Refreshing my 440.

celticwarlock

celticwarlock

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After a road trip this weekend, I discovered that the rear main seal in my 440 has really begun to bleed, and I think it's finally time to pull the motor out and replace all the soft parts (and some metal ones, too). It's been weeping for years, but now it's beyond the point where I can live with it.

My car is a '69 New Yorker, and the motor is original. It's never been apart, and it has just 58,000 miles on it. It does not burn oil, make noise, or do anything unusual. It runs rather well, in fact, aside from this worsening leak. I have a plan for what I'd like to do while it's out, and I'd like some opinions.

I plan to tear it down to a short block, replace all the seals and gaskets, have the heads machined for hardened seats, replace the seals, and the valve springs as well. I will be replacing the timing gears and chain, and the cam along with them. I'll probably replace the oil pump also. Everything else will remain in place unless careful inspection warrants additional surgery.

I've got a few questions:

- I intend to use a rope seal, as I've heard that using anything else on a knurled crank can be very problematic. Is this a wise decision? I mean, this one lasted decades, so....I don't see what the disadvantage would be.

- Is there any reason I shouldn't use new steel head gaskets like the ones the motor originally came with?

- I'd like to install a Mopar Performance Purple Shaft. Considering how low the mileage is, would it be necessary to replace the cam bearings? Also, what sort of cam would be best for a cruiser with a bit of grunt? I seem to remember Stan suggesting one cam in particular in a post where he was referencing the 4-speed Formal he put together years ago. I forget what the numbers were, but it seemed perfect for what I have in mind.

I will also be performing a few suspension upgrades along the way as well as some work on the steering box, but my main concern is this 440 of mine (the trans was rebuilt a few years back due to a leak behind the pump and the rear is fine, in case anyone is wondering). Thanks in advance for your input.
 
I am a big believer in the rope style rear main seal for reasons of durability. Usually if a rope seal fails it is because it has dried out, say from the vehicle sitting for years, or the seal has hardened and cracked. A hardened seal is mostly a function of old age and there is not much that can be done about that. Knurled crankshafts tend to eat the after market rubber seals, which were never a good choice except when trying to replace the seal with the engine still in the car. That type of repair never lasts for very long.
The steel head gaskets are probably a better choice if you are going to run any kind of performance cam as using the steel gasket keeps the compression ratio at factory numbers, important to maintain peak performance. The embossed steel gasket also has no sandwich to blow out.
The purple cam shaft is a good street cam, your fuel mileage is however, going to drop significantly if that is an issue for you. Another good cam is the factory "Magnum" cam which maintains adequate vacuum to run the power brakes and the rest of the accessories. All depends on what level of performance you desire and what level of fuel economy is acceptable. Installing new cam bearings is always a good idea to keep the bearings mated to the new cam shaft. If this engine is a 350 hp type with log style manifolds, you should seriously consider some high performance stock manifolds and if you are doing the valve work have the heads ported to match the intake and exhaust manifolds, this will reduce turbulence and get full advantage out of your updated camshaft.
A complete inspection of this engine is a must. Low mileage engines often show inordinate amounts of wear from lots of short trip driving. Engines that are driven in this manner often show significant corrosion of the bearing material, and that is trouble waiting to happen.
If you are going to replace the oil pump, keep in mind that the high volume pumps have an annoying tendency to suck the sump dry when the engine is cold. You would probably be better served staying with a stock pump for what you are doing to this engine now.
Taking time to rebuild the rubber components of the front suspension is also a good idea. I do not recommend using the after market hard plastic bushings in the front suspension as these often have very poor ride quality for a marginal increase in stability.

Dave
 
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celticwarlock said:
I intend to use a rope sea
Click to expand...
I've only had experiences with the modern seals. I've never had one leak using them.

I forget what the numbers were, but it seemed perfect for what I have in mind
Click to expand...
I used a NOS 6 pack cam that I found. I have always felt that was/is the ultimate BB cam for the street. Just enough vacuum at idle to make city driving tolerable especially when your a.c. is puttiing a load on it.
 
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If your really set on using a rope seal the best way to put one in is with the engine out of the car and on the stand with the crank out. Have you ever installed a rope seal? Patience is required when fitting it into the cap. I fit one half in the cap, remove it, install it in the block and fit the other half in the cap. There is a tool to pound it into the cap but a big socket will work also.
 
As far as a cam like the NOS 6 pack is concerned, would my stock carburetor be sufficient (650 CFM) or would I have to upgrade?
 
65sporty said:
If your really set on using a rope seal the best way to put one in is with the engine out of the car and on the stand with the crank out. Have you ever installed a rope seal? Patience is required when fitting it into the cap. I fit one half in the cap, remove it, install it in the block and fit the other half in the cap. There is a tool to pound it into the cap but a big socket will work also.
Click to expand...
I have no experience installing rope seals. If I need to remove the crank, I may use a modern seal after all, but I suppose I'd need one that wouldn't be torn up by the knurling. If so such seal exists, it looks like the crank will be coming out after all, and at that point I'll be putting new bearings in as well.
 
celticwarlock said:
As far as a cam like the NOS 6 pack is concerned, would my stock carburetor be sufficient (650 CFM) or would I have to upgrade?
Click to expand...

The six pack carbs and manifold were rated up to 1100cfm. As a practical matter they would not flow much over 850-900 in stock form at full throttle. That is about all the stock heads and camshaft would support. The 650 Eddy carb as a good choice for your engine as it is now, it will be on the small side if you plan to upgrade later. If that upgrade is several years out, you will probably by better served by the 650 carb.
With some head work on the ports and the Hemi style valve springs and retainers, high performance exhaust, upgraded ignition and a six pack equivalent camshaft, you would be good with an 800-850cfm Eddy or Holly carb on a compatible single plane manifold.

Dave
 
By the time you go thru those 906 heads and install new seats etc, you will have spent most of the price of a new set of 440Source Stealth aluminum heads and you will still have iron open chamber detonation prone heads. Like any aftermarket part they will need to be checked and corrected. Valve job fixed and a little clean up in the bowls is usually all they need OOTB and they should be close to fully ported 906 heads performance wise for less than half the price.

The 6pak cam or similar spec should wake it up. Dwayne Porter can help you spec something appropriate for your application. Maybe similar duration and lobe separation angle with a little more lift to take advantage of the extra flow of those new heads and still be power brake and stock converter happy.

A Thermoquad carb would give you 800 cfm with good cruising economy and great power when economy isn't a priority. A stock TQ intake flows well enough for about 5800 RPM which is about all your list of parts is going to support.

Cam bearings should be good and if the rods and mains don't show any copper, that's good too.

Beware of project creep. It wouldn't be the first Krylon rebuild that turned into a 511 stroker...

Kevin
 
Two stick makes a very valid point in that machine shop work to port and rebuild the 906 heads is fast approaching the cost of the high flow aluminum heads. I guess if you want to maintain a stock appearance, go with your iron heads, otherwise it might make sense to do the aftermarket heads, especially if you decide on a high end build with a stroker kit.
If you use the aluminum heads, be very careful to have the exhaust ports sealed up tight to the manifolds as a small exhaust leak can quickly erode the exhaust port.

Dave
 
With a coat of engine paint the 440Source heads look factory.

Kevin
2001055a.jpg
 
twostick said:
By the time you go thru those 906 heads and install new seats etc, you will have spent most of the price of a new set of 440Source Stealth aluminum heads and you will still have iron open chamber detonation prone heads. Like any aftermarket part they will need to be checked and corrected. Valve job fixed and a little clean up in the bowls is usually all they need OOTB and they should be close to fully ported 906 heads performance wise for less than half the price.

The 6pak cam or similar spec should wake it up. Dwayne Porter can help you spec something appropriate for your application. Maybe similar duration and lobe separation angle with a little more lift to take advantage of the extra flow of those new heads and still be power brake and stock converter happy.

A Thermoquad carb would give you 800 cfm with good cruising economy and great power when economy isn't a priority. A stock TQ intake flows well enough for about 5800 RPM which is about all your list of parts is going to support.

Cam bearings should be good and if the rods and mains don't show any copper, that's good too.

Beware of project creep. It wouldn't be the first Krylon rebuild that turned into a 511 stroker...

Kevin
Click to expand...
The 906 heads will remain.....at least, that is the plan. I'm not going to put headers on the car and I have no intention of roasting the tires regularly, so I really don't see the need for aftermarket heads. In addition, I may or may not change the intake manifold, so it would make even less sense if I went with aluminum heads. Outside of replacing the valve seats, I will be doing much of the work on the heads myself, so I imagine I will save at least some money there.

I'm not interested in buying anything that needs machine work right out of the box. I know I will not get the full benefit of even a slightly larger cam unless I make improvements elsewhere, but I'm not going to do that right away. I could always replace the intake and heads down the road. I'm not in any particular hurry.

As far as project creep is concerned, I will be disciplined. I have to be sure that things don't get out of hand because I have other projects that are underway.
 
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commando1 said:
I really wish people would stop promoting the 440 Source heads.
440 S is a sleazy company.
Click to expand...

How so Stan?

I haven't dealt with them since they moved to Nevada but when Brandon was a one man show he came out to a highway offramp near his home to pick me up well after business hours on New Year's Eve to deliver my 493 kit.

Kevin
 
celticwarlock said:
The 906 heads will remain.....at least, that is the plan. I'm not going to put headers on the car and I have no intention of roasting the tires regularly, so I really don't see the need for aftermarket heads. In addition, I may or may not change the intake manifold, so it would make even less sense if I went with aluminum heads. Outside of replacing the valve seats, I will be doing much of the work on the heads myself, so I imagine I will save at least some money there.

I'm not interested in buying anything that needs machine work right out of the box. I know I will not get the full benefit of even a slightly larger cam unless I make improvements elsewhere, but I'm not going to do that right away. I could always replace the intake and heads down the road. I'm not in any particular hurry.

As far as project creep is concerned, I will be disciplined. I have to be sure that things don't get out of hand because I have other projects that are underway.
Click to expand...

Well you can spend your money any way you see fit but the #1 reason to put an aluminum head on a build like yours is so you can run more than 30 degrees of timing without it pinging like a jack hammer on gas you can buy anywhere. Any extra power is a collateral benefit.

I only suggested the 440Source heads because they have a stock appearance but they don't need machine work OOTB because they are inferior to others, they need machine work because ALL aftermarket heads (and any other parts for that matter) do. There is no such thing as a good mass production valve job.

My machinist has a saying, "If it comes out of a box, it's f#$ked up. That's why I have all these expensive machines here."

My Edelbrock RPM's had a terrible valve job, not it won't run terrible just terrible compared to a proper multi angle job. You will find tight guides on them occasionally too. The best place to find a tight guide is on the work bench not the side of the highway.

If all you want to do is a regrind the valves build on your iron heads, start with some 346 or 452 castings if you want hardened seats. Those already have induction hardened seats.

If when you pull the originals you may find the exhaust valves haven't beat up the seats at all. I've seen them with 200k on them and still be serviceable. It's sustained higher RPM that eats them up like 75 MPH on the interstate driving cross country. They will last a long time with the kind of miles most of us put on them.

Kevin
 
twostick said:
If all you want to do is a regrind the valves build on your iron heads, start with some 346 or 452 castings if you want hardened seats. Those already have induction hardened seats.



Kevin
Click to expand...

This is worth exploring as an option. Ultimately, I will be poking around the Internet for a while before anything is finalized, so it's also possible I might find a pair of aftermarket heads that have already been gone through.
 
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