Somender singhs groove theory tried.

klr142 said:

Interesting that ^that^ didn't gather any talk...

But hopefully this will, because I want some insight!

I'm getting closer and closer to convincing myself to get an .036" Cometic MLS headgasket. When I do that, I'm considering adding TWO grooves. Mainly because two are better than none, and mainly because if I only add two, it won't lower the compression as much as if I add 4. The car is going to stay NA for a good while, but it'll eventually evolve into a turbocharged car with good off boost performance and somewhere around 300hp. Maybe 300whp. Not decided yet.

Anyway, I'm interested in hearing if I should experiment with directing flow in other ways than just at the spark plug. There'll be one on each quench pad, and likely at the plug, but tell me your thoughts on going in another direction.

My other question is if I should have the head rebuilt for good measure with a 3 or 5 angle valve grind, and if I should have the machine shop go through and do a very mild port job, mainly to just clean up anything obviously detrimental and casting flaws. The thought of a larger exhaust valve while I'm in there is floating around in my head, but I don't want to hurt anything at lower rpm.

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If you do bigger exhaust valves or keep them the same size, go sodium filled, more bucks but you will thank yourself for the present over the next couple of years. Just remember that if you get too big with the valves, you will end up with an interference engine.

jorrell

klr142 said:

I missed this post before... You'd want to put the dimples where there is an accumulation of carbon in the combustion chamber. Where that accumulation of carbon is going to be, is unknown to some extent, because you're already dealing with a non-stock cylinder head. Best thing to do would be to run your head for a while, pull it, and analyze it to go further from there.

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Hmmmm........ Sounds like a good plan to me.

jorrell said:

If you do bigger exhaust valves or keep them the same size, go sodium filled, more bucks but you will thank yourself for the present over the next couple of years. Just remember that if you get too big with the valves, you will end up with an interference engine.

jorrell

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Thanks for the response. I think what I'm going to do is just go with a mildly ported turbo 530 head with stock sized valves, and then when I go turbo just use a turbo biased cam, such as a KG2T, or something along those lines. My power goals aren't going to be over 300hp, as then I'll have to worry about driveline components breaking a bit more often. I don't want to worry about that too much. 300hp should be good nuff anyway.

As far as an interference engine, I sure hope that whatever cam I end up going with already creates that situation... I'm not worried about changing the timing gear every 50k.

BDKR said:

Hmmmm........ Sounds like a good plan to me.

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I'd enjoy seeing what you find, as well. You forgot to answer my question though, are you adding another groove to the spark plug's quench pad? If not, why not?

klr142 said:

I'd enjoy seeing what you find, as well. You forgot to answer my question though, are you adding another groove to the spark plug's quench pad? If not, why not?

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Don't know. I'm not convinced it would make much of a difference.

As a matter of fact, I can check back through this thread and see if there are any pictures of a grooved 530/531 with a cut in that location. Seeing what the burn pattern is may give a clue.

I'm not sure how bigger valves would make an engine interference - surely the only difference would be where the valve sits in relation to the full height (i.e. the non-dished section) of the pistons...which it'll already comfortably overlap.

cheers

James

This may be for repost police

www.herningg.com/singh/Ionization current analysis.pdf

Interference and testing

Increasing valve size will reduce piston clearance if (a) the piston is domed upwards, or pentroofed (b) if the piston is dished and the valves were but are not now 100% in the dish; and (c) if the valves are inclined as in the B234.




I am wholly baffled why someone does not do a straight a to b comparison. Take car with non singhed head. Dyno it. Also check lowest rpm permitting full throttle opening without pinking. If unable to cause pinking, try with lower octane fuel, or if it's a vehicle with adjustable ignition timing, advance timing. Adjust engine to optimise. Measure again. Return to where it was. Check repeatable.

Singh the head. Do nothing else. Take it back to the same dyno. First compare power and torque figures. Then check for pinking. Then optimise and measure again.

Hassle? Yes, but it would define the result.

Right now everything reported is 100 subjective and not measurable.

Finding out where a head setup will detonate does not necessarily mean much. A grooved head may be more resistant to pinging. At the same time, it may make more power with LESS ignition advance than you're trying to stuff down it's throat, as it's burning more efficiently/faster.

I need to make up my mind if it is worth grooving my 531 head. I am using JV pistons which in my application have very wide dish, leaving about 0.3" ring that makes up the squish area. Would there still be any benefit to grooving this head? I have been putting this off long enough and cannot decide by myself.

Did anyone link this yet? I want to know what you guys think of the one involving the valves. O_O

http://www.allpar.com/fix/holler/valve-prepping.html

http://www.allpar.com/fix/holler/head-porting2.html

Wouldn't those rings on the bottom side of valves fill up with fuel deposits?

On an exhaust valve, for sure, but that's the intake valve.

Boris740 said:

Wouldn't those rings on the bottom side of valves fill up with fuel deposits?

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They will not. I have run Metric Mechanic (patent holder for the modification) version of those valves. I recently popped the head off after running them for a year and they were fine. I have pics, just not uploaded yet.

rogerthechorister said:

I am wholly baffled why someone does not do a straight a to b comparison. Take car with non singhed head. Dyno it. Also check lowest rpm permitting full throttle opening without pinking. If unable to cause pinking, try with lower octane fuel, or if it's a vehicle with adjustable ignition timing, advance timing. Adjust engine to optimise. Measure again. Return to where it was. Check repeatable.

Singh the head. Do nothing else. Take it back to the same dyno. First compare power and torque figures. Then check for pinking. Then optimise and measure again.

Hassle? Yes, but it would define the result.

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The URL in the post above yours has done what you said.

Firemangtp said:

Thats what I was thinking too!
FWIW, my engine (3800's) have ALOT of heads cracked like that with no issues.. but while its out, why not fix 'er up.

Im a little confussed about roughing the intake.. I always hear "port and polish".

On one hand we want them to flow quick and efficient, the other we want s much turbulance as possible.

Im also wondering what kind of benifits you see wit the grooves pointed towards the exhaust port vs the plug.

Keep us updated!

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That is my 782 head for my 2.2 Chrysler Daytona Shelby Z (turbo intercooled). The cracks between the seats is very common and nothing to worry about.

I ran a head with the intake roughed up like that before from Mike. I was happy with it then, which is why I wanted it again. The head is still at my local shop having the valves done.

AB has posted some pics on another forum, from another of his 3 grooved heads. He mentioned "This is the best burn pattern I have seen"

scotts said:

AB has posted some pics on another forum, from another of his 3 grooved
heads. He mentioned "This is the best burn pattern I have seen"

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I'm very pleased with results from angled grooved engines. There is some good
discussion on Vizard's site also.

gofastnews

Cheers

Hello Telvm ,
Sorry to disturb you, i have a few questions about the car on which you made the changes. I like very much everything that you did about the car. I have a kadett with the same engine like you (c20ne). I did some changes . I have spent a lot of money and it still doesnt work, but soon i hope i can get it out on the street. I removed material from the flywheel, i did polish the admision and exahaust. I used the exhaust from c20xe (16 valves). I changed dash board with one from astra F and i want to put a LCD from vectra. Thats pretty much all that i did. I want to ask you for some ideeas about the changes that i can do about my car. I would really appreciate if i could get an answer and maybe even keep in touch, if possible.

Thank you,
Emil

Telvm said:

Hello Turbobrickers. Congratulations for your research and experimentation with the Singh grooves. This is highly interesting stuff and I'm going to have a try on it. Sadly I don't own a Volvo, hope you wouldn't mind talking here about other engines.

My guinea pig is a N/A 2-litre (122 cid) Opel C20NE / 20SEH four-pot SOHC 2V onboard an Opel Calibra. The engine was fitted to lots of Opels / Vauxhalls / Daewoos / GM 'J' cars like the Pontiac Sunbird in the eighties & nineties. This is my first hobby attempt to dismantle, (hopefully) improve and refit an engine. The starring head volunteered from a junkyard.

After consulting with Automotive Breath (thanks again Randy) and reflecting on my own upon the concept I've put the saw-blade and triangular file in action.

My bet is three grooves per chamber. The central groove aims at the spark plug between the valves. The lateral ones are aimed a bit to the sides of the spark plug.

I'm deepening them to the maximum near the chamber roof as I think that's critical.

Standard CR was 10.0:1. After milling the head 1 mm and cutting the grooves it will be close to 11.0:1.


About the theory on how the grooves work, I find these lines written by the great Sir Harry Ricardo in 1927 very inspiring:

"Turbulence ... digs these layers of gas off the wall and hurls them into the midst of the flame ... during the effective period."

​

When the engine is running I'll post here telling how it performs. Please feel free to comment or criticise.

Merry Christmas!

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Hello Telvm ,
Sorry to disturb you, i have a few questions about the car on which you made the changes. I like very much everything that you did about the car. I have a kadett with the same engine like you (c20ne). I did some changes . I have spent a lot of money and it still doesnt work, but soon i hope i can get it out on the street. I removed material from the flywheel, i did polish the admision and exahaust. I used the exhaust from c20xe (16 valves). I changed dash board with one from astra F and i want to put a LCD from vectra. Thats pretty much all that i did. I want to ask you for some ideeas about the changes that i can do about my car. I would really appreciate if i could get an answer and maybe even keep in touch, if possible.

Thank you,
Emil

I'm getting closer and closer to doing something myself, yet, I have too many questions in my mind still.

Tight squish vs. grooves vs. both: Tight squish is good. Grooves are good. Both together, are they better than one or the other?
I was originally thinking rather one dimensionally, and thinking that the grooves kept more of the cylinder clean due to getting most of the mixture into the combustion chamber. With further reading in multiple places, and further thinking on this specific subject, I'm beginning to think that the grooves are working in the opposite direction(well, obviously). Specifically that they allow the burn to expand into the squish bands and thus allowing the mixture to combust above all portions of the piston. Having less tight squish clearances(as AB suggests) would further allow for burning of the mixture that does not make it into the combustion chamber. This would also allow for a greater spread of heat and pressure applied to more of the piston, rather than just the part that is located below the chamber in the head.

General thoughts:
Tight squish = more mixture being combusted in the chamber, resulting in a faster/more complete burn, and a smoother running engine at any RPM, with no known drawbacks(aside from pistons coming into contact with the head when you get carried away).

Grooves = smoother running engine, particularly at low rpm, more complete combustion at lower rpm, with possibly some minor drawbacks/no change at higher rpm, WOT operation.

Then there's the options of what you're doing with your grooves, and how they're working for you.
To be continued... With a few different groove layouts that I will draw when I have time.

Discuss?

For what it's worth, the final iteration of what I do will be a cleaned up 530 head with slightly more aggressive work on the exhaust side than the intake side. Effective SCR will be around 9.7-10.3 depending on if I do grooves, if I do both, or if I just do tighter squish. Camshaft will be the A cam. Car will start out as being LH2.4 and Normally Aspirated, eventually going to low pressure Turbo use.

beware_kadett said:

Hello Telvm ,
Sorry to disturb you, i have a few questions about the car on which you made the changes. I like very much everything that you did about the car. I have a kadett with the same engine like you (c20ne). I did some changes . I have spent a lot of money and it still doesnt work, but soon i hope i can get it out on the street. I removed material from the flywheel, i did polish the admision and exahaust. I used the exhaust from c20xe (16 valves). I changed dash board with one from astra F and i want to put a LCD from vectra. Thats pretty much all that i did. I want to ask you for some ideeas about the changes that i can do about my car. I would really appreciate if i could get an answer and maybe even keep in touch, if possible.

Thank you,
Emil

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Hi B_K. I'll be glad to help wherever I can. Please post here any question you have.