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Old 05-27-2011, 11:56 AM
62SAVOY 62SAVOY is offline
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Help 440 RB con rods

Hello.

I've just open my 440 (+0.060) supposedly NSS prepared (hum...) and I found out that the piston was at 0.13in from the top with standart rod length (6.76).
I don't know the brand of those pistons, but they are "racey" with a 10cc dome,
and 1/16 ring lands. But anyway, since the rods was genuine stock, I need to
replace them, and naturally, I start to look for rods 6.90in length to get "0" deck. And but custom rods at $1800, apparently, that doesn't exist, and I'm
very surprised. After assess other possibilities regarding rods (I know that I could play with out of center crank and deck block machining, but where I live,
I'd better forget) I thought about modifying the small end on new bushed hemi rods (same big end but 1.031in small end instead of 1.094in for RB).
Somebody already did it???
Thank you very much.
Philippe from France
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Old 05-27-2011, 12:24 PM
DartGT66 DartGT66 is offline
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Is NSS Nostalgia Super Stock? I think that there might be some other surprises too, where sis you get the engine? The easiest and cheapest way would be changing both the pistons and rods to something more common. Which heads you have in there? Is the block a factory one? What kind of use is the car going to, gasoline used? Will milling the block get you where you want?
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Old 05-28-2011, 12:23 PM
62SAVOY 62SAVOY is offline
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Default 440 RB con rods

Hi Dart 66.

In fact, regarding NSS, let's talk about the look, because actually, the engine
was in "mild tune". Quickly: standart block +0.060, 906 heads partially ported by former owner and redone by myself with Mopar templates. Big valves, even 1.88 at the exhaust because the 1.81 valves were ready to go through, 237/241° with 1.5 rockers and .550 lift, headers but 1.75, MSD 6 Ignition, Team-G manifold and 850 CFM Holley carb. As I told you, the pistons are race style, very good condition (I forgot this in the last post), but a way below the deck.
As well, the rods were stock with almost no more clearance at the straight cuts...
Right now, I'd like to rebuild this engine budget minded in bracket mode (around
11 seconds) or Super/Street, but with future development in mind (cross ram manifold ,double carbs, S/S cam and torque converter, bigger exhaust). In fact, the former owner was using the car at only 5500 rpm without race gas, explaining the presence of this piston (calculated CR about 9.5). But for the reasons explained above, I'd like at least 12/12.5 CR immediatly with "ideal" squish knowing that I'll have to use race gas. The car will be "strip" only.
Today, I talk with a friend of a friend, a sharp machinist, and I think that we
are going to try to modify a set of Hemi rods, with enlargement and out of center machining of the small end. I'll keep you informed. Nevertheless, if somebody knows at affordable price, 6.85/6.90 CtC rods with same ends dimensions, I am buyer. I'll buy the hemi rods in one week.
Regards.
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Old 05-28-2011, 01:10 PM
Cudadrag Cudadrag is offline
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I bought 6.756" rods from BME to replace my stock 6.768" stock LY 440 rods in my 451. The rods were $500. Very high end aluminum hemi rod for a blown application. It's a bit of overkill but for the price no comparison to Eagle or any other steel high performance replacement rod. Rod weight nearly 100 grams lighter than the stock LY. (It's a little scary on how tight they fit. But they did fit on stock 3.75" forged 440 crank.) The rods came with full Arp 2000 7/16" bolts thus were a significant upgrade compared to the LYs.

I matched them with a light weight Ross piston (1.3" C.H. 4.375" bore) a little machining was needed to the small end of the rod to get the top of the rod to clear the bottom of the piston. The results were a much stouter and lighter rod piston combo for a total of $1100.

What I still don't understand is even though the new aluminum rod is supposed to be .012" shorter the setup actually got me even closer to 0 deck (about .020" under) about perfect for the fuel and compression I was seeking. 12.7:1 (according to my measurements) for E-85 fuel use.

I guess what I'm saying I got lucky. I would recommend measuring everything yourself and not rely on the manufacturers numbers no matter which direction you go.

What is the C.H. on your race style pistons?
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Old 05-29-2011, 12:26 AM
62SAVOY 62SAVOY is offline
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Hello Cudadrag.

And thank you for your post.
Very interesting indeed. That reminded me suddenly that I went several times
in the past on BME site, to have a look on their overstock sale.
I even asked for a quotation last year without answer. As well GRP rods...
Then, I went back one more time, and actually there are very interesting things, but unfortunately none of my concern. And $500 is only for overstock sale, because the regular prices are out of reach. I could manage to have machining
on small end, but not on big one.
Regards.
Philippe
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Old 05-29-2011, 12:59 AM
62SAVOY 62SAVOY is offline
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Cudadrag.

I forgot. During dismantling, I recorded and took measurments about all et every
dimensions but... the piston C.H. And because the block has been shaved, but I don't
know how much, I can't get it by calculation. And the last but not the least,
I work abroad and I am presently in India for still 3 weeks.
Regards.
Philippe
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Old 05-30-2011, 04:15 AM
Cudadrag Cudadrag is offline
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I understand about being out of position. As far as the over stock you are correct. But I have noticed they do a pretty good job keeping it up to date so I kept checking until my size (Or again, what I thought was my size. I of course installed without measuing and that was where the luck came.) was on the over stock list.
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Old 05-30-2011, 06:38 AM
DartGT66 DartGT66 is offline
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The smallends in the aftermarket rods aren't usually very thick. If I were to use a Hemi rod, I would just enlargen the pin hole for proper clearance, but leave it unbushed to retain more material around the pin.
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Old 05-31-2011, 02:03 AM
Cudadrag Cudadrag is offline
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Quote:
Originally Posted by DartGT66 View Post
The smallends in the aftermarket rods aren't usually very thick. If I were to use a Hemi rod, I would just enlargen the pin hole for proper clearance, but leave it unbushed to retain more material around the pin.
True in the steel rod world. The BME aluminum hemi rod is thick everywhere. Thus the tight fit. They practically rub each other on the crank (about .050" apart) They are designed for very high end applications. Typically in the top alcohol and fuel classes. But do work fine in lower applications. Just an over kill. But at $500 a set when "over stocked" the price then is competitive for lower applications. The top of the rod is about .4" thick from the top of the pin. Thus a shorter C.H. pistons (that are not originally designed for aluminum rods) may have clearence problems. I only needed a radius cut on the top of .075". Leaving plenty of material for the pin. Bill Miller of BME e-mailed me saying a min of .25" inch is required to top of their rod.

I also asked if Clevrite CB-1512v bearing will work? Where he replied "It's the bearing I use in my fuel car. Throw them in!" I think he may be a Mopar guy!

At least that is what I found with the BME hemi rod.
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