The 360 build that has more turns than Willow Springs

[Kern Dog]

What did you do about the bearing clearance on the thrust main? That’s way too tight.

FYI take the advice everyone is giving you. Gap the rings wider than normal with those pistons.

When I measured for oil clearance, the Plastigage was slightly wider than the .002 marks so I wrote down .00175. It may not be quite that tight. MY 440/495 in my Charger has mains that tight. I've had the engine out 3 times and changed the bearings each time and measured the same amount each time. That engine has never had a bearing issue, I've only changed them as a precaution.
If you meant the fore/aft thrust clearance, I thought the spec was between .004 to .008. Am I wrong on that? Mine was .004 on the right side of the bearing cap but .005, maybe .0055 on the other side.

 

[TT5.9mag]

When I measured for oil clearance, the Plastigage was slightly wider than the .002 marks so I wrote down .00175. It may not be quite that tight. MY 440/495 in my Charger has mains that tight. I've had the engine out 3 times and changed the bearings each time and measured the same amount each time. That engine has never had a bearing issue, I've only changed them as a precaution.
If you meant the fore/aft thrust clearance, I thought the spec was between .004 to .008. Am I wrong on that? Mine was .004 on the right side of the bearing cap but .005, maybe .0055 on the other side.

For an automatic I’m ok with your thrust clearance. I am not ok with .00175 for mains clearance with a 2.81 journal diameter. If that were mine I’d change it right quick.

 

[Kern Dog]

The crank spins easily. A spec I read stated that the torque to rotate the bare crank is 15 lb/ft. Both of the 360 builds we are doing here turn easier than that.
I’m not calling you wrong, I just see a discrepancy.
Chiltons manual:

Main oil clearance between .0005 and .002 seems really tight!

 

[TT5.9mag]

The crank spins easily

It might now, I don’t doubt it. What’s it do when the oil is 220 degrees and the coolant temp is 190? That’s the real question. I seriously wouldn’t run it at .0017 clearance. That’s my opinion. Most stock or lightly modified engines, the minimum oil clearance is .001 per inch of journal diameter as a general rule. That puts you at .0028 minimum. Unless you are a very good machinist or a lubricants engineer and are going to run 0w-20 synthetic I’d stick to the basic guideline.

 

[Kern Dog]

You guys got me thinking so I went back....
I filed the top rings to .030. The second rings are all between .016 and .017.
The Thrust bearing main cap was pulled and I rechecked the oil clearance. I got .002. I don't know how I read it wrong before.
No offense to you, TT5.... but this engine had .010 under rod and main bearings before I tore it down. I did nothing to the crank but clean it. The only reason that I'm replacing the bearings instead of reusing them is because the prior owner blew both head gaskets and water went into the oil. The old bearings all looked fine though.
I wonder why the Chiltons book would have shown a spec of .0005 to .002 as the acceptable range. Another book I have stated that between .001 and .003 is acceptable. This engine will not be turbocharged, it won't get a blower or nitrous either.

 

[TT5.9mag]

No offense taken at all. There are engine builders that put stuff together that tight. They just plan on using a specific oil and keeping temps in check. Id hate to see you snag a bearing after putting this thing together. The big concern for me is the clearance on the other mains being different and the oil flow being different because of it.

 

[RustyRatRod]

I wonder why the Chiltons book would have shown a spec of .0005 to .002 as the acceptable range.

That's easy. Because it's wrong like a lot of other things in Chiltons books.

 

[crackedback]

Specs from back in the day when machining tolerance were about as bad as the body fit with 1/8" being OK and stacking.

Guess why they always suggested 500 easy miles.

 

[Kern Dog]

How is it that I have not had trouble before? Here is a page from the Hughes Engines site, written by DRIVEN oil:

I've driven cars with oil clearances always tighter than .003. My red car (440/495) has main bearings that are slightly different from front to rear. I'd have to look in my notes but since I first installed the 4.15 crank in 2004, they have gone from 1.75 to about upper 2s. The rods always come in around .002.
The 383 I built in 2021 was all in the .002 range for rods and mains. That one I had the crank polished since it was not scored or damaged anywhere.
I don't race these cars, I just drive them on the street and get on the throttle a bit sometimes. Maybe I never pushed them hard enough to cause a problem?

 

[TT5.9mag]

Good cooling systems, good oil, good fuel, good tune up, low load, low duty cycle, LUCK! Pick your reason why they’ve survived. It’s always hard to argue with results but I think we can all agree there are far too many variables to know all the answers.

 

[Kern Dog]

All the rings are file fitted and on the pistons. Today I was busy with other things but I did get pistons # 1 and 2 in. The oil clearance on both was .002, right where I usually see them on other builds and right in the middle of the range.
I've never measured rod side clearance in the past but I figured I'd check on this engine. With the book I have, it shows a range of .006 to .014". I was able to get a .012 feeler gauge in and no bigger.

 

[Dave999]

i don't think the Chilterns book is wrong. i think its a lift n shift direct from the factory manual...

my motor has the same mains clearance spec in the factory manual for a 265 six as the 318 because it has the same basic main journal and bearings as a 318.... i use a couple of 318 caps for more depth to the curved bit....

those two match the chilterns manual

desired .0005" to .0015"
max allowed 0.0025

spec for grocery getter.... freeway slogger, not racing.. i guess

500 mile careful break in needed

when i built mine everyone one said i needed 0.0025 2.5 inch journal and use the "racers rule"

That sounded like I was building a worn out engine from the get-go....
was conscious that i was getting advice from guys who build mopar engines for 99% track use... and i had no intention of only drag racing it

so i went with .0010 and a very careful break in, i.e full understanding of what i was about to do....

after about 600 miles 1200 Idle rpm no greater than 3000 rpm, on running in oil i dumped it stuck in some valvoline set idle rpm back to 900 and went to the track...

I have abused it each summer for a good 10 years

marginal oil pump by-design was the driver for this... Mr melling and his hi capacity pumps passed this motor by..... i wanted it to go everywhere (like the big ends) not just dribble out of the mains and lifter bores...

block was align bored due to use of the heavyweight small block caps where some lighter weight hemi 6 caps used to sit....(the whole build was a PITA this was a solution that presented itself at lower cost than getting custom caps or a new block)


Dave

 

[Kern Dog]

I admit that I am not the most experienced engine builder but I’ve put a few together that stayed together. This is a hobby for me so I have the luxury of working at my own pace. This allows me to tinker a bit then do other things that need attention.
I did not have exact numbers as to where the pistons would be at TDC. More accurately, I didn’t look as close as I could have. I looked at the published compression height and saw that it was 1.675. I read the published deck height and with what others on this forum have reported, I expected to see the pistons .015 to .020 below deck at TDC.
They are not.

Just at a glance you can see they are actually above deck.

I measured .010 to .012 using a rather crude tool.

Yeah, I had expected to use thicker than average head gaskets and it is a good thing I bought them. I have Edelbrock .051 ones here that will help. I was aiming for low to mid 9s in compression since this is an iron head build and I didn’t want to be stuck running 91 octane premium all the time. Now it looks like I’m closing in on 9.8 to 1. This is not ideal. I could run it and if it gets to the point of annoying me, I could pull the heads and install Cometics… or just order them now and avoid the aggravation.

 

[Kern Dog]

A few calculations.

Where I am now:

Does Cometic make a .060 gasket?

They did have .075 thicknesses for the 440.

The 9.29 was right in the zone of where I was aiming.

 

[Valman]

Just at a glance you can see they are actually above deck.

Above the deck isn’t necessarily a bad thing, 0.012’’ is quite a bit though. From memory, the blue Felpro head gasket is 0.054’’ compressed. I have a used one I could measure if that helps you.

You’re around 0.039’’ P/H clearance with the Eddy gasket, that seems pretty good! Is there a reason why you’re not liking the 9.8:1 SCR?

 

[NC Engine Builder]

I think you might want to measure that piston protrusion a bit closer. Visually, it looks like a lot more than .010 And it needs to be measured at the center of the piston, otherwise the piston rock makes it inaccurate

 

[Kern Dog]

Above the deck isn’t necessarily a bad thing, 0.012’’ is quite a bit though. From memory, the blue Felpro head gasket is 0.054’’ compressed. I have a used one I could measure if that helps you.

You’re around 0.039’’ P/H clearance with the Eddy gasket, that seems pretty good! Is there a reason why you’re not liking the 9.8:1 SCR?

Thanks for chiming in.
The main reason that I hesitate to embrace the higher compression is because this engine is for a car that sits awhile between drives. Out here in CA, the gas loses its punch in 2-3 months. A car that wasn’t knocking yesterday might knock in 3 months with the same gas in the tank.

I think you might want to measure that piston protrusion a bit closer. Visually, it looks like a lot more than .010 And it needs to be measured at the center of the piston, otherwise the piston rock makes it inaccurate

I agree. My method was crude and not as accurate as a deck bridge. This was just a preliminary look at it.
Thank you for that.

 

[mopowers]

That calculator isn't accounting for the gasket diameter or the volume above the top ring. Not that it would move the needle much, but maybe that'll help with your decision.

 

[Kern Dog]

I wanted to find a way to install the harmonic balancer without being a dork and hammering it on.
Yeah, I know that a tool exists to do this but I enjoy finding other ways.
Grainger had 12” all thread for nine bucks.

I cut it in half to make two of these. I just welded a 3/4” socket with 1/2” drive….

In theory, it should thread in by hand but the socket will help keep the crankshaft still while turning the nut..

There is a thick washer, a bearing and another thick washer to press against the balancer.

I had the hardware so this was an easy one. This will work on big blocks too.

 

[Kern Dog]

That calculator isn't accounting for the gasket diameter or the volume above the top ring. Not that it would move the needle much, but maybe that'll help with your decision.

True.
The top ring is WAY down compared to pistons in newer vehicles.

 

[mopowers]

True.
The top ring is WAY down compared to pistons in newer vehicles.

I'd bet the gasket diameter makes a bigger difference at the thicknesses you're looking at.

 

[mopowers]

I wanted to find a way to install the harmonic balancer without being a dork and hammering it on.
Yeah, I know that a tool exists to do this but I enjoy finding other ways.
Grainger had 12” all thread for nine bucks.

View attachment 1716397094

I cut it in half to make two of these. I just welded a 3/4” socket with 1/2” drive….

View attachment 1716397095


In theory, it should thread in by hand but the socket will help keep the crankshaft still while turning the nut..

View attachment 1716397096

There is a thick washer, a bearing and another thick washer to press against the balancer.

View attachment 1716397097

I had the hardware so this was an easy one. This will work on big blocks too.

That's slick! Plus, for storage you can sandwich everything with the nut so you don't lose the washers and bearing.

 

[Kern Dog]

I'd bet the gasket diameter makes a bigger difference at the thicknesses you're looking at.

Good point. I might lay one on the block tomorrow to get a look. Anything that increases volume will reduce compression.

That's slick! Plus, for storage you can sandwich everything with the nut so you don't lose the washers and bearing.

I get accused of being a cheapskate but sometimes I just like to figure out a method or make a tool rather than just buying things.
Hey… are you going to Spring Fling?
The wife and I are heading south on Wednesday!

 

[Kern Dog]

I paid a little extra for Edelbrock head gaskets.

I had some Fel Pro gaskets here but like a dummy, I thought a gasket from Edelbrock might be a little better since they make a lot of great aluminum heads. I compared the bore sizes to a Fel Pro. The gray gasket is the Edelbrock.

Every dimension came up the same. I looked closer…

Well, they should be the same since they share the same damned part number.

They even have the “Permatorque” script on both gaskets. You know, the one that Fel Pro uses.
I have no issue with Fel Pro, it was just that I paid for something that I already had here.

 

[mopowers]

I get accused of being a cheapskate but sometimes I just like to figure out a method or make a tool rather than just buying things.
Hey… are you going to Spring Fling?
The wife and I are heading south on Wednesday!

I don't care who ya are - that's not cheap, it's resourceful!

I wish I could go to Spring Fling this year. I'll actually be down in Anaheim for work all next week before having to head up to Redding next weekend for the following week for work. Busy next two weeks for sure. You guys have fun!! You taking the red Charger?