PDA

View Full Version : Padding a 44 cube merc-



rumrunner
04-19-2010, 08:41 PM
O gurus of phantom black?

Mark75H
04-20-2010, 04:57 AM
You can do the porting yourself. Raise both sides .060" and square the tops of the ports. Make a scribe line with a piston ring as reference and stay on it.

Boring and using oversize pistons will make no noticeable difference other than in your bank account.

You can do the welding yourself ... it is done from the outside.

One problem I see is that no one pads a 44 for 93 octane ... you are in experimental territory. I think the block you are starting with has a little pad in it that would have to be taken out to weld in something new, that will be exotic work.

Since you have a lot of blocks to work with, you might consider mashing the heads instead.

Skoontz
04-20-2010, 06:25 AM
Ok, got a question here....Since I know very little about Mercs except they have got dead end holes ( non removable cylinder heads ) have there have been higher tops made into the pistons in place of padding a cylinder? I know adding just a top will only raise the compression so much, where padding removes space from all the chamber.

It seems like that would be the way to go rather than all the welding and such with padding.....

A/B Speedliner
04-20-2010, 06:52 AM
Doug Kay has been sucessfull in maching off the low compression cylinder tops and welding on padded heads.
David

formeone
04-20-2010, 08:08 AM
squishing the heads uggggg havent seen that for years since it seemed they all blew up when done ,,, at least around this neck of woods..

Fastjeff57
04-20-2010, 09:50 AM
1. You'd be FAR better off to find yourself a later, off-set plugs block and start from there. You can find blocks that used the same distributor, which makes your job easier. They have massive padding and more comp ratio to begin with, so you start with something easily as good as a padded, center plug 44. (Agreed, Sam?) My 67 vintage 44 is a great runner.

2. PTs in America were NOT powered my "Merlins"--only a few British MGBs and MTBs got to use marinized Merlins. American PTs used Packard V-12s based on a water cooled version of the WW I Liberty V-12 (designed in a motel room by a few engineers in 4 days!)

Jeff

Mark75H
04-20-2010, 03:14 PM
1. You'd be FAR better off to find yourself a later, off-set plugs block and start from there. You can find blocks that used the same distributor, which makes your job easier. They have massive padding and more comp ratio to begin with, so you start with something easily as good as a padded, center plug 44. (Agreed, Sam?) My 67 vintage 44 is a great runner.

2. PTs in America were NOT powered my "Merlins"--only a few British MGBs and MTBs got to use marinized Merlins. American PTs used Packard V-12s based on a water cooled version of the WW I Liberty V-12 (designed in a motel room by a few engineers in 4 days!)

Jeff

Yes there is confusion about Packard building Merlin engines ... because they did build Merlins for other applications, most notably the P-51B and later variations of the Mustang. Packard was the only manufacturer ready to build more V-12's - Allison was already making as many as they could.

http://www.ptboats.org/20-01-05-ptboat-008.html
http://www.mustangsmustangs.com/p-51/p51specs.shtml

The offset plug motors do have a different combustion chamber and pads ... BUT ... the compression is exactly the same ... 22 cc's

I am sure Mr Kay's work is great, but I'm also sure its not in the price range that rumrunner is considering for a play motor.

High compression pistons would work, but you have to order hundreds at once and you have to have a work ready die that can double the cost of production if you don't .... $2,500 or more ... for a few modified motors, its easier, faster and cheaper to modify the motor and run stock pistons.

jeff55vDSH
04-20-2010, 05:20 PM
How much H.P. do you hope to get from these mods? Without a set of open megaphones, I would guess maybe 5hp. And you'll lose a lot of bottom end power.
If it were me, I'd try slipping a 65hp Merc under a 50hp cover or decals.
But that's just me.
:)

Mark75H
04-20-2010, 05:35 PM
I agree the hp increase may only be 5 or 6 ... but I disagree that there will be any noticeable loss of bottom end at all ... unless you are trying to pull skiers or run a 2,000 pound boat

Art Kampen
04-20-2010, 06:18 PM
Just happen to have a 44 block that has has been padded and ported,along with the pistons for it. If you are interested let me know. Maybe we could work out a deal.:):)
Art Kampen

Mark75H
04-20-2010, 06:28 PM
Art he wants one that will run on 93 octane gas ... that was one of the requirements. That would probably be about 19-20 cc's ... I bet yours is closer to 15

genea01
04-20-2010, 06:30 PM
squishing the heads uggggg havent seen that for years since it seemed they all blew up when done ,,, at least around this neck of woods..

i have seen it done and it worked i ran the motor i do agree that it is very hard and it is a art so get the right person to do it

mercguy
04-20-2010, 08:19 PM
i have seen it done and it worked i ran the motor i do agree that it is very hard and it is a art so get the right person to do it


Jim Ruck is the man to "smash it"............

rumrunner
04-22-2010, 01:27 AM
How much H.P. do you hope to get from these mods? Without a set of open megaphones, I would guess maybe 5hp. And you'll lose a lot of bottom end power.
If it were me, I'd try slipping a 65hp Merc under a 50hp cover or decals.
But that's just me.
:)

"But thats just Me".....Every one has an opinion. Thats your prerogative:rolleyes:. >5 HP?< - for a big bore, big carb, worked tuner, high compression, ports worked, timing tweeked and plastic reed mota? 5 HP?? Is that what your engine builder tells you? (HEHEHEHEHEHE) Sheeesh.....I could give a bat's poot less how many HP this thing puts out. The GPS tells the tale. I ain't got no class rule book to follow. And...BTW...if I was gonna "slip something under the cover" - It would be a big inch 40 yammy or 'hatsu powerhead (ain't no problem..we can do that..) with a Merc cowl wrap. But I love the old skool Mercs. This is my personal mota. The composit head/block skeers the heck out of everybody. I AM gonna "pad" it. I'm gonna punch it. I'm gonna put the big carbs on it. I'm gonna work the tuner. I'm gonna polish the crankcase and internals. I'm gonna run it and play with the timing. Then it's going to the river. For fun. If it don't ring the GPS - I'll build a 'nuther 'un. If it pukes, read last sentence. If I don't get but five horsepower with all this work it might take a while, and if it pukes, look up a few lines......how much diff on the GPS do you think? If it pukes, skip up a few lines, I said sumpthin' about building another one.Its runnin' about 52 now. Fishin bote. Totally wore out. Seals ain't been broke. 1979 model. I'm bettin "my way" close to 60. I'm thinking new prop..... Now if I can git me one uv them thar racin' boats ya'll run.....YEEEEEEEHAWWWWWW......and if it pukes, you know what I'll do, right?

Mark75H
04-22-2010, 04:45 AM
Keep us up to date on your progress

A/B Speedliner
04-22-2010, 05:28 AM
I wish I could understand 50% of what he said. Must be getting old.