Intro to a port job

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Once the valve job is complete , all angles are there, they will change/go up. This is off only a 45 seat cut. If it was a complete 3 angle the low lift would be higher and typically all numbers.
.100 65
.200 125.8
.300 189
.400 240
.500 260
.600 247
The dogleg is always greedy. Air speed a plenty.
 
Okay..paid the machine shop a visit to square up , will be posting the #s int/exh. In the meantime some crank grinding action going on over there.


 
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I have to acknowledge the guy I know that does machine work and grinds cranks at his dad’s place. Pic is from the 1985 direct connection catalogue.
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RustyRatRod said:
Old school. I'm diggin it.
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Is that process indexing? I noticed it was grinding mostly one side. I didn't think about how the crankshafts can be "off" in the index department until you mentioned it maybe in another post.
 
Bodyperson said:
Is that process indexing? I noticed it was grinding mostly one side. I didn't think about how the crankshafts can be "off" in the index department until you mentioned it maybe in another post.
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I saw that as well. I can only assume one of two things. Either he was straightening up an egg shaped journal, or perhaps he was offset grinding. I'm assuming the first since offset grinding would have been removing more material. Rest assured, if @MOPAROFFICIAL uses him, he knows what's up.
 
Bodyperson said:
Is that process indexing? I noticed it was grinding mostly one side. I didn't think about how the crankshafts can be "off" in the index department until you mentioned it maybe in another post.
Click to expand...


Indexing the crank means the grinder makes all the stroke lengths the exact same and that looks like what he's doing.

The only way to grind the rod throws is to index crank so it spins the Rod throw on its axis.
 
And it also means that the crankpins are all trued to 90 degrees of one another after the first throw is indexed to the snout key for true TDC on the balancer.
 
And I'd like to point out that sometimes you can't get it fully indexed with just a .010 under grind. Sometimes you just live with how close it is and correct the TDC timing mark on the cover.
 
Okay, sorry for the delay. I've popped 2 intake valves 'cyl 2 & 4 or 3 & 5' which ever bank they end up on ..and here are the numbers.
Cylinder 2. & Cylinder 4.
.100--65--------64
.200--130------129
.300--188.7---188
.400--238------237
.500--261------261
.530--264------262

Close numbers, port to port. Consistency is winning. So the valve job did 3 things, helped .200 & .500 lift flow as much as 5 cfm, increased air speed 'had to turn the volume up on the common/straight side on port on the right...and yet, showed there is still some room. As for comparing, I'll have all the port numbers up when this is all said and done so you can get the big picture. EDIT-The numbers on the left are of the port pictured in post #142 a few up from this in case you wondered what that looks like. Here are some other pics.

Side note
These are the valves I recommend using.
2.02

Engine Pro 01-2003-100 SBC Chevy Stainless Intake Valve 2.02 X 5.01 X 11/32 Stem | eBay

1.60

SBC 1.6" Dia 5.010" Nitro Black Perf Exh Valves Small Block Chevy 01-3001+100 | eBay

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20200207_134650.jpg


20200207_134657.jpg


20200207_134811.jpg
 
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