505 stroker fresh off the dyno - Power seems low? Thoughs?

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Minnesota Muscle said:
Pretty sure I'm answering every question I can at this hour. I've already answered your questions. Yes it was degrees with a wheel, stop and indicator.
The Dyno operator never measured the cranking pressure.
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So, are you not capable? If you want good info, we need good info. Cranking compression numbers are crucial to the questions you've asked.

...and no, this is the FIRST TIME you've mentioned using the tools I asked about to degree the camshaft. All too often we see people say the camshaft is degreed when all they did was line the dots up. Without a detailed explanation, we have no idea. I have eight cats and they knocked my crystal ball off the dining room table and broke it some time ago and I cannot read minds.
 
Here are the only other photos I have, slightly different angles of it helps.

IMG_20210609_212452~2.jpg


IMG_20210609_212442.jpg
 
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Rmoore said:
No big deal ! just trying to help you like you ask us to ! looking at those pictures of your pistons, looks like you may have 27cc pistons instead of the 17cc dish your suppose to have ! really hard to be for sure looking at a picture though
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I have a bore scope, I'll send down in tomorrow and get some detailed photos of the dish and it's contours.
 
At this point, it may be a little irrelevant what pistons you've got since you don't know what the deck height is. Just get some cranking compression numbers and go form there.
 
I used stock deck height since you said "just cleaned up". Used the nominal .038" head gasket. I got 9.6:1 static and 7.5:1 dynamic using the United Engine calculator. Lots of unknown variables still though.
 
They don't even have the 5060 pistons listed on their site that I see. I BET you got the 24cc pistons substituted.
 
RustyRatRod said:
Then therein lies the issue. He's built a 505. That's a 4.15 stroke engine. That 5060 is for a 4.250 stroke and has a MUCH shorter compression distance. He probably has 7:1 compression with his combination.
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In post #1, he said he had the 512/440 kit.
 
RustyRatRod said:
Then therein lies the issue. He's built a 505. That's a 4.15 stroke engine. That 5060 is for a 4.250 stroke and has a MUCH shorter compression distance. He probably has 7:1 compression with his combination.
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4.350 bore 4.25 stroke comes up 505. The 5060 is correct
 
mopowers said:
These pistons aren't at TDC, are they??? :poke::rofl: Sorry - couldn't help it.

View attachment 1715789053
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I certainly hope not.

See.....that's the WHOLE problem with people just writing checks (no offense). Since you don't actually see and inspect the parts yourself you're at someone else's mercy. He could have anything and there's no way for us to know. I would say at this point, everything needs to be verified. That's a 600 plus HP combo he's got. Something is severely wrong.
 
Rmoore said:
4.350 bore 4.25 stroke comes up 505. The 5060 is correct
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Ok....I was looking at the 4.15 stroke stuff.

Plus, when you go on the 440 Source site, the 5060 piston does not come up from the menu. Where are you finding the link?
 
If they sent the wrong piston, I've got to think 440 source would have noticed that they have eight extra 17cc pistons and are missing eight 27cc pistons. Then again....

Guess we'll find out Monday when I call.
 
Either way, in the end, even if they say yes we sent the wrong ones. The whole thing comes apart and starts over as I'd have to send the rods back to get balanced again. Question is, it worth it...
 
Minnesota Muscle said:
Either way, in the end, even if they say yes we sent the wrong ones. The whole thing comes apart and starts over as I'd have to send the rods back to get balanced again. Question is, it worth it...
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Put a blower on it?

Seriously, run that compression test and that will tell the story.
 
I think the HP is about right for the SFT cam you used. It is not that big for a 500+ in stroker, with the consequent power you got. You might be able to tease out a few more HP by experimenting with the cam's ICL [ I would retard it 4* to start with ], timing, carb spacer.
 
Further thoughts.
I doubt the pistons are down in the bore because would likely need a LOT more than 30* of timing for best HP.
Your lash can be tightened up considerably. You would normally allow about 0.003/4" for expansion with alum heads. But the TF heads are tall & because they use pedestals to mount the rocker shafts, you need to allow more [ ~0.005-6"] than you would for a rocker stud head like a Chebby. I would lash at 0.006/0.008" cold.
Don't have the TF flow #s in front of me, but seem to recall about 300 cfm @ 600 lift.
For a NA engine, a rough guide to expected HP, you double the flow number; this assumes the rest of the parts are sized to work together. So you are not too far off.
 
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