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Discussion Starter · #142 ·
curtis73 said:
...Even if I didn't like Singh's grooves, I wouldn't discount it unless I had cold hard facts, and I would try it for myself. I certainly wouldn't be so absolute about something just because its "new." Just because you THINK it doesn't work doesn't mean it can't...

Curtis, your being logical, I consider that a great gift.
 

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Discussion Starter · #143 ·
curtis73 said:
Hey, why do you have this passion? :)
I have been modifying engines for over 30 years; I still have my first 327 and 454. Performance is my passion, having the knowledge and skill needed to port a set of heads is priceless.

For the first time in those 30 years I have found a simple modification that changes the characteristics of the performance engine. I compare this it to replacing a points distributor with capacitive discharge. I have spent the last two years learning why it works and how to improve it. As more people get involved that learning process will speed up with ideas from others.
 

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QuenchPiston said:
I really don't know how to take this.
Obviously you didn't take it well, you sure do get wound up kind of easy. :eek:

You did mean the Aries and Reliant right? Seriously, you had to have anticipated some ribbing for bringing those up.

I have several friends that are mechanics and were back when the K cars first came out, to a man they have nothing good to say about them. I know several people that have owned one (or more) and none of them have fond memories of theirs. My wife's niece currently owns my late F-I-L's LeBaron K-car convertible. It sits in the driveway because the electrical system keeps having failures and they can't find parts for it, she had to buy another car to get her around. She won't part with it though because it was her Grandfather's. If Grandpa were alive today he'd tell her to scrap the POS.

Also, comparing sales numbers of a limited usage car like the F-body to a platform that came in several multi-purpose configurations and was aimed at a broader customer base isn't really a fair comparison now is it? If it makes you feel any better, I don't have too high of an opinion of 3rd Gen F-bodies either.

I do see merit behind the Singh's Grooves theory. Not saying it does or doesn't work but I'm willing to give it consideration. You'll never change my mind about K cars though. ;)
 

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Hippie said:
Obviously you didn't take it well, you sure do get wound up kind of easy. :eek:

You did mean the Aries and Reliant right? Seriously, you had to have anticipated some ribbing for bringing those up.

I have several friends that are mechanics and were back when the K cars first came out, to a man they have nothing good to say about them. I know several people that have owned one (or more) and none of them have fond memories of theirs. My wife's niece currently owns my late F-I-L's LeBaron K-car convertible. It sits in the driveway because the electrical system keeps having failures and they can't find parts for it, she had to buy another car to get her around. She won't part with it though because it was her Grandfather's. If Grandpa were alive today he'd tell her to scrap the POS.

Also, comparing sales numbers of a limited usage car like the F-body to a platform that came in several multi-purpose configurations and was aimed at a broader customer base isn't really a fair comparison now is it? If it makes you feel any better, I don't have too high of an opinion of 3rd Gen F-bodies either.

I do see merit behind the Singh's Grooves theory. Not saying it does or doesn't work but I'm willing to give it consideration. You'll never change my mind about K cars though. ;)
I really apologize over my wording, I am not the most eloquent writer in the world but one thing I have learned from college writing and debating is literally taking things apart with a fine tooth comb. Perhaps I get carried away.

That story about the grandparents K car is funny because I am dealing with the same thing. My father will not scrap his moms car even though she past away over 10 years ago.

Trust me, you wont find me driving a K car around any time soon. I used it purely as an example of shear disgust and skepticism by automotive hobbyist and it kind of worked, I think.

I never tried the groove but then again most people smell their hand after the accidentally put it in dog dodo. I was really skeptical of the thong when it came out too, now I wish I had stock in the underwear companies. I asked a few women why they were thongs and their reason made perfectly good sense to me.

I kind of compare the groove to the fast burn heart shaped chamber. Who in their right mind would stick that thin part out into the combustion chamber like that? Wouldn't it create more problems with localized hot spot? It worked though.
 

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QuenchPiston said:
I really apologize over my wording, I am not the most eloquent writer in the world but one thing I have learned from college writing and debating is literally taking things apart with a fine tooth comb. Perhaps I get carried away.

And I probably should have used a smilie or two in there to let you know I was just teasin'. We're cool. ;) :cool:

BTW, the local "classic" car lot has a super clean K-car Limo on the lot. :pimp: The first thing that entered my mind when I saw it was "Why?!"
 

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automotive breath said:
Here's a picture after the mill and valve job, these are production vortec heads 062 castings. The chambers ended up at 60cc, final compression ratio will be calculated when the deck hight is measured.

how were those cut? and what with?
 

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did you have the valves in when you cut?
i havent really read any of thread, so many posts, what are the purpose of those?
 

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Discussion Starter · #151 ·
Most of the heads I cut the grooves with a port job so the valves are out. When somebody comes for just the grooves, I leave the valves in. If so I make sure the ports are taped up and I get everything clean when I’m finished.

I consider the two primary functions of the grooves to be a channel(s) to direct the squish flow to a desirable location in the chamber and a method of relieving end gas pressure.

Runn141, I noticed you like the S10, I had a grooved 355 in this one for a while.

 

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automotive breath said:
Most of the heads I cut the grooves with a port job so the valves are out. When somebody comes for just the grooves, I leave the valves in. If so I make sure the ports are taped up and I get everything clean when I’m finished.

I consider the two primary functions of the grooves to be a channel(s) to direct the squish flow to a desirable location in the chamber and a method of relieving end gas pressure.

Runn141, I noticed you like the S10, I had a grooved 355 in this one for a while.

yeah that looks good, theres not a bolt i havent turned on one of them. but without a v8 i wouldnt drive em.
 

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Just a sidenote: The idea of using shapes, lines, circles, and other methods to induce turbulence is not a new idea at all. Diesels have done it for years. An excerpt from www.thedieselpage.com :
Fuel is injected directly into the prechamber a few crankshaft degrees before the piston arrives at TDC (Top Dead Center). The hot compressed air is swirling counterclockwise inside the prechamber throughout the compression stoke, then swirls clockwise as fuel is being injected and combustion begins. The internally spherical shape of the prechamber maintains the swirl as the piston begins its downward push, and the hot expanding gases rapidly begin exiting the prechamber and out onto the piston crown. This high-swirl action gives both the burning and unburned fuel vapors every opportunity to mix with the oxygen molecules present in the hot gaseous mixture. A more vigorous swirl along with higher combustion gas velocities improve fuel/air mixing and combustion efficiency.
here is a piston from a 6.5TD showing a swirl-inducing cavity in the piston



Here is a cross-section of a 6.5TD head showing the prechamber



Here is a photo showing some of the prechamber cups, all experimental in a BSFC experiment done by www.thedieselpage.com which can be viewed at http://www.thedieselpage.com/features/65fueleconomy.htm . The cups discharge ports all have slightly different profiles and some dramatic differences were found with fuel efficiency. This does not prove that Singh's grooves work, but it does lend credence to the fact that tiny, subtle changes in a combustion space can have dramatic effects on turbulence. I don't think anyone would argue that increased turbulence is a good thing, so if a slight change in a 1/8" nozzle opening can have such dramatic effects on a diesel, I would think that a 2" groove might have as much of an effect. It at least piques my interest.

 

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Discussion Starter · #156 ·
Here's an example of a similar idea where the combustion chamber is in the piston top and the head is flat. The squish jets create a swirl in the centrally located piston dish.

Quote from another forum:

Earlier Stef mentioned SAE paper 1999-01-3664 on the in piston squish jet combustion chamber used with a flat cylinder head, here’s the results of that testing:

Compared to the engine with the bathtub combustion chamber, the experimental investigation shows that engine with the squish jet turbulence combustion chamber gives better comprehensive performance. The combustion process shortens, the lean burn limit extends. At WOT speed characteristics, the maximum power output increases by 25.7%, the average specific fuel consumption decreases by 12.9% and the average emissions of HC, CO and NOx decrease by 31.4%, 91% and 5.6% respectively
 

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Discussion Starter · #157 ·
curtis73 said:
... I don't think anyone would argue that increased turbulence is a good thing....
Many people don't understand the importance of turbulence in the combustion chamber. Here's some good reading on the subject.

squish action

... Without turbulence in the combustion chamber we would burn the mixture at the laminar burning rate which is ten to twenty times slower than the turbulent rate. This would make practical engines that rev higher than about 1500rpm an impossibility...
 

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just to re-cap a bit. for this to matter in a head, you need to have quench, and the quench area is the flat part of the head where the piston will squish the mixture. this means that in my heads pictured here, where there is absolutely NO flat area, that using grooves would be a total waste of time right?


i didnt notice before, but there is no flat area at all to speak of. maybe a half inch at best, so i guess i'll just wait till i build a different engine.
 

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This thread started with a civil exchange of ideas that shortly thereafter went out the window.
Someone explain why this pissing match has not been dumped. Eleven pages of the same crap, there are three sides, those that swear by it, those that would give it a chance, and those that will not believe in it unless there is scientific proof that it works. Apparently no one is willing to put up the cash to prove or disprove the theory. I have seen less get dumped quicker. How many more pages does it need to go on?
 

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1ownerT said:
This thread started with a civil exchange of ideas that shortly thereafter went out the window.
Someone explain why this pissing match has not been dumped. Eleven pages of the same crap, there are three sides, those that swear by it, those that would give it a chance, and those that will not believe in it unless there is scientific proof that it works. Apparently no one is willing to put up the cash to prove or disprove the theory. I have seen less get dumped quicker. How many more pages does it need to go on?
I read over a page that had posting rules on it and it didn't say that there was a set limit as to when a thread need to be stopped. Can you help out on this one?
 
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