rags Posted March 19, 2009 Share Posted March 19, 2009 Its not snake oil, but its a band-aid for poor combustion chamber design. If you do things right to begin with, you don't need to do this extra work and lose compression in the process. Exactly my thoughts. I wouldn't be doing this to my LS1 motor but a 30 year old head design on top of a short block with less than optimal configuration tells me I have nothing to lose! Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted March 19, 2009 Author Share Posted March 19, 2009 Exactly my thoughts. I wouldn't be doing this to my LS1 motor but a 30 year old head design on top of a short block with less than optimal configuration tells me I have nothing to lose! And that's why I'm interested. Obviously modern twin cam, 4 valve setups have very little space or need for performance improvement, but head like ours? It seems to be worth a shot. Guess I'll add a 280zxt long block to my list of stuff to find in the pnp next week to try this on. Quote Link to comment Share on other sites More sharing options...
blue72 Posted March 20, 2009 Share Posted March 20, 2009 If the Singh grooves are meant to be carved into the quench pads on the head, then would it pose any benefit whatsoever on a dished piston motor? Seems to me that if they're in the quench areas that any "benefits" could only be realized with a flat-top piston equipped motor. Just my 2 cents. Quote Link to comment Share on other sites More sharing options...
Globerunner513 Posted March 20, 2009 Share Posted March 20, 2009 I think there was a thread about this here a while ago. I remember a lot of good discussion, but i'll have to look for it. Quote Link to comment Share on other sites More sharing options...
rsicard Posted March 20, 2009 Share Posted March 20, 2009 Good quench yields better turbulence. Adding a groove towards the spark plug may add even more turbulence. That would promote even better burning of the mixture. Comments please. Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted March 20, 2009 Author Share Posted March 20, 2009 I think there was a thread about this here a while ago. I remember a lot of good discussion, but i'll have to look for it. It wouldn't mention singh in it then, since only four others do. Three of which only mention it once, and the fourth was about some spanish 'tuners', and the comments were all along the lines of 'why are they doing so much wrong if they've heard of this technique?' Quote Link to comment Share on other sites More sharing options...
johnc Posted March 20, 2009 Share Posted March 20, 2009 I wouldn't be doing this to my LS1 motor but a 30 year old head design on top of a short block with less than optimal configuration tells me I have nothing to lose! Except compression. Quote Link to comment Share on other sites More sharing options...
rags Posted March 20, 2009 Share Posted March 20, 2009 Which should help a turbo motor with an 8.5-1 ratio. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 20, 2009 Share Posted March 20, 2009 Exactly my thoughts. I wouldn't be doing this to my LS1 motor but a 30 year old head design on top of a short block with less than optimal configuration tells me I have nothing to lose! Have you looked at the LS1 chamber vs a P90 for example? They're really not that different. Quote Link to comment Share on other sites More sharing options...
rags Posted March 20, 2009 Share Posted March 20, 2009 Yeah the chamber shape is similar but the ports are extremely different which I think will have a huge effect on swirl. I'm not positive because I don't have any documentation to back it up but I would think GM took the port design as well as intake manifold design into account when trying to achieve complete combustion. Do you agree? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 20, 2009 Share Posted March 20, 2009 Yeah the chamber shape is similar but the ports are extremely different which I think will have a huge effect on swirl. I'm not positive because I don't have any documentation to back it up but I would think GM took the port design as well as intake manifold design into account when trying to achieve complete combustion. Do you agree? Not sure. It could be that you're right, but my instinct is no. The only high swirl ports I've had close contact with are Toyota 22RE ports, and they actually have a curve right at the end so as to send the charge into the cylinder already spinning (it's a shitty design by the way). The LS1 ports from what I've seen just go straight in. There may be some method of swirling the intake that I'm not aware of and I'd certainly go ahead and say that the LS ports have superior flow rates, but I don't see anything in there with regards to getting the charge to swirl. Quote Link to comment Share on other sites More sharing options...
Careless Posted March 20, 2009 Share Posted March 20, 2009 There was a guy who had a couple of tests done on some cylinder heads and engines using various professional equipment with real running cars that said the temperature and idle rpm dropped considerably, but the horsepower figures were not as high. we're talking about +/- 5 to 10% for both idle speed/rpm and horsepower, both opposite of eachother. THERE IS A PDF floating around somewhere. I don't see the use for them. The hard edges would mostly cause hot spots in the combustion chambers and start to detonate if you were using it for autocrossing or road courses. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 20, 2009 Share Posted March 20, 2009 I don't see the use for them. The hard edges would mostly cause hot spots in the combustion chambers and start to detonate if you were using it for autocrossing or road courses. So hit the edge with a little sandpaper. The edge doesn't need to be sharp for the groove to work. The question is does the groove work? If it doesn't then that's that. Quote Link to comment Share on other sites More sharing options...
johnc Posted March 20, 2009 Share Posted March 20, 2009 I think the grooves do induce some kind of turbulence in the combustion chamber. So what? If you take a properly tuned and optimized engine and cut grooves in the combustion chamber, how will that increase horsepower? Probably not because you've reduced the compression ratio. If you take a poorly tuned and non-optimized engine and cut grooves in the combustion chamber, how will that increase horsepower? Probably so by inducing enough extra turbulence to burn a little more of the fuel that isn't getting burned before the grooves were cut. So, if you've got a poor running car, pull the head and cut grooves in the combustion chamber! Quote Link to comment Share on other sites More sharing options...
rags Posted March 20, 2009 Share Posted March 20, 2009 So, if you've got a poor running car, pull the head and cut grooves in the combustion chamber! That's why my signature says "wanna be tuner". I have no idea what I'm doing so I'm looking for a shortcut! Quote Link to comment Share on other sites More sharing options...
Raami Posted March 20, 2009 Share Posted March 20, 2009 I think those grooves might help if you have P90-head style chambers and dished pistons, then the flame could travel easier. Or not. I was just thinking and as usual I might be wrong. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted March 20, 2009 Share Posted March 20, 2009 I think the grooves do induce some kind of turbulence in the combustion chamber. So what? So that might lead to decreased detonation just the same way that good quench does. Does good quench + grooves make it even more detonation resistant? Maybe. Is it worth looking at? Sure! Why the hell not? If you take a properly tuned and optimized engine and cut grooves in the combustion chamber, how will that increase horsepower? Probably not because you've reduced the compression ratio. You can always up the compression ratio. That's not a tough one to figure out. How to make an engine detonation resistant... that's a tougher nut to crack. How will detonation resistance improve power? Well it would potentially free up more timing adjustments, we know there is power there. It might also enable an engine to use a lower octane fuel, we know there is power there also. It's not too hard to see how it COULD be possible. Whether it is or not still takes some testing to figure out. I think those grooves might help if you have P90-head style chambers and dished pistons, then the flame could travel easier. Or not. I was just thinking and as usual I might be wrong. I don't think the grooves do anything at all with dished pistons. the point is that you get a jet of air out of the groove when the piston comes up close to the head. If they never get close, no jet of air, it does nothing. Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted March 20, 2009 Share Posted March 20, 2009 My BMW R60/5 is notorious for pinging... maybe after its ready to ride Ill try it. They dual plug these motors because the design sucks. Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted March 21, 2009 Author Share Posted March 21, 2009 You can always up the compression ratio. That's not a tough one to figure out. How to make an engine detonation resistant... that's a tougher nut to crack. How will detonation resistance improve power? Well it would potentially free up more timing adjustments, we know there is power there. It might also enable an engine to use a lower octane fuel, we know there is power there also. It's not too hard to see how it COULD be possible. Whether it is or not still takes some testing to figure out. I think atleast on our L series engines the biggest gains are going to be people running turbos who can turn up the boost, atleast untill people start building NA engines specifically with the grooves in mind (assuming that testing shows that they work). Quote Link to comment Share on other sites More sharing options...
caen fred Posted March 21, 2009 Share Posted March 21, 2009 I will try it on my L28 Flat pistons with a MN47... and FI Honestly, I don't thing there is anything to loose, one CC less is in fact better on this combo. I will take the car to a dyno soon to tune up my new FI, I will let you know all the figures Funny the one thing that I am concerned is not mentioned anywhere! Cracking the head from the groove... I have seen L serie heads cracked before at the port. I guess we have plenty of "meat" in the flat area where the groove goes? Quote Link to comment Share on other sites More sharing options...
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