I have to admit that Im getting myself a little confused at the moment over connecting rods and money. For those the dont know, Im assembling a 400 V12 with the stock 78mm stroke and a 86.5mm bore making 5.5 liter. Most project drift a bit and mine more than most so the engine that started off to be 550hp at 7500 rpm is heading toward 650hp at 8500 rpm .or maybe a little more So, although the original plan called for stock connecting rod with better rod bolts Im now questioning the decision. I can still kind of talk myself into the stock rods since its not a race or track car and will never be a race or track car so it will honestly see redline pretty rarely and for pretty short durations. I know the best thing to do is drop $5-6k on new Ti rods but that is a LOT of money in my world. I could buy the raw Ti and make the rods, I guess that would cut the price about in ½ but would be a ton of work. The next best think would be new good quality steel rods but I honestly dont know how much better they would be than the stock steel rods which are good quality. I know I did run an engine with a longer stroke (82.5mm) in roadraces for 2 seasons at 9000 rpm with no issues. If that wasnt bad enough the rods had a billet small end welded on to the forging to get the length I wanted (the custom carrilo showed up too late to make it into the engine and are still on my shelf brand new over 10 years later ). So after the long lead in, what are others doing? Whos tried what in which engine?
Carrillo is considered the "best". But you will pay for it too. Crower will do custom sizing in both steel and titanium. http://www.crower.com/pdf/157-172.pdf
mark, what the dims of the rods you'll need. I can search thru the wsm's and see if any stock ferrari ones will work.
I'll measure them up tonight. The stock 400 rods will work no problem, but I'm concerned about whether they are strong enough to live to 8500 rpm??? I talked to the shop guys and they're game for making a set of Ti rods for me if I decide to try that. They could be wire edm'd out of plate Ti with very little scrap so I sent out a couple RFQs checking on material.
We've run the stock rods to 9k on boost with no issues - road not track. They are strong rods but heavy, I don't recall ever seeing one fail that was not caused by a different problem. Carrillo and Crower both make good rods but in the past they have always been very slow on delivery for custom bits for us. We have had good luck with Pauter rods and RoDy cranks for quality, price, and delivery time. The steel Pauter rods weigh in the low 400 gram range for a TR length rod if I remember right. The Crowder Ti rods we have run weigh in the low 300's as I recall.
Thanks! I was thinking the rods SHOULD work....but hearing that they DID work puts my mind a little more at easy.
Anybody know how the ferrari Ti rods (355/360) hold up? Are they bullet proof or do the racers still change them out and if so what do they replace them with?
Does anybody know about the life expectancy for Ti rods? Do the threads hold up to re-torquing multiple times? Any corrosion concerns, Ive heard the main bearing journals can suffer galvanic corrosion from the bearings)?
