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4.375 in a 400 block #562192 12/25/09 11:51 AM 12/25/09 11:51 AM
Joined: Feb 2004 Posts: 3,441 Mo. S supercomp OP master
supercomp OP master S Joined: Feb 2004 Posts: 3,441 Mo.	In a 400 block what are the chances of having piston to crank issues using a 4.375 K1 crank, 6.660 Compstar rods and Diamond 1.120 CH off the shelf pistons number 52008, and are the pins adequate? Will B1bs heads flowing 355 at .700 support a 526ci? It'll be for our S/G Roadster.

Re: 4.375 in a 400 block [Re: supercomp] #562193 12/25/09 12:25 PM 12/25/09 12:25 PM
Joined: Jan 2003 Posts: 16,928 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,928 NC	Put in your numbers for the parts you are going to use. Quote: As far as counterweights hitting the piston at the bottom of the stroke, the typical problem is the piston pin boss, ie metal below the piston pin. This thickness varies a lot from one piston design to the next. My Ross 99496 pistons have 0.150", Wiseco K296A35 have 0.220", my Venolias have 0.180". Everything must be checked at assembly for clearance, but this is the math: CWmax = Counter Weight max dia Pthick= Piston thickness below the pin Pin = Piston pin dia Rod = Rod Length CWmax = 2(Rod - Stroke/2 - Pin/2 - Pthick - Clearance) For example: CWmax = 2(6.535 - 4.25/2 - 0.990/2 - 0.180 - 0.075) CWmax = 2(6.535 - 2.125 - 0.495 - 0.180 - 0.075 ) CWmax = 7.32" dia That happens to be the dia of the "cam cut" on a Callies 4.25" stroke crank counterweight for a BB Mopar. The rest of the counterweight can be larger since it isn't at BDC. I cut my Callies 4.250" down to 7.14" with a 2185 gram bobweight. Balancing will need to be addressed with those counterweights. The balance shop went between the lathe and the balancer to get this close, don't just use my dia with other cranks and bobweights. 5688987-Ross_99496_dim.jpg (78 downloads)

Re: 4.375 in a 400 block [Re: 440Jim] #562194 12/26/09 12:17 PM 12/26/09 12:17 PM
Joined: Dec 2008 Posts: 1,200 UK 6 602heavy pro stock
602heavy pro stock 6 Joined: Dec 2008 Posts: 1,200 UK	FWIW , we've just freshened a 400"/545"....... 4.5 stroke , 4.437" bore , vanolia pistons , BME rods...............can't wait to see this thing run.

Re: 4.375 in a 400 block [Re: 602heavy] #562195 12/26/09 01:05 PM 12/26/09 01:05 PM
Joined: Feb 2004 Posts: 3,441 Mo. S supercomp OP master
supercomp OP master S Joined: Feb 2004 Posts: 3,441 Mo.	Quote: FWIW , we've just freshened a 400"/545"....... 4.5 stroke , 4.437" bore , vanolia pistons , BME rods...............can't wait to see this thing run. What pin height, rod lenght and did you have any piston to crank issues? The reason I'm asking is I don't have the parts yet and would like to know what to expect before I buy parts I can't use. Thanks

Re: 4.375 in a 400 block [Re: supercomp] #562196 12/26/09 01:44 PM 12/26/09 01:44 PM
Joined: Dec 2008 Posts: 1,200 UK 6 602heavy pro stock
602heavy pro stock 6 Joined: Dec 2008 Posts: 1,200 UK	Quote: Quote: FWIW , we've just freshened a 400"/545"....... 4.5 stroke , 4.437" bore , vanolia pistons , BME rods...............can't wait to see this thing run. What pin height, rod lenght and did you have any piston to crank issues? The reason I'm asking is I don't have the parts yet and would like to know what to expect before I buy parts I can't use. Thanks No problem , might take a few days to get hold of the spec sheets , can't remember off the top of my head.

Re: 4.375 in a 400 block [Re: 602heavy] #562197 12/26/09 01:50 PM 12/26/09 01:50 PM
Joined: Feb 2004 Posts: 3,441 Mo. S supercomp OP master
supercomp OP master S Joined: Feb 2004 Posts: 3,441 Mo.	Quote: Quote: Quote: FWIW , we've just freshened a 400"/545"....... 4.5 stroke , 4.437" bore , vanolia pistons , BME rods...............can't wait to see this thing run. What pin height, rod lenght and did you have any piston to crank issues? The reason I'm asking is I don't have the parts yet and would like to know what to expect before I buy parts I can't use. Thanks No problem , might take a few days to get hold of the spec sheets , can't remember off the top of my head. Thanks

Re: 4.375 in a 400 block [Re: supercomp] #562198 12/26/09 04:06 PM 12/26/09 04:06 PM
Joined: Jan 2003 Posts: 16,928 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,928 NC	Quote: In a 400 block what are the chances of having piston to crank issues using a 4.375 K1 crank, 6.660 Compstar rods and Diamond 1.120 CH off the shelf pistons number 52008, I think you can make it work with that rod length and stroke. If it gets close, you can remove some material from the crank counterweights before balancing. A diameter of 7.48" might be tight, but most low deck strokers can get by with 7.25" dia counterweights and that helps clear the block too. But I don't have any specific knowlage with that parts combination. I think you know these are not buy the parts and throw them together type of things. It will take a mock-up (or 2) to check all sorts of things (rod bolts to cylinder bore bottom comes to mind, as well as the oil pickup boss, etc.)

Re: 4.375 in a 400 block [Re: supercomp] #562199 12/26/09 05:15 PM 12/26/09 05:15 PM
Joined: Sep 2008 Posts: 2,840 Flint, Michigan B1Fish540 master
B1Fish540 master Joined: Sep 2008 Posts: 2,840 Flint, Michigan	Quote: Will B1bs heads flowing 355 at .700 support a 526ci? The best example of one on the board is Tom Sweden's B1bS 540 that dynoed at 800 hp.

Re: 4.375 in a 400 block [Re: B1Fish540] #562200 12/26/09 05:27 PM 12/26/09 05:27 PM
Joined: Dec 2004 Posts: 140 sweden street_dart member
street_dart member Joined: Dec 2004 Posts: 140 sweden	I buy the heads from Tom (RT540).I have them on a 500" low deck now. More comp, better cam(Scott), more spring and lighter rotating = 841Hp@6400Rpm. Dodge Dart-67 Dodge Custom Royal Lancer-55 Dodge Dakota 4.7 -05

Re: 4.375 in a 400 block [Re: 440Jim] #562201 12/26/09 10:30 PM 12/26/09 10:30 PM
Joined: Feb 2004 Posts: 3,441 Mo. S supercomp OP master
supercomp OP master S Joined: Feb 2004 Posts: 3,441 Mo.	I think you know these are not buy the parts and throw them together type of things. It will take a mock-up (or 2) to check all sorts of things (rod bolts to cylinder bore bottom comes to mind, as well as the oil pickup boss, etc.) Thanks for the info. It will be checked throughly before it's assembled. I usually have about 10 passes on one buy time it's bolted together the final time. LOL I had to take .225 off our Callies 4.150 crank to balance it so they wouldn't have to swiss cheese it. My friend didn't charge extra for putting it in the crank machine 3 times because I kind of sneaked up on it. We have our own lathe. Thanks for the help everyone it's much appreciated.

Re: 4.375 in a 400 block [Re: supercomp] #562202 12/27/09 10:17 AM 12/27/09 10:17 AM
Joined: Jan 2003 Posts: 16,928 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,928 NC	Quote: I had to take .225 off our Callies 4.150 crank to balance it so they wouldn't have to swiss cheese it. Similar with my Callies 4.250". Originally it was about 7.50" dia on the counterweights (with the 7.32" cam-cut at BDC). After going between the balancer and the lathe, it ended up at 7.14" dia. with a shallow drill for final balancing.

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