Do Singh Grooves Work?
 

Was just reading the XCFi cam swap thread and someone mentioned cutting Singh grooves into the combustion chamber of their Metro cylinder head.

Any truth to this technique working, or do I need to grab some feed for the unicorn?

...any such "cuts" will both: (a) lower CR and (b) increase chamber surface area (bad for pollutions).

...maybe applicable information? http://www.jeremiahsviolins.com/grooves.htm

Don't get me wrong, I know that there are other ways to get things done; I just didn't know if anyone here had used the technique and produced a positive result.

Ah yes the ongoing discussion abut Singh grooves...

Not a new topic as you probably know already.

So far as I can find there has been NO independent testing or back to back tests either but a lot of discussion and much of it very heated.

The logic is doubtful and the OEM makers have dyno cells too these days so IF it was effective then SOMEONE (Ford , GM , Toyota or whoever) would have paid the licence fees and got ahead of the opposition.

Just my observations.

Peter.

Someone here tried it and I don't recall if they are claiming benefits or not. They never made a big deal out of it so probably "not".

I read some where than those grooves started a crack in the cylinder head.

The better way is: take off a head and look at combustion chamber, if it is uniform in color throughout leave it alone if some potrion is clean put dimples in there (clean means fuel wash condition exist ) dimpling restores boundary layer action and improves burn efficiency.

...+1, but do not make "sharp-edge" dimples as they can become "hot-spots" leading to pre-ignition!

I know that there is a guy over on CleanMPG that had it done to two Saturns he and his son own/owned. I trust him on his numbers, and what was being reported was 65-80 MPG tank averages.

I bet it's a "YMMV" thing. I'd love to grab a second head for my car, groove it, and do some A-B-A testing. But that takes time/money, two of the rarest things in my life...

Some engine builders have used this to increase compression on limited octane. That alone makes it worthwhile for engines running boost or high compression and pump gas. But it has to be done right, and you only need one groove per cylinder. Dimples could likely achieve the same result by raising the detonation threshold.

There was a guy that actually tested these on an engine dyno. He stated it didn't actually increase the power on the two v8s he tried it on but it did move the rpm of the power and torque peeks. I'll try and find a link to his report.

The inventor did get a verifiable power improvement on a Briggs and Stratton engine. However there isn't really much optimization done by Briggs and Stratton on their engines so its not much of a surprise.