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Discussion Starter · #1 ·
I was just browesing crower and pauter and noticed some cool stuff pauter offers billet rods for our application and also will make a billet stroker crank to your specs so if someone was looking to do a custom overbore and stroke they could if they had the money :) also both manufacturers offer Ti rods so I was wondering if anyone had any :) I havnt heared of any sets around made me curious?
 

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Any one have experience with Ti rods at all? How do they hold up? How hard are they to ballance in regards to a rotating assembly???

Are the stroker cranks remanufactured or are they new billets? If they're new, you think they could make a crank out of Ti too? hehehehe Imagin how fast that dam thing would rev. with a CF driveshaft, lightened flywheel, all Ti internals and a lightened crank pulley.... If you didn't have stalling issues I'd be amazed. :D
 

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To quote Crowers website...

"Billet titanium rods run $465.75 per rod. Allow 12 weeks for delivery."

Sweet Jesus!!!

That's 2794.50 for a set of 6..... Those things better give me head while driving for that kind of money!
 

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Dog Is My Co-Pilot
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I think Bill Hubble ("countach") was going to put titanium con rods into his black VR4 on his last rebuild. I don't know whether he went through with it or not.
 

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Discussion Starter · #6 ·
I think Bill Hubble ("countach") was going to put titanium con rods into his black VR4 on his last rebuild. I don't know whether he went through with it or not.
I knew i remembered someone was, his car wasnt at GTPro last time I was there I dont think? What ever happened to him?

The new cranks are cnc machined out of billet I believe
 

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we were actually just yestreday talking with our machine shop about this- Ti rods and crank.

Pistons wouldn't work well with Ti- but why not the rest... we were going to continue talking about it... also if we were gonna make a Ti crank and rods- we'd only do it stroker :)
 

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Badassical Baddage
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Ti pistons wouldn't expand/contract with heat properly to work with the block...
 

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Shadowfax said:
we were actually just yestreday talking with our machine shop about this- Ti rods and crank.

Pistons wouldn't work well with Ti- but why not the rest... we were going to continue talking about it... also if we were gonna make a Ti crank and rods- we'd only do it stroker :)
Please pardon me if this isn't totally clear, I/m pretty buzzed.....
But I thought an inherent design characteristic of a stroked (stock) motor was tht it would not be able to rev as high as the standard stock motor with all the fixxins... This has a lot to do with the length of the rod and the angle it is in relation to the piston... I mean the cranck moves the rod farther so it's at steeper angles so it's harder to change direction as fast.

So lighten the whole thing up... Now you have a higher displacement motor (stroker) that has the capeabillity of reaching the same redline as the stock displacement motor... Why not keep it stock displacement and raise the redline that much more? It's tomAtoes/tomaaaateos if you ask me, as long as the car is tuned for the application the HP potential is verry simmilar. especially considering this woulkd be the first car to do it, so none of the real refinements would come about for another 10-20 3SIers dumped thier hard earned money into it and started realizing the strong points and the pitfalls...

Basically what I'm getting at is, the benefits (in my drunken eyes) seem to weight out about even, So why would you so strongly favor a stroker over a stock setup with mild overbore?
 

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Just a drunken afterthought. but.....
If the only reason we're not trying to run High power montero 3.5 litre motors is because we don't have strong enough rods pistons and crancks, why not just use that with the stock bore and stroke and lowered compression?

All of the benefits of increased displacement and nonw of the drawbacks of a stroker design.

Youd need custom pistons made dfore a stroker jkit anyway, shortened skirts and a relocation of the wrist pin, why not just have it all adapted to the montero block?

Sounds like an AWESOME setup to me...
 

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well the montero block gets its displacement from a longer stroke. I believe you can't really bore it out any more then the 6g72.

I would rather have a larger stroke and still be able to rev to 8000 then to be able to rev at 10-11k because in order to get good hp at that high rpm you would have to have a different cam profile to take advantage of it, and it turn it would idle like shit if at all. but now if you had some kinda MIVEC system with different cams now there some ideas!!! please correct me if I'm wrong
 

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Hobbit's got the call!

We could with our stock sized stuff rev considerably higher than we do- Matt I think has pulled a 9Grand a few times. I know I hit 10,400 minimum twice with no ill effects (2nd gear at 120mph!).

I'd rather have the stroker crank setup, able to rev to ONLY 7500 or 8000 and have the bigger displacement.

We've also looked into 3.5L crank and what rods could deal with it...

But we've not even gotten close to maxing the power outta the stock short block- what are we gonna do with extra cubes??? :D
 

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Shadowfax said:
But we've not even gotten close to maxing the power outta the stock short block- what are we gonna do with extra cubes??? :D
Make the same power without having to Max out the block/cams/etc. :D

It would be much easier, and probably more reliable, to make 500+ crank HP on the 3.5L with Custom rods/crank/pistons than it would to build the stock motor on stock internals.

The reason I say stock internals is beacuse if your going to upgrade the crank/pistons/rods on the original block, it probably wouldn't cost much more to do it stroker style ;)
 

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enough! Hush! :)

Yeah, so we're looking into this. Really I don't know why it hasn't be done earlier- at least using the montero crank, some custom rods and such...

The builder of my engine actually recommends cast cranks if they can take the power- found they are typically lighter :)

I dunno since I never weighed cast vs forged... but Ti would be hella lighter.

Just to do some research then
 

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I read a quote somewhere about connecting rod weights... I doubt it was for our cars but... The forged connecting rod weight was 7xx grams and Ti was 3xx grams so you're looking a LOT lighter...
Now imagine that same scale only the size and weight of the crank... knife edged and bluprinted/ballanced... Ahhhhhhhh. I think I'm gettting turned on.
 

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This is something I have been looking into for a while. Ever since I read about the kit for the Skylines that raises the displacement by like 0.3L. It would seem like a really good mod provided it was done correctly i.e not 383 stroker style.

I think that some of the reason behind the low revving stroker motor has something to do with the extreme rod angles and that if the revs get too high the piston no longer slides but *walks* up the bore of the motor. This is a characteristic of 383 stroker motors. I have actually seen a 383 motor with a walked bore... not pretty. Picture cylinder walls that resemble the inside of a flexible hose. Bubba Sparx ugly...

Also, not positive on this or not, but I remember reading some of QuickassVR4's posts about his 3.5L Montero transplant and him saying that the Montero block is actually wider than the 3S block.

devilmanVISA
 

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Also, not positive on this or not, but I remember reading some of QuickassVR4's posts about his 3.5L Montero transplant and him saying that the Montero block is actually wider than the 3S block.
It's a little taller and wider. This moves the cylinder heads up a bit, and also pushes them farther apart. Now the lower intake won't fit without spacers. The exhaust manifolds and turbos are closer to the radiator and firewall. I think the motor mounts are affected too. The coolant housing doesn't line up either. There's a lot of little things that are affected by that seemingly minor increase in deck height.
 

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About Titanium rods...

Some inherent problems with using Ti rods that I think you guys are overlooking...

Ti likes to gall, meaning it will sort of "exhange metals" with steel when they're rubbing against each other. Material will transfer from one side to another so you have to be carefull with your steel bolts with Ti (by getting coatings or silver platings on them). Also, the Ti rod is going to want to stick to the sides of your rod journal, so the whole Ti rod has to be coated (with something like moly disulfide and titanium nitride, etc).

Ti is also notch sensitive. If it collects stratches on the surface, it will form cracks.

Ti also has half the endurance strenght of 4340 steel. So before going on about how Skylines use titanium rods and whatnot, those engines are built to last for minutes. Those engines have immensely high rev ceilings (11,000rpms+) and they are constantly torn down and have their deformed/broken parts replaced. But thats the price you pay for making that kind of power. Same goes for those 6000-7000hp Top Fuelers Methanol Dragsters... They use aluminum connecting rods which are usually found broken or stretched, as a minimum, after a run.

Your interest should be towards reducing the weight of the piston, not the crankshaft. The piston is at the very end of the rotating assembly, thus having the largest affect on the assembly.
 
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