To Quench or Not to Quench?

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VIOLENT\6

VIOLENT\6

12 second N/A Slant 6?
Joined
Mar 31, 2007
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Location
Massena, NY...Almost Cana
If I run 89mm 2.2L Turbo pistons W/-18cc voluume on 7.005" Molnar rods,


reduce the head deck by .110", have the combustion chamber perimeter cut to allow the piston crown to enter the chamber & run the pistons at +.070" positive deck W/a .035" head gasket, I can achieve .055" quench height at about 12.8:1 CR. A small amount of offset grind on the crank and/or some block decking work may be needed to get to those specs depending on the existing deck height.

This will make pump gas a bit low on octane so either additives or water methanol injection will be required & nitrous will be out of the question.

The other alternative would be to run .000" deck on the pistons W/10.5:1 CR.

That would allow using 93 octane pump gas & have a 125 shot of nitrous on tap just for giggles.

What say ye Slant 6 gurus?

Would 12.3:1 be feasable W/the right cam to bleed off chamber pressure at lower RPM to allow 93 octane fuel?

Will mechanical octane (quench) make enough difference to allow 93 octane pump gas use?

Would the HP difference between 12.8 & 10.5 be enough to not have the nitrous option. I know that the lower CR engine on juice would blow away the high CR engine, but compairing both in N/A form, what would the power difference be?

Would the 12.8:1 CR make my 12.99 N/A goal a little easier to reach?
 
I do not know, but please keep asking your questions. I am not knowledgeable enough to even ask these questions, but I'm learning a lot reading the responses.
 
I know that they say quench is out of the question W/a slant 6, but my undertsanding is that a quech height of between .065" & .035" is acceptable. The minimal .035" would be applicable only to automatic cars when steel rods are employed.

That being the case, unless my calculations are wrong it is possible albeit at rather high CR.

deck = 10.68
rod = 7.005
piston= 1.594
diff, = 2.081

2.081x2=4.162

4.125 + .050 (.025 offset grind X 2)= 4.175 stroke = .007" + deck

.070 -.007 = .063 block deck reduction for .070" + deck piston crown.


Head: .200" to quench pads on stock (late model) head. .110" deck reduction yields:

.200 - .110 = .090" - .070 = .020 + .035 head gasket = .055" quench height.

.110 deck reduction = 44cc chamber add 1cc for perimeter cut for piston crown clearance.

45cc at .090" quench. Reduce qunch by .045 = approx 7cc (1cc per .006")

45cc - 7cc = 38cc + 18cc for piston dish = 56cc

Swept volume at 4.175 stroke by 3.504 bore = 40.24 cu in = 659.7cc + 56cc = 715.7 cc total cylinder/combustrion chanber voluume/56 = 12.8:1 CR.

Increase quench by .012 to reduce compression but stay whithin .065" (.062") to increase combustion chamber voluume to 58cc.

659.7 + 58 = 717.7/58 = 12.4:1 CR

Lets go the other way.

Reduce quench height to .035" will reduce the combustion chamber voluum by 3cc.

659.7 + 53cc = 712.7/53 = 13.5 CR

So, there you have it. A slant 6 engine can be built W/off the shelf components to achieve accepted quench heights but CR will be between 12.4:1 & 13.5:1.

Now, this is my 1st rodeo W/the Slant 6. (but not stroker engines) Are my calculation/assumptions correct?

Let's hear from you Slant 6 gurus.

This may not have been done before, but as long as the 93 octane factor can be worked around, I see no reason why it wouldn't work.
 
Why not get with Doug Dutra and see if he has or knows where another Argentine closed chamber head is? I say go with quench if you can, sure, but to get a stock slant head to be quench I think would be a costly proposition. Gettin into some of that "exotic" you talked about. The stock heads are just not made for it.
 
RustyRatRod said:
Why not get with Doug Dutra and see if he has or knows where another Argentine closed chamber head is? I say go with quench if you can, sure, but to get a stock slant head to be quench I think would be a costly proposition. Gettin into some of that "exotic" you talked about. The stock heads are just not made for it.
Click to expand...

I don't think it would be difficult at all.

Compare these PIX.

The 1st is of a \6 head that has had a severe head deck reduction.


Now. compare the stock late model combustion chamber.


Rather than going the 1st route, which would, IMO render a severely thinned head deck, doing a moderate .110" deck reduction on the stock head followed by a 3.500" perimeter cut (required to allow the + deck piston) could be used to make a uniform quench pad around the combustion chamber.

I don't think we are getting into anthing that the average (competant) automotive machine shop could not accomplish.

Not what I consider "exotic".

Out of the box perhaps, but nothing extraordinary.
 
I get what you're sayin. And when you posted the pics, I can certainly see where you may be able to get quench......but I'm tellin you, between the two heads you have pictured, the one that's not been milled is the best. Not saying you cannot make the milled one good. I am just telling you what Doug Dutra has said. If you visit slant six.org, look around. There are a lot of tech articles over there. The reason the later head is better has something to do with the filled in area under the plug. It gives sorta a "swirl" effect. At least that's my understanding. I'm interested to see what you come up with. I think anything would be an improvement over stock.

Oh and just so you know, you and your slant buildin woke me up. I went out in the shop and disassembled my bwoowack rockers yesterday and put them in the cleaner. I'm gonna call Gary myself and see what I can work out. Thanks. lol
 
The concept would be similar to the Gen III pre '09 5.7 hemi.

When the head deck is reduced by .030" it leaves a .015" negative deck quench pad.

Stock pre '09 5.7 pistons have a +.008" domed piston.

When the stock .028" head gasket is employed, it leaves .035" quench.

It doesn't matter how this is acheived, as long as the deck specifications add up.
Just imagine the perimeter of the combustion chamber machined to 3.500" diameter @ a depth of .090".

The piston will come into that area & extend above the compressed head gasket by .035".

Take .035" from .090" & you have a gap of .055".

Viola, acceptable quench distance in a slighly modified stockish combustion chamber.

How much would boring six .090" deep holes into the head deck cost?
 
Trust me, I understand quench. I have all my parts ready and machined to build a 10.4:1 383 with domed pistons and closed chamber heads. Yup. A quench dome motor. Most people shudder when I say that, but the KB400 pistons are designed as quench dome pistons.

Good luck. Keep us posted.
 
....and I'll add this for food for thought. Ed talks about the 1" lifter thing.....which is a really cool idea and all, but nothin new. Mushroom lifters have been around a LONG time and serve the same purpose. To have more surface area for a more aggressive cam lobe. I am certain since the lifter diameter is .903, like other Chryslers, the slant could accept a mushroom lifter. I know Oregon could grind a mushroom cam. That would probably be more cost effective than the 1" lifter thing. Just a thought.
 
RustyRatRod said:
I get what you're sayin. And when you posted the pics, I can certainly see where you may be able to get quench......but I'm tellin you, between the two heads you have pictured, the one that's not been milled is the best.
Click to expand...

I agree 100% The excessively milled head is nothing more than an unwieldy boat anchor IMO.


RustyRatRod said:
The reason the later head is better has something to do with the filled in area under the plug. It gives sorta a "swirl" effect. At least that's my understanding. I'm interested to see what you come up with. I think anything would be an improvement over stock.
Click to expand...

The "filled in area uder the plug" as well as the flat spot on the opposite side are the reason that I think that by counterboring the deck to reach these area W/a 3.510" diameter recess will achieve what I am looking for. By bringing the piston crown closer to that "filled in area" I will increase the "swirl" affect. That is what quench is all about.

The only thing different about all this is that it will rely on the piston coming out of the block by a bit more than what is usual. I will have to make sure that the ring gap is ample on the top ring as it will be coming awfully close to the top of the bore & the resutant hot combustion gases. All of this "quench" will be occuring quite some distance above either the block or head deck.

The same thing could be accomplished by filling in the area W/weld before the deck is milled. That might technically be the better route, but it would be expensive.



RustyRatRod said:
Oh and just so you know, you and your slant buildin woke me up. I went out in the shop and disassembled my bwoowack rockers yesterday and put them in the cleaner. I'm gonna call Gary myself and see what I can work out. Thanks. lol
Click to expand...

For the life of me I could not understand why you hadn't already done that.:scratch:
 
Tons of things. The past few years have sucked balls for me. I'm disabled. I have severe depression, I am up and down. Most of the time I don't feel like doing anything.
 
RustyRatRod said:
....and I'll add this for food for thought. Ed talks about the 1" lifter thing.....which is a really cool idea and all, but nothin new. Mushroom lifters have been around a LONG time and serve the same purpose. To have more surface area for a more aggressive cam lobe. I am certain since the lifter diameter is .903, like other Chryslers, the slant could accept a mushroom lifter. I know Oregon could grind a mushroom cam. That would probably be more cost effective than the 1" lifter thing. Just a thought.
Click to expand...

Only problem I see W/mushroom lifters is that they have to be inserted before the cam & if you ever have problems they can't be removed W/O a complete teardown.

I'll opt for the small added expense of enlarging the lifter bores.

So here's how the rotating asembly stacks up.

12-13:1 CR rotating assembly consisting of 89mm 2.2L KB168 turbo pistons W/-18cc dish running +.070"ish positive deck on 7.005" Molnar rods on a .025" offset ground stock crank (4.175" stroke)

Block will be decked/squared to acieve a satifactory quench distance, somehwere in the .070" area. Block will be prepped for 1" lifters.

Heads will have the deck counterbored @ a nominal bore diameter to a depth that will clean up the quench pads that already exist. The rest of the chambers will be left as is except for a polish to eliminate any potential hot spots. Valves sizes & port geometry to be determined but if possible, small stem diameter valves will have tulip shaped heads to add to the already cramped combustion chamber voluume.

The head deck will be reduced about .110" to achive the desired quench distance values.

Buick straight 8 rockers will be utilized for 1.6 rocker arm ratio.

Cam, valves, ports, induction, exhuast will be sec'ed to maximize TQ in the 3000-5500 RPM range W/peak HP around 5000 RPM carring to 5500 RPM W/O a rapid drop off.

Hopefully CR can be dropped somehow to a level that will allow 93 octane pump gas to be used. If not, perhaps water methanol injection will be employed.

If WM is employed, CR will be kept higher, perhaps as high as 13.5:1.

3000 RPM stal on 4.10 gears W/28" drag radials 2800# wet W/driver.
 
Preach on brother. I wanna see this one slung together.
 
RustyRatRod said:
Tons of things. The past few years have sucked balls for me. I'm disabled. I have severe depression, I am up and down. Most of the time I don't feel like doing anything.
Click to expand...

Been there, done that.

I have been out of work since June of '09 when GM closed the plant here & wouldn't allow transfers as skilled trades.

I started suffering from moderate depression last summer & soon thereafter my knees locked up when I quit riding my bicycle regularly. I had my right knee totally replaced on Dec 10 of '12 & the left on March 25 of this year.

I sold off all the mods on my '06 Charger ($12K worth for $7K) & refinanced the Charger to keep the mortgage paid.

For the last year I have been Hotrodding Saito Hemi head 4-stroke model aircraft engines because it was cheaper than doing cars.

Here are some links:
http://www.rcgroups.com/forums/showthread.php?t=1754616

http://www.rcgroups.com/forums/showthread.php?t=1769449

My Social Security kicked in in December so my financial situation has improved enough that I can afford to get to work on my '65 Valiant.

As soon as I recover from the last total knee replacement in a few months I can find part time work to earn play $$.

Hang in there.
 
Now you're scaring me. My knees are giving me fits lately.
 
RustyRatRod said:
Preach on brother. I wanna see this one slung together.
Click to expand...

1st things 1st.

I have to find a disc brake conversion off of a later model Mopar & an 8 3/4" diff to get the car rolling on BBP 5 X 4 1/2 wheels W/decent rubber & good brakes.

Probably the 1st thing on the engine will be the Buick rockers. I am trying to get some shipped direct to Gary.

Then, I need to find a late model head so I can start machining/checking to see if this will even work.

1st order would be to conterbore the deck using a big bore head gasket as a guide.

If I can get them cheap enough, might even buy 2 similar vintage late model heads so I can section 1 of them to see what kind of material thickness I am dealing with in the combustion chamber area.

This is just the type of thing a man needs to get him up off off his A$$ to start doing something.
 
More food for thought on the brakes. The FMJ cars make nice donors. I am putting 87 Fury discs on my little 63 Dart. Direct bolt on, with the right upper control arms, believe it or not.
 
RustyRatRod said:
More food for thought on the brakes. The FMJ cars make nice donors. I am putting 87 Fury discs on my little 63 Dart. Direct bolt on, with the right upper control arms, believe it or not.
Click to expand...

Do you mean the "correct" upper control arm of the starboard (right) upper control arm? :scratch:
 
Yes. Sorry. The correct upper arm. lol That would be for instance 73 and up A body disc brake arms.

...and all this slant six blabber got me motivated. I went out and pulled my super six down to the short block. It's a standard bore cast crank engine....so it's an original super six. They were all cast crank motors. Fine with me because the cast crank is actually lighter. lol I certainly will never push its limits in a rat rod. I may get the rest torn down later this afternoon. Gotta rest a little first.
 
RustyRatRod said:
Yes. Sorry. The correct upper arm. lol That would be for instance 73 and up A body disc brake arms.

...and all this slant six blabber got me motivated. I went out and pulled my super six down to the short block. It's a standard bore cast crank engine....so it's an original super six. They were all cast crank motors. Fine with me because the cast crank is actually lighter. lol I certainly will never push its limits in a rat rod. I may get the rest torn down later this afternoon. Gotta rest a little first.
Click to expand...

Hey glad I could be a motivational inspiration!

I showed my son the Buick rockers & he thought that was cool. I originally bought the car for him, but he was mistreating it & decided he wanted a P/U (which he proceeded to detroy) so I took possession of the car a colateral for a loan on which he ended up defaulting. That was back in 2011.

Now he just bought a '97 Corolla W/his own money & after walking for almost 2 years he has a much better perspective. He wants to help me work on the car as long as he can drive it occasionally & after all, when I'm gone, or too old to drive, it will be his anyway.

Do you know where I might find some (cheap) 198 rods?

The prices I'm seeing for them are so high that by the time I get good rod bolts in them & have the big ends honed, I'd have as much in them as a set of the Molnars.

I'm not opposed to using 198 rods.

This engine won't be twisting above 5500 RPM @ the most & even then only for a few seconds.

Buying the OEM rods now & reconditioning them would be the type of low $$$ impact thing I'm looking for @ the present.
 
I'll keep my eyes peeled.
 
Well you said you were looking for more input on the water meth so here's what I can tell you.

With the higher compression ratio and increased quench, of course you will see a gain in horsepower. Not and incredible increase like say, bigger valves. The biggest gain you will see is in throttle response and your engine will seem very peppy like a playful kitten.

Now once again, just compression bump alone wil help moderately with power. The water methanol injection will give you a one-two punch. Because you will be able to increase compression first off. Secondly, water methanol injection lowers the temperature of the intake charge for obvious reasons and it will also help the motor run cooler becaue of the evaporative action of the water. Here's where water methanol injection alone will build power, what happens to water when it boils? You get high pressure steam! That alone will also give you an increase in horsepower.

This is the snow performance kit I would reccomend for you car. I've heard lots of great reviews on snow. http://www.snowperformance.net/stage-2-boost-cooler-muscle-car-n-a.html

The kit advertises you can use pump gas on a 10:1-14.5:1 CR ratio and I believe that the large coverage there is due to cam selection. Stock cams will detonate with this kit closer to 10:1 and wild one will be covered closer to 14.5:1.

Have you chosen a camshaft yet? The whole pump gas / water meth BS we are throwing around is just that, BS, if we don't have a DCR yet. What I would do if I were you is contact snow, and ask if they know what kind of DCR their kit will cover. If they don't know, find another company with kits that are either universal or specific to N/A carb builds and ask them.

The water methanol kits will help save alot of money on the long run, especially in a street strip car. Premium fuel in my area is a little over $4/gallon. I can't tell you the price of 110 fuel or even where to get it here? What's your prices? Also, keep in mind, higher compression ratios will cause more emissions (like we really give a ****?) and it will also increase fuel economy! Great for street cars! Also too, consider this, if you take a roadtrip in your Valiant to a long distance car show and you don't trailer it, would you really want to worry about finding race grade fuel the whole way there and back?

With the water methanol kits, you have the freedom to fill up with 93 octane fuel (it's everywhere) and go to AutoZoo/ O'reallys?/ and Retard Auto and pick up some windshield wiper fluid to dump in you water meth resevoir and there you go! You're on your way.

I apologize if in the previous thread, I might not have had the nicest tone and I was surprised you asked for my input because of that. I was having a very irritable day.
 
kittypancake said:
I do not know, but please keep asking your questions. I am not knowledgeable enough to even ask these questions, but I'm learning a lot reading the responses.
Click to expand...
Shoot, I'm learning things too! I didn't know you could have the crown of the piston come out the block!
 
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