Not to be terribly augmentative, but I'm agreeing with Rick WI.

I asked both my engine builders, one builds a 1000 engines a year for circle track from Nascar to SLM, drag all classes, and marine all classes, if he has even herd of such thing. He doesn't or has never heard of such things as any kind of grooves for any reason. He hasn't even shown the dimpling makes any difference that was all the range a while back.I shpwed him the pics on here and responded with sarcasm. In fact he made fun of the valve jobs. He said he could find the amount of power in a good the valve job.

This tells me this Sommender's character doesn't have enough backing in the R+R department to be considered by any. I can't believe that this guy has something all figured out, yet two of the biggest engine designers in the USA and GM or Chrysler, or Ford, Haven't realized that these grooves work. Come on now!! It cant possibly be tooling, a redesign issue, or some other money issue that keeps these five from using it. If it worked, someone would using it by now. Nascar doesn't have a head rule for this yet, if it worked, they would be using it too.


The tan stuff you see in your pics, look like fuel washed the carbon to me. See how it wraps the intake along the head and cylinder? If the grooves help, why don't they appear to be fuel washed too?

http://www.revsearch.com/grooves/grooves.html

Owning a dyno cell and doing lots of dyno work this mod does not appear to support much benefit in this particular application. Claiming for instance a torque increase of 6.5 ft/lbs in the 2700 RPM band is about 1hp. That is well within a variablility you'd see on a back to back test session. No supporting data on BSFC would also indicate no support for efficiency increase either. In fact noting that BSFC did not really change at the conclusion of this test as borne out by the lack of statistical power gains seems to again show no affect by the grooves. At least in this test.

For all practical purposes, and based on doing hundreds of dyno tests, those curves are the same. I could show more of a variation doing a sweep from 2000 to 6000 and then 6000 to 2000 on the exact same engine.

Granted, you do this yourself it costs nothing and it appears from this test, statistically and seat of the pants, does nothing, your out nothing. If you PAID someone to do this and then paid to have it tested and it showed these results you would probably have different feelings.

Absolutely. Then again in my case I'm not looking for power, I'll be making plenty for what I'm going to use the car for I just want a little detonation "cushion" in case I'm out on the road and have to fill up with 87. I have read varying opinions on the ability to run on 87 Octane with a DCR in the 7.6 to 7.8 range, most say "no". Right now to maintain optimum quench but lower my DCR a few tenths I need to either remove some material from my combustion chamaber or the D-cup in the pistons. I suppose taking a little out of the piston wouldn't really be any more difficult than cutting grooves in the head........... I still have an open mind on it though.

Two things I have found to reduce the onset of detonation is feeding the carb, throttle body with outside air (cowl induction/ducting and so forth) as well as slightly cooler thermostat settings. Even a drop from 180 to 170 can help, although it's almost impossible to find 170 thermostats these days.

My latest 355 is 9.4 with iron heads and 180 thermostat and "0" deck height. I run 87 all the time. Summer time is tough and have to lower the timing some but can get along fine on the cheap stuff. Quench is .035 with flat top pistons. Base timing is 14. Base+mechanical is 34 all in @2600, no vacume advance.

Way ahead of you on both counts, I can still get 165 thermostats arund here, lots of old Chevy grain trucks still chugging along around here and I have been looking at different options for ducting cold air from the cowl without altering the outward appearance of the car.

'jmark', what are you running for a cam, trans and rear gears and what is your 355 in?

I have a Two Ton T-Rex of a '76 Monte Carlo with a 200-4R and 3.73's and as if the aerodynamics weren't bad enough it has T-Tops. I can retard the cam 4 degrees and drop my DCR a couple tenths without losing much torque and I gain at my HP peak but I'm still at 7.6 and I don't want to run a larger cam. I suppose with the torque this will put out and the 3.73 gears I won't be lugging it and putting it into a situation where it might detonate and maybe I'm getting carried away but guys I don't envision the quality of gas improving, I think it will only get worse and I don't want to have to tear this down again and start over 5 years from now because I can't buy gas it can run on. On the other hand I don't want to compromise on my combo now because it is EXACTLY what I want for this car. I'm looking for that "magic bullet" I guess.

Hippie, I can help you exceed your goals, what's the specifications you are using to determine the compression ratio? The reason I ask is I'm running 10:1 compression in the Suburban I use to tow my race car, stock camshaft. I want to compare numbers.

Send me a email, I have information you will be interested in.

automotivebreath@hotmail.com

Rick, Actually this test was very informative. If you are interested in some of the things that were learned, I was involved from a distance.

Hippie.....'77 chevy truck with steel frame camper. 3:41 gears, th350 trans. Cam is the Crane 272 hyd. SpeedPro hyper coated pistons. Nothing special but runs great.

Maybe someone can ck my CR, I just took the numbers out of the book when selecting parts.
Flat top, 4 valve relief pistons, "0" deck, 76cc heads (882's). Stock stroke 350 crank. .030 over 350.

this here i'm about to say doesnt really ad anything to this post. i still havent read all those links from page three, but i have talked to my machinist who tells me that over 20 years ago they were trying this and it didnt work. there was a MAJOR difference in the depth of the groove tho in that back then they were making them deeper, about like a valve relief in a piston he told me. i told him the grooves we were talking about were with a 1/16 in bit. he hasnt heard about it but was skeptical just from what he knew about.

rick wi, i am wondering about all those dyno pulls you have done, if you know of anybody who actually had these grooves done on their engines and if there was any difference. that is pretty much the only way to know whether or not this works. however, with dynos in mind, the pop hotrodding engine masters challenge has some pretty inovative people in it. if these grooves, or the variation mentioned above were being experimented over 20 years ago, i would think anyway, that one of these guys would be using them if they worked, after all there is a lot of money to win.

bullheimer you highlight the most important point, one that gets often overlooked. “IT WORKS”

When all is said and done, it really doesn’t mater what I think or someone’s engine builder thinks or what the dyno numbers read. The bottom line is if you do this to your engine and you like the results it was worth the effort.

I lost count of how many engines I have grooved, over 20 and I cannot keep up with the demand. I have never heard of someone that wasn’t happy with the results, never. I suppose they could all be wrong and they are giving the grooves credit when it was actually something else that provided the benefits.

As for your idea about cutting grooves at right angles, it’s been done and the results were good. I personally like a straight grooves pointing directly into the approaching flame front or at a slight angle. It’s all because of the way I picture the combustion process happening, of course my theories could be all wrong.


You mentioned engines masters, this comes to mind.

http://www.popularhotrodding.com/te...uild/index.html

Well, first of all, power gains are not the reason for grooving. Detonation tolerance and fuel consumption are. The other thing that they failed to test in that article is rejetting the carb. Some folks with grooves are running 17:1 A/F. That saves tons of fuel, and in some instances has shown larger power increases.

Remember, BSFC and MPG are only vaguely correlated. BSFC is how much hp gets extracted from a pound of fuel. That says nothing about MPGs.

If you think that the benefit of grooves lies in BSFC and HP, then I agree with you, they don't do s#!t, but as far as allowing far leaner mixtures, lower fuel consumption, and higher compression on less octane, they have been shown to excel. That's something that neither you nor the people who did that test seem to grasp.

Curtis, your wrong. BSFC, A/F, torque and power all relate to how efficient an engine is and expected MPG.

What is better for mileage, an engine that can make 40 HP at a .39 BSFC or an engine that makes 40 HP at .55 BSFC? Jeez louis, data is data. The data showed no difference. If the grooves had an impact it would show up in the data. The EGT data is so nebulous in what it's legend is tracking it's basically worthless. There is no definition there as to what the data is. Looking at the power curves, BSFC info, it's a mirror of one another before and after.

AGAIN, all the information you are quoting is ANECDOTAL as to your claim of A/f potential and MPG results. If I find 10 people that say Tornados increase their mileage does that mean it's a valid product? I think not, it's a crock of sheep dip. Folks say mothballs work, cow magnets and on and on. Unless there is documentation rather than internet folklore it's impossible to say it's true. That's my point.

Automotive Breath is ALL OVER the internet claiming the same verbiage as the fine Dr, from India. That's fine, it's his right. No reason other can't say, produce the data that verifies the claims.

Automotive Breath, feel free to post the interesting results from that dyno test. No need to hide it between you and I in a PM.

BH, I have never had an engine on the dyno with the grooves. If I get the chance and time I'll happily discuss the grooves in the tops of the pistons with Ross on the reference link to Tony's engine. If anything material comes of the discussion I'll post. Maybe if I'm lucky I'll see Tony there. I will CERTAINLY ask him face to face about it. I know what Rehr Morrison thinks of the technology.

This really should not be difficult. This "idea" has been around now by the fine Dr, since what 1990 or earlier? Somehow or somewhat documentation must exist which verifies on an independent basis the claims. There has to be some non anecdotal, factual, independent, non biased data somewhere.

And for heavens sake Curtis how in gods green earth is running 17:1 air fuel going to "show even larger power increase"? How in the world are you going to make power that that A/F ratio?

We just disagree on how much. We both just said that they are related. So if I'm wrong, you are too BSFC is how much power it extracts from the fuel you give it. MPG is how much fuel is used per mile. Since there is no way to know how that mile is traversed, how can it always be the same relationship? Its quite possible that you can improve BSFC and lose MPG all things remaining equal.