440 compression ratio ? - Moparts Forums

Register Log In Moparts Forums Unlawfl's Race & Engine Tech 440 compression ratio ?

Print Thread

440 compression ratio ? #885985 12/23/10 01:13 AM 12/23/10 01:13 AM
Joined: Jan 2003 Posts: 6,743 central new york pettyblue440 OP master
pettyblue440 OP master Joined: Jan 2003 Posts: 6,743 central new york	I have a 440 with 906 heads that cc @ 72.25 w/ l2266 pistons. What cr do I have? Thanks, Jon

Re: 440 compression ratio ? [Re: pettyblue440] #885986 12/23/10 01:31 AM 12/23/10 01:31 AM
Joined: Aug 2003 Posts: 43,176 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,176 Bend,OR USA	Quote: I have a 440 with 906 heads that cc @ 72.25 w/ l2266 pistons. What cr do I have? Thanks, Jon I don't know what the 72.25W/I12266 pistons means If you have the specs. on the piston deck hieght, piston dome or dish volumes, cylinder head combustion chamber volume, bore and stroke and head gasket thickness and bore size go to KB web site and click on calcultors, go to compression calculator and plug your specs in and see what they say you have Same thing plugged into Wallace Racngs web site will probally get a little different calculation Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 440 compression ratio ? [Re: pettyblue440] #885987 12/23/10 01:35 AM 12/23/10 01:35 AM
Joined: Nov 2003 Posts: 6,293 Rock Springs Bob_Coomer master
Bob_Coomer master Joined: Nov 2003 Posts: 6,293 Rock Springs	Close to 10:1 if the heads really are 72cc, they must be milled to a closed chamber (.100 cut). Those pistons are down about .090 in the hole. stock 88cc heads and the same pistons is like 8.8:1 I used a 4.45 x .020 steel shim gasket volume BTW. If a felpro is used it could be .3+ compression less. [color:"red"]65 Hemi Belvedere coming soon [/color] [color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]

Re: 440 compression ratio ? [Re: pettyblue440] #885988 12/23/10 01:49 AM 12/23/10 01:49 AM
Joined: Feb 2007 Posts: 2,315 MOPAR HEADQUARTERS IN ALDEN NY H hemigod426 top fuel
hemigod426 top fuel H Joined: Feb 2007 Posts: 2,315 MOPAR HEADQUARTERS IN ALDEN NY	Quote: I have a 440 with 906 heads that cc @ 72.25 w/ l2266 pistons. What cr do I have? Thanks, Jon are you sure 72cc ive milled 906 heads .040 and put bigger/flatter valves in them all came out to 76cc-80cc MOPAR OR NO CAR

Re: 440 compression ratio ? [Re: pettyblue440] #885989 12/23/10 09:26 AM 12/23/10 09:26 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Quote: I have a 440 with 906 heads that cc @ 72.25 w/ l2266 pistons. What cr do I have? Thanks, Jon wow how did you get the heads down that far? If they have been cut you will have to cut your intake and be careful with your push rods. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: 440 compression ratio ? [Re: Mr.Yuck] #885990 12/23/10 10:56 AM 12/23/10 10:56 AM
Joined: Aug 2006 Posts: 614 Michigan G Get-X mopar
Get-X mopar G Joined: Aug 2006 Posts: 614 Michigan	Quote: Quote: I have a 440 with 906 heads that cc @ 72.25 w/ l2266 pistons. What cr do I have? Thanks, Jon wow how did you get the heads down that far? If they have been cut you will have to cut your intake and be careful with your push rods. My closed chamber 915's are more than that, so I have a little trouble with yours being 72 cc's. The TRW L-2266F's are .070 in the hole approx. Your 906's are probably more like 80+ cc's so with a .041 gasket you probably are in the 9.5:1 area depending on where the chamber volumes really are at. If your chambers really are that small, then you're at 10.2:1 but I really doubt it '65 Belvedere '68 GTX '57 Dodge pickup

Re: 440 compression ratio ? [Re: Get-X] #885991 12/23/10 11:50 AM 12/23/10 11:50 AM
Joined: Nov 2009 Posts: 2,177 ill D dennismopar73 top fuel
dennismopar73 top fuel D Joined: Nov 2009 Posts: 2,177 ill	well i have ran than same combo nowhere near 72 cc heads best 10, more like 9.5-1 bettin man

Re: 440 compression ratio ? [Re: dennismopar73] #885992 12/23/10 12:39 PM 12/23/10 12:39 PM
Joined: Nov 2003 Posts: 6,293 Rock Springs Bob_Coomer master
Bob_Coomer master Joined: Nov 2003 Posts: 6,293 Rock Springs	I have seen a few sets of 906/452's milled so much they are a closed chamber head. Like I say it takes a .100 cut. I milled a set of 516's one time .080 LOL [color:"red"]65 Hemi Belvedere coming soon [/color] [color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]

Re: 440 compression ratio ? [Re: Get-X] #885993 12/24/10 01:01 AM 12/24/10 01:01 AM
Joined: Jan 2003 Posts: 6,743 central new york pettyblue440 OP master
pettyblue440 OP master Joined: Jan 2003 Posts: 6,743 central new york	They are at 72. I had my machine shop check them and they are what the seller advertised them to me as. So I should expect 10:1 compression with this combo? Thanks again, Jon

Re: 440 compression ratio ? [Re: pettyblue440] #885994 12/24/10 01:12 AM 12/24/10 01:12 AM
Joined: Nov 2009 Posts: 2,177 ill D dennismopar73 top fuel
dennismopar73 top fuel D Joined: Nov 2009 Posts: 2,177 ill	mmm yes 'if ' that what they are 10-1 buy the way DO NOT GET THEM HOT Last edited by dennismopar73; 12/24/10 01:13 AM.

Re: 440 compression ratio ? [Re: dennismopar73] #885995 12/24/10 03:44 AM 12/24/10 03:44 AM
Joined: Jul 2005 Posts: 1,559 Oh H His and Her 69's pro stock
His and Her 69's pro stock H Joined: Jul 2005 Posts: 1,559 Oh	The heads gave me 2 points higher on comp when I ran them. I had 10-1 and went 12-1 after milling them. I did run adjustable rockers and I had the correct length pushrods for the combo. I ran the setup for years with no issues. These heads were BETTER then the Indy SR heads I got to replace them with. I ran 3 to 4 tenths better then out of the box SR's. I had to open the SR's to max wedge port just to run faster then the 906 heads. I Hope You get Good use out of them like I did. David

Re: 440 compression ratio ? [Re: His and Her 69's] #885996 12/24/10 04:20 PM 12/24/10 04:20 PM
Joined: Aug 2003 Posts: 43,176 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,176 Bend,OR USA	Quote: The heads gave me 2 points higher on comp when I ran them. I had 10-1 and went 12-1 after milling them. I did run adjustable rockers and I had the correct length pushrods for the combo. I ran the setup for years with no issues. These heads were BETTER then the Indy SR heads I got to replace them with. I ran 3 to 4 tenths better then out of the box SR's. I had to open the SR's to max wedge port just to run faster then the 906 heads. I Hope You get Good use out of them like I did. David I think that this is a good example of iron versus aluminum heads where the iron head keeps more heat in the combustion chambers and cylinders resulting in more power. The flat side of his heads probally resulted in more quench than your average open chamber Mopar production heads(906,346,452) also making some additional power I switch from a set of ported big valve 84. cc open chamber 906 heads to a set of 84. cc CNC ported closed chambered Eddy RPM heads wuith 30 CFM increase on the Eddys and pick up .2 ET and 4+ MPH Exact same compression ratio and same pump gas Lots of things to learn out there Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Moderated by Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer

Hop To

Powered by UBB.threads™ PHP Forum Software 7.7.1