Inexpensive 5140 Conn. Rods. Yes Or No ?

Posted By: JohnRR

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 07:35 PM

Quote:

K1 4340 billet rods with arp 2000 bolts are less than 500.00, best buy on the market right now. Tim

Not anymore

Posted By: meus31

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 09:21 PM

what is the best buy then ?

Posted By: dragram440

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 09:29 PM

I ran a Cat gear drive in my 440 for years on the street and raced it and it worked awsome.

Posted By: JohnRR

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 09:34 PM

Quote:

what is the best buy then ?

define BEST BUY ... K1 used to be a good buy for a chinese based rod , not so much anymore since it was sold , still a chinese sourced rod ...

Posted By: jamesc

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 09:42 PM

Quote:

what is the best buy then ?

that's a very subjective question and opinions vary. frankly i personally don't care for any of the imported h beams and unfortunately manley wasn't making enough money of their sprotsmasters so they dropped them.

if i was in the market for rods similar to whats being discussed i would look into these. i know they're a lot more and people have successfully used cheaper rods but personally i won't roll those dice. still chinese but hopefully improved quality control and they should be the correct dimensions as they are (i believe) finished by callies. perhaps someone with experience with them can confirm or refute my thoughts

compstar

Posted By: MR_P_BODY

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 09:52 PM

I was sorta fortunate that when Eagle H-beams first
came out(maybe a year after they came out) I bought
a set and had them checked and was very happy with
them so I bought a second set that layed around for
years... the first set is in my W-9 and the second
set I just put in my W-5.... the W-9 has been in
the 9000+ rpm range but normal is 8200.... now days
I hear the quality of them is ... not very good

Posted By: Moparnut426

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 10:16 PM

Quote:

what is the best buy then ?

Well if you think what is the best rod and figure in replacement cost in the factor, say you have a 5000 dollar engine, is it worth sticking a set of 300 dollar rods in it, NO, I guess My thinking is spend up to 1/4 the cost of the engine on the rods, that would make a 1250.00 dollar set of rods "in the market" so Id buy Olivers, or Some Manley or Crower billet stuff.

I didnt spend that much on my rods, but If i was to replace my rods with a like rod, it would be that much. I bought a set of unused Childs terackmaster rods off a member here, and IIRC those were up a grand when they still made them.

Kasey

Posted By: dogdays

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 11:06 PM

Lucky you.

I have to do more with less money, but my engines will never see 6500 rpm.

So here's what I'm thinking about when I select a connecting rod for a 450 hp 440:
440 stock replacement pistons weigh a ton. The change in direction at the top of the stroke can generate several thousand Gs making that two-pound piston "weigh" 7000 or more pounds.

The compressive force on the rod during the power stroke is way less than the tensile forces at the top of the exhaust stroke.

The most highly stressed part of the connecting rod is the rod bolts. Rod failure usually happens either by the rod bolts stretching enough that the rod bearing spins, or else detonation jams the rod bearing into the crank. Detonation isn't the fault of the rod, but rod bolt size is. Now as long as the rod bolt is in its elastic range, it stretches the same amount per psi no matter what the ultimate strength is. The best and quickest way to get the big end to hold together is to go up a size in rod bolts. That increases the area by something like 30% which makes it a heck of a lot easier for the bolt to hold the rod big end together.

The rod beam has it relatively easy. So the main deal with the rod beam is that it be lightweight. Now as a mechanical engineer I look at an H-beam rod and see that it is heavy for its strength. It has a lot of material pretty close to the neutral axis that isn't working very hard. An I-beam rod is much more economical because most of its material is far from the neutral axis. That means it will be strong and lighter.

So I'm looking for an I-beam rod with larger rod bolts that doesn't weigh a ton. That all comes together in that 440Source Chinese rod, it's an I-beam forging with 7/16 rod bolts for $270. It will get the job done at 6500 rpm with stock weight pistons, although I'd rather take the $2-300 I saved on rods and get lighter better pistons. Then the rod will be bulletproof at 7000 rpm and that should get that 440 well above the power level desired.

Now if you can afford $1400 Olivers, go ahead. I have seen them and they are like jewels. But I'd rather spend the money on something that makes more sense.

R.

Posted By: jamesc

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/12/12 11:36 PM

i don't disagree with your logic at all but those cheapie chinese rods scare me. not saying they will cause any problems they could be fine for many applications. as mentioned those replacement piston/pins are like cinder blocks. get rid of those heavy pistons, and personally you can dump those stupid fat pins as well use the .990". these changes go a long way towards unloading the rod whichever you choose.

Posted By: titan

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 01:08 AM

Can The Stock Size Small End Of The Rod Be Bushed For The .990 Pins?

Posted By: MR_P_BODY

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 01:12 AM

Quote:

Can The Stock Size Small End Of The Rod Be Bushed For The .990 Pins?

The pistons would need to be the same size but its
cheaper to just buy the chevy rods and turn the crank...
if you had the chevy pistons ... but if you need to buy
new pistons and rods and turn the crank then its
different

Posted By: d-150

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 01:18 AM

i bought a set of those rods that were bushed for under 100.00.got checked out at machine shop and checked out good.put a set of hyper kb pistons on them.like said before hang a light piston on them

Posted By: JohnRR

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 04:13 AM

Quote:

Can The Stock Size Small End Of The Rod Be Bushed For The .990 Pins?

Yes it could if there is a bushing out there otherwise you could make or modify some ?

Posted By: Eric

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 04:54 AM

Quote:

Lucky you.

I have to do more with less money, but my engines will never see 6500 rpm.

So here's what I'm thinking about when I select a connecting rod for a 450 hp 440:
440 stock replacement pistons weigh a ton. The change in direction at the top of the stroke can generate several thousand Gs making that two-pound piston "weigh" 7000 or more pounds.

The compressive force on the rod during the power stroke is way less than the tensile forces at the top of the exhaust stroke.

The most highly stressed part of the connecting rod is the rod bolts. Rod failure usually happens either by the rod bolts stretching enough that the rod bearing spins, or else detonation jams the rod bearing into the crank. Detonation isn't the fault of the rod, but rod bolt size is. Now as long as the rod bolt is in its elastic range, it stretches the same amount per psi no matter what the ultimate strength is. The best and quickest way to get the big end to hold together is to go up a size in rod bolts. That increases the area by something like 30% which makes it a heck of a lot easier for the bolt to hold the rod big end together.

The rod beam has it relatively easy. So the main deal with the rod beam is that it be lightweight. Now as a mechanical engineer I look at an H-beam rod and see that it is heavy for its strength. It has a lot of material pretty close to the neutral axis that isn't working very hard. An I-beam rod is much more economical because most of its material is far from the neutral axis. That means it will be strong and lighter.

So I'm looking for an I-beam rod with larger rod bolts that doesn't weigh a ton. That all comes together in that 440Source Chinese rod, it's an I-beam forging with 7/16 rod bolts for $270. It will get the job done at 6500 rpm with stock weight pistons, although I'd rather take the $2-300 I saved on rods and get lighter better pistons. Then the rod will be bulletproof at 7000 rpm and that should get that 440 well above the power level desired.

Now if you can afford $1400 Olivers, go ahead. I have seen them and they are like jewels. But I'd rather spend the money on something that makes more sense.

R.

I don't have the pics on this puter...but a 440source rod put a nice hole in my 512...light car thru the traps at 7000k.....

Posted By: jamesc

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 05:11 AM

Quote:

I don't have the pics on this puter...but a 440source rod put a nice hole in my 512...light car thru the traps at 7000k

for most people building engines these days is a real chore. it's always a struggle between what you can afford and getting quality parts/machining/assembly. not knocking any particular brand they can and have all failed. considering the damage they cause when they do fail i always try to bite the bullet and get the better quality parts which almost always have a better record pertaining to failures. this is true of most engine parts, just about anything failing at 7k has the potential to destroy the engine, your wallet and possibly your car. the sad part is today i don't think you can get a set of american forgings/finished rods for under $1000-1200. like i said i always liked the sportsmasters, not a top shelf rod but a quality american part at a reasonable price.

inexpensive parts can really be false economy

Posted By: polyspheric

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 04:49 PM

True - the bolts are the point of failure.
Only a bad nitrous tune will buckle a rod unless it was a poor choice from square 1, and even then the piston may take all the hit.
In general terms the cross-sectional area of a bolt is proportionate to the square of its root diameter. I don't have the actual data, but it should be close to the pilot drill size:
3/8-24 .332"
7/16-20 .3906"

Based on these dimensions the 7/16" bolt is about 38% stronger (assuming equal execution).

Posted By: Crazy68Dart

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 05:38 PM

Since it is nearly impossible to get an American made rod (period) and at that for under a grand (if you have the money it is well spent, but most don't) should the questions be:

- "Who sells the best Chinese rod?"
- "Is the best Chinese rod better/worse than a reworked stock rod"?

Posted By: cl440

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 05:46 PM

Chances are a new "ready to go" connecting rod will still need to be inspected and resized by a competent machine shop. At 475 hp I would save some dough and send a good set of LY's to the machine shop to be inspected and sized. IMO

Posted By: Moparnut426

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 06:25 PM

Quote:

Chances are a new "ready to go" connecting rod will still need to be inspected and resized by a competent machine shop. At 475 hp I would save some dough and send a good set of LY's to the machine shop to be inspected and sized. IMO

Even thought I posted about the cost margine and rods, I do feel the LY rod is a good quality rod, accually any mopar rod from a 360 up to a 440 is a good rod, its been proven many times. Inspect them, shot peen and polish, can be done by you cheaply, but have them magged, and resize. Just have the machine shop do the work of resizing them, and pressing in the bolts.

I did a set of 340 rods by myself, Replaced and swedged new bushings in them, polished the side beams, and shot peened them, then I put a nice set of wave locks in them and as far as I know they are still in the SMF they went to.

I did them in college, and since you say your an engineer your obviously smart and good with your hands so Im sure you can also do all the work your self,ya just need to find a shop that will let ya use the machine

Posted By: d-150

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 09:17 PM

explained in 440 source a rod is like bending a paperclip it gets weaker more its used.not saying the cat rods are any better, but they are brand new.they are speced out to 500hp

Posted By: Moparnut426

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 09:25 PM

So are these and we all know how they turn out, rated to 500hp

Attached picture 7249030-eagle-sir-connecting-rods-box.jpg

Posted By: Moparnut426

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 09:27 PM

Like this.....

Attached picture 7249032-broken.jpg

Posted By: JohnRR

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 09:33 PM

Quote:

explained in 440 source a rod is like bending a paperclip it gets weaker more its used.not saying the cat rods are any better, but they are brand new.they are speced out to 500hp

I'd run a refurbed LY to 500HP before a 5140 chinese I beam rod

Posted By: Anonymous

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 10:01 PM

I just recieved my first set of the 440 Source I beams for $269--They measured as close as any from anywhere and looked darn good to me and a 7 1/6ths wavelock ARP bolt is not going to fail in a 450 HP street engine --the weight was not too bad on them either--I am putting them in a 400 HP street engine with a hyd cam--Yep KB 237's are stupid heavy and these are a tad on the fat side weight wise but-- A 30-40 year old set of LY's Can't be as strong as these new units and when you figure the price diff it is crazy to me to use a 40 year old rod though I do it all the time when I find a good set, get bolts at the flea for 1/2 price/ machine them myself etc THEN they are a good deal for my application. Its a China world boys--I bet there is not a Mopar on this site that is 100% USA--you just can't build an American Muscle Engine all USA wish we could--points to some of the trouble we are in but.....I decided I am powerless to fix it and just want to keep on making a living so I have changed with the times.

Posted By: dragram440

Re: Inexpensive 5140 Conn. Rods. Yes Or No ? - 06/13/12 10:05 PM

Quote:

Like this.....

your telling me this is 100% rod failure? 500 h.p. or under. No other detonation or any other problems.
I had a LY rod twist like a pretzel in my mild 440 to. Should I blame the rod? I dont think that it was the real problem just the weakest link.

Inexpensive 5140 Conn. Rods. Yes Or No ?