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Discussion Starter · #161 ·
bullheimer said:
just to re-cap a bit. for this to matter in a head, you need to have quench, and the quench area is the flat part of the head where the piston will squish the mixture. this means that in my heads pictured here, where there is absolutely NO flat area, that using grooves would be a total waste of time right?

i didnt notice before, but there is no flat area at all to speak of. maybe a half inch at best, so i guess i'll just wait till i build a different engine.
With the squish area being so small, the benefits will be less pronounced.
 

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Discussion Starter · #162 ·
1ownerT said:
This thread started with a civil exchange of ideas that shortly thereafter went out the window.
Someone explain why this pissing match has not been dumped. Eleven pages of the same crap, there are three sides, those that swear by it, those that would give it a chance, and those that will not believe in it unless there is scientific proof that it works. Apparently no one is willing to put up the cash to prove or disprove the theory. I have seen less get dumped quicker. How many more pages does it need to go on?
Eventually I hope to be able to discuss this with people that have tried it.
 

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Give me four months and I'll have my vortec 355 on a dyno with before and after numbers, including BSFC, EGT, jet sizes I use, A/F ratios, and ignition detonation limits with 87 octane and 93 octane.
 

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curtis73 said:
Give me four months and I'll have my vortec 355 on a dyno with before and after numbers, including BSFC, EGT, jet sizes I use, A/F ratios, and ignition detonation limits with 87 octane and 93 octane.

I can't wait that long!!! :D :D

Is there any way to test lean misfire limits on the dyno?? I guess it would depend on the dyno.
 

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Discussion Starter · #165 · (Edited)
hotrodf1 said:
I can't wait that long!!! :D :D

Is there any way to test lean misfire limits on the dyno?? I guess it would depend on the dyno.
One way to test lean burn mis-fire limits is to monitor HC emissions. When the engine begins to mis-fire HC emissions will go up.
 

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johnsongrass1 said:
That is exactly what no one on this forum can do and why I refuse to accept that it might work. I trust my builder, he put's out 1000 engines a year in drag, circle and marine applications for 30 years. When I asked him about it...his reply was, "never heard of it".

Just think of the engine damage that could of been thrwarted with this sooooo easy grooves. I can't believe no one is using this. IT's the new age of engine building.(read sarcasm here)

The mod is so cheap and quickly done, that one should be able to afford the dyno time. Some one did sometime, and it don't work.

You guys don't have a clue of who I am, where I came from, nor my background. (and it doesn't matter either) I promise you, there are tricks that have been done on the west coast and in the northeast for TWENTY YEARS that are now just making it to the rumor mill in middle America. (you think NASCAR has the corner on all tech?)

Here's another food for thought along this same "combustion efficiency" line.

Let me be redundant in stating that this mod is NOT to make more top end horsepower but to increase detonation resistance at lower rpms and high BMEPs. A dyno might not show any hp increase, but below 3500 rpm the detonation might be eliminated.

Have you ever noticed the combustion burn on high dome pistons especially? Often a heavy carbon deposit forms a line across a dome. Those grooved pistons from EMC shown in this thread have that carbon ridge. And I conclude that engine cannot have many hours of running on it.... mmmmmm?

SOME engine builders recognize that the sharp edge of domes need to be radiused and massaged to an "egg like shape" to assist in the burn propagation across the chamber. OTHER professional builders in racing circles and even in the Engine Masters Competition just put the out of the box piston domes in their engines. Sometimes you'll see them notch out around the spark plug a little more. Just look at all the pictures for several years. And yet it is a proven fact that full dome contouring helps....

Engineer David Vizard also comments that domes taller than .120 in a SBC actually offset the compression power gain because tall domes hinder the flame front so drastically. He has written that he has seen 100 hp lost due to tall domes.

Builders modify almost every other engine component, carbs, spacers, intake manifold runners, port/gasket match, head porting, chamber shapes, valves, valve back cuts, valve seat angles, and then use out of the box piston dome
contours. mmmmmmmm? Some BIG NAMES don't, a few do.

By the way, grooving the piston quench circumvents the shallow valve edge/head problem and allows alternate groove placement. If you think that the head will crack, cut the .080 deep groove into the piston. simple. This really isn't "rocket science" people.

As for builders' atitudes. I have met several BIG NAME BUILDERS that have told me "I have been in business for "XXX" years and that is the way I have always done it"...... stuck in the past. :(

I even know of one BIG NAME builder that in '98 told me eyeball to eyeball that he hones cylinder walls with ONE type finish regardless of which rings will be used because---- "I have been doing it for 22 years"...... :nono: (He also does not contour domes)

FWIW Just thinking. :welcome:
 

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xntrik said:
As for builders' atitudes. I have met several BIG NAME BUILDERS that have told me "I have been in business for "XXX" years and that is the way I have always done it"...... stuck in the past. :(

I even know of one BIG NAME builder that in '98 told me eyeball to eyeball that he hones cylinder walls with ONE type finish regardless of which rings will be used because---- "I have been doing it for 22 years"...... :nono: (He also does not contour domes)

FWIW Just thinking. :welcome:
Your whole post was great but not as great as what I have in the quote section. :thumbup: :D :thumbup: :D :cool: That was pretty good stuff and you are right 110%. I have done it this way for 40 yearzzzzzzzz and I am not about to change now bla bla bla. Stuck in the mud ole timers.
 

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curtis73 said:
......... Manufacturers are so far behind what could be because the bean counters look at it the same way you guys are. The engineers say, "this is good new technology" and the bean counters say, "we've been just fine for 100 years without them, and new technology costs money."

.........If you don't like it, move over and let us discuss the tech part. You can stand back and laugh if you want, but I feel like we're spending so much time discussing the yes's and no's that we're not talking about tech anymore.

.

amen amen amen :thumbup: Preach on Brother.

If it weren't for the Japs and the FEDS smog mandates we's still be driving those horrible mid 70s technological marvels made by Chevy, Ford, and everybody else (180 hp 455s that got 12 mpg on the interstate). :rolleyes: :rolleyes: :rolleyes:
 

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Why did that engine maters engine piston have a hole in it right wihere the crooves came to a point?

The speedtalk thread has a very nice blown up pic of it?
 

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I have been commenting :welcome: as I progressively read this thread.

Please allow me state ONE MORE TIME......

Back when I was a teen, Don Metzgar in Chicago was grooving cylinder heads in '62... I saw them, I raced against them.

I never had any on my engines.

I had the track records at 5 different "circle" tracks and overall season points championships at 4 of them... for multiple years. My engines had several mods that consensus said "Can NOT work" :D :D . But I carried the checkered flag over 500 times from 1960- 65 and won 92.2 % of all the races I ever drove.

Engines are necessary but it also helped to be the best driver on the track. :thumbup:

For those of you thinking.... let me comment...

1) Racing didn't pay squat 40 years ago.
2) Engine/car building paid even less.
3) Then there was a war, a recession, marriage, children. Life happened.
4) I went to work in aluminmum tubing.... I regret that I never stayed with my passion and dreams 100 %, :D .... but somebody had to fly those darn airplanes.
 

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Rick WI said:
Why did that engine maters engine piston have a hole in it right wihere the crooves came to a point?

The speedtalk thread has a very nice blown up pic of it?

http://speedtalk.com/forum/viewtopic.php?t=4145&postdays=0&postorder=asc&start=15

Thanks for the heads up.

I see no "hole". I see "poorly controlled" milling and grooves that appear to be much wider and inconsistent than the grooves that Singh and AB are advocating. These grooves converge at the spark plug relief notch.

I can't imagine that if there were a "hole" through the piston that the engine builder would allow a picture of it to appear without acknowledgement.

I still think the sharp edged domes need contoured.
 

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Discussion Starter · #175 ·
Here are a few opinions on the BES engine masters entry. Looking at the pictures it is appears the modifications were done with out recommendations from Somender Singh. Everything I have read from Singh indicates cylinder head modifications, he has reasons for this. In addition squish clearance recommendations were not followed.

The engine builder reported a mistake that was made in the final compression ratio for the fuel in use. The poor valve angle of the Brodix heads required a dome piston to fill the large chamber; this in itself is not desirable for detonation resistance and superior flame speed. The burn patterns indicated incomplete combustion.

“The compression ratio was pretty stout at 12.5:1, and that may have been pushing it” Bischoff disclosed, “It may have been a mistake.”

It appears the engine builder attempted to compensate for detonation limitations with the tune up, adding fuel and retarding ignition timing on a detonation limited entry. The quote below indicated that the builder did not fully test the modifications before competition.

“The fire slots on the pistons were something Tony had little previous experience with, at least that he would admit to”
 

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Rick WI said:
Half way down that page that piston was clearly eating itself up.

Thank you for your ovservational input.

The two pictures that just posted, and looking at the original web postings= By looking at the milling and the carbon tracking they are obviously two different pistons.

In the upper picture I see the "lower" groove as being poorly milled, like the piston or mill slipped and made the groove wider and deeper toward the convergence. See the milling overlap?

In the second picture I see between that corresponding groove and the dome what appears to be a dimple that looks like someone with a hand held ball mill made an uh-oh. There also appears to be an irregularity in the edge of the high dome that might have been made by a "chuck" hitting the edge of the dome.

Knowing that many flat pistons have been milled reducing their head thickness to alter compression height, others have had their domes lowered, many have had gross amounts taken out for hand cut valve reliefs... I feel that a minor spot of that nature would not necessarily jepordize the integrity of the piston head. I speculate that the EMC builder concurred.

Based on these pictures, without personally examining the pistons, :mwink: I cannot state that "clearly eating itself up" is a term that could be used to describe this situation.

I also will comment that the recommended grooving is with a .063 ball mill with a depth of .080, then filed to .120 max surface width. It looks to me that the pistons in question have been milled with a ball mill of three times that diameter, and inconsistently done, one to the other.

JMO thanks,
x
 

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And what would a piston "eating itself up" have to do with how grooves can't work?

C'mon, its like we're in a character debate and two candidates are mudslinging. I don't care if my candidate used to bang hookers, if he does well in the office, I vote for him.

I don't care if a 12.5:1 engine ate pistons on pump gas, if the grooves work, they work.
 

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A few years ago a company called Hi-Tech (Nusource) developed a piston for the SBC that supposedly promoted swirl, increasing horsepower, etc. It didn't catch on.

I wonder if a groove in the piston as opposed to a groove in the head may have the same effect, similar to those in the pictures posted.

I rember when some Nascar teams were dimpling the intake side of the combustion chamber. I wonder if any are doing that now.

I am not "for" or "against" the head grooving process. I just haven't seen any evidence proving that it makes a big difference. For something that has been around as long as it has, it hasn't set the world on fire. I think there may be something to it, but there are many variables that may mitigate the effect, such as deck clearance, piston dishing, basic combustion chamber design, etc.
 

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Discussion Starter · #179 ·
Hi kdrolt,
i haven't heard from you in a while. I'd like to hear your opinion on this now that some time has passed.

I should be finishing two set of heads this week, I'll post pictures later.

Dart 345 BBC heads for a high compression bracket car

and Edelbrock SBF heads for a street strip pickup truck with a Eaton blower
 

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For something that has been around as long as it has, it hasn't set the world on fire.
True, but in that context, EFI was around for about 15 years before it "caught on". Caddy, BMW, Jag, and some Japanese companies had EFI examples as early as 1974 and it was dismissed as complicated and that it wouldn't ever catch on.
 
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