The 360 build that has more turns than Willow Springs

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1WildRT said:
So it was built in 2012-13... How long did it run before it lost the head gasket? Sounds like the heads didn't get torqued properly or those bolts caused issues... One thing when you run ARP or any other premium bolt, they have a higher torque spec, if you use the stock torque spec you never actually properly stretch the fasteners which can lead to a premature failure...

But like I mentioned earlier, pretty common problem on smallblocks...

Blown Head Gasket
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I think it was about 5 years ago that Mike parked the car in disgust. He told me a few times that he got tired of the high performance stuff so he just stepped it down to a stock 360 for the sake of low maintenance. It sat for about a year but around 2021 he and his dad put in the stock engine to get it up and mobile again.
It is quite possible that the heads were not torqued correctly. The different torque spec is an interesting point and it could be the reason for the failure.
I'll add that the gaskets that blew are the cheapest ones that Fel Pro makes....the 8553. They are $20 each at Summit.
 
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The pistons and Total Seal rings arrived today.

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The space between the top ring and second ring is pretty big compared to the Speed Pro pistons:

Piston 1.JPG


I don't recall the ring gaps being so big!
I'll have to look at my tech sheet for the Icon pistons I put in the 440/495 but I thought there was a .004 X bore size guideline. Check this out...


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I ran under 0.020 ring gaps on the top rings in the 440 but using this new formula, this smaller bore 360 needs to be .026 top ring gap, .016 for the second ring? Really?
 
Hypereutectic... Use the big ring gap.. Or wish you had... That larger distance between the top & second ring plus the reduced diameter in that location traps heat in the top ring... Run the gap to tight & the ring ends butt... Ring ends butt & bad stuff happens.... You don't want any detonation with Hypereutectics either... They don't respond well to it...
 
I've been reading that a ring gap a bit wider than ideal is FAR better than one too tight.
These are only my second set of the Hypereutectic pistons. The other builds are either forged or cast. The car that THIS engine is going into has a stock bore, cast piston 360 with #308 heads. I bought the short block from the SAME guy that had THIS 360. He spends money, screws stuff up and then I swoop in to get it at a great price!
This roller 360 came with a Hughes roller cam, 1.6 Hughes rocker arms and shafts, an Edelbrock Air Gap intake and a Holley 750 for $500.Can you beat that? The Intake alone is around $450 new. The cam is over $500 new, the carburetor is $600, the rocker arms are over $1000....
 
This is the tech sheet that came with the Total Seal rings I put in the 440/495 with Icon forged pistons:

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Those ring gap recommendations are not intended for Hypereutectic pistons... Ignore them...
 
I file only one end of the ring and I file like I'm filing DOWN into the cylinder if the filer was on the deck.
 
It's a known weakness, generally below 11-1 good machining, good gaskets & hardware your fine... But push it up to 12-1 or miss any details and the odds stack up pretty quickly... That one extra bolt seems unnecessary but it adds a lot of clamping load..
 
Kern Dog said:
I have never had a head gasket failure in anything. I've had oil leaks, vacuum leaks and water leaks at water pumps but my luck with head gaskets is good.
I'm not one to claim that I've built hundreds of engines but I've built a few Chevy 350s, a 400, a few 440s, a 383, three or four 360s and done numerous engine swaps.

I'm thinking of adding this to the build:

Cloyes Gear 9-5387 Cloyes Replacement Timing Chain Tensioners | Summit Racing

The intake is heavily stained so I will paint it either dull aluminum or the same orange the engine will be.
The car it was in had an electric fuel pump so this engine had no fuel pump eccentric on it. I lost the Woodruff key in the end of the cam so I'll need to source that. I did take pictures of the other 360/5.9 that is getting rebuilt here at the same time...

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Yeah, that is right.....Rich and I are building similar engines at the same time in the same shop out back....

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Click to expand...

I wouldn't get the tensioner, but get a good quality true roller double roller...

My chain of choice is the edelbrock true roller double roller, I've been using them for decades and they hold up well in daily drivers... I've put over 125 k miles on them and they haven't stretched much...

Edelbrock Performer-Link True Roller Timing Chain Set
 
In an instance of irony, I stumble across THIS video...



They picked up this used engine that had a roller cam, Air Gap intake, Edelbrock heads and roller rockers for a similar build as I'm doing here...
 
Kern Dog said:
In an instance of irony, I stumble across THIS video...



They picked up this used engine that had a roller cam, Air Gap intake, Edelbrock heads and roller rockers for a similar build as I'm doing here...
Click to expand...

I'm a subscriber to PN. They're not Mopar only, but they have done several nice Mopar builds over the years. With a decent cam and aluminum heads, these engines can make 400+ hp and torque all day.
 
I talked with my machinist yesterday. The block needs final honing, the decks were clean but will get a cleanup surfacing.
Maybe the cause of the gasket failure... the heads did need to be resurfaced .009 each side. There was some rust from water sitting in a couple cylinders along with very slight raised areas (bulges ?) on the gasket sealing surface. The surfacing may bump compression slightly. I CC'd another '308 head last week and it came in at 72 ccs. My 9.3 to 9.6 compression ratio numbers are based on a 72 cc head, 5 cc valve reliefs, pistons between zero deck and .012 in the hole, and .050 head gasket. If the chambers are 70 ccs, that changes to being between 9.5 to 9.8 to 1.
If need be, I could step it up to Cometic head gaskets in a thicker version.

Summit Racing has a discount code that expires tonight...$20 off of $250 and more savings from there.
Good timing too. I'm ready to order rod and main bearings, cam bearings, core and frost plugs as well as the timing chain tensioner. The timing chain that was on this engine was still good so I'll reuse that. It is a double roller but only has one woodruff key groove unlike the more fancy ones with multiple keyways.
Hey...This isn't meant to be a full tilt race mill, I just wanted to build something a bit wilder than the low compression 360 in the car now.
 
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I love when parts come in.
Main bearings, rod bearings both .010 under.

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I’ll see my machinist Thursday to hand off the cam bearings and the distributor drive bushing.

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I didn’t need the fancy brass core plugs. These will be fine.

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I do like this though.

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One piece cam plate, oil drip tab and chain tensioner.

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To restate, my machinist is semi retired. He lost contact with his various vendors and suppliers so I just get the labor done by him. That is fine since some guys will mark up the parts they get to use on your engine.
I was happy that the heads had no cracks!
 
I took the cam bearings in to the man.
He is almost finished with the heads too, they just need valve stem seals.
Does anyone know the part number for the stock PC style seals? Not the umbrella type.
 
It has been many years since I have built an LA series engine.
I've torn down several but assembly is another matter. The last few builds that I have done are big blocks. With those, every time new cam bearings are installed, I've had to run this through to clearance the bearings:

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It has diagonal grooves in the journals packed with bearing grease.

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After this "clearancing tool" makes several passes, the good cam is able to spin in the block. Before, it cannot. MY machinist said that this is common with the big block Mopars. Is this a known issue with the LA and Magnum blocks too?
If so, I'd need to pull a cam from a spare engine and modify it for this.
 
Kern Dog said:
It has been many years since I have built an LA series engine.
I've torn down several but assembly is another matter. The last few builds that I have done are big blocks. With those, every time new cam bearings are installed, I've had to run this through to clearance the bearings:

View attachment 1716369727

It has diagonal grooves in the journals packed with bearing grease.

View attachment 1716369729

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View attachment 1716369728

After this "clearancing tool" makes several passes, the good cam is able to spin in the block. Before, it cannot. MY machinist said that this is common with the big block Mopars. Is this a known issue with the LA and Magnum blocks too?
If so, I'd need to pull a cam from a spare engine and modify it for this.
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The guy doing my block had mentioned that all Chrysler engines need this treatment - even LAs. Apparently Chrysler cam bores weren't the best. Do you have a spare cam? I was thinking about making one of those myself. I think I've got a spare floating around somewhere.
 
Kern Dog said:
It has been many years since I have built an LA series engine.
I've torn down several but assembly is another matter. The last few builds that I have done are big blocks. With those, every time new cam bearings are installed, I've had to run this through to clearance the bearings:

View attachment 1716369727

It has diagonal grooves in the journals packed with bearing grease.

View attachment 1716369729

View attachment 1716369730


View attachment 1716369728

After this "clearancing tool" makes several passes, the good cam is able to spin in the block. Before, it cannot. MY machinist said that this is common with the big block Mopars. Is this a known issue with the LA and Magnum blocks too?
If so, I'd need to pull a cam from a spare engine and modify it for this.
Click to expand...
That IS a common issue with BBMs and I have found the bores in the cam tunnel to be undersized on occasion
 
mopowers said:
The guy doing my block had mentioned that all Chrysler engines need this treatment - even LAs. Apparently Chrysler cam bores weren't the best. Do you have a spare cam? I was thinking about making one of those myself. I think I've got a spare floating around somewhere.
Click to expand...
I haven't had a small block with that problem in 20+ years. Only big blocks. If a shop pounds the bearings in with a expandable mandrel and a hammer, THATS what causes it often times. The use of a hydraulic cam bearing tool eliminates most of those problems.
 
NC Engine Builder said:
I haven't had a small block with that problem in 20+ years. Only big blocks. If a shop pounds the bearings in with a expandable mandrel and a hammer, THATS what causes it often times. The use of a hydraulic cam bearing tool eliminates most of those problems.
Click to expand...
That's great to know. Thank you! Does the mandrel-type bearing install tool distort the bearings or something?
 
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