Forged or billet rods?

Twinturbor

Well-known member
Does anyone have some stock length rods that are forged or billet they dont use anymore? I dont want to wait and have some manufactured
 
Does it matter what the piston pin diameter is?

What happen to the 6.200" LS rods you were looking at using?
 
If someone does an aftermarket rod it generally is 6.8" long to reduce both piston weight and side loading.
To my knowledge FTF is one of the few that has done an aftermarket (Oliver) rod for the 300.

For extreme turbocharging the Compstar CSB6385DS3B4AH with a custom piston is the least expensive combination.
https://www.summitracing.com/parts/cpi-b6385ds3b4ah/

The LS rod is not supposed to have an offset. Some companies sell the the early gen SBC rods as LS rods.
With all the offset SBC rods being used in an LS engine that is not supposed to have an offset I'm not seeing reports of failures due to the mismatch.
I don't see an .030" offset as a big deal.
The rod bearing is the one that transfers the force to the crank so it's side to side position is more important.

Don't forget that with the LS rod you have an extra .050" side clearance at the crank so you can almost center the rod on the piston by using a spacer on the piston pin for piston guided rods rather that crank guided.
 
Also, V8 rods only have a chamfer on one side of the B/E for radius/filet clearance,so you will have to chamfer the other side before using them. If the are offset, you can also just trim the side of the S/E to keep it from rubbing inside the piston pin boss.
 
I ordered my rods yesterday. What material would you reccomend for spacers on the small end to center the rod?
 
It depends on how thin they need to be.
If they are under .100" I would use steel if they are much thicker then use aluminum.
Whatever you use they must fit snug on the piston pin or they will damage the pin.
 
Curious how this turned out for you. The LS " DISCOVERY" by Muller may be the best news we have had in a good long while . when , if I get around to my turbo long block, the LS for a turbo will be my choice.
 
sdiesel":3uv01eak said:
Curious how this turned out for you. The LS " DISCOVERY" by Muller may be the best news we have had in a good long while . when , if I get around to my turbo long block, the LS for a turbo will be my choice.
Do you really want to deal with having to make wrist pin spacers when you could use the small journal BBC rods instead and not have the hassle?

The OP is doing this to make a set of rods fit the pistons he already has.
 
No, I really don't want to do this in either case, I am however curious about his result. Furthermore by the time, if it ever happens I build a turbo long block, I will hope for a perfect resolution to this rod/ piston combo. You have done a lot of work on this and I until recent times, half paid atten as it is not pertinent at the time. None the less it does goad me into asking his result
 
The extra 80-90 grams of the "BB" rod, over the longer "LS" rod, is likely in the big end, if I were to guess. At least that's how my Eagle set was 15-20 years ago. Maybe not a big deal, but a deal. Not sure on the weight/strength math of the .990 pin, either, but a box-skirt piston probably makes that moot, with no unsupported pin.
 
Firepower354":y4qwmez6 said:
The extra 80-90 grams of the "BB" rod, over the longer "LS" rod, is likely in the big end, if I were to guess. At least that's how my Eagle set was 15-20 years ago. Maybe not a big deal, but a deal. Not sure on the weight/strength math of the .990 pin, either, but a box-skirt piston probably makes that moot, with no unsupported pin.
The small journal BBC rod weighs about the same as a 240 six rod (just over 700 grams) with the same big end/small end weight ratio.
The 240 rod has seen use over 7000 rpm in several engines.

A turbocharged engine will not need to rev much over 5500 rpm to make as much power as the block can handle.
 
Settled science then...
I just don't see the harm in exploring other options, LS, 5.4 Mod, etc
Longer, lighter, lighter pin, all seem like things that are good?
There's more than one way to skin a cat. "Oh, reeeeealy?"- ALF

I haven't had a 240 rod to note weight, but it must be a nice piece, compared to the 785g 300 rod (w/bearing)
More like the 710g 292 rod I'mma use, I guess?

[image]https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/119459924_10223380820005566_4520443278234466369_o.jpg?_nc_cat=105&_nc_sid=8bfeb9&_nc_ohc=9GAAz3M65JcAX_nUY-w&_nc_ht=scontent.fdet1-2.fna&oh=efb0a5bd366cb3bd591688aaf64a9775&oe=5F867029[/image]
 
Absolutely. All rod and other component options need to be explored for the Ford six.

Here is what the 240 rod looks like after removing all forging lines, shot peened and resized with ARP bolts.
Big end is 537 grams (without bearings) and the small end is 177 grams for a 714 gram total. Piston and pin weight is 574 grams.
https://www.dropbox.com/s/k9u6bhvzw0p5w ... .jpg?raw=1

For comparison the Molnar BBC small journal rods is 716 grams
 
I'd forgot what a handsome setup that was. Probably less coincidence than design target similarity, my piston/pin/rod combo is 2g heavier. With bearing but not yet ground beam.
 
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