Billet vs stock crank
 

Can anyone tell me from experience how it changes the way the engine behaves?

The crank i'm considering is by K1 for a 2.0 CDB.

In behaviour, hardly anything in it that you'd notice from behind the wheel.
The benefits would be reduced windeage and drag, plus greater torsional strength. As it happens we've run stock cranks to 9000 rpm and got away with it!
The windage improvements would result in slightly better breathing. Less drag from the slimmer webs would mean more power at higher rpm's.
The tendency for most billet cranks is also to go for improved oil distribution in the form of cross drilling, an engine saver in certain circumstances!
As far as we're concerned, the jury is out as to the ultimate benefits of a billet crank for most applications unless intended for high rpm use such as circuit racing.
Would I have one of the cost wasn't an issue? sure, why not?

So whats the difference in cost, roughly.

About £500 over the cost of a new nitrided one.;)

They cost allot more than that and Arrow even more so.

you can pick up billet cranks for £900 now, they may not be arrow or k1 but they're still a billet crank doing the same thing.:thumb:

Here ya go, manley are as good a quality as the rest and they're under £900

http://www.ebay.co.uk/itm/2307620619...968%26_rdc%3D1

There are billet cranks like Arrow etc, i would not put Manley cranks in that bracket, the oiling system compared to Arrow leaves a lot to be desired, IMHO.

I would tend to disagree but I don't know enough about the subject to give an educated argument, it'd be good if one of the tuners here did a youtube video comparing WRX>STi>Manley>K1>Arrow weight and design.

I'd say it's one of those areas that is so open to interpretation it leads nowhere.
Some engines when performance tuned have a tendency to fail in specific ways. The Impreza is pretty well served crank wise, and the benefits of moving into billet are only really going to be felt at over 8500 rpm/700 bhp plus or when there is a risk of lubrication breakdown.
I'm inclined to say what looks right could well turn out to be right, which is where Manley as a brand leaves me slightly less enthusiastic. I dare say the products would turn out to be serviceable, but that still doesn't persuade me to supply them.
We've fitted K1 rods for some time, with no reason not to. They even look the part. We've fitted a couple of K1 cranks, which were well finished and more importantly perfectly balanced.
We have had supplied to us a couple of Eagle stroker cranks for Evos that were so badly out of balance they nearly broke our machine! I can't excuse that kind of carelessness on the part of the manufacturers.
The Cosworth billet crank is fabulous, but so expensive hardly any of our customers would go there.
We've seen one Arrow crank, found in a customer's engine. Very nice.
As I don't think I'd be a you tube sensation, I'll pass on that one thanks! :lol1:

What the classic v3 sti cranks like?

When in perfect condition, nothing wrong with it.

What power they good for?

It sounds glib to say "one bhp before it breaks", but that's how it is.
I wouldn't say it's a power issue directly, as you wouldn't use it at a point where it's going to break for that reason. It's more to do with hardness and the lubrication qualities.

While you are here Alan which version of the 2.5 cranks would you say was best to use in a 2.1?

How about an OE EJ257 crank in a 2.35 build? Or should I get e new crank?

We quite got to like the V9 one, it's now been superceded by a different heat treated version.

What are you using it for? fast road, race? BHP? RPM?

How much a built long block 2.1 with my v3 heads and my semi closed deck block ?what power that be good for ?

+1 for the Induction hardened crank :thumb:


Mick

Which version would that be Mick?

With Mahle pistons, K1 rods, ACL Race bearings, new crank, ARP head studs, RCM oil pump, fully overhauled heads, fully balanced assembly, new cam belt, new water pump, finished like this;

Attachment 68714

£4000 inc vat.

500 bhp wouldn't worry it.

Aren't Cosworth cranks made by Arrow?

Dude you don't need a billet crank.

Rumbled :D

Haha