915 Heads On 383

[RustyRatRod]

And the Ford Duratec head. I circled the quench pad in case you can't figure it out. It's always the pad opposite the exhaust valves to help generate a "push" towards the exhaust side. For the record, both that Nissan engine and the Duratec are still being made. Modern quench multi valve technology. You should do more reading and learning and less arguing. I hope you know more about drive shafts.....but honestly, I know where I WON'T be takin my driveline business. lol

 

[RustyRatRod]

Here's the Duratec piston. And hay, even I learned somethin new. It's got quench pads on BOTH sides. Imagine that. Ford knew the value of quench so much, that they made a double quench motor. Pretty cool really. Now keep arguin, you're makin me look smart.

 

[RustyRatRod]

Good article, Crankamous, thanks for the link. Yeah, people are scared of new stuff. Stuff they've never tried and have little to no experience doin. Like you, I've built a few quench motors. My last was a stock stroke 12:1 iron head 360. While I DID have to retard the timing 4* for pump premium, it did run on it. It loved the 114 at the track, though. lol Even so, I still call the quench stuff "new" to me, as I am still learning. This 383 is gonna be a good one though, I think. I just got my pistons comin today. ;)

With 'good' quench, you can actually run higher compression ratios and use pump gas. Do a search on quench and you should find an article on it by Keith Black Pistons which was reposted with permission from:

By John Erb
Chief Engineer
KB Performance Pistons

Edit, I found it for ya....yeah, I posted it but it's for the good of the Mopar hobby etc. You can do your own research on the subject if you don't like what I post.....

http://www.forbbodiesonly.com/moparforum/showthread.php?t=12581&highlight=quench

 

[fatecaptured]

You should make a thread on your 383 build rusty, so i can copy it when I do decide to build my spare 383

 

[RustyRatRod]

You should make a thread on your 383 build rusty, so i can copy it when I do decide to build my spare 383

I will. I just got my pistons comin today. Probably be here Monday. Tryin to get ahold of a member here for some rods. Caint get him to answer me, so he may just miss out on that sale. Then I'd have the whole short block pretty much. Already have the 516 heads (thanks Bob!) but they need reworkin. I'm gettin there.

 

[Supershafts]

And the Ford Duratec head. I circled the quench pad in case you can't figure it out. It's always the pad opposite the exhaust valves to help generate a "push" towards the exhaust side. For the record, both that Nissan engine and the Duratec are still being made. Modern quench multi valve technology. You should do more reading and learning and less arguing. I hope you know more about drive shafts.....but honestly, I know where I WON'T be takin my driveline business. lol

You really aren't so great on the topic as you think you really are.

1st if you had a clue you would know that 4v heads don't really rely on quench or swirl but do really on velocity, squish and TUMBLE, tumble swirl is used as the charge comes in to the opposing cyl wall and then reverse tumble across the piston face and be forced to the center of the chamber still in tumble.
They DO NOT use quench as you so want to believe they do, since the small pad on each side concentrates the area across the center as squish and not quench, and not to the exhaust valve like you so want to believe, it is a small concentration to the center and not at the plug, the piston forces the charge to center of the head , quench in a multivalve could cause turbulence and hurt the fire since it will blow across it and is no where near the same as in a 2 valve wedge design where it concentrates the turbulence to the chamber and at the plug and pulling heat as quench, in a multi valve head it simply makes a little turbulence but it does not act as quench since it can not direct its force to the center of the head and defined spot in the chamber.

Don't worry about coming to me, i wouldn't want to make you actually go fast. It's always more fun to know nothing and be faster then the guy to talk about fast but really know nothing.

.

 

[daredevil]

Some good info flowing in this thread but I got to admit as a mod ya,ll are making me a little nervous. Would be happy to see ya,ll refrain from name calling if at all possible. thanks for your cooperation.

 

[Supershafts]

Here's the Duratec piston. And hay, even I learned somethin new. It's got quench pads on BOTH sides. Imagine that. Ford knew the value of quench so much, that they made a double quench motor. Pretty cool really. Now keep arguin, you're makin me look smart.

lmfao, you keep highlighting squish areas.... You have no idea why the piston has the raised circular design in center and you claim to understand quench.... You have no idea what quench and squish are, you most definitely believe the 2 are the same.


Really, you think you look smart here, this isn't making you look smart.
You understand that quench is the end part of the cycle and that quench is the cooler in which what prevents detonation, of which there is very little squish at the outside, just like a dish piston only has slight squish.

 

[Supershafts]

Some good info flowing in this thread but I got to admit as a mod ya,ll are making me a little nervous. Would be happy to see ya,ll refrain from name calling if at all possible. thanks for your cooperation.

I don't understand why they do that, it simply makes people just not bother to explain anything and only hurts the people that could really better understand something.

 

[Cranky]

Hey Supershafts....how bout explaining the difference between squish and quench is. I thought I posted a link to what that was and how it works. The article was written by John Erb and anyone that knows who he is knows he's no dummy.

Rusty, the most compression I've ever built for pump gas was 11.6-1 using a stock rod 360 flat top motor. It too ran a little better number on race gas vs 92 pump....

 

[Supershafts]

I'll wait for your professor first then after he completes his thesis of not knowing the difference between squish and quench i'll explain it best i can.

So far all the professor of slow has shown is squish points, and that is not quench, quench is what happens AFTER the plug and ignition has occurred, he has no clue so even with that much i'll wait for the professor of slow to explain something he believes is related to what happens in the chamber and then i'll do it best i can.

 

[Cranky]

I'll wait for your professor first then after he completes his thesis of not knowing the difference between squish and quench i'll explain it best i can.

So far all the professor of slow has shown is squish points, and that is not quench, quench is what happens AFTER the plug and ignition has occurred, he has no clue so even with that much i'll wait for the professor of slow to explain something he believes is related to what happens in the chamber and then i'll do it best i can.

:confused5:

 

[fatecaptured]

This is interesting and it would be even more so if the grudge match wasn't going on. I myself am more interested in the facts of a best performer(engine combo) and not smarter person. Yall know more than me so cudos to all parties...

 

[RustyRatRod]

Some good info flowing in this thread but I got to admit as a mod ya,ll are making me a little nervous. Would be happy to see ya,ll refrain from name calling if at all possible. thanks for your cooperation.

You got it buddy.

 

[Cranky]

Well, there really isn't any difference between a 'squish' area vs 'quench' area. They are both the same but many call the quench area a squish area. What does quench really do? According to Mr. Erb, "it kicks the burning flame front across and around the cylinder at exactly TDC in all cylinders," and yes, that's happens right after the plug fires. And btw, Rusty isn't 'my' professor.

 

[RustyRatRod]

This is interesting and it would be even more so if the grudge match wasn't going on. I myself am more interested in the facts of a best performer(engine combo) and not smarter person. Yall know more than me so cudos to all parties...

I agree. I could have gone without usin all of the snarkyness, I guess. All I did do was point out quench pads on cylinder heads and on pistons. It's up to everybody else to believe what they are....or not. I mean really, a blind man can see the quench pads on that Escape piston. What more does it take? Quench was a good thing back in the 50s and 60s. All manufacturers did was refine and tune it, just like everything else. I'm no expert on quench as it's new to me too......however, I've done enough reading and asking those in the know that I can recognize a purpose built quench engine when I see one. Those two modern examples I posted are quench engines.

Ok, this is it for me on this. I'm sorry for all the arguing. All I originally was trying to do was learn something and add to. Sorry it turned into a piss fest. But look guys. Don't take my word for it. Do your own research like I have. A quench motor doesn't have to be an old school 2 valve closed chambered headed motor. It can be any kinda engine you want it to be as long as all the right elements are there.

 

[Cranky]

I've been trying to study the new technologies in engine design for a long time, quench/squish, swirl, turbulence, and the list goes on. It can make your head spin....well, it maked mine spin lol. Let's face the fact that our old engines are...well, old and the technology isn't exactly up to date but with the right choice of parts, they can be made to run better than they did in the day when gas was better than today.

IMO,one of the screwups that 'mom' made was lowering compression using dished or flat top pistons and using open chambered heads. The consensus back then was to lower NOX pollutants and lowering compression was supposed to lower cylinder temps which in turn lowers NOX. It didn't work very well. Cylinder temps usually went higher because of lousy combustion chamber design coupled with low compression and absolutely no quench which generally caused bad detonation. The combination just wasn't conducive to quality combustion. Then to top that off, we had dieseling when the ignition was shut off. Anyone here remember the smogger engines of the mid to late 70's? I sure do. Speaking of dieseling, there were many out there that would continue to diesel for as long as you let them and the only way to stop it was to stick it in gear. Well now a days, you don't see that design much anymore and I'm glad of that!

If you ever build an engine, do your homework and research it out. As for the quench distance, I will never build another street engine with more than .035 clearance and will do my best to keep it closer to .030. IMO, the .040-.045 figure has become old school and is merely a 'safe' number and I think I understand why most shops use it. A lot of people still like to build engines with a ton of piston clearance and well if you do that, then you will need more quench distance but with minimum piston clearances, you can shoot for thighter QD's.

 

[fatecaptured]

I agree. I could have gone without usin all of the snarkyness, I guess. All I did do was point out quench pads on cylinder heads and on pistons. It's up to everybody else to believe what they are....or not. I mean really, a blind man can see the quench pads on that Escape piston. What more does it take? Quench was a good thing back in the 50s and 60s. All manufacturers did was refine and tune it, just like everything else. I'm no expert on quench as it's new to me too......however, I've done enough reading and asking those in the know that I can recognize a purpose built quench engine when I see one. Those two modern examples I posted are quench engines.

Ok, this is it for me on this. I'm sorry for all the arguing. All I originally was trying to do was learn something and add to. Sorry it turned into a piss fest. But look guys. Don't take my word for it. Do your own research like I have. A quench motor doesn't have to be an old school 2 valve closed chambered headed motor. It can be any kinda engine you want it to be as long as all the right elements are there.

**** happens. Was more or less talking about the "professor" comment.

 

[Supershafts]

Quench is to cool, quench is the ability to lower the temp and prevent detonation and move the initial event to happen closer to td than before it creating more torque by not wasting it as a lost explosion btd. The more timing, the worse the burn, the less effect of quench the loss of power and more chance of detonation

Squish is the area between the piston and flat surfaces of the head, and that is squish, squish is a turbulence to better mix or swirl or swirl and tumble to create a better more complete mix which burns more efficient and clean. quench is the effect of pushing the mix into the flame front and not allow it to burn at the back end but explode by feeding it at the front which reduces timing and builds more torque and lowers exhaust temp since the complete burn is now a explosion in one exact time across the pistons entire face or crown and not to the side, or in one area of the piston and chamber but uniform on the piston and chamber.
Squish is in all motors, some have bigger areas of squish and others have minimal amount of squish, quench is the design of directing or feeding the squish in one direction to cool or slow the burn, the examples another has put up is just squish, there is no directing to quench it it is simply squish, squish doesn't make quench it makes turbulence.

 

[Supershafts]

I will never build another street engine with more than .035 clearance and will do my best to keep it closer to .030. IMO, the .040-.045 figure has become old school and is merely a 'safe' number and I think I understand why most shops use it. A lot of people still like to build engines with a ton of piston clearance and well if you do that, then you will need more quench distance but with minimum piston clearances, you can shoot for thighter QD's.

A street motor can benefit from .04, and taking piston speed into effect you can adjust that further and then you need to figure in the P to W clearance to further adjust that and comp ratio, the end of the squish area is also the start of the quench feed area, maybe that will make the understanding and make the defining area of squish and quench easier understood.
Now this is also why the old school idea of the long rod and big RR is bad, it can and does aid in this area negatively and the piston speed of area of use is important to the motors area of use and the RR should be adjusted to that area of use, not saying you have to, but if you want the best of everything to work together in that area of use you should adjust it all together.
Then when the ability to make that change cheaply arrises when sticking a 440 crank in a 400 or 383 you throw the dopey 440 length rod and ma mopar knew better with the big RR ANCIENT school thinking away as that will also aid in the quench working better in the street motor.