Stop in for a cup of coffee

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Well I am making some pretty good progress today. Doesn’t everyone incorporate a shooting bench into the handrail on your deck? Sure is slow going wrestling 2x10s by yourself ten ft off the ground. My feet are killing me from the ladder work!

View attachment 1716103342
How far did you keep that deck off of the metal building to be sure that you didn't have issues?
 
How far did you keep that deck off of the metal building to be sure that you didn't have issues?
Right at five inches, I have not chalked it yet and trimmed it so that it is a pretty and a straight line, right now it is just wild. The lumber was really bad and was both different width and length dimensionally. I am putting benches along back side vs hand rail.
 
Stock 273. Solid Cam and lifters... how do I translate cams.. I'm looking at COMP.. there's a

Duration 306/306, Lift .555/.555

Duration 282/282, Lift .495/.495

Duration 270/270, Lift .468/.468


What does all that translate into? The 270/270 spec has an operating range of 1800 -5800. Seems more in alignment with street cruising?

Should I wait until I find out about potential for overbore?

Also, plan is to run the D4B intake and a Holley 4160...600cfm
 
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Stock 273. Solid Cam and lifters... how do I translate cams.. I'm looking at COMP.. there's a

Duration 306/306, Lift .555/.555

Duration 282/282, Lift .495/.495

Duration 270/270, Lift .468/.468


What does all that translate into? The 270/270 spec has an operating range of 1800 -5800. Seems more in alignment with street cruising?

Should I wait until I find out about potential for overbore?
What are you trying to do?
If you're trying for max effort, esp with a vert, need at least 4 point cage, and room for 9" slicks - assuming they can still be had.
 
What are you trying to do?
If you're trying for max effort, esp with a vert, need at least 4 point cage, and room for 9" slicks - assuming they can still be had.

No sir... not a racing application.. cruise it... ability to run 55 for duration... not worried about fuel mileage
 
Just my opinion (paid for dearly)
When looking for max power and good efficiency while doing so, need to look at where the port flow drops off and at minimum know the cc of the heads so actual compression can be estimated with the pistons of choice.

I think there's some factory 273 head flow numbers posted here. If not, certainly some on Stan Weiss's website.
 
I know off the top of my head that factory 340 heads are pretty much done between .480 and .50
No idea what 273 is.
The zebra dart's 318 was a blast off the line. Had a pretty "mild" cam in it. Good for coming off slow and moderate turns. Only real issue was the car was going W2W road racing (summit point, VIR) so Dave needed to set it up more for high rpm. Point of that ramble is big cams are most fun above 3000 rpm, that's usually 65 mph up. Also useful in 1/4 mile.
 
I know off the top of my head that factory 340 heads are pretty much done between .480 and .50
No idea what 273 is.
The zebra dart's 318 was a blast off the line. Had a pretty "mild" cam in it. Good for coming off slow and moderate turns. Only real issue was the car was going W2W road racing (summit point, VIR) so Dave needed to set it up more for high rpm. Point of that ramble is big cams are most fun above 3000 rpm, that's usually 65 mph up. Also useful in 1/4 mile.

Summit Point... right up the road from me..

I'll dig for references on the volume and cam specs. The heads had work done to them previously... haven't been run but was set to go onto a 318 block with purple cam.
 
My goal is to not pay for the same thing multiple times :thumbsup:

Assuming there is some measurement process to determine head volume? And is that a knuckle-dragger thing or does a shop need to determine that?
Head flow is shop. But if your just ballparking factroy, posted on line is good 'nuf.
CC can be done at home or at shop.
Fancy way is with a burette.
I don't see why not use a calibrated syringe.
It's on my todo list...

Plexiglass, some grease, off the top of my head that's it.

Can do the cylinder volume as well. Piston's that come above the deck are a little more complicated.
 
Stock 273. Solid Cam and lifters... how do I translate cams.. I'm looking at COMP.. there's a

Duration 306/306, Lift .555/.555

Duration 282/282, Lift .495/.495

Duration 270/270, Lift .468/.468


What does all that translate into? The 270/270 spec has an operating range of 1800 -5800. Seems more in alignment with street cruising?

Should I wait until I find out about potential for overbore?

Also, plan is to run the D4B intake and a Holley 4160...600cfm
Similar to #2 there a 285 duration .495 lift Crower turned my 289 MoFoCo into a tire frying animal :steering: The 289 heads were far from the best for SBFs.
 
Head flow is shop. But if your just ballparking factroy, posted on line is good 'nuf.
CC can be done at home or at shop.
Fancy way is with a burette.
I don't see why not use a calibrated syringe.
It's on my todo list...

Plexiglass, some grease, off the top of my head that's it.

Can do the cylinder volume as well. Piston's that come above the deck are a little more complicated.

LoL. My thought was exactly that, fill with fluid and measure. I'll just read a bit and swag. I just need to be close
 
The compression get real important when picking cams.
Cams can bleed off or build pressure depending on when the intake valve opens and closes.
Mopar's rod and stroke combination results in less piston time at the top and more at the bottom than (most) other brands.
IMO this means finding someone who understands that when picking a non-mopar cam.
A/J may be off the edge (pun intended) but all that Wallace calculator stuff he posts I think is valuable.

I've bought two 340 engines without knowing the real compression ratio. I will not make that mistake again with the engine sitting on stand now!
And that first one, from RHS (CC's sister company atthe time), needed valve seals a valve job the first couple years I owned it. :(
 
Cams can bleed off or build pressure depending on when the intake valve opens and closes.
That I had read.
Mopar's rod and stroke combination results in less piston time at the top and more at the bottom than (most) other brands.
This I was not aware of
A/J may be off the edge (pun intended) but all that Wallace calculator stuff he posts I think is valuable.
I'll need to do some reading
 
This I was not aware of
Now design a cam for a longer rod MOPAR you have enough extra time to get your valve moving to make a difference AND you can also wait because you have the larger lifter which allows you to open the valve later and still get the flow you need
I know about it only because Shrinker and few others like Wyrmrider have brought it up.

I had it backwards. Mopar's long rod resultrs in the piston dwelling for more time at the top of the stroke, less at the bottom.
So can open the intake valve later (reducing reversion from the exhaust) but then need to shut the intake quicker to keep the compression up.

remember that a long rod engine is more sensitive to intake close than a short rod motor (piston dwell around BDC)
 
Stock 273. Solid Cam and lifters... how do I translate cams.. I'm looking at COMP.. there's a

Duration 306/306, Lift .555/.555

Duration 282/282, Lift .495/.495

Duration 270/270, Lift .468/.468


What does all that translate into? The 270/270 spec has an operating range of 1800 -5800. Seems more in alignment with street cruising?

Should I wait until I find out about potential for overbore?

Also, plan is to run the D4B intake and a Holley 4160...600cfm
You didn't list over lap, but number 3 is the tamest of the ones listed. Will need a lot of converter stall for the first one.
 
You didn't list over lap, but number 3 is the tamest of the ones listed. Will need a lot of converter stall for the first one.

Thanks...

Yes, as I read... the 555 is way outside my application

Looking at some Isky options... something closer to the Commando cam
 
The zebra dart's 318 was a blast off the line. Had a pretty "mild" cam in it.
Doing some digging the engine and car came from Skinner & Co. with (0.420"/0.436", 219degrees @ 0.050"). I drove the car in '06 so it still had that cam.
He discusses adding headers and then high flow heads before changing cams
Granted a 318 isn't a 273 but just trying to provide some perspective. For street and autocross it was a good setup. And it fit the rules for a the vintage race class Skinner set it up for on the west coast.

Side note: I'm convinced that the bearing clearances, oil pump, and temperatures are too cold for 20W-50, but Dave is not (yet). 50 has some advantages for road racing but the bearings have to be built for that, etc.
 
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OK... so am I an idiot for ...

OK.. lemme rephrase. I know I'm an idiot. I have historical records of that.

Am I killing myself unnecessarily trying to resurrect this 1965 273. I feel like Carol Marrel is going to open door number 3 and I've won some pile of crap.
 
OK... so am I an idiot for ...

OK.. lemme rephrase. I know I'm an idiot. I have historical records of that.

Am I killing myself unnecessarily trying to resurrect this 1965 273. I feel like Carol Marrel is going to open door number 3 and I've won some pile of crap.
Sorry for the disagree but know way in hell are you an idiot Chris.
 
trying to resurrect this 1965 273
No idea if its a good idea or not. I haven't followed the saga.

Resurect to me is fixing what's wrong and reincarnating as something close to a factory 2 bbl or 4 bbl.
The 273 guys like TMM can probably guide you on the best part combos.
Finding a cam that might provide more torque or carry higher up in the rpm is reasonable too.

I just saw the cams you posted and and to me those are really high lift, and thats more than a resurect. That's a major hot rodding or racing project. In general the more lift, the high spring pressures and shorter life, but its the risk/price for trying for maximum power.

A lot more experienced and knowledgable people than me when it comes to building more performance into engines. I've just been sucked in enough to have learned a little.
 
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