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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
I dropped the engine and trans off for rebuild. 351W and an FMX, both 1973. I've instructed the builder to target a static 10:1 with his piston selection, heads are 60.4cc comb chambers. He's looking for direction on the cam, I've been looking at comp cams XE262H. http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=877&sb=2That's probably as wild as I care to go, We will be running a dual plane alum intake and prob 600-650 vac secondary 4 barrel, headers too, probably something mid length. I like the lunati voodoo cams but I cover so many bases, being the body man, mechanic, painter etc. I want to buy a complete set including valve springs and I don't know that lunati offers it. I'd like to run stock converter, this is a power assist brake car, weight is around 3000lbs, gears I believe are 3.23 (or possibly 3.5). 10:1 compression. The stock cam for 1969 351M in Mach1 would have been ford #C9OZ-6250-A Lunati sells kits I'm pretty sure. The Comp cam you linked is actually one size bigger than I'd be inclined to go. How about this: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=876&sb=2Or to still have livelier lobe shapes than similar OEM cams, but not quite as demanding on other valve train parts as the Xtreme Energy series: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=886&sb=2In my estimation you're over cooking it with the 10:1 compression idea, particularly with iron heads. The kind of cam that will be compatible with modest gears, a stock converter, and nice driving characteristics will produce a lot of cylinder pressure and even pump premium is going to have trouble.
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
But I don't want roller. lol Call ford? I'm thinking they might have more than one phone number.
Something clever here.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
If the engine hasn't run in a good while I'd pull it and do a complete disassembly and thorough cleaning. All new gaskets, seals, yadda yadda.
Same with the carb.
I'd be tempted to replace the valve springs too. WHAT! no cam recommendation? You're slipping! I didn't think the 390 was up for a rebuild.
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
I dropped the engine and trans off for rebuild. 351W and an FMX, both 1973. I've instructed the builder to target a static 10:1 with his piston selection, heads are 60.4cc comb chambers. He's looking for direction on the cam, I've been looking at comp cams XE262H. http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=877&sb=2That's probably as wild as I care to go, We will be running a dual plane alum intake and prob 600-650 vac secondary 4 barrel, headers too, probably something mid length. I like the lunati voodoo cams but I cover so many bases, being the body man, mechanic, painter etc. I want to buy a complete set including valve springs and I don't know that lunati offers it. I'd like to run stock converter, this is a power assist brake car, weight is around 3000lbs, gears I believe are 3.23 (or possibly 3.5). 10:1 compression. The stock cam for 1969 351M in Mach1 would have been ford #C9OZ-6250-A Lunati sells kits I'm pretty sure. The Comp cam you linked is actually one size bigger than I'd be inclined to go. How about this: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=876&sb=2Or to still have livelier lobe shapes than similar OEM cams, but not quite as demanding on other valve train parts as the Xtreme Energy series: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=886&sb=2In my estimation you're over cooking it with the 10:1 compression idea, particularly with iron heads. The kind of cam that will be compatible with modest gears, a stock converter, and nice driving characteristics will produce a lot of cylinder pressure and even pump premium is going to have trouble. Well lets talk about that compression then. That's a static ratio that I've pulled out of the air based of the original. But, things were different back then, things like fuel for one. Should I look for pistons with a little more relief volume? Maybe get down in the 9.5 range? I mean seriously, I'd like to hit 300 hp with a fairly smooth idle, good vacuum, stock converter etc. And I'd liek to do so with all things considered, such as today's fuel and modern cam grinds.
Something clever here.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
Well lets talk about that compression then. That's a static ratio that I've pulled out of the air based of the original. But, things were different back then, things like fuel for one.
Should I look for pistons with a little more relief volume? Maybe get down in the 9.5 range?
I mean seriously, I'd like to hit 300 hp with a fairly smooth idle, good vacuum, stock converter etc. And I'd liek to do so with all things considered, such as today's fuel and modern cam grinds.
Your goal is quite reasonable. I might even go closer to 9:1 compression. Are the heads getting any work beyond new guides and a stock type valve job?
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
With a vacuum secondary carb you can go to 750 cfm no problem.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
That has to be a closed combustion chamber design give the small cc volume you listed. Make sure the engine man sets things up so the quench area is set up with piston deck to head clearance toward the tight side. Safe clearance mind you, but tight. That's one way of getting the most out of lower compression set ups.
Another is ignition timing. I don't have that much Ford experience, but pump gas friendly compression Chevys like a bit more than stock initial advance, and with the rest of the curve coming in relatively quick. But in doing this you have to make sure the curve doesn't put in too much total advance at the top.
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
Are the heads getting any work beyond new guides and a stock type valve job?
We don't know if we have hard seats (73), hardened seats are a possibility if they aren't there already. Talked about screw in rocker studs, but that's about it above a general once over. Nothing exciting like porting.
Something clever here.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
You could port match to the new manifold easily enough.
How about a multi-angle valve job?
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Joined: Mar 2012
Posts: 6,519
Campfire Tracker
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Campfire Tracker
Joined: Mar 2012
Posts: 6,519 |
If the engine hasn't run in a good while I'd pull it and do a complete disassembly and thorough cleaning. All new gaskets, seals, yadda yadda.
Same with the carb.
I'd be tempted to replace the valve springs too. He drives it once a month or so. Sometimes takes it out to go to the VFW, but not as often in the winter. It will not be sold. This is staying in the family. I just want to make sure we're giving him a fair amount so that the feds don't come back looking for more money after he passes. He's an interesting guy. Has only been away from home 3 times. He was drafted to go to Vietnam. Is very non-verbal (we think Asbergers, but he's nearly 75, so no one even knew what that was decades ago). I can only imagine his time in the army was a little like Forrest Gump. He'd do what you tell him and I can imagine his platoon buddies keeping an eye on him. The other two times he went to the Black Hills with my Father in Law and their folks. Outside of that, he's never been outside the county. He worked on the family farm his entire life until they sold it and retired, then he worked as farm labor another 10 years or so until his body broke down. That car is funny. Never took the plastic off the seats, never took the plastic off the seat belts. I'm pretty sure no one has ever sat in the back seat and I think only his mother sat in the front the odd times he would drive it to the store with her. He's gonna be one of those guys that has $100,000 stuffed in coffee cans or mattress, or maybe he only has a few quarters to rub together. Nobody will know until after he passes.
"And for the support of this Declaration, with a firm reliance on the protection of divine Providence, we mutually pledge to each other our Lives, our Fortunes and our sacred Honor."
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
And yes it's a closed chamber. We should be able to squish things pretty good even if we drop to a 9:1 if our relief volume is cut into the "open" side of the piston head.
Something clever here.
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
You could port match to the new manifold easily enough.
How about a multi-angle valve job? I consider the multi angle pretty standard practice, definitely yes.
Something clever here.
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Joined: Dec 2015
Posts: 840
Campfire Regular
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Campfire Regular
Joined: Dec 2015
Posts: 840 |
But I don't want roller. lol Call ford? I'm thinking they might have more than one phone number. What if a roller set could be had for not much more than what you are planning to pay now? I no longer build a strong motor without a Roller Valve Train. The difference is incredible, A Friction Valve Train can rob up to 20% or more of your potential output from an Engine. If you are willing to check it out I will try to find you the connection to these parts as a fellow Ford Fan. I was weaned on building swap out Exchange Motors for "Weekend Bracket Racers" and currently do personal custom dynamics work for the same as my principle occupation.
When I no longer have the right to protect my own person or property...my person and property have become public property in common.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
And yes it's a closed chamber. We should be able to squish things pretty good even if we drop to a 9:1 if our relief volume is cut into the "open" side of the piston head. That's the way to do it.
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Joined: Dec 2015
Posts: 840
Campfire Regular
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Campfire Regular
Joined: Dec 2015
Posts: 840 |
I dropped the engine and trans off for rebuild. 351W and an FMX, both 1973. I've instructed the builder to target a static 10:1 with his piston selection, heads are 60.4cc comb chambers. He's looking for direction on the cam, I've been looking at comp cams XE262H. http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=877&sb=2That's probably as wild as I care to go, We will be running a dual plane alum intake and prob 600-650 vac secondary 4 barrel, headers too, probably something mid length. I like the lunati voodoo cams but I cover so many bases, being the body man, mechanic, painter etc. I want to buy a complete set including valve springs and I don't know that lunati offers it. I'd like to run stock converter, this is a power assist brake car, weight is around 3000lbs, gears I believe are 3.23 (or possibly 3.5). 10:1 compression. The stock cam for 1969 351M in Mach1 would have been ford #C9OZ-6250-A Lunati sells kits I'm pretty sure. The Comp cam you linked is actually one size bigger than I'd be inclined to go. How about this: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=876&sb=2Or to still have livelier lobe shapes than similar OEM cams, but not quite as demanding on other valve train parts as the Xtreme Energy series: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=886&sb=2In my estimation you're over cooking it with the 10:1 compression idea, particularly with iron heads. The kind of cam that will be compatible with modest gears, a stock converter, and nice driving characteristics will produce a lot of cylinder pressure and even pump premium is going to have trouble. Well lets talk about that compression then. That's a static ratio that I've pulled out of the air based of the original. But, things were different back then, things like fuel for one. Should I look for pistons with a little more relief volume? Maybe get down in the 9.5 range? I mean seriously, I'd like to hit 300 hp with a fairly smooth idle, good vacuum, stock converter etc. And I'd liek to do so with all things considered, such as today's fuel and modern cam grinds. 10 to 1 and add a half gallon of Diesel per tank full of what they sell now as Gasoline.
When I no longer have the right to protect my own person or property...my person and property have become public property in common.
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Joined: Oct 2008
Posts: 4,228 Likes: 1
Campfire Tracker
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Campfire Tracker
Joined: Oct 2008
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I used to do that a very long time ago, didn't know anyone else did that.
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Joined: Dec 2015
Posts: 840
Campfire Regular
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Campfire Regular
Joined: Dec 2015
Posts: 840 |
I used to do that a very long time ago, didn't know anyone else did that. The Diesel? slows the burn like higher octane fuel does
When I no longer have the right to protect my own person or property...my person and property have become public property in common.
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Joined: Sep 2004
Posts: 14,211 Likes: 1
Campfire Outfitter
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Campfire Outfitter
Joined: Sep 2004
Posts: 14,211 Likes: 1 |
I thought the Cleveland was a better engine. I'm no Ford guy!
Well we're Green and we're Gold, and we play better when it's cold. All us Cheese heads have our favorite superstar. We love Brett Favre.
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Joined: Sep 2004
Posts: 35,293
Campfire 'Bwana
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OP
Campfire 'Bwana
Joined: Sep 2004
Posts: 35,293 |
I don't know if it's really "better"
Something clever here.
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Joined: Jun 2004
Posts: 44,908 Likes: 13
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,908 Likes: 13 |
For straight top end power the huge port Cleveland 4 bbl. heads work pretty well. But for the majority of the time they're not what you want for a milder engine combination in a street driven car.
When the engine isn't going full bore all those big ports are doing is dampening signal to the carb, reducing part throttle driveability. Also, a modest cam that's appropriate for a project such as Dave has outlined won't be making power in the rpm band where the huge port heads would provide an advantage feeding only 351 cubic inches.
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