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Titanium Rods

  • No Way, Tiitanium Rods are a stupid idea

    Votes: 1 8.3%
  • Even though I like the idea, there's no way I can ever afford them

    Votes: 5 41.7%
  • Definitely would if the price drops a bit more

    Votes: 3 25.0%
  • I want them, whatever the price (any price drop is just a bonus)

    Votes: 1 8.3%
  • I already have Titaium rods!

    Votes: 2 16.7%

  • Total voters
    12
  • Poll closed .
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Discussion Starter #1
Hiya guys,

OK, so I've been toying around with this idea of getting Titanium rods for my RB26 for a loong time. I finally picked up the phone and called Crower. I half expected them to say "sorry, for what car??" instead I was told "yeah, no problem - we've done them before".

So is there anyone else here that would be interested in Titanium Rods for their Skyline? Economies of scale apply - the more orders, the cheaper the price. As it stands (prices in US Dollars and GB Pounds):

1 set $2640 ($440 a rod) ~ 1689 GBP

The guy on the phone said that for 2 to 3 sets the price would drop to $2570 ~ 1644 GBP

I have no idea what the price would be if something like 10 sets were ordered! I would like to find out though if there is serious interest.

So... let the comments & opinions roll!
 

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Guy,

Have you tried any UK companies???

Like ARROW

And for pistons have you looked at ACCRALITE

As we make some of the finest engine components and racecars in the UK you might as well take a look at using UK engineered stuff....

Just a thought
 

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Alex

I believe there are also crap UK companies, as in every country (not saying these two are in that category, I've got no experience with them). Buy British sounds like Buy Dutch or Buy American. Or Buy German, Buy Japanese. It doesn't say anything about wether you get what you want. At the end of the day, price/performance and other arguments is what counts I believe.

My two Eurocents worth ;)
 

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Discussion Starter #4 (Edited)
Thanks for the links Alex, some interesting stuff there.

Why did I chose Crower?

Well, I was hoping that people would come up with some possible alternatives too. Crower is just a suggestion,
however:

I have had great experience with them in the past (on my 420A Eclipse). My friends also used their parts with wonderful reports and I even knew one guy that had a titanium set, and he loved it.

Also as far as "performance conn. rods" go, Crower has a pretty bulletproof reputation. Part of their reputation is that they are also known to be expensive....

I mentioned a while back about sharing knowledge, so I will not make my future intentions secret..
I plan on building the "lightest" most easy-revving RB26 possible (within financial reason). From flywheel to pulleys to conn rods etc...

Financial reason in my case being: I would spend a bit more on conn. rods, however I don't think I can justify (let alone afford) a $20,000 (guesstimate) crank... :D

I have heard of rumours that Tomei makes a titanium 2.7L stroker kit...
 

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Ti rods

I debated (with myself, I always end up losing, too...) about answering this email for a while.

What do you want to achieve? As in, why do you think you need Ti conrods? I can tell you that there is only one reason to use them, and that is to reduce the mass of the rotating assemblies in the bottom end.

However, this will cause you no end of grief if your pistons are not lightened as well - infact, as a general rule, if you can't maintain the given reduction ratio (weight loss wise) between the pistons and rods, you will find that you will break the Ti rods far easier than conventional steel ones.

The only reason to use them is if you want to rev the engine very, very hard. There is an old racers saying that might apply here: "RPM = Ruins Peoples Motors". Note that I'm talking about RPM's in excess of some 11,000rpm here, under boost - and also consider that you'd also need to significantly alter your cam profiles and entire valvetrain assemblies to cope.

Basically, if you want to stay cheaper, certain steel rods we've tested are more than good enough to make 1200 BHP - I would recommend that you buy such rods and spend the extra money you've saved on better quality and lighter pistons, as they are at the extreme outer edge of the reciprocating assembly, hence their weight makes the biggest difference.

Also keep in mind that the loads you place on the bearings and crank journals are massive, especially when your making serious boost (hence torque) at those revs - engine wear will be nothing short of massive.

To give you an indication of what I'm talking about: One of the test motors I use for development on GTR-700 was recently stripped down and sent off to get analysed (complete stress analysis, from metalurgy through to ceramics).

They called me up and asked me "What was the run time of this engine?". I told them that, all up, including warm up and down time, we estimated between 10 to 11 minutes. I was told that they thought the engine had done in excess of 100,000 hard Km's... :)

Power costs money - but more importantly, it costs you reliability.

Mario.

[Edit: Spelling.]
 

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If I may Mario, perhaps this little fact will bring home to all here the real forces encountered by these reciprocating parts;

At 1000rpm the piston within the cylinder is travellling at 9mph at its fastest moment, 11000 it is travelling at 99mph this don't sound like much until you realise that at TDC it is not moving at all, yet, halfway thru its stroke it is moving at these speeds it always returns to 'zero mph' (no matter what revs) with each stroke.

So that is 0-100mph (well almost) in 37mm (well almost) in just 0.00136sec, you have six of these 'dumb-bells' doing this.
 

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somberg said:
Alex

I believe there are also crap UK companies, as in every country (not saying these two are in that category, I've got no experience with them). Buy British sounds like Buy Dutch or Buy American. Or Buy German, Buy Japanese. It doesn't say anything about wether you get what you want. At the end of the day, price/performance and other arguments is what counts I believe.

My two Eurocents worth ;)
Somberg,

Without wishing to draw this particular point out too long...I picked these two companies as they do have a VERY good reputation.

Note I didn't pick Cosworth!!! :D But I could have picked Mahle in Germany....


Guy,

Good luck with this monster....producing an engine which revs very high is going to involve mega tight tolerances....hope you can do it!!

Have you thought about the one piece design Arrow have...this alone reduces the weight in the steel units...some custom pistons for them might be worth investigating....
 

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Discussion Starter #8
Re: Ti rods

Thanks for the replies guys (and for not holding back, Mario

MarioGTR said:
I debated (with myself, I always end up losing, too...) about answering this email for a while.

What do you want to achieve?
To be honest with you, I don't want an 11,000+rpm beast. As much as I would love it, I do realize the crazy stress and wear that the engine would be put under.

What I do want, is to have an engine that revs fast, and not necessarily super-high. I need the engine to rev faster, in order to spool the turbo faster - if that makes any sense. So that I can run a larger turbo on the street, and keep the boost reasonable (due to increased air flow of the larger turbo). At drag racing events, the boost will be turned up for a few runs, and then put back down to "normal".

I plan on having the engine rebuilt every 10,000kms (or every year whichever comes first) along with the gearbox (Holinger). Most of those KMs would be mild street driving.
OK, back onto the topic at hand, as far as I understand, using 6AL4V Ti gives a conn. rod that is about 30% lighter that its steel equivalent...

So: I shall find out the stock conn. rods' weight and a stock piston's weight and make sure that the Ti conn. rod and new piston have the same weight ratio? Or, if it's at all possible, go for an even lighter piston, than the one that satisfies the ratio?

This would also bring into the equation, the crank's counterweights, and ultimately the flywheel and clutch assembly...

Corrections and comments please!

Should have taken Mechanical engineering instead of Industrial Engineering... oh well...
 
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