sprinter

Has anyone seen/heard/touched or smelt a LS7 Ti rod that has failed due to over-stressing? I have heard speculation, but have yet to see any confirmed failures (doesnt help that you cannot search "Ti" as it is only 2 letters).

Closest I found is the below thread. The rod failure mentioned seemed to occur after piston failure so not really applicable...
http://forums.corvetteforum.com/c6-z...y-upgrade.html

If there is a "yes" to the question, what was the HP and the suspected cause?

BgBoost1

Jason at Katech shared this picture with me...but I don't know the application. I had a local engine builder tell me that Titanium does not bend...it will only break. This picture shows that it will bend.

Slow Vette

300 shot of juice??

dfinke23

Jason said they have never had a Ti rod failure that was the root cause.
Bowtiguy runs the Ti rods on his LS7 454 and he makes over 600 WHP (700-750 at the crank).

Frenchican

That would be my guess.

Katech_Zach

Woah, woah woah. Lets be clear. That rod bent because the piston failed. It was not the root cause. We've never failed an LS7 rod (root cause).

Frenchican

Ah man... I was just getting settled in for a good "Ti vs forged steel" rod debate.


Well, at least Jason saved about 5 pages of bandwidth on the forum.

Mjolitor 68

My Ferrari mechanic told me that F wants their Ti rods swapped at 50,000 miles bcus they believe the Ti weakens with heat or use by then

Slow Vette

ok so a new fuel pump, tune, forged pistons, bolt-ons, 300 shot of nitrous and we're golden??

sprinter

That picture is a good recommendation for the Ti rods. I would love to know the upper safe limit for HP.

gonzalezfj

The propensity of Ti to break (rather than bend or elongate) depends on the alloy used. Some of the highest strength Ti alloys are relatively brittle and will snap when subjected to loads beyond their yield point.

As you can see from the photo Jason provided, that's not the case with the LS7 rods.

There are all kinds of uninformed "local engine builders" around. Exactly what are the qualifications required to become an "engine builder" other than enough unsuspecting customers to keep said builder in business?

Frank Gonzalez

Katech_Zach

Let me know how that works out for you.

BADZ

Pistons and rod bolts swapped out and your good!!!!! (stock rods and crank are great pieces). Some charge quite a bit to balance the rotating assembly when using stock rods, stock forge crank and forge aftermarket pistons..

Most will say that the root cause of failure is the stock pistons or rod bolts..

Undy

I think Katech likes the solid silcone bronze wrist pin bushings in the rods too, probably a bit more stable at high loads and less prone to deformation. I believe the factory ones are split bushings.

tjwong

Plus Katech uses upgraded bolts which you can order direct from Jason.

obzidian

I have personally seen and held a set of Ti rods that were ALL bent due to a greedy owner with too much nitrous. The liners were all cracked and the pistons were in a bazillion pieces or two!

So, Piston failure was the cause and the rod just twisted over. Now, what surprised me was just how "well" the Ti Rods took the damage after seeing what the pistons looked like.

Any idea what machine shops are charging to balance a forged piston+stock crank/rods? Norm.?

Katech_Zach

So the Ti rods were not the root cause of failure. The original poster is asking for root cause.

bowtiguy

haven't backed that one up yet on the dyno, but its got to be close with the new heads.... we were only 28hp away with the stock heads. I can tell you one thing, the motor revs like no other with the stock Ti rods, callies magnum crank and Katech pistons.

+1 for rebushed Ti rods holding up just fine.

Painrace

Man, you guys are good. Can you help me figure out what went wrong coming out of turn four at Charlotte Motor Speedway in 1987?



Thanks, in advance, for all your help!

Jim

glass slipper

That was quite a few years ago, but after examining the carnage on your desk, I'd say there was a "loose nut" on the steering wheel.