BBC output overview - chapter 2

General engine tech -- Drag Racing to Circle Track

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Erland Cox
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Re: BBC output overview - chapter 2

Post by Erland Cox » Tue Nov 27, 2018 4:51 pm

David, I must admit, you are an expert at never answering questions.
But I guess it is just the way it is.

Erland

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Re: BBC output overview - chapter 2

Post by RevTheory » Tue Nov 27, 2018 5:27 pm

He's not answering his phone either. It's called being busy.

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Re: BBC output overview - chapter 2

Post by hoffman900 » Tue Nov 27, 2018 5:29 pm

RevTheory wrote:
Tue Nov 27, 2018 5:27 pm
He's not answering his phone either. It's called being busy.
I think Erland’s comment went over your head ;)
-Bob

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Re: BBC output overview - chapter 2

Post by RevTheory » Tue Nov 27, 2018 5:45 pm

Erland called him out for not answering him and David hasn't responded to me either so I suggested he's just busy; at least let's hope that's all it is. I wouldn't be surprised if I missed something though.

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Re: BBC output overview - chapter 2

Post by digger » Tue Nov 27, 2018 5:53 pm

RevTheory wrote:
Tue Nov 27, 2018 5:45 pm
Erland called him out for not answering him and David hasn't responded to me either so I suggested he's just busy; at least let's hope that's all it is. I wouldn't be surprised if I missed something though.
I think the point was that he responded to Erlands question but didn't answer it

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Re: BBC output overview - chapter 2

Post by David Vizard » Fri Nov 30, 2018 6:57 pm

Erland Cox wrote:
Mon Nov 26, 2018 4:52 pm
Taking away quench area should loose power.
Is it a low octane pump gas thing to slow down combustion velocity with less quench?
Trying to get slower pressure rise to control detonation?
I have only seen smog head BBC oval port heads look like that and never an N/A race head.

Erland
Erland,
Are these the questions you are referring too? If so my apologies as I took them for statements not questions. Let me know.
DV
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Re: BBC output overview - chapter 2

Post by David Vizard » Fri Nov 30, 2018 7:04 pm

Erland Cox wrote:
Tue Nov 27, 2018 4:51 pm
David, I must admit, you are an expert at never answering questions.
But I guess it is just the way it is.

Erland
Erland,
Now come on - let's play the game here.
So often your questions require a much longer answer than most. So as the rest of the ST folk get a balanced view here would you like to tell them just how often I have asked you to call so I can answer your questions in depth.

Since you ask such good thought provoking questions I have all the time to answer them for you. Not many folk get that from me. You are one of a very short list!!

DV
David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.

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Re: BBC output overview - chapter 2

Post by digger » Fri Nov 30, 2018 7:06 pm

Erland Cox wrote:
Mon Nov 26, 2018 6:04 pm
David Vizard wrote:
Mon Nov 26, 2018 4:17 pm
Erland Cox wrote:
Mon Nov 26, 2018 2:01 pm
Why do you cut the quench area so much on the exhaust side?

Erland
Because that design makes more power than when it is not cut away. On a 540 with a 10.5/1 CR it's worth about 18 hp on a nominally 750 HP build.
It also makes the chamber less prone to detonation when using pump gas.
DV
Just out of curiosity, have you tested this type of head on a 540 with and without that chamber mod and no other modifications?
No flack just a scientific question which I hope I will get a scientific answer for.

Erland
This is the question

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Re: BBC output overview - chapter 2

Post by David Vizard » Fri Nov 30, 2018 7:20 pm

Erland Cox wrote:
Mon Nov 26, 2018 6:31 pm
swampbuggy wrote:
Mon Nov 26, 2018 6:22 pm
Erland.....David has already answered your question just barely above your question, :-k Mark H.

No, he only said that the mod gave 18 hp so I wanted to hear more about the 540 test,
The head he is porting looks like it has never been run before the porting started.


Erland
Erland,
You have me dodging through all these posts at a time I am trying to meet PRI deadlines.

All you need to know here is that this mod, on a 24 degree BBC, whether it is street or race, produces an increase in output with no down side as far down as the dyno will pull (usually 2750 - 3000)

If you can be patient and wait until I return from PRI I will post the results of this mod as applied to a set of heads done by a prominent Pro-stock porter with many championships to his credit. These tests were part of my 572 update program done with GM's blessing.

DV
David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.

Erland Cox
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Re: BBC output overview - chapter 2

Post by Erland Cox » Sun Dec 02, 2018 1:46 pm

That will be interesting.
My son is coming to PRI with Michael Malmgren pro stock racing.
I think he is going to spend a lot of time at EMU injection as that is his biggest interest right now.
With 5 big mean dogs I don´t get to travel so much anymore.
No one else wants to take care of them.
But I have lots of things to do at home, often to much.
I am not much of a telephone guy. I much rather meet directly or write.
Especially in a foreign language, sometimes it is difficult to find the words.
I appreciate your offer though.

Erland

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Re: BBC output overview - chapter 2

Post by David Vizard » Sun Dec 02, 2018 2:10 pm

Erland Cox wrote:
Sun Dec 02, 2018 1:46 pm
That will be interesting.
My son is coming to PRI with Michael Malmgren pro stock racing.
I think he is going to spend a lot of time at EMU injection as that is his biggest interest right now.
With 5 big mean dogs I don´t get to travel so much anymore.
No one else wants to take care of them.
But I have lots of things to do at home, often to much.
I am not much of a telephone guy. I much rather meet directly or write.
Especially in a foreign language, sometimes it is difficult to find the words.
I appreciate your offer though.

Erland
Erland,
I will be doing two seminars at PRI one for Scat and one for Calhoun Custom Porting.
The Scat one is on the 5th at 4:00 pm in room 241 and the 7th at 4:00 pm room 236. for Calhoun

I will also be at Calhoun Custom Porting booth, Green Hall # 7216. I'd be happy to give your son and his friend some personal time to answer questions they may have.

Meanwhile if you PM me with your Phone # I will call you as I have some questions I think you will have answers to.
Thanks
DV
David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.

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Re: BBC output overview - chapter 2

Post by David Vizard » Sun Dec 09, 2018 5:56 pm

Just finished up the tunnel ram intake for the 'weird' port Dart heads I showed way back in this thread.

It got a little thin in places but nothing that could not be remedied. Flow bench check showed good.
DV
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David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.

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