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Buster - Long Rod, Light Pistons, Light Crank Alm. Block SL6
https://slantsix.org/forum/viewtopic.php?t=29183		 Page 2 of 13
Author:  LUCKY13 [ Fri May 30, 2008 12:19 pm ]
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Wow, 550 weight, that would have to be a little weak I would think. The stroker rods for the 440's come in at 780 weight ( which by the way would bolt right in to a cast crank slant) and these are some of the lightest in this size I see around. I would expect at 550 they would have to be thin, but maybe not.

Mopar stroker rod, with chevy sizes but Mopar widths.

7.100 lenth, BE 950, 990 pin, 220 journal size. Turn a slant crank .007 and use a .020 chevy bearing and you got a fit. Chevy bearing are made in all types so thats a win/win.

The cast crank slant is looking better every day.


Jess
Author:  Dart270 [ Fri May 30, 2008 8:09 pm ]
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Yep, the flathead Ford has a very short stroke, right, < 3 in? So, loads are much lower than a 225 or maybe even a 170. Who knows...

I like that Mopar stroker rod. Bet they're cheap (in our books).

Lou
Author:  Dart270 [ Thu Jun 26, 2008 2:33 pm ]
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Hey Jess,

That Mopar/Chev stroker rod looks great for the cast crank buildup I am planning. Would really like to get over 7", and esp over stock 6.7", on the rod length.

Lou
Author:  LUCKY13 [ Thu Jun 26, 2008 4:41 pm ]
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They used to be cheaper (around $350.00 a set), I guess just like everything else the gas is pushing the price up. But with the 190,000 psi bolts the H beam rods are around $440.00 and with the 220,000 psi bolts they are around $499.00 in a H or I beam config.


Jess
Author:  Doctor Dodge [ Thu Jun 26, 2008 9:45 pm ]
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Here is a message carried over from the light weight crank message thread. Trying to keep all the important info in one thread:
------------------
With the engine I am doing, we have already reduced the crank's weight to 56 lbs, it is now in the shop getting rebalanced.

Our attention is now focused on the 198 con rods, we just gave a set of those "long rods" a pretty good "hair cut" and now we are taking a bunch of material off the big end.

It looks like we are well on the way to getting 25 lbs of rotating weight out of this combination. :shock:
DD

Image
Author:  Doctor Dodge [ Thu Jun 26, 2008 9:55 pm ]
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Quote:
... So, are you going to narrow the 198 rods, or broaden out the rod journals on your cast crank?
I have been waiting for that question...
We are going to narrow a set of factory 198 rods.
The goal is to get reciprocating weight out of the assembly so milling down the con rods helps remove more weight.
DD

Image
Author:  Dart270 [ Fri Jun 27, 2008 5:32 am ]
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Looks like a great plan.

I am considering best options here for a motor (iron block first) that will stand at least 6000 RPM around a road course and at least 280 HP. May go with a set of Mopar BB stroker rods, or mill some 198s, or...

If your cast crank in Al block works out, that may be the way I go when I build an alum engine.

Thanks, Doug!

Lou
Author:  Dart270 [ Mon Aug 04, 2008 1:42 pm ]
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Hi Doug,

I have an Al block and cast crank layed out next to each other. Looks like a snap to get the crank in there, actually. Hope the Buster build is going well

Two questions:

1) Why not just cut the #3 crank journal wider to fit the forged crank bearing? Looks like you need about 0.080" more width. Are you concerned about meat in the crank?

2) Can you tell me more about that fixture to hold the 198 rods for milling? I have access to a Bridgeport and a set of 198 rods.

Thanks,

Lou
Author:  Doc [ Mon Aug 04, 2008 2:58 pm ]
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Quote:
1) Why not just cut the #3 crank journal wider to fit the forged crank bearing? Looks like you need about 0.080" more width. Are you concerned about meat in the crank?
Yes, I was worried about breaking the crank seeing that Mopar engineering narrowed the bearing in order to increase crankshaft cross-section between the journals. The other thought was keeping the crank 'factory' so replacements could be installed into the block with-out special work.
Quote:
2) Can you tell me more about that fixture to hold the 198 rods for milling? I have access to a Bridgeport and a set of 198 rods.
That is a custom made con rod holding fixture... it works great.
Shoot me a PM if you need to borrow it.
DD
Author:  Dart270 [ Mon Aug 04, 2008 7:42 pm ]
Post subject: 
Good thoughts on the crank. I will likely duplicate if I can find someone game for the main cap/saddle work.

I may take you up on the loaner fixture - thanks!

Lou
Author:  Doc [ Wed Oct 01, 2008 10:14 am ]
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The Buster engine is progressing and things are starting to "come together".

As with all projects, seems to take way longer then it should... one of my machine shops has had the con rods for 4 weeks now. :roll: :(
No matter seeing that the block repair is taking lot's of time.
I have all the repair parts machined and ready to be installed, I will most likely do the install (epoxy work) tonight.

As part of the block's "prep work", we poured some filler into the bottom of the block last night. All the main studs and caps were installed and torqued before adding the 1 inch layer of "bottom fill".

Image

We were careful to pour the filler in slow and introduce it down low, in order to keep it from getting on / up the walls of the water jackets. This worked out pretty good but even with all the care, there is some filler "skin" on the jacket walls, right around the entry point.

I never thought that using block filler would come down to how "cleanly" you can get it installed but that's the trick. Getting the block clean / prepped and the correct material mix is a snap in comparison.
DD
Author:  Dart270 [ Wed Oct 01, 2008 1:50 pm ]
Post subject: 
Doug,

I'm droolin'.

Is that epoxy filler special for aluminum blocks, or just general. Thermal expansion is quite a bit higher for Al vs. Fe, so that should be consideration. Of course, the liners are iron...

Lou
Author:  mopardemon71 [ Wed Oct 01, 2008 9:05 pm ]
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Doc the k1 rods are 100 grams lighter than oem 225 rod's and 198 length. You probably have a surplus of cool parts so just an idea.
Author:  Doc [ Fri Oct 03, 2008 4:29 pm ]
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I am saving my $$ for a set of K1 rods for an all-out race engine but for Buster, some reworked 198 rods will have to do.

Made more progress with the block.
We machined away all the corrosion around the tops of the cylinders.

Image

That left clean iron liner metal and a nice shoulder of outer aluminum, 1//2 inch down from the top deck. Machined-up some cast iron rings to install onto the shoulder, getting the flats onto the rings, so everything fit together, took some "wittle & fiddle" time. :roll: We left the rings .005 higher then the deck to make sure they bottom-out when installed.

Image

Coated all the surfaces with high temp epoxy and pressed on the rings. Put down a layer of waxed paper, then bolted-down a torque plate to hold the new rings in place... we will pull-off the plate tonight, to see how it all came together... stay tuned.
DD
Author:  SlantSixDan [ Fri Oct 03, 2008 4:33 pm ]
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Wow, what an interesting repair! How'd you machine the cylinder ODs like that...???
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