Matching chambers to the bores

[wyrmrider]

The quench side is the long side not the short side but I see your point what about the ss on the right side of the exhaust?

[joespanova]

Thanks for the great pics and flow ball suggestion AND the link.............thanks ALL for the help.
For the record my heads are old school pro. ported 23 dg. Brodix Tk 1s.

[blackford]

I did this years ago on the 331 in my Mustang. It was bored over by .030. My thinking was that the exposed edge of about 1/32 to 1/16 could be disruptive especially for exhaust flow. Does Vizard recommend doing this?

[user-612937456]

I did this years ago on the 331 in my Mustang. It was bored over by .030. My thinking was that the exposed edge of about 1/32 to 1/16 could be disruptive especially for exhaust flow. Does Vizard recommend doing this?

Not sure if I follow you but if you are talking about the seat there is especially benifit of the seat and back cut on the valve at low lift under .250

[mag2555]

I was just making note that some people attack that side too, and if you do not have a flow bench to track changes you can get yourself on that smelly creek with no paddle !

[Newold1]

I have worked with a lot of cylinder heads,intake and exhaust systems that involved a great deal of both trial and error and specific air flow and velocity experimentation and measurement. I can really attest to a single thought that I have come to put a lot of stock in. Air flow as it relates to added performance in design and especially modification of engines is a bit of "A BLACK ART".

I now always keep in my mind a couple of things I always seem to be exposed to:

1. If it was easy, almost everybody could do it! I have now learned that it is not easy!!

2. When it "LOOKS" good and seems like the right thing to do, it probably isn't!

Listen and learn from the experts! They've already been thru the try, fail and succeed time and expense you really don't need to repeat! Try to not experiment on to many parts you had to dig fairly deep to pay for!

Always remember - LISTEN, LEARN, DO and SUCCEED !

[Carnut1]

I have worked with a lot of cylinder heads,intake and exhaust systems that involved a great deal of both trial and error and specific air flow and velocity experimentation and measurement. I can really attest to a single thought that I have come to put a lot of stock in. Air flow as it relates to added performance in design and especially modification of engines is a bit of "A BLACK ART".

I now always keep in my mind a couple of things I always seem to be exposed to:

1. If it was easy, almost everybody could do it! I have now learned that it is not easy!!

2. When it "LOOKS" good and seems like the right thing to do, it probably isn't!

Listen and learn from the experts! They've already been thru the try, fail and succeed time and expense you really don't need to repeat! Try to not experiment on to many parts you had to dig fairly deep to pay for!

Always remember - LISTEN, LEARN, DO and SUCCEED !

I would like to add that some professionals give advice that may not be helpful. The idea is if you can't speed up then slow down the field mentality. Overall I think Speedtalk is pretty good this way because advice of this type would be called out by some expert talent here. Jmo. Thanks, Charlie

[joespanova]

...........WHICH IS THE REASON I MAY JUST GIVE THEM TO A PORTER....after I scribe the bore lines.............

[mag2555]

Let me offer a example of a very common occurrence that can take place when no flow bench is at hand to check results.

In this example we have a head that flows whatever Intake cfm amount at max Cam valve lift.

By means of the flow test we find that at this Intake valve lift that will be applyed by the Cam that the the flow bench is showing signs that with the air mass we are passing through it that pumping action is starting to take place.

This is the start of air mass sheer, port tumble , or two other names you can apply to this act, and the flow bench is showing the air flow number jumping up and down.

The main thing to understand is that when a Intake port starts to pump its reacting to a level of air mass moving through it that's on the edge of its control. If we then where to do any port mod, valve seat mod , or even back cut a valve that made it possible to move more air through the port at lifts less then what we are running, this has then increase the total mass of air moving through the port with the result that now the port is in full port sheer and our peak air flow numbers that we once had have taken a dive to the tune of 10 to 20 CFM!!!!

When you concider that even just a 10 cfm loss per cylinder is 5 hp , now your motors down 40 hp from what it could have had!

[randy331]

When you concider that even just a 10 cfm loss per cylinder is 5 hp , now your motors down 40 hp from what it could have had!

Your post assumes more cfm always results in more power.

When you see a head with 20 more cfm make 40 less HP you start realizing the limits of a flow bench.

Randy

[joespanova]

OK' You guys are scarin' me now..........I'm not touchin' the damn things........
Larry Meaux , I need you bro........

[randy331]

OK' You guys are scarin' me now..........I'm not touchin' the damn things........
Larry Meaux , I need you bro........

I "could"? be interested in looking at them if you want.

Randy

[Carnut1]

[quote="randy331"][quote="mag2555"]
When you concider that even just a 10 cfm loss per cylinder is 5 hp , now your motors down 40 hp from what it could have had![/quote)

Your post assumes more cfm always results in more power.

When you see a head with 20 more cfm make 40 less HP you start realizing the limits of a flow bench.

Randy[/quote)


This seems totally counter intuitive. If you improve the cfm and power is reduced the only reason I can think of is you have breached the detonation barrier for that combination. I would love to know more. Thanks, Charlie

[user-23911]

What about the gasket?

[MadBill]

When you concider that even just a 10 cfm loss per cylinder is 5 hp , now your motors down 40 hp from what it could have had![/quote)

Your post assumes more cfm always results in more power.

When you see a head with 20 more cfm make 40 less HP you start realizing the limits of a flow bench.

Randy[/quote)


This seems totally counter intuitive. If you improve the cfm and power is reduced the only reason I can think of is you have breached the detonation barrier for that combination. I would love to know more. Thanks, Charlie

It depends on how the flow is raised. Carving a port out to large by huge will increase the flow but kill port velocity and power.