4 counter weight cranckshaft

[Adams]

Hi all,

I was wondering if anyone has some practical info regarding the use of nissan 4CW crankshafts - 12200-2J200 - especially while building an S14a SR20 with a VE head conversion. These cranks are used in a variety of SR20s, in the EU mainly P11s, N15s and such. Some background on the potential applications can be found here: https://shop.zedperformance.co.uk/18...det-crankshaft

Our primary measurements on a used unit seem to confirm that it would fit the S14a SR20 however we are still dubious about building an engine originally aimed at around 650 bhp with scarce hard info.

Does anyone have any intel on how these perform, how they handle power compared to stock units or about longevity issues? Pretty much any info would be appreciated at this point

Rgds!
Adam

[green_rs13]

i was going to buy one as they were pretty cheap a few years back but didn't after some research
think i remember people saying they wasn't as strong and they could bend them or something along those lines which changed my mind on them.

[s14guy]

Well... Im a newbie here but actually I have something to say on this. No offence but I think "few years back" and "people saying", "could bend them or something" are the typical forum comments that have no informative value and cannot be proven.
Like "my cousin's nephew's friend who died two years ago heard something in a pub..."
I used to have a Gtir and we bought this 4CW crank from this zedperformance three years ago. We dyno tested it and we reached 421 BHP. I was using that car until I sold it 3 months ago. I had no issues with that 4CW crank whatsoever and nothing's been bent.
I couldn't find any bad opinions of those 4CW cranks and I would appreciate green_rs13 if you can point me at the right direction where you read that. I would be interested in it too but as I said earlier I was using my RNN14 for quite a long time without a worry.
It all depends what you buy and what you expect from it. By my opinion a well balanced stock crank can do 400HP easily. No need for high spec crank but 650 BHP... I think that's a different level. If you want to throw that much money at your engine then 650 HP will require more than just "luck" and a stock crank.
I remember when we bought that crankshaft then we found TBK Japan logo on the packing which is a Japanese aftermarket part supplier.
Now I bought a 200SX and started to rebuild it.
For 650 BHP I wouldn't recommend that 4CW crankshaft and you may want to look at some high spec forged crankshaft. That will cost a fortune but it gives you a peace of mine.

[green_rs13]

the reason I was looking into them initially was they were physically lighter than the 8CW cranks. I was musing with the concept of buying the lighter crank then getting it lightened as a brand new super lightweight crank cant be a bad thing. think of the pickup with less mass to spin etc.. but then I figured with engineering type logic stuff that the counter weights job is to counter balance the weight and do inertia type stuff so it all must be to do with rotational mass. less weight spinning on a larger radius is the same as a greater weight on a smaller axis or something like that.

the N1 almera with the Sr16Ve came with a 4cw crank and they rev to something daft like 9k rpm. so the cranks can obviously take the revs but then those are none turbo small displacement revvy engines so wont make much torque. they also don't have a crank girdle like the RWD sr20 but were sold as track cars so they knew they were going to get battered.

the early VE engines came with the 4CW cranks but then Nissan swapped to the 8CW in the later VE engines. which I guess is where the surplus OEM cranks I was considering came from.

im sure a lot of the Sr20VE engines are mated to automatic boxes, that VET out of the 4WD off roader thing is always auto so you cant really thrash the beans out of them as they probably wont even rev past 6.5k plus they have **** cams etc.. but still have the 8cw crank.

so the facts are
anything that is low in power or old has the 4cw crank
anything that makes decent power has the 8cw crank
Nissan put the 8cw crank in the later stuff and all the 4cw cranks went on ebay

the 4cw cranks are probably fine and have probably been thrashed for years by all the aussies who buy the weird and wonderful jap imports.

[Adams]

Thanks for the input guys. As pointed out the problem is very scarce practical info on these units... Hence assumptions and logic like Green_rs13 wrote are one route we are exploring, on the other hand hard info from s14guy is much appreciated - we know now that the aftermarket 4CW crank is good for at least low 400bhp.

In general based on multiple examples the stock cranks from our cars are pretty capable. We found some good info from Mazworx and I think it's safe to say that well balanced and nominal OEM 8CW crank will be fit for the ~700 bhp level. Other thing is that we'd obviously like this engine to be as efficient and capable as possible, hence if the OEM 4CW unit would be of similar reliability as the 8CW one, benefits of the lighter one are pretty self-explanatory.
However as pointed out using an unproven part as the heart of a pretty work/cost intensive build is a significant risk, hence without good background info that won't happen. I was actually hoping that maybe someone either used them in higher hp applications or maybe has seen a project that did we could find and contact the owner/builder. No luck so far :/

Good info on the manufacturer of the zedperformance crank! When I addressed them directly they informed me that it's not a crank that would be suitable for other applications than stock power levels, however as mentioned above they seem to work! (guess the shop wants to play it safe)