Squish band

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Sure, I've done a lot of research Jaguar. What do you take me for? I manufacture cylinder heads and other kinds of performance enhancing parts for these engines. I certainly don't do this stuff blindly.

I have spent countless hours building and testing these designs, compared with other designs, etc. When I first started out running these kind of engines, I ran into terrible problems with detonation and overheating.

If you are putting around at 30 MPH it's probably OK to run stock equipment.

I started making these cylinder heads because they were necessary in order to do what I wanted to do, which is to travel 40-50+ MPH.

I have read that book from Jennings. It's very good. If you too have read that book, and understood it, certainly you would have seen then the importance of the squish band.
You know, it probably does create more mixing of air/fuel mixture, well, the more the better!

I have made and tested a lot of prototypes. I don't think you have. You shouldn't talk like you are an expert about something unless you really are.

Large manufacturers guided by proven racing results, who have tried everything under the sun make squish band combustion chamber cylinder heads for small engines.
This is for a very good reason, because they allow you to run higher compression without the damaging effects of detonation. My god, this is basic stuff here!

They would never support what you are saying about combustion chambers. You tests were just weak or flawed, or you don't have the capabilities to test different designs.
You know, you would have to make different cylinder heads to do this. Have you done that? I get the feeling that you don't have the capability to do this.

I have done this type of research, and you are quite wrong here. I saw some You tube video a while back promoting your Jag ignition box, and it was pathetic!

That pretty model was revving that sad little engine with a scared look on her face, like, "who is this guy that put me up to this."

All stock, revving so lamely. Gosh, it was sad. There was no punch there.

Make an engine and race against a competent racing team and see what happens. If you would like me to continue, I can talk about why using a ignition retard module is a compromise solution to the quest of better performance.
-Fred
 
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ok Freddy here goes
thanks for all the insults. It lets me know what a moral-less person you are.
Yes I did make my own head with squish band by modifying a stock 55cc head.
What I have presented is reasons in favor of the argument that a squish band is not helpful for an engine with no more than 130psi and that revs under 9000. You havent presented anything in your defense. That is why you have to insult, because you have no substance. You keep talking about race eninges and for them, of course, it is necessary. And yes heads with squish bands are on most small engines but those engines are much much closer to being a competition engine than a putt-putt Grubee engine. They have much more compression and they rev much higher.
If your heads bring the compression over 130psi then its cool that it has a squish band. I have no problem with that. I just hope you warn your customers to also change the upper conrod bearing and to be aware that the lower conrod bearing will now have a much shorter lifespan.
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in my mind, what i know of squish bands and such forth, is that, on the zbox happytime grubee call it what you will, the piston has a fairly large chamfer on it. well, 48s do at least. (just double checked...the 66 has a slight dome but no chamfer)

just the chamfer alone nullifies any effect generated by the squish band by holding quite a large volume of unburnt, cold, and seperated charge mixture...

unless you was to skim cylinder down to edge of chamfer plus clearance, then shape head to suit.


im getting sick of this CC stuff. 48, 50, 55, 60, 66, 70, 80... arrrrrgh!
 
Whatever Jaguar. You talk about mods for more performance, then say that squish band type cylinder heads are not important. What?

Well, they are important and very helpful for real performance benefit for street and racing. That's what racing competition does, it improves design for everybody, allowing higher performance.

You are talking about higher performance aren't you? Now you are back pedaling, trying to make it seem that the racing scene is a completely far off practice. Well, it's not.

Lots of people on the street want better performance, and what you are saying about combustion chambers is totally wrong.

You just don't know what you are talking about. Showing us some boring graph like it's supposed to impress us. Just go away!

Like, you are right and everybody else is wrong. I don't think so. Look at all the competition combustion chambers. You think that's not important? Well, it is important.

Either you are into performance, or you are not.

It's okay that you are happy putting along at 30 MPH with your overheating stock setup, but don't go running your mouth, talking a bunch of lame nonsense that squish band combustion chambers don't help improve performance for small 2 stroke engines.
-Fred
 
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I still just hear a lot of wind with no real substance.
I have given technical reasons and real life experience to back up what I am saying. You just keep on defending race engines. Yeah I am in to performance but since these are usually one speed rides I dont recommend porting them for anything higher than 8000 rpm. And I dont recommend any higher compression than 130 psi, both of which brings the engine into the category of not needing a squish band. But if someone wants 150 psi then I am all for a high compression head with a squish band. That is where machinists like you come in. My initial post was strictly concerning squish bands, not high compression heads with squish bands. So there was never any reason for you to march to war and catapult all the insults you could think of at me. I dont need to insult you back since you are doing a real good job of making yourself look bad.
Who has got my back is Gordon Jennings himself. He said basically that only a race engine with more than a 6.5:1 compression ratio is in need of a squish band. I rest my case.
 
I have purchased CR Machine Manufacturing cylinder heads in both the 2 hole and 3 hole versions. I have also purchased CR Machine Manufacturing modified OEM pistons.

I have been happy with the results but what i am most happy with is the dramatically improved cooling surfaces with the CR Machine Manufacturing cylinder heads. They have a massive heat sink area compared to other billet cylinder heads that i have tried, enabling an 80 degree (Celsius) drop in peak cylinder head temperature compared to other billet cylinder heads.

If i had three thumbs, i would give CR Machine Manufacturing a full three thumbs up for his cylinder heads.
 
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Jaguar. No substance? You are not reading and comprehending what I am saying then.

I have written about my testing. I put a 1/4 Inch size hole in a piston because of detonation related overheating while running a stock head.

Since I have started making my squish band heads, those engine problems have completely gone away.

You are arguing with a manufacturer who naturally has a need to do comprehensive testing.

You are saying that I am not giving any substance? What do you think I've been writing about?

Partial detonation occurs with these engines. Your engine partially detonates, I guarantee it. And, according to Jennings, you can't tell by listening to the engine.

The engine problems I had before I started making squish band type heads was frequent.

After making the first prototype head with a 6.2 cc combustion chamber (a significant compression increase), compared to the stock 7.2 cc combustion chamber, the engine ran cooler, and I wasn't having frequent bearing failures and piston and cylinder damage.

I attributed this to the detonation management that a squish band provides for a combustion chamber.

I make low compression heads which have the same compression as the stock heads as well. In fact, that is what I'm running in one of my test bikes which uses low octane fuel.

I don't believe that Jennings would agree with you. I also don't agree with those compression ratio numbers you have cooked up.

Jaguar, I've noticed that you like to fluff up a lot of your theories with a bunch of wordy mumbo jumbo and graphs. That's what a BSer does.

Take note of what Fabian said: Honda uses that same technology, Honda. So, you are going to argue with Honda? Well then, you are coo-coo!
-Fred
 
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Someone once said that if Honda has researched and developed an engine design or theory, there is no point in trying to reinvent the wheel over a company that spends 500 million dollars per year on piston engine development.

Honda only stops development on a particular technology when it has been refined to the point where further development yields no benefits.
 
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