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Ok, I'm going with aftermarket 6.8 rods. Anyone got the info for the stroke of the crank and the bore (30 over?) I'm looking at SRP pistions.


Thanks

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RJP
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198.81.17.56 For a 514?
No score for this post July 29 2001, 11:28 PM

If you are doing a 514 the most common offset ground crank is 4.140" [2.220" BBC journal]

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gregaust
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203.17.162.33 STROKER COMBO'S
No score for this post July 30 2001, 5:24 AM

4.39 BORE X4.15 STROKE = 502
4.39 BORE X 4.3 STROKE = 520
4.36 BORE X 4.3 STROKE = 514
4.44 BORE X 4.15 STROKE =514
From what i've seen to use the 6.8 rod you are limited to the 4.15 stroke. K.B make pistons for this,not sure about supplier you mentioned.

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SG236
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64.89.111.50 Stoker
No score for this post July 30 2001, 8:58 AM

I'm going with the 4.44 Bore and 4.15 Stroke with Eagle 6.8 rods. SRP has a ready made piston for the combo!




Thanks

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harry wright
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210.50.56.37 533 cubes
No score for this post August 1 2001, 5:47 AM

i am useing a 4.3 stroke scat crank,4.44 inch bore,6.7 lunati pro mod rods and custom je pistons,with the 6.8 rod you will need spacers for the oil ring,what is the application of the engine, street,drag race ?

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SG236
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64.89.111.50 Response
No score for this post August 1 2001, 10:21 AM

I am planning on having a 4.44 bore and a 4.14 stroke and used with a BBC 6.8 rod with a .990 pin, with JE flattops, and 2.20 rod journal. What do you mean that I will need a spacer? My understanding this is a standard stroker 512 Ford motor. This engine will be used strictly for braket racing in a 70 tube chassis maverick with glide/1.76, 4500 stall, and a 4.88 gear and weighing in at about 2500 lbs.

Please explain

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GARY
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12.13.226.16 HAVE YOUR CRANK IN HAND!
No score for this post August 1 2001, 10:33 AM

YOU HAVEN'T SAID WHERE YOUR CRANK IS COMING FROM IF YOU ARE HAVING ONE STROKED HAVE THAT DONE FIRST AS SOME CRANK WILL STROKE LONGER THEN OTHERS IF IT COMES UP SHORT YOU WILL NEED TO ORDER PISTONS TO MAKE COMPRESSION COME OUT RIGHT.

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SG236
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64.89.111.50 Crank in Hand
No score for this post August 1 2001, 12:28 PM

The crank I'm using is a 1971 stock 460 crank that will be turned to 4.14.

Hope that is the info you need.


Thanks,

Russ

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RJP
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198.81.17.42 Oil ring support for JE pistons
No score for this post August 1 2001, 12:42 PM

If you use the 6.800" rods with the 4.140" stroke the pin location is in the oil ring, a ring support is required to keep the oil ring from flexing. No big deal, just follow the installation instructions provided by JE. Do make sure the dimple is located in the gap otherwise the ring will bind.

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Gary
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12.13.226.15 CRANK IN HAND
No score for this post August 1 2001, 3:29 PM

Some cranks and yes I've seen several ford cranks that the stroke is short I've never seen one that was long its normally say .002 or .004 so Your not starting with a 3.85 stroke. So if your crank strokes to 4.137 or 4.130 You need to know this be for you order pistons.Most shops do not have the tool to check the stroke of a crank so its no surprise if they look at you funny when you ask them to do it and people who sale cranks know your not going to look one more thing its best to leave the rod bearing as big as you can if Your crank will clean up with a stroke of 4.130 and have bearing of 2.200 instead of say a .010 or .020 under bearing its not all bad that crank will be stronger and have two chances at being repaired good luck!

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Mike R.
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32.97.239.33 Pin height
No score for this post August 1 2001, 5:15 PM

I don't think that should effect his piston purchase. If he goes from a 4.140" stroke to 4.130" it will only lower the piston height .005" at TDC. If he's looking for a very specific deck clearance he will have to have the block decked either way to reach it.

For example if he has a 10.322" 71 block with a 4.140" stroke, a 6.8" rod and a 1.420" pin height then he has a piston to deck clearance of .032". If he has a the deal with a 4.130" stroke it has a piston to deck clearance of .037". These numbers are not counting the gasket thickness. In either situation I would probably be removing some material from the block to get those numbers closer to zero.

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SG236
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12.77.90.116 Pin Height and crank stroke
No score for this post August 1 2001, 10:14 PM

You hit the nail on the head Mike. Thanks for the info everyone!


Russ
SG236

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Anonymous
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12.13.226.13 It's The L ittle Detiles
No score for this post August 2 2001, 8:39 AM

It's the little details that make one guy car always run better then the next one and one guys engine go together ez and one have to do lots of extra machine work!

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sg236
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64.89.111.50 Details
No score for this post August 2 2001, 9:11 AM

That is exactly why I have tried to talk with anyone willing to discuss before I go through the trials and tribulations of this project.



Russ
SG236

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GARY
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12.13.226.18 TRUST?
No score for this post August 2 2001, 10:48 AM

One Thing I Have Had To Learn The Hard Way Is Don't Trust What You Are Told Check Every Detail For Yourself. You Mite Have To Buy A Tool To Do it But You Wont Be At The Track Wandering Way Doesn't She Run The Number.

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sg236
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64.89.111.50 Trust
No score for this post August 2 2001, 12:04 PM

Gary,

You are right. I have tried to take all the info recieved and run it past a few engine builders. Hopefully I will make the right decisions based on info that I have acquired.


Thanks,

Russ
 
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