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440Source math problem? #661955 04/05/10 10:31 PM 04/05/10 10:31 PM
Joined: Oct 2005 Posts: 8,860 Ontario, Canada S Stanton OP Don't question me!
Stanton OP Don't question me! S Joined: Oct 2005 Posts: 8,860 Ontario, Canada	Got a 440Source stroker kit for an RB ... 4.375 stroke crank 7.1 rods 1.423 comp. height pistons .009 deck height (down the hole) 10.725 stock 440 deck height so... 4.375/2 = 2.1875 + 7.1 + 1.423 + .009 = 10.7195 ??? What gives ... where's the .0055 gone ??? This is critical stuff !!!

Re: 440Source math problem? [Re: Stanton] #661956 04/05/10 10:38 PM 04/05/10 10:38 PM
Joined: Jan 2003 Posts: 2,734 Charlotte, NC 4 446acuda master
446acuda master 4 Joined: Jan 2003 Posts: 2,734 Charlotte, NC	Any chance that's a typo from 440source on the compression height?

Re: 440Source math problem? [Re: Stanton] #661957 04/05/10 10:49 PM 04/05/10 10:49 PM
Joined: Nov 2004 Posts: 3,544 Syracuse,NY CompWedgeEngines master
CompWedgeEngines master Joined: Nov 2004 Posts: 3,544 Syracuse,NY	Thats very typical. Many combos are figured for 10.720 as to allow for a -.005 clean up cut off the decks to provide a square , clean deck surface as most old blocks need it, and to be honest, most new blocks deck surface finish is pretty poor. If you need to use Cometics or any other MLS gasket, that .005 will give you enough room to correct the RA for proper finish. RIP Monte Smith Your work is a reflection of yourself, autograph it with quality. WD for Diamond Pistons,Sidewinder cylinder heads, Wiseco, K1 rods and cranks,BAM lifters, Morel lifters, Molnar Technologies, Harland Sharp, Pro Gear, Cometic, King Engine Bearings and many others.

Re: 440Source math problem? [Re: Stanton] #661958 04/05/10 10:55 PM 04/05/10 10:55 PM
Joined: Jan 2003 Posts: 4,395 The Pale Blue Dot Skeptic master
Skeptic master Joined: Jan 2003 Posts: 4,395 The Pale Blue Dot	I'd contact Brandon( before yet another inflammatory 440 source post) and let him know....If you really spent money with him and aren't just trolling about a math error on his website. The difference could be taken up with a cleanup deck.... Ma Mopar wasn't that careful with deck heights. Good Luck with that. BTW I checked a few other combos listed on his site, funny thing, that's the only one with a deck height error Last edited by Busfixer; 04/05/10 10:56 PM.

Re: 440Source math problem? [Re: Skeptic] #661959 04/06/10 12:03 AM 04/06/10 12:03 AM
Joined: Oct 2005 Posts: 8,860 Ontario, Canada S Stanton OP Don't question me!
Stanton OP Don't question me! S Joined: Oct 2005 Posts: 8,860 Ontario, Canada	Oh, I spent the money all right !! The block's in being machined and we want to zero-deck it based on the numbers but we need to know if they're correct first. I'll likely make the phone call tomorrow.

Re: 440Source math problem? [Re: Stanton] #661960 04/06/10 12:10 AM 04/06/10 12:10 AM
Joined: Jan 2003 Posts: 5,875 communist bloc of new jersey J jamesc master
jamesc master J Joined: Jan 2003 Posts: 5,875 communist bloc of new jersey	Quote: What gives ... where's the .0055 gone ??? hopefully onto the table of the mill that squaring the block to where it should be. stock deck heights are all over the place. better to have is stack up a little short for clean up room then have it too tall. as mentioned i would consider this common practice not a math error.

Re: 440Source math problem? [Re: 446acuda] #661961 04/06/10 12:38 AM 04/06/10 12:38 AM
Joined: Jan 2004 Posts: 27,347 Today? Who Knows? 1_WILD_RT Management Trainee
1_WILD_RT Management Trainee Joined: Jan 2004 Posts: 27,347 Today? Who Knows?	What it likely is is a typo on the in the hole dimension.. Allot are calculated @.014 in the hole.. This one probably winds up .0145 in the hole.. & I'd be decking the block to 10.710 FWIW I originally decked my current build at 10.720 being conservative & since have shaved another .010 off...

Re: 440Source math problem? [Re: Stanton] #661962 04/06/10 12:50 AM 04/06/10 12:50 AM
Joined: Jan 2003 Posts: 30,994 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 30,994 Oregon	What exactly is the problem? You deck the block to match the rotating assembly. All the piston vendors assume the deck is shorter than blueprint because they are selling parts for 40 year old engines.

Re: 440Source math problem? [Re: AndyF] #661963 04/06/10 02:07 AM 04/06/10 02:07 AM
Joined: Jul 2008 Posts: 607 Boise M Moparteacher mopar
Moparteacher mopar M Joined: Jul 2008 Posts: 607 Boise	I agree. I decked my 383 .050" to get the piston where I wanted it. Now just hope the crank and rods are as advertised.

Re: 440Source math problem? [Re: AndyF] #661964 04/06/10 03:42 AM 04/06/10 03:42 AM
Joined: Feb 2003 Posts: 21,318 Manitoba, Canada DaytonaTurbo Too Many Posts
DaytonaTurbo Too Many Posts Joined: Feb 2003 Posts: 21,318 Manitoba, Canada	Quote: What exactly is the problem? You deck the block to match the rotating assembly. You do a mock up assembely and measure how far each piston is in the hole so you can square it and mill correctly. I would sooner do that than go off of advertised lengths.

Re: 440Source math problem? [Re: DaytonaTurbo] #661965 04/06/10 05:47 AM 04/06/10 05:47 AM
Joined: Dec 2009 Posts: 1,074 detroit, mi POS Dakota super stock
POS Dakota super stock Joined: Dec 2009 Posts: 1,074 detroit, mi	Quote: Quote: What exactly is the problem? You deck the block to match the rotating assembly. You do a mock up assembely and measure how far each piston is in the hole so you can square it and mill correctly. I would sooner do that than go off of advertised lengths. I have friends who think I was crazy to have the bores done first so i could fit the oversized pistons and do a mockup assembly in order to find the true deck height I needed afterwards. IMO taking your time and getting things right is worth the extra trip to the machine shop. Id rather do that, than end up with the compression all wrong, or a problem I can't correct afterwards because i put my head in the sand.

Re: 440Source math problem? [Re: Stanton] #661966 04/06/10 07:07 AM 04/06/10 07:07 AM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	It's only .0055 thou the decks are more often 10.720 than 10.725 and they like to leave a little to square the decks and resurface them. .0055 is not much and would make less than .2 compression difference you would never notice it. My stroker (RIP) needed .015 to square and surface the 40 year old flaws out of the deck. when machinist said they were stock (i did not hear that he wanted .015 to square and resurface) I ordered my custom pistons to be 10.720 0 deck and when we actually started the machining I had to have my pistons cut down .010 or my piston to head clearance would have been .028

Re: 440Source math problem? [Re: Stanton] #661967 04/06/10 08:04 AM 04/06/10 08:04 AM
Joined: Jul 2005 Posts: 428 wappinger falls new york J Jimi_Vignogna mopar
Jimi_Vignogna mopar J Joined: Jul 2005 Posts: 428 wappinger falls new york	Quote: Got a 440Source stroker kit for an RB ... 4.375 stroke crank 7.1 rods 1.423 comp. height pistons .009 deck height (down the hole) 10.725 stock 440 deck height so... 4.375/2 = 2.1875 nominal deck on an rb is 10.720, if it was mine i would make the deck 10.700 and if the pistons are above deeck buy custom cometics in the thickness you need to make the required deck ht. square deck the block first then bore it not vice versa!!!! + 7.1 + 1.423 + .009 = 10.7195 ??? What gives ... where's the .0055 gone ??? This is critical stuff !!! https://www.facebook.com/VignognaRacingEngines

Re: 440Source math problem? [Re: Stanton] #661968 04/06/10 09:50 AM 04/06/10 09:50 AM
Joined: Oct 2004 Posts: 8,165 Left Coast B BobR master
BobR master B Joined: Oct 2004 Posts: 8,165 Left Coast	Quote: Got a 440Source stroker kit for an RB ... 4.375 stroke crank 7.1 rods 1.423 comp. height pistons .009 deck height (down the hole) 10.725 stock 440 deck height so... 4.375/2 = 2.1875 + 7.1 + 1.423 + .009 = 10.7195 ??? What gives ... where's the .0055 gone ??? This is critical stuff !!! IMO. Not that critical.

Re: 440Source math problem? [Re: BobR] #661969 04/06/10 10:25 AM 04/06/10 10:25 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	If you want the real(correct) math,you should install the crank,rods and pistons at all 4 corners,then make your measurments and do the machine work if necessary base on the actual numbers or if you have an accurate way of measuring the block at crank center. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: 440Source math problem? [Re: Stanton] #661970 04/06/10 11:19 AM 04/06/10 11:19 AM
Joined: Feb 2007 Posts: 5,080 organ M maximum entropy master
maximum entropy master M Joined: Feb 2007 Posts: 5,080 organ	Quote: Got a 440Source stroker kit for an RB ... 4.375 stroke crank 7.1 rods 1.423 comp. height pistons .009 deck height (down the hole) 10.725 stock 440 deck height so... 4.375/2 = 2.1875 + 7.1 + 1.423 + .009 = 10.7195 ??? What gives ... where's the .0055 gone ??? This is critical stuff !!! easy there, chief! take a deep breath- there. that's better. is this your first engine? suppliers NEVER sell combos that are zero deck in an unmachined "nominal deck height" block. AND, as an added bonus, they'll give you compression ratios and deck heights based on a number they've pulled out of a hat! some will give you deck height based on -.010 deck ht, some -.015, and so on. ALWAYS mock up and measure YOUR deck height before machining, to avoid "nasty surprises". ALWAYS. if it's off, it's your fault. sorry. for what is the good life if not doing things thoughtfully?

Re: 440Source math problem? [Re: B G Racing] #661971 04/07/10 12:27 AM 04/07/10 12:27 AM
Joined: Aug 2003 Posts: 43,115 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,115 Bend,OR USA	Quote: If you want the real(correct) math,you should install the crank,rods and pistons at all 4 corners,then make your measurments and do the machine work if necessary base on the actual numbers or if you have an accurate way of measuring the block at crank center. I use one piston(no rings on it) and rod on all four corners, mark all the measurments down. Don't be suprised on a stock OEM motor to have taper front to back(or visea -versa) as well as a different deck hieght on one side versus the other side. OEM machine work was not even close to blueprint specs on al the Mopar motors I have blueprinted Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 440Source math problem? [Re: Stanton] #661972 04/07/10 12:36 AM 04/07/10 12:36 AM
Joined: Feb 2003 Posts: 10,200 Someplace you aren't S SomeCarGuy I Live Here
SomeCarGuy I Live Here S Joined: Feb 2003 Posts: 10,200 Someplace you aren't	Get the deck height correct, then order parts to fit that spec. Or cut it down to what a shelf kit needs. Sounds like you are in the latter. I want my fair share

Re: 440Source math problem? [Re: SomeCarGuy] #661973 04/07/10 07:03 AM 04/07/10 07:03 AM
Joined: May 2007 Posts: 430 New Hampshire n_bogie1984 mopar
n_bogie1984 mopar Joined: May 2007 Posts: 430 New Hampshire	ya same way i did mine had it ruff bored, fitted pistons in every cyl to check deck height and rod clearance, then sent it back for final decking and hone. ive learned the hard way to do it right the first time

Re: 440Source math problem? [Re: Cab_Burge] #661974 04/07/10 07:51 AM 04/07/10 07:51 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	Quote: Quote: If you want the real(correct) math,you should install the crank,rods and pistons at all 4 corners,then make your measurments and do the machine work if necessary base on the actual numbers or if you have an accurate way of measuring the block at crank center. I use one piston(no rings on it) and rod on all four corners, mark all the measurments down. Don't be suprised on a stock OEM motor to have taper front to back(or visea -versa) as well as a different deck hieght on one side versus the other side. OEM machine work was not even close to blueprint specs on al the Mopar motors I have blueprinted We usually install the oil ring to make sure the piston is centered in the bore and not cocked,if not it can be off the amount of the wall clearence usually .005 [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

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