.

Again, you don’t know what you don’t know.
 
Newbomb Turk said:
Because the OP doesn’t want to buy pistons.
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Fair enough and I understand that he's doesn't want to buy pistons, why I said if this a one time build go ahead and mill the **** out of it. But if this short block may live on in different incarnations "I" would go with proper pistons. If he don't want to under any circumstances that's fine.
Newbomb Turk said:
You have no clue about pistons to valve clearance.
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I'm sure a zero decked stock piston engine gonna have less clearance than aftermarket pistons with decent valve relief's. Is that ever gonna be a problem for the OP probably not but could be a limiting factor in a future upgrade if that's possibility.

Like this might be the only short block this guy ever builds and might need to go on through many builds ups. Or it could one of many, or something else. Most people ain't gonna build a ton of engines so I'm just suggesting to the OP you might want to build it to keep your options open.
 
RustyRatRod said:
That's it. I'm callin to talk to your wife. We gotta get your beat downs back on their regular schedule.
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I got a CPAP machine. I haven’t slept this good in years.

Now I’m full of piss and vinegar. The wife says I’m exhausting. In a bad way.

She wants me to take up swimming so I can burn off this energy. I’m thinking she is hoping I have a heart attack while swimming and then I drown.

She thinks like that.
 
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