I found an article on the web about Somender singh (can't add a link right now).

It was about creating turbulance on the cumbustion chamber. He ground some grooves in the Quench area of the head to create a vortex, mixing the air fuel ratio beter to create a cleaner, faster, more complete burn.

According to the findings, it creates about 20 to 42% more torque in the 1500 to 2500 rpm range.

The other thing they have found is, it significanlty DECREASES the CHTS.

Now, being a sceptic, I have my doubts, but the more I read the more I am interested.

It may be but it makes me think

There is likely something to it. The new diesel engines have grooves in the pistons for the same reason. The VW is expected to get 75mpg from a diesel motor. See last month's Popular Mechanics.

COOL!!

I eventually want to build a super 2liter. IF this does what he claims, it would play along nicely with this type of engine.

They also say to use 10:1 compression and .070 quench. That may be a bit tasking to do with these engines.

I'm running 8.2:1 right now with .037 quench, might be woth it to get a second set of heads and give it a try :idea:What the Hell!! won't lose much but a bit of time!

http://www.metacrawler.com/info.metac/sear...417/top/-/-/-/1

a link to a search site shows a lot of items, here is a good one:

http://www.rexresearch.com/singh/singh.htm

wow, thats a great read...seems to be a few years old, I wonder what has become of him today??

The Singh grooves are still quite popular. I am having them cut into the heads on an engine I am currently rebuilding. I figured that it cant really hurt to try it. The biggest risk is cracking on the heads though. Typically you would want to run about .040" quench to get the most out of the grooves. I will be trying for 9.5 or 10:1 and see what happens.

One intersting note in one of the articles is a person took and engine, dyno'd it WITHOUT the grooves , placed a different set of heads WITh the grooves, NO timing changes or tuning changes.

All things being equall, it showed a +6hp GAIN. and much smoother idle qualities.


on and 8 cyl, that's 3/4 of a Hp/cyl gain. On a type IV 1.5hp. WOOHOO!!! cheap and easy HP!! LOL.

I have not read about any negatives YET!

One article I read said to rn .070 quench and 10:1to maximize efects.


TAKE PICS PLEASE WHEN THAY ARE DONE

Check out the website mpgresearch.com There are some interesting discussions of the grooves there. One guy has been doing a number of engines, and said that .040 was working out the best, since .070 starts to get a little on the high side. Some people cut the grooves and expect magic to happen, and suddenly get more power. The grooves themselves will not going to really add anything to the engine. What they do is they enable you to run higher compression with less chance of knocking, and reduced head temps. This is where the power gains come from. And as you mentioned, this is primarily for lower engine speeds. Some people expect to see big gains on the top end, which wont happen. But it can be used effectively for helping to bring up the lower portion of the torque band.

Could someone explain in layman terms what this quench is and what the numbers like .070 and all that jazz really mean? I'm lost in this discussion and I really want to understand and learn. as one day I would like to rebuild my engine and use some of this newfound knowledge.

I'll read that , thank's. Most of a DD's life is spent in that rpm range and if all the hub bub is true that's a good thing. according to Jakes read on the super 2l, he and Len spent quite a bit of time figuring out how to make good intake air velocities at low rpm.

I am soon going to do a FI project on a 32hp briggs and stratton that lives it's life to make the most power at that rpm range and MAX rpm is 3600, this is a gooood candidate for getting groooovy .

This can be used for some effectiveness.. Most people would never get it correct because every chamber and engine will have a different optimum position for the groove (s)

Yes I tried it once, but unless you have seriously good chamber filling and a dose of CR the chamnges are not noted..

For some results on the effects of quench look at my post here on the 170HP 2056- we re-tested it today with less deck/ more quench and I posted the results.

The idea is almost as old as the ICE. I read an article by Jim Feuling on chambers many moons ago ( I may have been a teenager) that discussed dimples for the same reason. It is a band-aid for ports with poor wetflow characteristics. Hotrodders put them in flat heads before most of us were born.
Observe a chamber that has been run for a while (long enough to develop some residue) and dimple the areas that are washed down.
Don't dimple areas that have a even tone.
The best route, however, is to avoid poor wet-flow characteristics. (Ever wonder why bigger valves don't always make more power?)

With proper port configuration (and remember the port doesn't stop at the valve, it effectively extends into the chamber about a half inch), seat I.D. and profile, valve size and profile, chamber shape, mixture quality and ratio, exhaust, and cam (plus gearing, too, so the engine operates at the optimum RPM as much as possible) for the given application and you won't need the extra stress risers in your chambers.

If all of the criteria for proper combustion sounds daunting, it's because it is. That is why the research goes on forever and the development never ends.

All of that said, I reserve the right to change my mind regarding the black art of combustion theory at any time! One must keep an open mind about such things and remember that in the absense of the most ideal situation, what ever gets the job done the most effectively is still the way to go.

If you try this, be very careful to not create stress risers. And keep in mind that without observations of the actual chamber to be modified after it has operated with all of the criteria listed above long enough to establish residue patterns, where to place the dimples (or gouges) is just a guess.

BTW the Super 2.0 chamber is so small there isn't much room for dimples, which it doesn't need as the port velocity at the chamber is extremely high.

In short,that's the distance between the top of the piston and the flat spot on the head in the combustion chamber. Quench or squish are the same thing.

.070 is 70thou of an inch

.040 is a tighter tolerance, 40 thou. of an inch

[/quote]

In short,that's the distance between the top of the piston and the flat spot on the head in the combustion chamber. Quench or squish are the same thing.

.070 is 70thou of an inch

.040 is a tighter tolerance, 40 thou. of an inch
[/quote]


Now I understand. Thank you Sir!