Building a 440 Quench Engine

[Chatt69chgr]

I have a 440 out of a New Yorker that I am planning on using in my 69 charger.  When the New Yorker was built, gasoline was available with a lot higher octane than we have now.  I seem to recall that 98 octane was pretty common.  Now, of course, 93 octane is the highest commonly avaliable.  My questions revolve around how to best rebuild the engine.  As it came from the factory, it had 906 heads which are the open chambered type.  I think Chrysler went to these to get better emission numbers.  They also lowered the static compression ratio.  I think the stock pistons sit something like 90-120 thousands in the hole.  All in all, not real efficient.  I think the HP version of this motor was rated at 375 hp gross (New Yorker was 350hp).  I had in my mind that if I could improve the combustion efficiency a little, I could maybe bump up the hp by perhaps 10% and still have a very tractable cruiser that didn't experience detonation.  I will be using stock cast HP exhaust manifolds (from Year One) and Edelbrock CH4B Intake and plan on either a Holly or Edelbrock 750cfm carb with 4-speed and 3.55 rear.  I would consult Engle or Comp Cams for best cam choice.  From what I have read, it seems there are two possible ways to go:

1.  Use a conventional open chambered stock head (906 or 452) and use what I think are called pop-up pistons.  I think you mill the tops of the pistons to get the desired static compression ratio.  From what I have read, you want to try to achieve 9.3-9.5:1 with iron heads.  I would probably try to use 452's to get the hardened exhaust valve seats.  This route would probably be the cheapest I think.  Has anyone done this?  If so, does the engine run OK without detonation?  What pistons and cam did you use?  I am not sure this would yield a quench configuration but if it works pretty good it sure would save me a lot of money.  And could I ask a final question?  Were the 452's used on both 400 and 440 engines from 1976-1978?  If so, that would make it a lot easier for me to find a set of those.
   
2.  Use a closed chambered head and build a quench engine.  Choices for head would be either 915 (no idea where to get these since they were 1967 items only) or Edelbrock 84cc Performer RPM heads (either theirs or the ones they make for Mopar Performance with the straight plugs).  In the case of the Edelbrock head one would use flat top pistons and run at zero deck height along with .039 Cometic head gaskets to yield the roughly 40 thousands quench height.  I don't know what static compression ratio this would yield but would suppose the pistons would have to be dished a little if necessary to get the compression ratio down to around 10-10.5:1 (aluminum needing about 1 point higher than iron for same operation).  It would be the same story with the 915's except one would be looking for 9-9.5:1 static compression ratio.  Now, according to Just69's website, he followed the 915 route and used speed pro 2266 pistons along with the ch4b intake manifold and stock hp exhaust manifolds.  I think he used a Holly 750cfm carb.  I have no idea what the static compression ratio was on his setup or if he has achieved, in fact, a quench engine.  But I would like to hear from anyone that has followed this second route using either the iron 915 heads or the Edelbrock heads.  How does the engine run?  Any ping on 93 octane gas.  What cam is being used.  I don't suppose anyone knows of any reproduction 915 style iron head do they.  I saw that Mopar Performance has what I think they call a Stage V iron head but it's just a 906 style with open chamber. 

Any responses will be appreciated.

[Rolling_Thunder]

you can still find 915 heads around - they are getting harder to find however...     I have a set i put on my stroker...   this way i could build my 8.5:1 compression short block so when i add a procharger - i can swap to a set of ported edelbrocks i have on the shelf...    and run some high psi...       

my suggestion would be running more common 906's

someone other than i will give you more details on 0-deck pistons and all that

[mikepmcs]

 

[firefighter3931]

1.  Use a conventional open chambered stock head (906 or 452) and use what I think are called pop-up pistons.  I think you mill the tops of the pistons to get the desired static compression ratio.  From what I have read, you want to try to achieve 9.3-9.5:1 with iron heads.  I would probably try to use 452's to get the hardened exhaust valve seats.  This route would probably be the cheapest I think.  Has anyone done this?  If so, does the engine run OK without detonation?  What pistons and cam did you use?  I am not sure this would yield a quench configuration but if it works pretty good it sure would save me a lot of money.  And could I ask a final question?  Were the 452's used on both 400 and 440 engines from 1976-1978?  If so, that would make it a lot easier for me to find a set of those.
   

Option #1 is your best choice inmo. Build a zero deck shortblock with flat top pistons and use the open chamber heads. It will be pump gas friendly at 9.5:1 compression. Use a set of 452 castings with the 90 cc chambers and hardened seats for unleaded fuel. These are 76-78 400/440 heaqds and are plentiful.

When the time comes for E-heads you'll be all set. I have this same combination built waiting to be dropped in the car when it exits the paintshop. The motor made really descent power on the dyno and runs on 93ul fuel. Compression ratio is 10.5:1 static wih .040 quench.



Ron

[Chatt69chgr]

Thanks Ron.  I really appreciate your response.  I have been reading this site for over a year and have noted that you know what you are talking about---particularly when it comes to engines.  I will follow your advice and pursue option 1 with the 452's and zero deck.  Would the Engle K56 be a good cam choice for this combination?  I seem to recall that cam being mentioned a lot on the site. 

[Purple440]

My 440 is out of a '78 New Yorker so I have the 452 casting.  It's at about 9.8:1 and it's detonating, but probably because it's running lean and I only have access to 92 octane.

The cam is going to be swapped and I'm looking at a dual-pattern design because I have no head porting.  Are you porting?

I'm looking at these two cams:
Mix between the k56 and k58 (more on the exhaust side)
http://www.holley.com/60303.asp

[firefighter3931]

Thanks Ron.  I really appreciate your response.  I have been reading this site for over a year and have noted that you know what you are talking about---particularly when it comes to engines.  I will follow your advice and pursue option 1 with the 452's and zero deck.  Would the Engle K56 be a good cam choice for this combination?  I seem to recall that cam being mentioned a lot on the site. 

Chatt, the K56 is a very good cam but like everything it needs to be matched up with the rest of the combo. With the 4spd and 3.55's it will work fine, but i'd be tempted to go with a K58/K60 custom grind if you plan on a set of E-heads in the future. The aluminum heads move a lot more air, both at peak lift and in the low-mid lift range. You want to take advantage of that flow when you upgrade to a better cylinder head and not leave any power on the table. With the factory manifolds you would have this cam ground on a 112* LSA to reduce overlap and maximize cylinder scavenging. It costs a few extra bucks to order a custom stick, but it's well worth it. 

The Speedpro 2355 6-pack replacement pistons work fine in this type of application and weigh very close to the oem slugs so balancing is easy for the shop....very little work involved. Those 2355's will sit approx .020 below deck so you can have the machinist mock it up and measure the deckheight....then deck & square up the block shooting for zero to -.005 in the hole. The factory rods are also fine as long as you resize them and install upgraded ARP rod bolts. This engine won't rpm much past 6k anyway due to the hydraulic lifters (valve float) so the bottom end is plenty strong.

With a stick, i would consider a rev limiter just in case you miss a shift. 



Ron

[Chryco Psycho]

the alum eddy 84 cc head actually acts like a iron 94 cc hed due to heat loss to the alum so you can safely run approx 10.6:1 with the Eddy head of course the piston wil now hit the valves

[dave571]

   
2.  Use a closed chambered head and build a quench engine.  Choices for head would be either 915 (no idea where to get these since they were 1967 items only) or Edelbrock 84cc Performer RPM heads (either theirs or the ones they make for Mopar Performance with the straight plugs).  In the case of the Edelbrock head one would use flat top pistons and run at zero deck height along with .039 Cometic head gaskets to yield the roughly 40 thousands quench height.  I don't know what static compression ratio this would yield but would suppose the pistons would have to be dished a little if necessary to get the compression ratio down to around 10-10.5:1 (aluminum needing about 1 point higher than iron for same operation).  It would be the same story with the 915's except one would be looking for 9-9.5:1 static compression ratio.  Now, according to Just69's website, he followed the 915 route and used speed pro 2266 pistons along with the ch4b intake manifold and stock hp exhaust manifolds.  I think he used a Holly 750cfm carb.  I have no idea what the static compression ratio was on his setup or if he has achieved, in fact, a quench engine.  But I would like to hear from anyone that has followed this second route using either the iron 915 heads or the Edelbrock heads.  How does the engine run?  Any ping on 93 octane gas.  What cam is being used.  I don't suppose anyone knows of any reproduction 915 style iron head do they.  I saw that Mopar Performance has what I think they call a Stage V iron head but it's just a 906 style with open chamber. 

Any responses will be appreciated.

I'm using option 2
915's on a 67 440.
.030 over
speed pro slugs, .016 below deck
.027 cometic gasket (.043 quench)
eddy rpm intake
750 mighty demon
Racer Brown hyd cam.  242 @ 50 with 545 I and 510 E
the 915's have nail head style manley valves, and cc out at 78.

10.6:1 in a calculator.

I am very happy with the motor, but It will sometimes ping on 91 pump gas.  Not 94, but I'm at 3800 ft of elevation too.  I mix in race gas when I'm at sea level.
It makes good power.  11.7 @ 115 with 3815 pounds 4.10 gears and 3600 stall. 

I'm sure you could make it more pump gas friendly, if you had a cam that bled off a little more. 

The best way would be to do it with a D dish piston.  But with the cost of such a thing, and to find the 915's may be cost prohibitive.   

[mikepmcs]

When you guys say quench, is that the term you use to describe the distance to include below deck numbers and the thickness of the gasket itself.  I know the definition of the word quench and have researched(googled) trying to find out what this means but i can't get the meaning in this instance.

forgive my ignorance and hijack.

v/r
Mike

[Chatt69chgr]

Quench is analagous to hitting a tomato with a sledge hammer.  You get the tomato squished out the side at high velocity.  When the distance from the top of the piston to the top of the cylinder head is between 35 and 55 thousandths, you get the best condition for mixing of the fuel charge.  Apparently, 40 thousandths is the optimum distance.  I think it is best if both surfaces are flat.  The part of the cylinder head opposite the valves is flat in a closed chambered head.  If the distance is greater than about 60 thousandths, you get a shock absorber effect that dimishes the quench effect.  I think quench goes away completely above about 80 thousandths.  You can't realistically run quench distances much less than 40 thousandths because wobbling of the piston in the cylinder will cause the top of the piston to hit the cylinder head.  So you want pretty tight clearances between the piston and the cylinder wall.  Have to follow the piston manufacturers recommendations here.  This is my understanding of this.  I would welcome any and all corrections and amplifications with absolutely no hard feelings.  I am here to learn and share where I can.

Question------can the exhaust valves on a 516 head be increased from the stock 1.60 inch to 1.74 inch as a standard machining procedure?  And are the 516's the same casting as the 915's except for the exhaust valve size?

[Scatpack]

Question------can the exhaust valves on a 516 head be increased from the stock 1.60 inch to 1.74 inch as a standard machining procedure?  And are the 516's the same casting as the 915's except for the exhaust valve size?

Yes,many have done this when you cant find 67 440hp 915's or use the 516's or 66 915's and do the same.I always see people talking about getting heads with factory hardened seats,Which is a moot point,no matter which heads you chose you should ALWAYS have hardened seats installed or replace the factory ones in the rebuild.I just had a set of 67 440hp 915 heads built for the 383 in my 69 super bee.There is always a set on Epay,be prepared to spend around 500 bucks plus rebuild for them.Mine cost 308.00 for a total rebuild minus the new valves i bought.This is with new hardened seats.Its about a 100 dollar bill for the seats

[firefighter3931]

Question------can the exhaust valves on a 516 head be increased from the stock 1.60 inch to 1.74 inch as a standard machining procedure?  And are the 516's the same casting as the 915's except for the exhaust valve size?

The 516 is a different casting than the 915. The later 915 is a much better head than the 516 which is arguably, the worst performance head ever built by chrysler. Even with a big valve upgrade you need to rework the ports (and bowls) extensively to get any kind of descent flow #'s out of them. The easiest heads to rework are the later 452's which respond well to minor bowl work and allready have hardened exhaust seats so as long as you keep the 1.74 ex valve there is no need for inserts. If you're going with a .500 lift cam you don't even need to mess with the short turn....the bowl work will fatten up the flow plenty for that application. 



Ron

[Chatt69chgr]

Ron

Thanks for the response concerning the 516's.  I am still going with the 452's but did wonder about that as someone I know had a set of the 516's.  I do have two more questions:

1.  I would plan on using the valves already in the 452 head if they could be cleaned up and were, in fact, serviceable.  If they are not, would a standard steel replacement valve be OK to use or should one use a stainless steel valve?  What are the normal caveats concerning the valve guides, ie, should the be rebushed with bronze guides? 

2.  I looked up the 2355's and see that they have valve reliefs.  Chryco says that if I changed the heads later to Eddys (84cc) that I would run into valve clearance problems.  I would plan on using std rocker arms.  I didn't look up the K56 (or K58/K60) but does the lift on these preclude use of the Eddy's?  It's probably a moot point as if I get this going acceptably with the 452's, I doubt I will change them (I would like to do another project later----maybe a Duster) so need to intelligently spend my money.  But I just wanted to clarify this issue for my own edification as it were.   

[firefighter3931]

Chatt,

(1) if the valves are unservicable just go to Mancini Racing for some replacements. They carry nice stainless valves at a very good price.

Personally, i prefer a bronze guide but if it's a short term fix you can get by having them knurled.....

http://chucker54.stores.yahoo.net/brbstainstee.html


(2) On the E-head/speedpro 2355 piston combo ; piston to valve clearance will not be an issue with a k56/k58 hydraulic grind.  I'm running a custom Comp cams solid with .580 lift and 30* more duration (than the k58/k60) with resulting .80 intake/.98 exhaust P/V clearance. If they hit..... something is wrong.  That is with a zero deck and .040 head gasket, fwiw.



Ron

[Chryco Psycho]

assuming I got a bad set of Eddy heads so the valve hit at .520 lift
the 516 heads can be opened up to 1.81 exhaust valve with hardened seats installed , the intake port is slightly changed between the 516 & 915 but I ported a set of 516 castings & ran my street duster with full stock interior + roll cage weighing 3440 lbs with me in it to mid 11s so the haeds are not bad   

[Chatt69chgr]

Thanks for the info Ron.  I went to the junkyard today and located a set of 452's.  Will be going over there tomorrow to watch while they pull them and make sure they are careful and rockers are kept oriented properly---and to save all the hardware/bolts/etc.  Hope to get them to lift the car and saw off the exhaust pipes with my battery powered 4-1/2 inch cutoff saw so I can remove the exhause manifolds carefully later.  I also want to thank everyone else that provided answers to my questions.  This thread has really been a lot of help to me.