A shot across the bow, Exhaust Seats and Valve Guides

[Sniper]

Being concours you maybe limiting your solutions.  A shroud will likely fix the issue, but it's not concours.  Maybe a two piece one that can be easily removed.

[classiccarjack]

On 1/27/2020 at 8:21 PM, Sniper said:

Small town advantage to me.  ?

I actually get the best of both worlds....

 

Small townville Kansas and San Diego...

[Sniper]

I spent 10 years in San Diego, when I wasn't at sea, which was about half that time.  Left in 94.  Very pretty place and some times I miss it.

[Matt Wilson]

On 2/5/2020 at 8:49 AM, James_Douglas said:

I will also be sleeving the lifter bores back to factory size. Those sleeves will be a bronze alloy as well.

 

James.

The sleeving of the lifter bores has me intrigued because I have several lifter-to-bore clearances that are well beyond factory limits, and I've been thinking of having the bores sleeved.  I've looked around online and have only found sleeves for the common Ford, Chevy and Dodge V8 lifter sizes.  I suppose I woild have to have them custom-made for my 265.  Not sure who would do this.

 

Also, I've read comments on several forums (mostly race forums), where people have said bronze lifter sleeves are not necessarily that good for street applications, and often don't last as long as cast iron sleeves.  Others say that bronze does fine for street if they are done correctly.  It seems to me that bronze would be best regardless, but I'm no expert.  No doubt, there are certain types of bronze alloys that are better than others, but I don't know what those are.

 

What kind of clearances would you be aiming for?  Standard factory clearances?  I have one manual that calls for 0 - 0.0007", which seems rather tight, and another manual that calls for 0 - 0.001", which still seems somewhat small, even on the high side of that range.  The wear limit in one manual is 0.0015, and in another manual, it's 0.002", if I recall correctly.  Modern lifter specs typically call for just under 0.001 on the low end (again, pretty tight to me) to about  0.002" or slightly more on the high end, for new parts, but those lifters are larger diameter than ours, so greater clearance my be warranted.  Also, I'm not sure how the use of bronze sleeves might affect the required clearance.

 

I'd appreciate any thoughts you have on any of this.

[James_Douglas]

On 2/5/2020 at 12:43 PM, Sniper said:

Being concourse you maybe limiting your solutions.  A shroud will likely fix the issue, but it's not concourse.  Maybe a two piece one that can be easily removed.

Sniper with respect, you may have missed something. The 1949 Desoto Convertible is the Concourse Restoration. The 1947 Desoto Suburban is the car we will use to tour the USA. That is the engine we are talking about to modify.

 

James.

Edited February 7, 2020 by James_Douglas

[James_Douglas]

2 hours ago, Matt Wilson said:

The sleeving of the lifter bores has me intrigued because I have several lifter-to-bore clearances that are well beyond factory limits, and I've been thinking of having the bores sleeved.  I've looked around online and have only found sleeves for the common Ford, Chevy and Dodge V8 lifter sizes.  I suppose I woild have to have them custom-made for my 265.  Not sure who would do this.

 

Also, I've read comments on several forums (mostly race forums), where people have said bronze lifter sleeves are not necessarily that good for street applications, and often don't last as long as cast iron sleeves.  Others say that bronze does fine for street if they are done correctly.  It seems to me that bronze would be best regardless, but I'm no expert.  No doubt, there are certain types of bronze alloys that are better than others, but I don't know what those are.

 

What kind of clearances would you be aiming for?  Standard factory clearances?  I have one manual that calls for 0 - 0.0007", which seems rather tight, and another manual that calls for 0 - 0.001", which still seems somewhat small, even on the high side of that range.  The wear limit in one manual is 0.0015, and in another manual, it's 0.002", if I recall correctly.  Modern lifter specs typically call for just under 0.001 on the low end (again, pretty tight to me) to about  0.002" or slightly more on the high end, for new parts, but those lifters are larger diameter than ours, so greater clearance my be warranted.  Also, I'm not sure how the use of bronze sleeves might affect the required clearance.

 

I'd appreciate any thoughts you have on any of this.

 

Matt,

The company I am talking to about this is:  https://www.cheprecision.com/

 

These folks are not inexpensive. Probably too expensive for most people to use given the Benefit-Cost of their parts. In my case, given the use and my experience in particular with the stock valve guides, the cost is worth the benefit to me. The clearances for the lifter bores or the valve guides will be guided by their recommendations.

 

One thing to keep in mind is the very "direct" angle of the valve train in these cars. As such, I think we can run tighter tolerances using their materials.  I have been toying with the idea to use sodium exhaust valves as well with the bronze guides.

 

My time line to those parts will be in about 3 to 4 months. They will not provide any pricing until I send them a print for the lifter bores and I will send them an actual guide.

 

James.

 

Edited February 7, 2020 by James_Douglas

[Sniper]

3 hours ago, James_Douglas said:

Sniper with respect, you may have missed something. The 1949 Desoto Convertible is the Concourse Restoration. The 1947 Desoto Suburban is the car we will use to tour the USA. That is the engine we are talking about to modify.

 

James.

 

 

I did miss that, makes things easier then.  Fitting a shroud may very well be your solution.  I know my 64 300 would exhibit low speed/idling issues in heavy traffic issues till I put a shroud on it.  Even an oversized radiator didn't help.

[Frank Elder]

Now you are toying with something interesting to me.... @James_Douglas I've always thought that the lifter bores could use some sort of sleeve to make them closer tolerance.....would oilite/sintered bronze be too soft? Some sort of speedy sleeve....lol.

[Sniper]

Update on running hot.  My 51 never ran hot, till today.  In fact it ran cold, never got much above 150 degrees.  I figured it was either the wrong thermostat in there, no thermostat or one that was stuck open.

 

I was wrong.

 

There was a thermostat in it, a Delco one rated for 180 degrees.  It was installed upside down.

 

Near as I could figure the water pressure was sufficient to unseat the valve and kept the engine running too cool.  The valve was definitely seated when I pulled it.

 

I swear the mechanic that maintained this car before me was a world class hack.  Everything he touched was poorly and incorrectly done. 

 

While I had the coolant drained to change the thermostat I took advantage of it to pull the radiator so I could clean off the timing marks on the pulley and check my timing.  It was too tight to do a good job otherwise.

 

Timing was set to 30 degrees advanced, at idle speed of 550 rpm.  Wow.

 

So now I am running at about 200 degrees, on an 80 degree day.  This was with a lot of low speed driving around a parking lot, teaching my son to drive.  In a 51 Cambridge with no power anything, three on the tree.  He did pretty well though I think I did pick out the smell of clutch.