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James_Douglas

A shot across the bow, Exhaust Seats and Valve Guides

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Hi all,

 

As I write up the preliminary specifications for the rebuilding of my 265 flat head, I wanted to let people know that I am looking into have a set of special exhaust valve seats made that are much better than what is generally available. These will carry away more heat than the stock or current replacement seats. In addition, I will also be having made some special formula bronze valve guides. The maker thinks they can also place internal to the guide seals on the intake side.

 

Also, I am looking to having them make some lifter bore bronze inserts to get the bores back to STD.

 

Now these items are likely to be expensive. But, I wanted to let people know I am looking into it and will most likely move on it in the early summer when the engine work starts.

 

In the event anyone wants to piggy back on what I am doing let me know via PM and I will create an email list and let people know when I move on this.

 

James.

Edited by James_Douglas
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my advice to you would be to spend your money on other aspects of your rebuild..... like balancing.  The guides and seats cause very little trouble

and your block will accommodate a .060 overbore.  Cast iron is the preferred material for sleeves.

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On 1/21/2020 at 6:00 PM, dpollo said:

my advice to you would be to spend your money on other aspects of your rebuild..... like balancing.  The guides and seats cause very little trouble

and your block will accommodate a .060 overbore.  Cast iron is the preferred material for sleeves.

Amen Dave 

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Of course the engine will be balanced and more. How many hours have you guys driven your flat-head engines in brutal stop and go traffic with a fluid coupling or a torque converter?

 

Even Chrysler stated in service bulletins to not leave a car in gear and on the coupling for more than five minutes stopped. I have seen in my car, and others, heating issues in such modern traffic on hot days creeping up to the Bridges into San Francisco or when there is a highway accident and everything is inching along at 5 MPH.

 

The point of using better, thermally speaking, exhaust seat material is to draw more heat out of the combustion chamber. There is mountains of data on this subject should one wish to go read it. Now, no one item is going to make that much difference. But when you add up all the little items, you can make a good dent in dead stop heat removal from the engine. The bronze valve guides also do the same thing on the exhaust side. As a bonus, the intake side can be fitted with seals.

 

In addition to seats and guides, I will be using an electric water pump to keep the flow constant at lower RPMs.  An electric (2) radiator fan will also run at full RPM at idle and at slow speeds.  The entire point is to engineer a system of items so that the engine will stay dead on at 180F sitting in gear at idle on a freeway on a 110F day.

 

James.

 

 

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42 minutes ago, James_Douglas said:

The entire point is to engineer a system of items so that the engine will stay dead on at 180F sitting in gear at idle on a freeway on a 110F day.

 

I think I would want something to keep the driver cool on a day like that.......maybe a late-model F150......    😁

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I live in west Texas, it gets darned hot here in the summer.  Now granted I don't sit in stop and go traffic or run it for hours on end on the freeway but I have yet to have an overheating problem.  All said, I say go for it.  I am all for updates to our engines.

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Im all for updates too, however some are complicated and really become a point of diminished returns. 

For the masses the Chrysler Flathead 6 engine as we know has given great dependable service since 1938, as its 2020 thats simply amazing.

 

For the OP Douglas James,

my suggestion is to say -  Hey when you finally get your ultimate engine built,  shoot a video of it on a floor dyno and then how it is for miles per gallon and in traffic etc and then document it all and post it up...  actually James why don't you get a blog and post it all up there.

 

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I have had some issues on very hot summer days, traffic or highway accident, and overheating with the fluid drive. I added an electric fan that I control manually that helps as well as disengaging the clutch.

 

This is not quite on the subject at hand, but, I have seen where some folks go the Chevy valves. What is the advantage to that?

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The biggest advantage to Chevy valves is availability; there are millions of them out there!  They also have more modern metallurgy.  They generally need to be turned down to Plymouth diameters, and you need to use Chevy valve locks.

 

Marty

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where do you get an electric water pump? my engine gets very hot in city traffic and I think that the water flow at idle at the stop lites is so little that more water flow would be a great help.    capt den

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1 hour ago, captden29 said:

where do you get an electric water pump? my engine gets very hot in city traffic and I think that the water flow at idle at the stop lites is so little that more water flow would be a great help.    capt den

Most of the shops that sell drag racing mods will have them.  Will require some work to fit it up because most are intended for Ford/Chevy motors

 

That said, I'd suspect inadequate idle airflow is more to blame.  Auxiliary electric fan would be cheap and easy to try.

Edited by kencombs

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I've seen kits that use a motor to run your stock water pump.  Of course that means you will need an electric fan too. 

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2 minutes ago, Sniper said:

I've seen kits that use a motor to run your stock water pump.  Of course that means you will need an electric fan too. 

 

And an alternator.....

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What my Gramps would do with his chryslers was to install an extra heater core inline before the cabin heat under the passenger side floorboard, protected of course and run it at full blast during the summer months to keep the cooling system from boiling over.

Crude but effective.

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On 1/28/2020 at 9:11 AM, martybose said:

The biggest advantage to Chevy valves is availability; there are millions of them out there!  They also have more modern metallurgy.  They generally need to be turned down to Plymouth diameters, and you need to use Chevy valve locks.

 

Marty

Marty,

Any chance you could post pics of Chevrolet valves in your engine build(s).

Pics can offer insight to the rationale of using GM valves over stock...

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Our late member Don Coatney used Chev valves in the 25" De Soto engine he built and installed in his P15, apart from the price, the pics he posted showed valves that had a more tuliped profile so may have allowed the engine to breath a fraction more..........andyd 

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49 minutes ago, Andydodge said:

Our late member Don Coatney used Chev valves in the 25" De Soto engine he built and installed in his P15, apart from the price, the pics he posted showed valves that had a more tuliped profile so may have allowed the engine to breath a fraction more..........andyd 

Yes recall some of his pics.

Not sure he actually built the engine. But most likely ran it on floor before installing it.

Have no idea who built that engine.

 

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On 1/30/2020 at 7:04 PM, greg g said:

Don posted many pictures of his engine in various positions as he put it back together.  Don't know who did his machine work but he did most of the reassembly.  

Don building flathead 6s?

received_174064433903012.jpeg

received_879284312504700.jpeg

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30 minutes ago, greg g said:

His engine was blue, with dual carbs.

Im sure it was at some point.

But this is a pic of Don at somebody's shop building a flathead 6.

Not sure if this was his and later painted blue and when he bought a dual intake and exhaust from George Asche.

This engine definitely did not have Chevy valves though. 

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