Combustion Flame Speed

Rod Rocks · Post by **Rod Rocks** » Fri Aug 04, 2006 1:34 pm

Darin Morgan wrote: I have .160 thousands of flat on the intake side of the chamber. It does not seem like a lot but if you take it out, its disastrous to say the least. The engine will drop 8ft/lbs and it will kill the fuel flow 10lbs/hr. I will see if I cant get some pictures so I can explain it better.

Thanks, pictures would be great, If not I'll understand. I'm having problems visualizing the .160 flat on the intake side.

Unkl Ian · Post by **Unkl Ian** » Fri Aug 04, 2006 3:07 pm

My GUESS based on Darin's description:
Imagine the parimeter of the chamber scribed to match
a 4.500" dia cylinder,then the chamber beside the intake valve
opened up to that line.

Just like in all the old magazines.

Then bolt the head on a 4.820 bore block,and shape the piston to match.
You would end up with a .160" quench area beside the intake valve.

beth · Post by **beth** » Fri Aug 04, 2006 3:15 pm

Yes, and combined with a steeper valve and port angle plus having the valve at the bore centerline valve shrouding is not as much of a problem.

Darin Morgan · Post by **Darin Morgan** » Fri Aug 04, 2006 4:46 pm

Unkl Ian wrote:My GUESS based on Darin's description:
Imagine the parimeter of the chamber scribed to match
a 4.500" dia cylinder,then the chamber beside the intake valve
opened up to that line.

Just like in all the old magazines.

Then bolt the head on a 4.820 bore block,and shape the piston to match.
You would end up with a .160" quench area beside the intake valve.

You got it.

Unkl Ian · Post by **Unkl Ian** » Fri Aug 04, 2006 5:52 pm

What I meant to say was:"I have absolutely no idea,
but I'm sure a few pictures from Darin would explain everything".

GREG K · Post by **GREG K** » Fri Aug 04, 2006 8:15 pm

What is a good brand of rubber moulding material to use?

Unkl Ian · Post by **Unkl Ian** » Sat Aug 05, 2006 12:05 am

260 or 360 degrees ?

Darin Morgan wrote: We also use chamber mods which are areas that are laid down to direct the mixture one way or the other or to eliminate vortex generation on the quench pad itself. The spark plug is as close to center as we can make it so having equal quench squish on both sides so the mixture is being directed laterally as you stated. Its hard to explain with words but our quench squish is almost 260° all the way around the chamber. The mixture has no choice but to be moved to center. I have .160 thousands of flat on the intake side of the chamber. It does not seem like a lot but if you take it out, its disastrous to say the least. The engine will drop 8ft/lbs and it will kill the fuel flow 10lbs/hr. I will see if I cant get some pictures so I can explain it better.

Eliminate vortex generation on the quench pads.Interesting idea.
I'll have to think on that one.

Justin Jones · Post by **Justin Jones** » Sat Aug 05, 2006 10:33 am

great thread, needs pictures!

beth · Post by **beth** » Sat Aug 05, 2006 1:54 pm

This certainly is not as interesting as anything Darin may post but it may be of interest to those who work with 4 valves. It shows a 360 degree squish, the squish around the intake is only .100 but the bore is only 3.169 It was only ran about 30 laps.

I couldn't post a picture. Does any body know where I'm going wrong trying to post an image this way? Thanks

beth

Rod Rocks · Post by **Rod Rocks** » Sat Aug 05, 2006 2:04 pm

Darin,
Thanks for sharing the knowledge.

The picture is getting clear, we are able to design a squish band around the entire chamber because of the large bore size and ideally located valves and spark plug. The end result is increased squish action resulting in improved combustion.

A picture is worth a thousand words, this may not be accurate or even close for that matter.

Darin Morgan wrote:We don't use all of it or keep it perfectly flat. We utilize all of it to our advantage by modifications to the squish pad or piston in order to manipulate the air fuel mixture in such a way as to accelerate the deflagration process.

Thats a fancy way of saying we point the air fuel mixture to the center of the chamber over the spark plug so we burn it faster, cleaner and make more power.. The idea is to get the majority of the air fuel mixture over the plug and have it very agitated. We accomplish this by manipulation of the chamber, squish quench pads and piston dome design

Can we now turn to Unkl Ian's intrest?

Unkl Ian wrote:
Darin Morgan wrote: We also use chamber mods which are areas that are laid down to direct the mixture one way or the other or to eliminate vortex generation on the quench pad itself.
Eliminate vortex generation on the quench pads. Interesting idea.
I'll have to think on that one.

Rod Rocks · Post by **Rod Rocks** » Sat Aug 05, 2006 5:10 pm

beth wrote:sorry about the link, I couldn't post a picture. Does any body know where I'm going wrong trying to post an image this way? Thanks

Beth, it must be something to with the storage location Yahoo. I saved your picture and posted it the same as you with no problems. Intresting piston design!

beth · Post by **beth** » Sat Aug 05, 2006 5:17 pm

Thanks for posting it Rod. I'll try hosting somewhere else next time.

beth

Unkl Ian · Post by **Unkl Ian** » Sat Aug 05, 2006 8:19 pm

Yahoo doesn't like hot linking to pics posted on their systems.

Darin Morgan · Post by **Darin Morgan** » Sat Aug 05, 2006 9:25 pm

Pictures

Even amount of quench on both sides and quench about 260° around cylinder.

.150 thick quench on intake side

Vortex generation on quench pad

Chamber mod stops vortex generation

Unkl Ian · Post by **Unkl Ian** » Sat Aug 05, 2006 10:39 pm

WOW !

Thanks for the pics Darin.When you mentioned vortexes on the quench pad,I was thinking at TDC,but your pics explain it quite well.

Thanks very much.