My short block is pretty much assembled and balanced. The pistons are pressed fit and they have already been pressed off once as it is.

My question is, can I get the new rods balanced to my rotating assembly? When I got all the components back they said "600 grams" on them. Could I get the new rods matched to those parts already balanced?

And also, will the pistons handle another press-off? They are forged units.
I have asked this question before and a member on this board mentioned that a Mopar piston pin could be used if the piston bores get distorted and need to be honed slightly over-size in order to correct the distortion. The Mopar pin was also said to be lighter, and that's a plus.

I really want to push this engine hard, so I want to feel confident that all the components are up to the task.

This is how far I've got so far with the build.
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You're kidding right? What answer do you want to hear?

You don't balance the rods to the crank. You balance the crank to the rods, pistons, rings and bearings.

 

No, I'm not kidding. I want to know if it's do-able or not. That's the only answer that I'm looking for.

 

Then here's the correct answer.

You have to disassemble the whole short block. Remove the rods from the pistons. Yes the pistons may be effected when redoing any press fit. But if they are you can use the Mopar pin.(.984)
However the new rods are floaters, meaning you won't be pressing the pistons back on. You will be using clips to retain the pins in the rods and pistons. The new rods will also be lighter than the old rods. Therefore the bobweight will change and the crank will need to be respun and rebalanced to the new bobweight.

I thought I covered this before in another post but apparently not.

Good luck.

P.S. How much power are you looking for? If that's an Icon IC887 then that piston will only give you about 9.0:1 with iron heads.

 

Okay I see the problem. I was thinking that maybe the Eagle rods are heavier which may possibly allow the them to be matched to the old rods which I thought may be lighter than the Eagles. Thus being able to match the presumably heavier Eagle rods to the existing weight of the presumably lighter existing rods, and therefore make removing the crank unnecessary since the Eagle rod could be match exactly to the old ones which have already been balanced to the rest of the rotating assembly, including the crank.

Does that sound so unreasonable?

But since the Eagle rod is lighter than the existing rod, the bob weight on the crank would need to be matched to the lighter weight, and possibly even the weight of the lighter piston pin in case of piston bore distortion. Unfortunate.

No I don't think that I have asked this specific question before.

In regards to your question about how much power I want make, well, I really don't have a clear-cut answer but if I had to pick a numbers I would say 450hp and 500ft/lbs tq would be nice. I do plan to get this engine dyno tested since I do in fact desire to know exactly how much power it will make.

And I am not running cast iron heads. I'm going to be ordering Pro Comps, and may even be ordering them this week. I understand that the iron heads have around 80cc chambers while the Pro Comps have around 77cc chambers. I have punched some numbers and have found that I may be able to get around 9.5-to just under 10:1 compression with Pro Comp heads. No, I do not know how far in-the-hole the pistons sit at TDC yet, but I plan to take that measurement soon.

What I am really worried about in regards to connecting rod strengh is RPM. I obviously don't want to see these rods fold in half or break in any kind of way, possibly destroying my engine in the event that I get carried away with RPM. I am the kind of guy that does get carried away, I know that much about myslf, so I feel that I need the stongest engine compenents to survive under what ever I throw at it.

This engine build was supposed to be "low budget" with stock heads and stock rods, and even stock pistons if I could have got away with it, but I have learnd that I do not like the low budget approach. I think that pretty much everything that can be bought aftermarket is money well spent compared to putting money in to old cast iron parts. In the future, almost any old cast iron besides the block is considered JUNK in my book, at least for any performance build.

HOLY CRAP THAT CAME OUT LONG. SORRY IF I'M RAMBLING

 

I wouldn't waste the $$ on eagle rods for that kind of build for that HP output

I have been running my combo for 10 yrs with stock rods and TRW heavy pistons - thousands of street miles as well as hundreds of 1/4 passes and
have never had an issue with the bottom end. Running C heads with stock
steel shim head gaskets netted me right at 10:1 .

car weighs 3950# with me in it - 60' times in mid 1.5's and runs mid 11's in 1/4 mile . Keep shifts under 6000 rpm and you'll be just fine as long as
bottom end correctly balanced. - I do have the bridge straps on my main
caps with studs - but that is all I have done to try to strengthen the bottom end a little over stock .

 

If you get carried away with over revving a 455, and heavy components, it WILL die with stock clearances.
I agree that the aftermarket heads save a step in the build, but
You could make well over 400 hp with mildly ported iron heads and stock rods if you use a good cam/compression/gear combo.

 

You'll need to weigh out the pros and cons of doing this for yourself.

 

Nice 1/4 mile times. Thnx for the info and real world experience. Appreciate it.
10 years ago there was not as much after market stuff for the 455, at least available at the prices they are now, right?
Will heed the warning. I actually thought about running my iron heads but a couple of the valve guides were trashed and they would need a valve job etc.
I went with the Icon 887 because I want to run 91 octane gas without detonation.
What kind of compression and power do you thing that I could get out of this engine given what I have now? I was planning to order a cam and lifter set from you btw.

 

You'll need something in the mid 230@.050 range with lifts in the upper .500's to reach your goals and best use of the heads. You'll probably end up needing to cut the heads in order to get 9.5:1 or better.
The theoretical Hp/tq is based on the use of a Performer intake, 800ish carb and headers.

Thanks

 

Cool man, right on. I'll let you know when I get start working over the heads. Sorry if you thought that I was joking

 

Find out where the piston sit in the block, and deck the block to get the piston close to a zero deck height.

I'm not familiar with that piston so my suggestions are general, but I would think with a minimum deck clearance, thin head gaskets and a mild mill on the heads a 9.5 or better compression ratio would be easy to reach.

My 455 has been together for about 9 years with no major problems. Power Tour, hundreds of dragstrip "miles" and thousands of street miles, still going strong. I really think if you keep the engine revs under 6000 and run the bearing clearance loose then that helps keep the bottom end together.