What connecting rods are you custom motor guys using?
 

I went to the PRI show this weekend in Indy and asked all of the vendors which rod they recommended for a BBC marine application in the 800 to 850 HP range at 6500 RPM max. They all recommended their highest end steel rod which seem to sell in the $1000 to $1500 range. Lunati was the only one to recommend something less than their top of the line billet rod. They said the Pro Mod rod ($750) is what they would recommend and said they have many engine builders using them on up to 1300 HP engines. The problem I have is they are rated in their catalog at 750 HP @ 8500 RPM. Anyway I thought I would get some real world info from some of the OSO guys that have had good, bad or otherwise experiences using Pro Mod or any other rod.
Thanks

Oliver or Carrillo are very high on the list although I cheaped out and went with Eagle.

I decided on two choices when I was building mine. Oliver billet or Lunati billet. Both are made in the USA and I have faith in both.

I went with the Lunati billet simply because of a better price.
In my opinion one is as good as the other.

Just my .02
DAVE

I remember Dean telling me that he thought the Eagle H beams with l19 bolts were good to 1200hp with no issues (their crank too).

I don't think I would put 1200hp thru an Eagle crank...

I did speak to the guys in the Eagle booth and they said they have numerous 4.5" and 4.25" strokers in 1800 HP drag motors and haven't had any trouble with them. They did say they that those motors are using Aluminum rods. I know a few guys in Michigan had some problems with Eagle products. I realize the Pro Billet stuff is the best, but it is also the most expensive. The Lunati Pro Mod rods and H-beam types from Eagle and Manley are quite a bit less and will probably do just fine in HP boat motors. Any other opinions are certainly welcome. Like many other OSO wrench turners, I am looking for the best bang for my buck and I am trying to get some more info before I start spending!!!;) Brad, what crank and rods are you running in your blown 540?

Also keep in mind that the weight of the piston has some influence on the rod too. A big `ol heavy ass TRW can give a rod quite a workout. Of course, a 850hp engine probably has some good chit in it anyway, like JE or ROSS.
I`ve heard that Oliver is one of the better choices......

Agreed DonMan. Rods seem to be rated at a particular HP and RPM. Which is more critical in proper rod selection? Marine engines generally don't see much over 6000 to 6500 RPM max, and most rods are rated at 7500 or 8000 RPM. If lightweight pistons are used in an 850 HP motor that sees 6000 RPM, is it possible that rods rated at 750 HP at 8000 RPM will suffice?

I buy a lot of stuff from a place called Scoggin-Dickey in Lubbock, TX (they are close to me). Just thumbing through their catalog, they list some Childs & Albert "TrackMaster" rods for $90 each ($720 set). These are rated to 850 hp. They also show some Crower "Sportsman" rods for $565 set. These are rated at 850 hp @ 8500 rpm. You might get their opinion on rods for a MARINE application. Their tech line is: 1-806-798-4108
I just noticed this is last years catalog, prices may vary......

FYI:
A buddy runs Manley "Sportsman" rods in his BBC that is in a V-Drive drag boat. He sees lots of RPM but for only a few seconds. His rods are rated for 750 hp. He is putting out 700 hp. He has had good results thus far. Also remember: Absolute, spot-on machine work and assembly are also a big key in making engines live at this horsepower level.

Another thing I noticed about the Lunati Pro Mod rod is the lengths it is available. 6.135" to 6.700", all rated at 750 HP. 6.7" rods are for serious strokers and many of them are making 750 HP with a couple of plug wires not attached!!!:p How much safety factor are they putting into these designs?:confused:

My 540's have SRP JE pistons and the Eagle "H" beam 4340 rods in them. They make about 683hp @5500rpm and 694 foot pounds of torque @4500rpm. I have the Eagle 4340 cranks as well. I had an issue with one of the cranks thus far last year. I have since replaced one of the Eagle cranks with a fully counter weighted 4340 Lunati crank. When I was having it balanced the shop doing the balance work told me that the grade of the steel is much harder in the Lunati's than the Eagle's even though they both have the 4340 Forgings. I would use the Eagle rods again, but I think I will stay clear of their crankshafts. I plan on replacing the Eagle crank with another Lunati in my other engine.

KAAMA, did you go with the Pro or Racer series Lunati crank? I am considering a SRP or JE piston, Lunati crank, and Lunati Pro Mod rod rotating assembly. I will also be looking at the Big M and Merlin 3 blocks. My Eagle crank will remain in my 496 until I pull the motor to sell the boat. Then the 496 will likely get detuned and installed in a Corvette or some other muscle car. I am not sure what I am going to build but I am swaying towards another high compression naturally aspirated motor 540 plus inches. Ideally this motor will go in a small cat hull like a 22 Cougar or a 23 WPM. It will be a few years before that happens, but there is no harm in getting another motor on the stand.:cool:

I have been running Oliver for 7 yrs with 1000 plus hp.
Crower also builds a good rod.

We used Manley's 4340 Pro Series "I" Beam rods.
But if cost is no object, Oliver is the best IMHO.

Oliver. The fellow whose family started the company, Bruce Baldwin is a stand up guy and backs his stuff, no questions asked. I believe they are based out of Grand Rapids, MI. I ran their 6.136 parabollic I beam rods in a 470 inch BBC in a 7 Litre hydro. 738 HP at 7600 RPM. 5 mile heats required WOT for up to 3 minutes.

I learned about Oliver products when Chevrolet sponsored my engine program from 87 to 90. J-146 STEELER. Both Peter Guild at Pro Motor in Mooresville NC and Bill Howell from Chevrolet Engineering Raceshop recommended and used Oliver rods in all of our Hydro engines.

Carillo made some good stuff for us as well but they were pretty arrogant when it came to a problem. They always blamed some other part of the rotating assembly for the failure. Bruce Baldwin on the other hand just asked what did we needed, and delivered.

Sometimes it's risky recommending a product. I don't hesitate a second recommending Oliver.

Steve, there is an "Oliver Products" in Grand Rapids, MI at 445 Sixth St.-----is this the Oliver you're refering too? They're a family owned business and have been in business since something like the late 1800's to early 1900's or something. Anyway, they make several different products there like ovens, special pharmacuitcal packaging materials and papers, machinery, cutting blades and just all kinds of sheet metal stuff. So I'm not sure if it is the Oliver you're speaking of, but if it is I'm sitting in a good spot because my company handles the pest management program within the plant. Just wanted to know if you knew for sure----thanks. :)

Mark/KAAMA

Wette,

I am running the same crap KAAMA originated with...at the suggestion of Dean. When my builder/machinist was looking over the job, he did say they had seen some issues with the crank journals of the eagles lately. Said he would look it over carefully to make sure it was okay. Haven't had any issues, but never spin it over 6000 rpm. Maybe others can referee this, but I think the forces caused by rpm much outweigh combustion pressure forces on the rods past a certain point, and run away quickly at the square of the rpm...Just a question of $$$$$$$$$!

we just finished putting together a bbc w/ manley pro alluminums I think they will work out nicely.

Kaama,

Yessir, that's them. Look up Bruce Baldwin next visit. He'll tell you the story of how he got into High Performance stuff and some of his other inventions. He's just a real down to earth nice guy.

His facility reminded me of the plant in Live Oak Florida that makes BRC pistons. Years ago I had a rush order and they said if I came to their plant they'd hand them to me the same day. Live Oak is in Northern Florida about 50 miles south of Georgia and just between nowhere and somewhere,,,,,,

Well the "plant" was an old barn/shed with no windows, just large barn door openings. They've since moved into nicer digs.
Nonetheless, they had state of the Art machinery, were extremely competent and made an excellent product. Sometimes I think our HP parts are like sausage, the less we know about their origin, the better they are :)

Take care

Steve

YOU CAN REALLY SPEND TO MUCH ON RODS AS MOST MANI. TEND TO OVER SELL!
R.P.M. BREAKS RODS IF YOU MOTOR MAKES POWER IN THE NORMAL RANGE AND YOU STAY IN THE WATER A GOOD SET OF EAGLES OR H BEAMS ARE FINE
CHRANKS ARE DIFFERENT STORY LUNITI PRO ,,,,,,PRO ARE THE BEST FOR THE MONEY
SCAT RODS AND CRANKS ????WHAT A GAMBLE BUT SOMEONE HAS MOST LIKLY USED THEM FOR 10,000 HRS AND NO PROBLEM S,
LUCK ,WHY GAMBLE :D :D :D :D