Albuquerquefx

I'm quite interested in seeing some testing done with these grooves, even if it's a "non-repeatable" method like the OP. I'd probably go for a more angular or wedge-shaped cut rather than a trough or trench, and the depth would increase as the wedge opened into the center. I'd also take a file to all the edges and corners to ensure that everything was rounded nicely.

However, I'm still of the mind that a properly clearanced quench area will do the exact same thing, if not better. *shrug*

REDZMAN

That right there is signature material. Oh god that's funny.


As for the thread, I decided last night to go pop the valve cover off of my engine and insert 5 stuffed animals. Acceleration has been greatly improved, and that annoying clack of the cams is gone, I'd recommend it to everyone.

Hah!

Nice to see some educated debate going on, instead of someone calling someone else a b**** and running away. Nice to have you back my pelirojo companion.

I'm going to try to follow this again...

Stocker

That's what happens when you have a crack moderating staff, REDZ - the adults can talk while the children play outside. That's why I like RDT better than EXD. The only bad part is when the thread gets ahead of you while you are living your life and some people wink1.gif are online.

DTN I never said it was a cure-all and why shouldn't he try to sell his idea? If you go to his website it's more about the environment than the money. Our engines run well already, but if you had a nearly-free way to increase low RPM part throttle torque, improve idle quality, and save gas, why wouldn't you try it if the head was off anyhow? There is a lot of "nuh-uh / uh-huh" level arguing out there over whether or not it will work, but I haven't read many reports of people that tried the grooves and didn't note at least some improvement. I have read a LOT of reports from people that had huge improvements. Including full tilt boogie race engines that idle at 500 vs 2000 RPM and, like iheartmyRD, folks who added grooves and 1 point of compression and still run great on cheap gas.

Mechanical octane is not a literal term. It is a term that has been used for decades to describe the effects of quench pads in a combustion chamber. They make it harder to set up detonation, which is why they give it a term related to the factor in higher-rated gas which does the same thing. If you do something else that reduces a tendency to detonate, it is equally as valid to call it mechanical octane as well.

Red, thanks, I had intended to clay the clearances before/after, and Performance Machine in Hutto seems to know their stuff.

iheartmyrd

Btw i would like to clarify that the msd was not bad it was just a loose connection. But it was removed anyway.

Stocker

Wants to be right.

Back on topic: Anywho, iheartmyRD, I emailed Mr. Singh and he said he'd have made the grooves more narrow and deeper, but if you note an improvement, he's still happy for you! fing02.gif

Bullfrog

Thermodynamics class was split at the request of members.

http://www.rdtiburon.com/index.php?showtopic=31094

Albuquerquefx

Ahh yes, much better. Back to the original topic we go!

Stocker, suppose there's any chance that you could do some back-to-back runs when you get closer to ready to do this? Say, throw the head on, do some dyno testing or some gas mileage testing or something, and then pull the head off, insert grooviness, and retest?

That's a lot of labor, and if you're planning on using stock head bolts, means a lot of irritation and potentially new bolts. But in order to really demonstrate whether this works or not, back-to-back testing with some repeatable empirical results is what we really need.

I still think a wedge shape would be better, and the depth of the groove should be quite shallow at the outside progressing to a deeper cut as you move towards the center of the combustion area. More reading on my part suggests that a lot of "huge displacement" carbed two-valve motors have been shown to have a quite positive affect, but dinner-plate sized pistons and two-valve heads and certain carbed characteristics can have quite a large number of fuel atomization issues anyway.

In the more modern fuel injected, 4-valve, high-RPM, smaller bore motors, fuel atomization is already pretty decent. It may simply be that this can help a lot more where atomization is a more pronounced problem, and that more modern motors may be "good enough" to not get so much. But that's all heresay, I don't have any way to back that claim.

radu_rd2

As far as i understand, the main benefit of the grooves is helping prevent detonation. So one would need to check at what kind of compression (or pressure if F/I) one gets detonation with or without the grooves, which is pretty impractical..

Even if the grooves work, I doubt there will be too much of a difference in mileage or whatnot just by adding the groove.

Stocker

Red, I would be tickled pink to be able to do that sort of testing.

At the very least, it would involve a hundred fifty bucks in gaskets and coolant, and double that much again or (much) more in costs for dyno runs. Add the fact that I'd want to do a part-throttle run starting at low RPM (in addition to WOT) and you're looking at a need for something to monitor throttle % in real time. Then you have to consider the cost-increasing variables:

I'm working on a separate head with a full P&P job in addition to the grooves. That'll skew results right there, so I'd have to do before/after with a stock head with/without grooves, then put the P&P head on and do another after run.

Then I'm wanting to use the 1.8L pistons, which would be another thing to require opening up the engine again.

I'd be happy to, but I don't have the time or money, and won't in the forseeable future. Anyone with a car they don't strictly need to be up for a while, and money to do dyno runs, could do a stock/grooved before/after - but it ain't me!

The fuel economy testing is a no-brainer; I do it already to keep tabs on engine health!

The shape of the grooves: yes. Singh uses a hacksaw blade and the shape is more generally triangular in cross-section, deepening nearer the inside of the chamber, and as applicable going up the chamber wall. I'll be recutting mine after the head is decked, so the shape you see isn't final, even though Mr. Singh did say it was "just right." The majority of examples you see on line are big 2V V8s because this has caught on strong with racers. I had never heard of Singh Grooves before reading an article in a Hot Rod type magazine, where the author just casually threw it in there like I should know what he was talking about. Then I spent a couple of hours online and went to bed late, convinced I should try it. With smaller quench pads like we have in a Beta, the effect may be less, but so is everything else including displacement and overall power, and every little bit helps (which you already know wink1.gif )

Albuquerquefx

LoL, if you were going to agree to doing all that testing, I was gonna e-smack you anyway for having way too much time and money on your hands wink1.gif I agree with everything you said in terms of testing; it's just not viable.

Hypothetically, the detonation resistance should be a function of fuel atomization and eliminating mixture stratification. So, if you were to get it exactly right, the car could either be less likely to detonate at a given load / compression / fuel ratio / ignition advance, or could be made to run leaner with compression / load / ignition advance remaining constant.

I don't know which I'd choose, but knowing how I like to poke and prod things until I get a nasty response, I'd probably start dialing on the boost or the ignition timing or the fueling. If you give me the ability run another three degrees of advance under load, or another few pounds of boost at peak, or a 10% reduction in fueling at steady state / low load, then I'm gonna take 'em all! smile.gif