SlideRight

Ahh, ok. Thanks for info. =)

rons 00z

iTrader: (10)

that and when you cut that groove you're adding more quench area rather than tightening it. i have yet to see anyone say how good this idea is.

lovescamaros28

The wedge head(turbulent head)...which has a squish/quench area that allows for turbulence,or cooling of the gases at low RPM's,unlike the open combustion chamber Hemi head which is of the non-turbulent type.The Hemi head is typically more efficient at high RPM's.A head such as the wedge can allow air/fuel to seperate at (high RPM's) due to this turbulence.This is basically the theory of why the Hemi head is efficient.Knowing the facts about a non-turbulent vs turbulent combustion chamber,how would you be getting more turbulence by removing the mixture from the quench area.This quench area is what causes the turbulence.To my understanding,the grooves are too slow this quench at higher RPM's.

The Alchemist

iTrader: (19)

If you are going to spend the time and energy and money to remove the head to do this, you're better off just getting a thinner head gasket to cut down the quench distance to better optimize power. It's proven to work, and as long as you don't get stupid with going too thin, it's safe.

So pull the heads, and swap from a stock mls gasket of 0.056" thick to a cometic 0.040" gasket and you be able to run lower octane gas, increase compression a little, and reduce your detonation tendency all for the cost of a new head gasket and some labor.

JonCR96Z

iTrader: (33)

Hemi heads are irrelevant in this discussion. I believe the idea is to give the gases an easier way to escape the quench area, increasing the air speed and introducing more turbulence. Read the article, the whole idea is to increase turbulence. Turbulence makes better air/fuel mixture also helps cool hot spots, which makes more power.

I would think the idea is to do both.


Still waiting on a guinea pig.

lovescamaros28

Sounds like the dumbest idea I have ever heard of for improving HP,besides the old TB air foil mod(lol).Obviously you are going to create hotspots in the CC from the sharp edges of the sin grooves.I could see that they could act as air bleeds and create more turbulence...but any gains on the dyno would probably be negligible.

avb0119

Have not read whole thread. Is of no significance that have ever seen. Also that effort is decreasing effiective quench area. Not adding to it as someone had said earlier. This is nothing trick at all quench is decided on depending on build setup and is then calculated to achieve with decided build specs. Also alot of work is put into chamber design and can't see how that would benefit the chamber. a machininst would not setup his entire build sheet and then cut slits to relieve quench that should have been put into the equation at the beginning. there is just no need i can see power wise or any other reason. and just mentioning this (it all depends on the engine) but could be more prone to leaner areas within the combustion chamber. now im sure it would not make a difference on some street motor making 550. things are not at high enough levels to really see differences, and would say the same on many forced induction engines. But would never see that on a real n/a race engine

JonCR96Z

iTrader: (33)

Please correct us then.

89StripeGT

I have read that the distance to the quench pad from the top of the piston makes a difference in power. This is proven and dyno numbers can show this. Most books say to set the quench as tight as you can without having the piston crash into the deck. This makes sense, in the moments before TDC DURRING combustion (starts way earlier than TDC) the piston squeezes the volume of mixture from the quench pad and violently into the chamber creating homogeneous mixture or somehow supplementing flame propogation.
We all know air flows the path of least resistance so am i to understand that the volume of air between the quench pad and piston is going to squeeze into a .250" groove instead of a 60cc chamber? And what is this supposed to accomplish that the proper quench set up doesn't already?

avb0119

Exactly. Valve closing (just to pick number ) 70 degrees abdc. Timing is (also just to pick a number ) 30 degrees btdc. Cylinder pressure extremely high @ tdc although highest optimaly x amount of degrees atdc. Pressure differential occurs in which pressure is always trying to equalize. Cylinder pressure benifitted signicantly as well as in a major part flame propagation

JonCR96Z

iTrader: (33)

Do we know that airflow takes the path of least resistance? I don't think the idea is to squeeze all that air into the groove. Do they teach "over thinking" at that school?

Exactly? He didn't say anything and it doesn't look like you said anything either.

avb0119

Read it again it was said. But if unclear I understand. Not best at translating mind to mouth. This turbulence is talked as if combustion hasn't taken place yet when it has. The quench pad can make for better air fuel Atomization.the shittier the fuel system the more the difference but is not the main point. Air fuel atomization is not key to take place in the Chamber, should happen when the two are first introduced. If the fuel system is good then will not affect it near as much as the pressure gains from the pressure differental created. Resulting in more power that is The real gain. Any attemp to relieve this is not something to do for power

JonCR96Z

iTrader: (33)

Acting like a know it all is enough for me. I know what stripe said, I guess you didn't understand what I said. So don't get pissy about it.

My point is that just because you don't learn something at a school doesn't mean it isn't possible. With a quick search I can find a few positive results for these grooves. So how can you say for sure what is going on if you haven't tested it yourself.

And there are great minds outside of S.A.M., with results to prove. So what does that say?

89StripeGT

I'm only saying none of the top 5 Engine Masters engines used this idea successfully, I know of zero Pro Stock teams using the idea and I have yet to hear of any Cup engine builder speaking of this idea. While i have heard of textureing, dimples etc. that also isn't used on any winning combinations. I'm not saying the theory isn't possible, but maybe you are the one "over thinking" the whole idea of airflow. If air doesn't take the path of least resistance then tell me why exhaust ports can be merely 2/3the size of intake ports and make power? Is it maybe because the residual pressure in the cylinder is far greater than the pressure inside the header tube? If air didn't take the path of least resistance, then why does air flow through an intake port when the intake valve opens, is it maybe because there is a pressure dop and there is less resistance to flow into the cylinder rather than out of it?

They teach how to think with logic at the School of Automotive Machinists, but if you still think i'm "over thinking" bring that trans am down to Houston with some money in your back pocket

JonCR96Z

iTrader: (33)

Do the heads used on the cars you mentioned have quench pads? And what works on one thing may not work the same way in other applications. That's logic.

Just because air it seems to follow the less resistant path may not be for that reason alone. I'm sure it doesn't go the way of most resistance. However, the grooves in those heads would allow for a lower pressure area at TDC than the surrounding area. Thus causing some of the airflow to follow that path towards the combustion chamber which ultimately has an even lower pressure. So isn't that what you were arguing to begin with? Maybe I confused "over thinking" with "under thinking".

What does my car have to do with anything? Do you have a faster car? Does that mean that you're smarter? There are lots of faster cars than me, that weren't built by SAM alumni. So what?

rons 00z

iTrader: (10)

on here or google? can you provide us with that? also, have you done these yourself?

JonCR96Z

iTrader: (33)

It's not about your school, but it just so happens that 2 guys from SAM came on are acted like its what they said or nothing. I personally know a guy that went to SAM and he acts the same way, but he really doesn't get it.

Everything that you've said may apply in most cases, but there could be a possibility of something else going here. True it may end up 99% of the time just ******* up a head, but who's to say.

I googled it, seems like most of it was from mpgresearch.com. There were a handful of claims of better low end and MPG, but no real proof or evidence so no real need to post. All that I saw were on small engines (4cyl).

rons 00z

iTrader: (10)

ok so then whats the problem? if those are just claims and you're backing this yet never tried it yourself what proof do you have that this actually works? because, in every other scenario it doesnt. mainly of what everyone else said hot spots and the increase in quench area. those two things are major reasons why this wouldnt work in a internal combustion engine. now maybe this technology applied to a air pump that doesnt produce thousands degrees in exhaust heat i might agree but for us in the auto performance world i wouldnt chance it.

JonCR96Z

iTrader: (33)

There is no problem. I'm not backing anything. I'm trying to get some one with some time to kill and some spare heads to give this a go.

Yeah, you can read a lot of things that people say on LS1tech, that doesn't make any of it true. It does sound like a goofy idea, and I'm sure that I would never do it myself even if some gains were had.

If it's tested thoroughly and fails, then I'd give major props to whomever tried it. Won't bother me either way.

lovescamaros28

I want to see a dyno comparison between a head with sin grooves and one without.They would have to be the same cylinder head.Until it has proven a substantial increase in HP/TQ,I am not convinced.