V1 LNF Forged Rods

[Desert Sasqwatch]

Everything I read states the LNF came with factory forged connecting rods, but I cannot confirm a GM part number for them. In some parts sites I'm finding a PN 12654947 listed, but information is indicating this is a LDK PN, which is a powdered metal rod. I did locate another PN 12589414 for a LNF rod, believe this may be the 'original' PN for the LNF and possibly(?) the forge rod PN? If anyone has this information or knows where/whom to ask, please share. Thanks.

 

[Gtstorey]

Take Out LDK/LNF Piston(s) and Rod(s) – ZZPerformance
"These are LDK rods and pistons. LDK rods are weaker than OEM LNF and LSJ rods and are intended for stock or moderate power rebuilds. If you are looking to make considerably more than stock we recommend our ZZP forged rods. "

 

[Machine1515]

Don't the stock LNF rods have crack caps? That would be indicative of a 'Powder Forged" part, or as you stated powdered metal, and not CNC forged. I was under the impression that they were 12589414 but were replaced with 12654957 as an interchangeable part. LNF Rod . Certainly let me know if I am incorrect on this.

 

[Desert Sasqwatch]

The reason I am asking is the LNF crate engine I ordered I believe is a LDK with LNF externals. The LNF Gen 2 block was a foam cast, my crate engine is a sand cast block which would indicate a Gen 3 block, which would be a LDK engine. If this is the case, then it is highly likely to have the PM rods. Since I plan to add a bit more breathing capability to my engine it is imperative to have a forged rod - thus the reason I am looking for the LNF forged rod GM PN.

A set of factory forged rods will be more than adequate up to 300-350HP boost in power. I found a parts supplier with the PN 12589414 rods on sale for $62 each. So a set of forged rods for $250 is much more economical than the premium OTTP is charging (and yes they are more capable rods, but I'm not looking to push 400+HP). Before anyone goes there, the piston discussion to go with better rods is not needed - thanks.

The information @Gtstorey provided is known information and since I most likely have LDK in disguise, getting LDK take out rod/piston set will not help. And all HP connecting rods at ZZP are out of stock. OTTP has Molinar rods, but they are charging about $50 more per set than ZZP price.

 

[Desert Sasqwatch]

Just found another GM PN 12638832 that is claimed to be a forged LNF connecting rod. Looks like it is a replacement for the 12589414 rod too, but zero information on the material of the part.

 

[Desert Sasqwatch]

This is kind of scary - wonder how many of these cheap Chinese connecting rods are being pawned off as true name branded parts?

Tuning Engine Systems Ecotec 2.0 Lnf Forged Rods For Opel Gt Gm Chevy Cobalt Upgrade Turbo - Buy 2.0 Ecotec Rods forged Rods For Opel Gt ecotec 2.0 Lnf Rod Product on Alibaba.com

Tuning Engine Systems Ecotec 2.0 Lnf Forged Rods For Opel Gt Gm Chevy Cobalt Upgrade Turbo - Buy 2.0 Ecotec Rods forged Rods For Opel Gt ecotec 2.0 Lnf Rod Product on Alibaba.com

m.alibaba.com

 

[RCK605]

I wouldn't be too worried about them. Give them a thorough visual examination before installation. These days China's foundry technology is beyond what is currently being used in the US. The OEM blanks probably come from China anyway. The concern would be if the ones sold on alibaba are the OEM QC rejects that GM wouldn't accept.

 

[Desert Sasqwatch]

Would anyone be interested in obtaining a set of forged 4340 connecting rods for their LNF/LDK/LHU? There are choices of H-beam and I-beam rods available from the OEM manufacturers. The H-beam rods are identical to other forged 4340 rods selling for $450+ per set retail. The I-beam rods are beefier than the GM factory forged LNF rods which are no longer available - only the powdered metal weaker LDK/LHU rods at about $300 per set.

These are billet steel, shot-peened, standard size (BE & SE) with bronze SE bearings installed. Per the manufacturer the I-beam rods are rated up to 600+ HP with the correct rod bolts and quality bearings. The H-beam rods are rated 500+ HP with the same bolts and bearings. Both are the LNF length of 145.5 mm center to center (5.704 inch) rods, don't know if they can be used in a LSJ? These are sold 'bare', needing rod bolts (ARP 3/8 inch) to make complete.

I am making queries to the OEM manufacturers, who sell these to HP/racing aftermarket retailers under other company names, to get pricing.

My preference is the I-beam rods (less prone to stress cracking by design), which has a minimum purchase of a lot of 20 rods for an order, so would need 4 other TC builders to participate in this adventure to make an order. The H-beam rods minimum order is 4 rods, but the price may be reduced for orders of 20 or more.

Up front, it looks like approx $175 per set for the H-beam rods and about $200 per set for the I-beam rods, but this is an estimate. The taxes, shipping, and fees to get them shipped to Arizona will add to this cost, which should be included in the query responses.

Send me a DM if you are interested. I will try to pull the details together soon, if I can get timely responses. Maybe this will work out favorably, it never hurts to check into these opportunities that may benefit some of us Goblin family. Thanks.

 

[Tinkles]

I missed this post earlier. My Ecotec literature says the that LNF rods are 1019 steel(same as the L61 and LE5) and LSJ rods are 5115 steel.

 

[mike_sno]

@Desert Sasqwatch did you ended up finding enough participants?

 

[Desert Sasqwatch]

No, I did not. There was no other interest at that time. I have not looked into this again since then, but I now have the finds to start looking again to get the parts I need to upgrade my LNF/LDK. I will look at this again when I get back from vacation. Aloha.

 

[mike_sno]

Great, keep me posted. mālama