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I couldn't find an 84mm 4340 WBX crank w. std. main & rod journals that I really liked for my Oxy build, so I decided to make one...

The prototype has already been tested with great success in my NA drag engine, and after some minor design adjustments, the the first batch of production cranks arrived in the shop last spring.

This one slides right into the WBX case without modifications using rods w. 5/16 bolts.

I'm shipping worldwide and the crank currently retails at 590$
Send me a PM for interest.

Looks good!! I’ll PM you thanks

I PM'd you as well.

Very nice, are you planing to do a 86mm chevy journal??

It's absolutely possible.
However, I prefer keeping the VW rod journals and 84mm because of the larger cross-sectional overlap between the mains and rods journal it features compared to the 86mm Chevy alternative. The increased overlap gives a stronger crank more resistant to flex at higher revs.
Besides, the case might need modifications internally if the stroke is increased further, which would overcast one of the intentions for this product; to be a bolt-in solution with the right set of connecting rods.
The 2mm increase in stroke would for any given cylinder bore only yield a marginal increase of 2.3% in total cylinder volume - that's hardly noticeable, and you'd gain more by instead taking the time and setting up your engine spec properly That being said, yes, it's absolutely true that there's no "replacement for displacement", but I'd rather make a small compromise on stroke/journal size and end up with a more robust bottom end suitable for a wider set of applications.

Let me know if you have more questions.

Looks like a type 1 crank with the flywheel end 5 bolt. Probably okay for lower power builds, but I doubt as strong as an OE crank.

Yes, it's based on the regular T1 design. Next revision is planned to have the wider "humps" incorporated, resembling the stock WBX design and adding further stiffness to the crank. I will simultaneously modify the forge tool to make room for T4 mains so that the raw forges can be machined to both stock and T4 spec in order to suit the application and costumer preference. All in good time

On another note though; the forged aftermarket T1 cranks have proven to hold up rather well in high power applications over the years, even though they're often used in less rigid (stock) crank cases. It can also be argued that welding and modifying a stock crank in favor of a fresh piece of 4340 forging, is dubious.
In the end it boils down to the builds purpose itself: Most people are simply interested in upgrading their WBX engines, or build a bullet proof Oxy-boxer in favor of the T1 platform. I'm part of the latter group, and my Oxy is working flawlessly up to 7700 rpm thus far


I find the significant difference in sustain between the stock and 4340 crank rather interesting:

tmbryhn wrote: ↑Thu Jul 02, 2020 10:41 am ...Next revision is planned to have the wider "humps" incorporated, resembling the stock WBX design and adding further stiffness to the crank. I will simultaneously modify the forge tool to make room for T4 mains so that the raw forges can be machined to both stock and T4 spec in order to suit the application and costumer preference...

Awesome! Sounds good and good luck with your venture!

Thanks man

Glad to see you here. I've been following your super trick build project on Facebook.

fly by wire twin throttle bodies? wow!