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Distinguished Member
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Discussion Starter #1
What style/material/brand connecting rod would you use in a 1000 HP, 14.5 CR, N/A (with a small shot of NOS), 4.5" stroke, 7300 peak RPM, drag racing engine. I really appreciate any input.
Thanks
 

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just a ski boat with bark
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What style/material/brand connecting rod would you use in a 1000 HP, 14.5 CR, N/A (with a small shot of NOS), 4.5" stroke, 7300 peak RPM, drag racing engine. I really appreciate any input.
Thanks

Depending how much n2o is "small" I would consider aluminum rods because they will take out some of the shock to the crank. Most blown alcohol engines running much boost run them for that reason. What length are you looking for 6.7" or did you squeeze in 6.8" long rods?
 

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Resident Ford Nut
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If you have the pocket book......CARILLO
If not Crower.

I'm assuming BBC use a 6.7" rod 4340 forged will be fine. The rod's in my 565 are 6.536" Crower's and have been seeing 1,100 plus hp since 1993. I understand both Eagle and Scat make some good stuff now, but if I had the money Crower would be my first choice. Manley was also mentioned and I would use them too.

I understand you can get some long life from some of the better Alumi. rod's. If it's a drag race only deal you might be able to get a few season's out of them.

Sleeper CP :D
 

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B1 Racing
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Steel rods all the way IMO. The aluminum deal is cool from the standpoint of lighter rotating parts, lighter overall engine and its easier on the bearings but the whole deal with having to replace them just sucks big time. I dont think your going into alum rod territory with what you described but that is just my opinion.

The lowest quality rod I would consider would be Scat, they are a good rod, I think they are cast over seas and machined in the US but if it were my engine I would sleep better at night with some Manleys or better yet Carillo's in there. Buy something good and they might be good to you for a very long time. Dont skimp on bolt either, ARP or Carillo bolts for sure.

anyone know what the deal is with Carillo? Did they change something in their manufacturing?
 

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B1 Racing
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I understand you can get some long life from some of the better Alumi. rod's. If it's a drag race only deal you might be able to get a few season's out of them.

Sleeper CP :D
I thought I heard GRP says you can get 200 passes on their alum rods in a 7500 rpm engine, i could be wrong but thats what I recall. $1000 every 200 laps? No thanks!
 

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Resident Ford Nut
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I thought I heard GRP says you can get 200 passes on their alum rods in a 7500 rpm engine, i could be wrong but thats what I recall. $1000 every 200 laps? No thanks!
I think BME claims 400 passes (426 series) out of a Blown Alky engine (2,000 hp) and then check every 75 passes , or something like that. Like I said, my Crower's have been in the boat since 1993.

I do know a guy that built a 750 hp 496" ( 12:1, roller cam, good heads for mid 80's) with Alum rods in a jet river racer. The engine was in the boat for 4-5 yrs and was at the river every month during river season. He had good luck with them, also built a 383 for a Camero street car that was damn fast back then.

Just something for him to think about.

Sleeper CP :D
 

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Lurker
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GRP is what the guy's I know use for the aluminum stuff but as CS mentioned, no real reason to use them for this power level.

For steel, Pankl is the best hands down IMHO. They are some of the nicest machined steel products I've seen. Any time you can put the wrong rod cap on a rod and have the size only change a couple of tenths while still measuring good at the 45's is pretty impressive. Their bolt design is less than optimum according to some engineers, but we have yet to fail one (knock on wood).

We used Carrillo for a long time (industry standard for years) but the quality went way down and the design and manufacturing process fell behind the times. We tried to help them make some changes but they weren't interested so we made the switch.

FYI, Pankl just bought Carrillo.

What ever rod you end up using make sure you get the best bolts you can. It is also a good idea to mark the bolts for position, and pre-torque them a couple of times before final sizing. It is also best to stretch them to the high end of the manufacturers limits (and always measure stretch on anything but a very mild build). A few tenths in stretch (from low limit to high) can have a huge impact on clamp load and that is what is most important in keeping the big end round through high stress situations.
 

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Owner/Crew Chief
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I second Pankl's being the best. Now that Carrillo is in the Pankl 'Family' having gotten itself away from Dover Enterprises (who's business practices caused the degradation after Fred Carrillo sold to them), I would expect that in the not too distant future their rods will be every bit as good (if not the same) as Pankl's since Gerold Pankl, Company Founder insists on the highest quality possible for any of his companies products.
 

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Lurker
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I second Pankl's being the best. Now that Carrillo is in the Pankl 'Family' having gotten itself away from Dover Enterprises (who's business practices caused the degradation after Fred Carrillo sold to them), I would expect that in the not too distant future their rods will be every bit as good (if not the same) as Pankl's since Gerold Pankl, Company Founder insists on the highest quality possible for any of his companies products.
Getting rid of Jack was their first mistake (Dover ent.). :|err

It may have come full circle now!! :D
 

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B1 Racing
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I run those LAE Kryponite billet steel H beams, I believe they are a Pankl rod as well?
 

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Lurker
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I run those LAE Kryponite billet steel H beams, I believe they are a Pankl rod as well?

I think Pankl bought them out not too long ago, and those are their "budget series" line of rods (and I imagine a good choice unless your on an unlimited budget) as their top of the line (Pankl) stuff is around $4000.00+ a set.

Did you get my message yesterday?
 

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steelcomp was here
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Dito on the Pankls's. Crower I beams would be my next choice. These are pricy rods, but basically indestructable. I have alum's in the BBFord...first thing going when I go throuigh the engine. Probably replace with Crowers. Looking at over 1Khp there.
 

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steelcomp was here
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GRP is what the guy's I know use for the aluminum stuff but as CS mentioned, no real reason to use them for this power level.

For steel, Pankl is the best hands down IMHO. They are some of the nicest machined steel products I've seen. Any time you can put the wrong rod cap on a rod and have the size only change a couple of tenths while still measuring good at the 45's is pretty impressive. Their bolt design is less than optimum according to some engineers, but we have yet to fail one (knock on wood).

We used Carrillo for a long time (industry standard for years) but the quality went way down and the design and manufacturing process fell behind the times. We tried to help them make some changes but they weren't interested so we made the switch.

FYI, Pankl just bought Carrillo.

What ever rod you end up using make sure you get the best bolts you can. It is also a good idea to mark the bolts for position, and pre-torque them a couple of times before final sizing. It is also best to stretch them to the high end of the manufacturers limits (and always measure stretch on anything but a very mild build). A few tenths in stretch (from low limit to high) can have a huge impact on clamp load and that is what is most important in keeping the big end round through high stress situations.
If you;re going to stretch the bolt that closely to the tolerance (not necessary IMO) you need to keep a record of before and after installation lengths. If ever there's more than .001" variation, the bolt needs to be replaced. They should be torque cycled a min. of 4, preferable 6 times to get the best mating. Not so critical when stretching, but super critical when torquing. An under torqued bolt, especially a rod bolt, is never good. Under torquing will allow the bolt to continue to stretch some under load and this can lead to failure...just like bending a ooat hanger back and forth 'till it breaks. Stretching/bending the same in this case. I always stretch to 75% of recommended as this is what I was tought was mfgr's target % of yield.
 

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GRP or Manley. Party foul about Manley is they don't make aluminum rods anymore. In both my motors I have the super 70s by manley!! We just bought a set of the GRPs (aluminum) and they are sweet. The way the swirl cut the cap is bi**hen. Can't even see a parting line. Absolutely no slop in the cap!!
 
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