Re: Obtaining quench in a slant 6?
[Re: slantzilla]
#931528
02/24/11 07:48 AM
02/24/11 07:48 AM
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Joined: Jan 2005
Posts: 4,862 the frozen wastes...
Pale_Roader
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Swears too much
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Posts: 4,862
the frozen wastes...
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Quote:
300 is doable, but I'm not sure I would call it a "budget" build. 300 N/A is also getting right on the ragged edge of a streetable Slant.
More is not always better when porting a Slant head. Be careful when choosing valve sizes too. What makes for great flow on a flow bench does not necessarily work on an engine because of the small bore.
Dig around on www.slantsix.org and you will find an engine build matrix that details many of the motors we have done.
Heh... i probably shouldn't (i'm confused enough about what to do with this car...) but i will. I actually have (or had?) an account there. Made it when i was asking questions for my brothers build.
Thanks. As neat as this car is, and as much as i wanted to buy a 6 car (at the time) because it would be less structurally damaged than a V8 car, i'm now thinking i should have just got a 318 car instead.
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Re: Obtaining quench in a slant 6?
[Re: jbc426]
#931531
02/24/11 07:34 PM
02/24/11 07:34 PM
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Joined: Jan 2003
Posts: 20,201 Park Forest, IL
slantzilla
Too Many Posts
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Too Many Posts
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Posts: 20,201
Park Forest, IL
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When I first put my good motor in my '66 it would get almost 24 mpg with 3.91 gears driving 60-65. I fixed that when I starting adding more camshaft and the lift got over .525". Even at the end it would get 16-17.
"Everybody funny, now you funny too."
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Re: Obtaining quench in a slant 6?
[Re: Pale_Roader]
#931533
02/28/11 06:23 AM
02/28/11 06:23 AM
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Joined: Sep 2005
Posts: 1,202 California
polkat
OP
mopar addict
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OP
mopar addict
Joined: Sep 2005
Posts: 1,202
California
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One of the main advantages of quench is the turbulance it creates in the mixture, effectively forcing it towards the flame front, which also helps cool the chamber. As a result, you can run higher compression that will actually detonate less then a somewhat lower compression engine without quench.
However, quenching a sl6 might indeed create compression too high for present gasses. So, if one could find a piston that has enough compression height (positive deck) to reach up into the (unmilled) head, and has an offset dish of the right size to drop compression enough, I think it would work. But...does anyone make such a piston, or does one exist that could be modified with a dish?
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Re: Obtaining quench in a slant 6?
[Re: polkat]
#931534
02/28/11 08:59 AM
02/28/11 08:59 AM
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Joined: Jan 2005
Posts: 4,862 the frozen wastes...
Pale_Roader
Swears too much
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Swears too much
Joined: Jan 2005
Posts: 4,862
the frozen wastes...
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Quote:
One of the main advantages of quench is the turbulance it creates in the mixture, effectively forcing it towards the flame front, which also helps cool the chamber. As a result, you can run higher compression that will actually detonate less then a somewhat lower compression engine without quench.
However, quenching a sl6 might indeed create compression too high for present gasses. So, if one could find a piston that has enough compression height (positive deck) to reach up into the (unmilled) head, and has an offset dish of the right size to drop compression enough, I think it would work. But...does anyone make such a piston, or does one exist that could be modified with a dish?
Its been a while since i had my hands on a slant 6 head, but i'm picturing a combustion chamber more or less like a 906 BB head. I'm still not a fan ov quench pads for building open-chamber headed quench engines, and would instead try to just mill the 'step' (the flat shallow area the quench pad would fit into) completely down until the deep part ov the chamber was now essentially a closed chamber (heh heh... hope that makes sense). That done, simply get a custom piston with whatever dish you need to make your target CR. Again, i haven't looked at a /6 chamber in a while... so i might be way out there on this... But if it works it would be better than the hokey quench pad idea. Custom pistons are considerably cheaper than they used to be.
The monkeywrench here could be that the 'step' is too deep and would necessitate decking the head far enough that the deck itself would be too thin.
Just thinking out loud here...
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Re: Obtaining quench in a slant 6?
[Re: polkat]
#931537
03/01/11 10:22 AM
03/01/11 10:22 AM
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Joined: Jan 2005
Posts: 4,862 the frozen wastes...
Pale_Roader
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Swears too much
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Quote:
Yea, it would be too deep. The recessed area in the head is nearly .200" at the edges, and taking that much off the head would make the head deck a bit too thin.
I have heard about a piston, the KB268, that might work for this with the 198 rods. Will check it out.
I figured it might be too deep. The big block head looks doable, and some here have done it. But .200" would pooch that head i'm sure, unless the decks are 1/2" thick. Heh heh... its a slant 6, you never know, gotta be SOME good reason why a tiny 6 cyl engine can weigh 475lbs...
And last i checked (3 or more years ago?) there was no non-Mopar head that could be physically bolted onto/mated to a slant six. Apparently the slant guys have tried EVERYTHING... and i do not doubt them. But... it has been at least 3 years... and there have been a few I-6's introduced into the automotive world. If i was a slant six guy, that would be my quest... finding a modern head to bolt onto that block. Beyond the obvious benefits, making quench would be easy. But i suppose we're transcending the original question now...
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Re: Obtaining quench in a slant 6?
[Re: slantzilla]
#931539
03/02/11 10:11 AM
03/02/11 10:11 AM
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Joined: Jan 2006
Posts: 8,162 USA
360view
Moparts resident spammer
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Moparts resident spammer
Joined: Jan 2006
Posts: 8,162
USA
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Does the Australian Hemi 6 engine tell us what Chrysler intended to do to improve combustion in the Slant 6? http://en.wikipedia.org/wiki/Chrysler_Hemi-6_Engineit seems that instead of quench they went more for 'tumble' in the intake tract to increase burn rate through more turbulence at lower rpms
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Re: Obtaining quench in a slant 6?
[Re: 360view]
#931540
03/02/11 07:30 PM
03/02/11 07:30 PM
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Joined: Jan 2003
Posts: 20,201 Park Forest, IL
slantzilla
Too Many Posts
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Too Many Posts
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Park Forest, IL
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The "Hemi" 6 has nothing in common with the Slant. Nothing in common with a Hemi either.
"Everybody funny, now you funny too."
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Re: Obtaining quench in a slant 6?
[Re: slantzilla]
#931541
03/02/11 07:42 PM
03/02/11 07:42 PM
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Joined: Jan 2003
Posts: 104,346 Garden Grove, CA
OzHemi
Penguin-hating Ginger
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Penguin-hating Ginger
Joined: Jan 2003
Posts: 104,346
Garden Grove, CA
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Quote:
The "Hemi" 6 has nothing in common with the Slant. Nothing in common with a Hemi either.
Yep...it's more of a poly/canted valve....Hemi sounded good though and that is what they just went with in Oz.
It's a "foot" longer than a slant too
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Re: Obtaining quench in a slant 6?
[Re: OzHemi]
#931547
03/03/11 05:41 PM
03/03/11 05:41 PM
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Joined: Sep 2005
Posts: 1,202 California
polkat
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mopar addict
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Posts: 1,202
California
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Back to the idea of quench on a slant (my original post). Here's an idea I posted over on the Slant 6 site. Got no responses so I thought I'd post it here.
Based on the factory numbers (and I have not yet specifically measured out this engine), the head chambers are recessed into the head about .200", while the piston usually sits about .140" in the hole. I'll use these numbers just for arguement.
If the 198 rods are used instead of the 225 rods, it will push the stock 225 piston roughly .147" OUT of the hole. This will give a quench (at the closest points between the head and piston) of about .073" with a .020" steel gasket. Mill the head .028" to clean it up and I'll have about .045" quench (considered good quench in most circles). But the compression will be way to high. So if I cut about a 18cc "D" type dish in the stock piston tops, I'll get roughly a 9.5:1 compression, plus have valve clearance. I've seen this done to other types of stock pistons and assume it's possible here. All of this must be measured out on my specific engine (particularly negative piston deck, since as previously mentioned, it varies between engines, as well as the 198 rod to 225 piston skirt clearance).
I suspect this will work if I can dish the pistons. I'd love to find a piston already like this. The KB268 is close, but the CH is too low. I don't mind the idea of the stock 225 piston as I don't plan to rev beyond 5K anyway.
Any opinions on any of this?
Last edited by polkat; 03/03/11 05:45 PM.
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