Well, that was disappointing...

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Rettax3
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Well, that was disappointing...

Postby Rettax3 » Tue May 01, 2018 12:27 am

I took a break this afternoon from the DOHC-Z project. I found this on my old Plymouth's engine: :o
400 Cam Bearing1a.jpg

This is not the original 383 Big Block from my car, which is sitting on a stand too. This is a replacement Big Block I bought a couple of years ago to drop into the car while the 383 was being rebuilt (and yes, 'BUILT'). But, it turned out to be a fairly fresh rebuild already, and I liked this engine after I picked it up and found how clean it was (as you can see in the pics, the inside is spotless except for some minor surface-rust in the water passages), so I decided to build it a little first. It is the same block as my 383, but with heavier castings and the biggest slugs Mopar used back then, 90-thousands more than the 383 and even bigger than the famed 440. I bought a new Lunati VooDoo cam for it over the winter, and a gear-drive set to go with it (Mopars are notorious for stretching their chains -they still run fine, but not necessarily ideally). I thought the cam bearings would be new with the rebuild, and was ready to slide in my new cam and lifters. Nope. Looks like water damage to me, I am afraid of what the crank bearings look like. I scoped the cylinders when I bought the engine, and they are great.
Lunati Cam 1a.jpg

Yep, that definitely crimped my plans for the evening... Every time I move forward on this thing, I get set back half a pace. BACK TO THE BERETTA!


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Rettax3
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Re: Well, that was disappointing...

Postby Rettax3 » Tue Jul 24, 2018 4:18 am

I finally snuck off the other day to replace the camshaft bearings in the old Mopar. I had searched a little and gotten the multi-layer babbit bearings I wanted. The gear-drive set I bought is adjustable, the alignment dowel (arrow) has multiple off-center inserts to micro-adjust the cam timing. The Lunati cam I bought has the performance-style three-bolt mount, vs the stock-type single-bolt. Interestingly though, Lunati uses 3/8" bolts, the timing gears were supplied with 5/16" bolts although the holes were big enough for 3/8s. I will have to get a couple more Grade-8 bolts -I could only find one of the right length in my stash... It is getting closer!
400BBM Timing Gears 1b.jpg


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Well, that was disappointing...

Postby GT_Indy » Tue Jul 24, 2018 10:33 am

Looks good to me. lol.
I wonder if straight gears like that is better or more reliable than using a timing chain, or a double roller chain.
Do you think grade 8 is strong enough for that?


96 Beretta Z26 swap
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Re: Well, that was disappointing...

Postby Rettax3 » Tue Jul 24, 2018 6:38 pm

GT_Indy wrote:Looks good to me. lol.
I wonder if straight gears like that is better or more reliable than using a timing chain, or a double roller chain.
Do you think grade 8 is strong enough for that?

Thanks. Especially with Mopar engines, chains tend to stretch over time, significantly altering actual cam-timing. Vibrations are not good either. The Big Block "B" engines (as opposed to the Big Block "RB" or Raised Block, like the 426 and 440 engines wich have taller decks and longer rods) are rev-happy powerplants, and sloppy chains are just counter-productive. This cam is fairly radical, about the limit for good streetability. With the upgraded valve-springs and the RPMs this engine will see, I don't want 'variable valve timing' or vibrations interfering with reliability or performance. A double-roller chain would be a vast improvement too, but I also like the sound of a noisy gear-set. :wink:

Is Grade 8 strong enough? Well...
On a 3/8" bolt (and this has three of them), Grade 8 is good for over 10,000 pounds of shear force. ARP can do about 400 pounds more -oooo 4%. :roll: Grade 5, which the set was designed for and equipped with, is over 8,000 pounds, but they sent 5/16" bolts which drops the strength to 5750 pounds per bolt. Normally, the stock cam has only one dowel-pin, plus the friction from the center-bolt torquing the timing gear to the face of the cam. This set is nearly press-fit too -it is going nowhere without its' cam... :good:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Well, that was disappointing...

Postby GT_Indy » Tue Jul 24, 2018 9:50 pm

I guess I'm just used to grade 8. I buy grade 8 bolts nuts, and washers for literally everything. Including exhaust. lol.
I know grade 10 is a thing, but I don't know if it can become brittle and fracture from continued stresses and heat changes. I know some bolts are 1 time use, I found that out when I tried to re-use rocker bolts on my olds 455 engine, they twisted when I was torquing them so I had to buy new ones.

That makes me want to redo my olds 455 with gears but I'd have to look into if they offer it or not. I like the gear noise/whine as well. Gear lash sounds not so much, those bug me a bit.

I wonder if a Quad 4 can be converted to gears. LOL. I think it might improve reliability other than the oil pumps tendencies to fail. Honestly, why do they die so often? I look at the Gen2 and Gen3 v6 oil pumps and they work fine, 300k miles and they still pump, but quad4's? They die after like 20k miles. Mind boggling. Makes me want to buy a spare oil pan gasket and oil pump and keep a simple set of tools on hand for daily driving or trips with my gtz. Jack it up, swap it, keep going. lol.

But that is why I like the older stuff as well, simplicity, reliability. As long as it gets oil changes it will keep going.


96 Beretta Z26 swap
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Rettax3
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Re: Well, that was disappointing...

Postby Rettax3 » Wed Jul 25, 2018 1:24 am

GT_Indy wrote:I guess I'm just used to grade 8. I buy grade 8 bolts nuts, and washers for literally everything. Including exhaust. lol.
I know grade 10 is a thing, but I don't know if it can become brittle and fracture from continued stresses and heat changes. I know some bolts are 1 time use, I found that out when I tried to re-use rocker bolts on my olds 455 engine, they twisted when I was torquing them so I had to buy new ones.

That makes me want to redo my olds 455 with gears but I'd have to look into if they offer it or not. I like the gear noise/whine as well. Gear lash sounds not so much, those bug me a bit.

I wonder if a Quad 4 can be converted to gears. LOL. I think it might improve reliability other than the oil pumps tendencies to fail. Honestly, why do they die so often? I look at the Gen2 and Gen3 v6 oil pumps and they work fine, 300k miles and they still pump, but quad4's? They die after like 20k miles. Mind boggling. Makes me want to buy a spare oil pan gasket and oil pump and keep a simple set of tools on hand for daily driving or trips with my gtz. Jack it up, swap it, keep going. lol.

But that is why I like the older stuff as well, simplicity, reliability. As long as it gets oil changes it will keep going.

:D

Quad oil-pumps are, well, interesting. I've only had one fail, and yes, it caused the death of the crankshaft within about five seconds of pressure-loss, thanks Oldsmobile! Phenolic driven-gear on the pump, presumably used so that if the pump seizes (like mine did) it doesn't destroy the drive-gear on the crank (of course my crank was ruined anyway), and it is also quieter and to a degree self-lubricating. Interesting concept -some old engines actually use a similar phenolic gear for the cam, just to go full-circle. Honestly, my Quad (a L.L.L.L.O. SOHC variant) had something like 180K on it, I doubt the pump had ever been changed, and I know the bearings hadn't been. I had looked them over at about 164k, and they were still serviceable, but showing wear. If that engine had brand-new bearings when the oil-pump failed, maybe they would have survived? Or maybe it would have just ruined new bearings...

Oil pump on a Mopar Big Block? RIGHT ON THE OUTSIDE OF THE ENGINE! In fact, the oil filter screws directly onto it on the front. Piece of cake to swap, could probably do it in five minutes with some practice. :good:
BBM 400 Oil Pump 1b.jpg


Grade 10? I used to know hardware pretty well, I've never heard of a Grade "10". Metric has Class 10.9, closely equivalent to SAE Grade 8 for strength. AN hardware (Aviation) is more consistent in strength and quality, and MS (Mil Spec, used in commercial aviation and military applications) is stronger still.

Very few bolts are truly one-time use, although Torque-To-Yield bolts certainly are (like Quad head-bolts :roll: ). It doesn't mean they are still good after years of punishment though...


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Well, that was disappointing...

Postby GT_Indy » Wed Jul 25, 2018 5:24 pm

Wow that makes it easy to replace on the mopar.

Yah I'm considering adding a oil pressure cut out to my 90 gtz, so if the pressure is lost, it kills the ignition. Only flaw with that plan is if the clutch is engaged, the engine is still going to spin and risk dying from no oil pressure.


96 Beretta Z26 swap
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Rettax3
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Re: Well, that was disappointing...

Postby Rettax3 » Sun Dec 23, 2018 10:28 pm

I had a little time this weekend to work on the old Plymouth again. I installed my new Lunati lifters, plugged in my pushrods, and bolted-down my lifter-valley cover. My supposedly 'rebuilt' engine is definitely not that. Although it was almost certainly pulled apart, cleaned, and 'refreshed', it still has the OE Chrysler flat-top pistons. This 'not actually rebuilt' explains the camshaft bearings and their damage. I do hope that they at least ridge-reamed and re-honed the bores and put in new seals and rings, but at this point, who knows? I am glad that I have a virgin block though. I'll take that as a plus... It also reassures me that the rotating assembly is at least factory balanced -which is fine for what I will be doing with it (for now, at least). I do not need a 9,000 RPM Big Block Mopar (yet), and my old 383 used to propel my car to 50 MPH in first gear without over-revving. :P

I'm going to spend just a moment waving the Mopar flag here, because although I am more or less a Chevy person, almost every tidbit I learn about the Mopar Big Blocks has me going, 'Hmm, that was smart..' :good:

Unlike Chevy V engines, the BBMs do not have coolant passages entering or exiting through the intake manifolds, so removing them does not cause coolant loss or possible contamination into the oil-pan. Yay! They have a separate lifter-valley cover, a thin stamped steel plate, which also doubles as the intake manifold gaskets (although separate gaskets are also available, should the need arise to supplement the seal. If the valley cover-plate is old and the intake seals crushed, that would be a good time to use the conventional supplementary gaskets, for instance). These covers are also secured front and rear with long skinny plates that bolt down to the block across the ends of the lifter valleys. Ever wish Chevy or Ford did something different at the ends of the lifter valley than, "Apply half a tube of silicone across the ends of the valley and settle the intake manifold down onto it quickly -hopefully this isn't in a van because it has to come basically straight down."? BBMs tend not to leak much from the valley ends... :wink:

The cylinder heads are lubricated in a very different way from the method used by 'everyone else'. Instead of oil being supplied by the valve lifters though the pushrods and up through the rocker arms, the BBM camshafts have a V-shaped tube drilled through one of the journals. This tube directs oil from the oil gallery underneath the cam to ports running into each head (one then the other) as the cam rotates and lines-up the V-tube. From here, the valve rocker-arms (which ride on a single shaft that runs the length of the head from front to rear) are lubricated from this oil as it runs through the rocker-arm shaft and out through supply holes, this also lubricates the top of the pushrods. The one thing I do not like about this setup is the oil running into the heads has to pass through the head gaskets -this is similar to the Quad-Four engines, and I've always found this to be one of the Quads' weak points. I've never heard complaints about the passages through the gaskets causing problems on the Mopars, but it certainly could happen. One of the interesting things about the Mopar design however is that the pushrods do not have oiling holes on each end, but appear solid (stock pushrods are hollow, for weight reduction and rigidity). Stock lifters also do not have an oiling hole in the top of the lifter (most or all aftermarket ones, including my Lunatis do, so that they can be used in the AMC engines using the same size lifter, and presumably the 'hat' or insert in the top of the lifter could be used in other lifter-bodies for other applications as well). Another feature of this lubrication method is that a builder could install a metering port in the passage to regulate oil flow to the heads, enabling the use of different volume/pressure oil pumps without changing flow characteristics to the heads. Not necessarily better, just interesting and different.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26


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