Stingxray

Anyone used this trick........ Grooving the quench area ??? Claims to give power & mileage. I just happen across it while reading articles to reassembling my AFR heads. Thoughts & a Link
I might try it
http://somender-singh.com/content/view/68/49/
http://somender-singh.com/content/view/7/31/


http://jeremiahsviolins.com/grooves.htm
http://www.v-twinforum.com/forums/v-...article-4.html

Hitch

I just have to think that if it helped that AFR would have sent my heads to me this way..

JMO

Dave

mechron

those are singes grooves, they were muched talked about and were reffered to on another forum. it makes sinse to me, but i never wanted to destroy a set of heads to find out...

Shurshot

I know that grooving the block where the intake charge enters the cylinder yields a net improvement but this is the first time I have seen the head surface done

Doug

BADBIRDCAGE

Looks like a great starting point for a fire slot.

Rich

wmf62

hmmm, looks like it would carbon up on a driver.
Bill

mechron

i spent hours finding this, read it and scroll down through the pages to see the pics, they are good:

http://www.hotrodders.com/forum/some...hlight=grooves

Stingxray

I agree with your questions ...until I see the actual pattern on the combustion chamber and piston. researching the links....you can see Clean areas where no flame travel has occurred on the un-grooved model. Seems like clear proof. Carbon will not build up in a high flow area. 0.02

64_365

Interesting, very interesting....

Hmmm, I would love to try this on somebody else's brand new AFR heads.

Something I noticed about Somender Singh's site was lots of claims of improvement but other than photos of combustion chambers, I didn't see any test results.

Stingxray

Interesting concept It helps burn efficiency(hense power and knock) - when the piston comes to TDC, that groove creates a high pressure surge of air into the quench area that helps ditribute the mixture in the combustion chamber. It's a wonder........ I haven't herd of this before? I'm running higher compression than I should on a street engine. Results seem to be less detonation also. I want to read up in Supercharger testing too.

cv67

No.


They missed the crack.

ZLX

A dredged river flows faster than a non dredged one.. so I could
see some merit to the idea.. BUT

River dredging is done in the direction of flow.. and the cuts in the
head are not in the direction of flow.

"Every heresy has an element of truth"... so be careful.

I'd say use the trick on a set of Junk aluminum L98 heads and
back it up with Flow Bench numbers...

Also might look at NASCAR heads... if it worked, you'd see it there.

Shurshot

I liked your comments but the last two make me wonder a bit

For sure I would not want to experiment with my Brodix heads that already have a lot of additional money spent on what was not cheap to start with....... however will junk heads reveal the same benefit that high flowing heads will?

Kinda like will one injection of steroids make a fat guy run faster?

Regarding NASCAR heads...... is this governed under their rules and if not would we see what they really use?

I was once shown something that was claimed to have to do with the header collector used by one NASCAR team by somebody who could know that was nothing like I have ever seen anywhere else.

I could see the theory behind it but how does it stay secret if it really works ...... especially with all the rules and inspectors that are pretty attentive to details.

just my .02

Doug

63 340HP

The theory of the chamber grooves have been around a long time, and it keeps changing.

Some think it helps direct the exhaust into the valve pocket & port as a highly domed piston comes up (from the flow theory experts - two photos reflect this theory).

Some believe the grooves between the intake & exhaust prevent overlap contamination during the period the intake and exhaust valves are open. The grooves are supposed to set up a turbulent air-dam between the valves (from the overlap reduction theory experts - two photos reflect this theory). Others simply believe the grooves tumble the airflow on the intake stroke and move the mixture down the cylinder (as opposed to across the chamber to spin down the chamber wall).

Some believe the grooves add turbulence at the top of the compression stroke, and enhance the ability to exploit lean mixture ignition into the quench area (much like a CVCC recess, in theory), while some others believe it allows some chamber cooling advantage (to allow a higher compression ratio with an iron head).

The single groove in the two stroke photo head is intended to add turbulence above the exhaust port to (somehow) direct flow to the window of the exhaust port as the piston drops in the cylinder, and as the intake charge is pumped into the other 2/3rd's of the cylinder.

When I was playing with motorcycles i pulled apart many engines (mostly Yamaha two-strokes and Honda four-strokes) with added grooves in the chambers. I never had the instrumentation to tell if they improved anything (other than the engine builders reputation). I do know they did not add reliability (because, otherwise, the engines would not have ended up on the workbench).

You would think that in the efforts to curb emissions and increase fuel mileage, a simple modification like a groove or two would be in a factory head (and they are not). I have looked at some wild heads by Jim Fueling and other experimenters and none of the production chambers have grooves. None of the more modern pentroof & polysphere/fast-burn chamber designs use grooves, even in the fully machined chambers where it would take minimal CNC code to add a few.

I have been told (by the groove experts) that they help a poor chamber, and do little on a modern chamber. With this in mind maybe they would help an old set of 461 camel hump heads (so, who gonna cut a set of old heads to throw on a dyno to find out)?

They do make for interesting photos (as do the piston crown burn pattern photos from some groove advocates).

ZLX

Unless the rules have changed recently.. there is no limit on head
porting.. All Cup teams must begin with the Cup specific head supplied
by their particular car's manufacturer.. (Chevy, Toyota, Ford, etc)
.. beyond that.. flow modification/improvement is the responsibility
of the Team's engine department.

To the original poster... Chapman Racing has provided porting services
to NASCAR Race winners... better to spend your money with someone
who has proven results vs. with someone who is experimenting or trying
to prove theories.... ask for CFM numbers.. the flow bench don't lie.