Great day for porting

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pittsburghracer

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Till a storm blew in and knocked out the power. Well I did get both heads tubed and the pinch opened up on one head. Customer isn’t in a big big hurry but with no racing this weekend I should be able to hit the hard.




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So I am assuming since you tubed the pushrod holes, that you ported into the original ones. Is that correct? I'm just curious, how much do you suppose that widens the port? I know it's a lot, but I'm curious about a number.
 
So I am assuming since you tubed the pushrod holes, that you ported into the original ones. Is that correct? I'm just curious, how much do you suppose that widens the port? I know it's a lot, but I'm curious about a number.


I’ll try to let you know tomorrow but I’m thinking at least .100 plus what you gain pushing the common wall over and straightening it.
 
I’ll try to let you know tomorrow but I’m thinking at least .100 plus what you gain pushing the common wall over and straightening it.
Cool. Thanks. I've always wondered how much porting one that far added.
 
I used to put a piece of drill rod into intake pushrod hole, then set it up in a mill, and run my cutter until the cutting edge was 0.100 or 0.125 from the drill rod edge. Then mill the inside wall of the port. Then you just blend it in to the port matching line on the near side, and blend the far side into the bowl throat. I'd also semi permanently install studs( w/blue loctite sealer) into the valve cover mounting holes over the intake ports because when you gasket match you might break into the threaded holes. In which case, no big deal, you're just grinding on the studs a little.
I used to call them w-1's, hahaha
 
I’ll try to let you know tomorrow but I’m thinking at least .100 plus what you gain pushing the common wall over and straightening it.


Gonna be awhile guys. Power isn’t supposed to be back on till 11pm tomorrow night. We got hammered with a storm here.
 
They are, sorry I didn't realize this was the SB forum. They are eddy RPM heads.

Regardless they are tubed and the flow numbers are impressive as a partial result
 
I know it's not a SB head, but IIRC it was something like 292cfm OOTB and 345 after the porting and valve diameter change.


If they were flowing 292 out of the box this gentleman’s flowbench needs calibration. They don’t flow that well out of the box. This is why I check calibration on every head I flow.
 
The 292 number I looked up for OOTB BB perf RPM heads, for the sake of a reference. The only number from his bench I paid attention to and locked in my head was the 345
 
I know it's not a SB head, but IIRC it was something like 292cfm OOTB and 345 after the porting and valve diameter change.

Yeah that's the BIG difference in what I observe-the starting point. An OOTB Eddy RPM--Goes 257-263 cfm on my bench untouched--Heck a OOTB Victor does 278-285 as a starting point. I've got some SideWinders here ported by a BIG name guru here that I was asked to flow that peak at a whopping 287cfm--sold as flowing 318+cfm! The customer was pissed as he thought they were stock--I assured the customer that OOTB they would be in the 257-263 cfm range--He felt a little better but not much. J.Rob
 
I've got some SideWinders here ported by a BIG name guru here that I was asked to flow that peak at a whopping 287cfm--sold as flowing 318+cfm!

One thing people should keep in mind regarding flow bench results where the same head is tested at multiple facilities.
If bench A is 300, bench B is 315, bench C is 320........ regardless of the different numbers........the head itself didn’t change.

In other words, if the heads are on an engine that’s being dyno tested, and you tape the flow sheet from bench A, then B, then C on the engine....... it won’t have any affect on engine output....... or the dyno sheet.

Same for the drag strip.
The car won’t go quicker with the bench C flow sheet in the glove box instead of the one from bench A.

I just expect that the numbers from different benches will differ.
(No, it “shouldn’t” be that way, but that seems to be the reality)

If RAMM’s customer was happy with the performance of his heads as he was thinking of those 318cfm ports........ the good news is, the performance will be exactly the same, even though he now also has a piece of paper that says 287cfm.
 
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One thing people should keep in mind regarding flow bench results where the same head is tested at multiple facilities.
If bench A is 300, bench B is 315, bench C is 320........ regardless of the different numbers........the head itself didn’t change.

In other words, if the heads are on an engine that’s being dyno tested, and you tape the flow sheet from bench A, then B, then C on the engine....... it won’t have any affect on engine output....... or the dyno sheet.

Same for the drag strip.
The car won’t go quicker with the bench C flow sheet in the glove box instead of the one from bench A.

I just expect that the numbers from different benches will differ.
(No, it “shouldn’t” be that way, but that seems to be the reality)

If RAMM’s customer was happy with the performance of his heads as he was thinking of those 318cfm ports........ the good news is, the performance will be exactly the same, even though he now also has a piece of paper that says 287cfm.



yes but if you are looking to get a set of heads ported are you going to take them to the guy that gets an honest accurate 318cfm or the guy promoting 342cfm. That’s why I like to see before and after numbers from the same bench because that 342 guy started at a way higher number. I’ve done both hand ported and cnc ported heads and have witnessed the disappointment when they see the truth.
 
One thing people should keep in mind regarding flow bench results where the same head is tested at multiple facilities.
If bench A is 300, bench B is 315, bench C is 320........ regardless of the different numbers........the head itself didn’t change.

In other words, if the heads are on an engine that’s being dyno tested, and you tape the flow sheet from bench A, then B, then C on the engine....... it won’t have any affect on engine output....... or the dyno sheet.

Same for the drag strip.
The car won’t go quicker with the bench C flow sheet in the glove box instead of the one from bench A.

I just expect that the numbers from different benches will differ.
(No, it “shouldn’t” be that way, but that seems to be the reality)

If RAMM’s customer was happy with the performance of his heads as he was thinking of those 318cfm ports........ the good news is, the performance will be exactly the same, even though he now also has a piece of paper that says 287cfm.

I don't know if he was happy or not , thankfully this was a forced induction deal that likely made the heads perform, flow results be damned. J.Rob
 
I’m pretty sure I know who the owner is...... and where the heads were done.
And, if I’m right about that....... then I’m pretty sure I know why he had you flow one.
 
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