Bit of advice, put the B20 on a engine stand, build it untill your done with it, then swap it in. Leave the stock crank in it and use clevite berrings throughout, arp studs where you can. Get aluminum balanced rods, aluminum pistons(I'd stay 11 to 1 c/r or lower), use a golden eagle ls/vtec conversion kit, a B16 head(this is going to be the kicker, a B16 head is by far going to be the power maker). Use a B16, edlebrock, or skunk 2 intake manifold(a ported B16 IM would actually do the job very well)

I'd also use a GSR trans with a quaife lsd(pricey but worth it).

I cant stress enough to build it now though, you said your z6 is running great so why take it out and hurry the whole thing. I know you want more power, I know your tired of being slow. But do not let that get in the way of doing the smart thing.........build it out of the car, leave your stock Z6 in, put it all in when you have everything done. No downtime and a well thought out, quick swap make it so much less likely to **** you off enough to throw a brick through the window.....

 

^ I do agree, I am looking at parts for the whole thing right now and figuring out the costs. Id like to get the bottom end in and set before anything, and I am going to buy a girdle for it too. Im thinking about the waste of money if I toss this engine in and have to buy a obd2 harness and ecu only to pull it out when I get a vtec head.

Why use the stock crank? Its not balanced you know.

Aluminum pistons, is this for the light weight factor?

As for the LSD, I can get a good deal on a Type-R LSD.

 

The stock crank because that is the whole point of a ls-cr/vtec. The long stroke, you can overbore any B series to accomodate B20(or slightly over sized B20 pistons) but the stroke is what makes these 2 builds worth it. Plus honda b and d series cranks are forged and you can have a stock crank balanced. Also the reasoning behind lightweight pistons(good quality though) is like you said weight, reducing internal mass is a big "to do" on a N/A engine as it will inprove throttle response and make the engine "snappy" or quick to rev. A DC2 lsd will work fine but I say gsr because it has gearing better than say a Y8/Z6 transmission but it will not slap you in the face with high rpms at highway speeds which make for worse milage and overall more wear on the engine.

The biggest thing about the build you are doing is balance, you need to keep weight down as much as you can but it has to be balance correctly or it will be a liability to rev the bottom end to the area of the powerband inwhich the head is going to shine at. Your talking piston speeds of like 4700 feet per minute(around 78 feet per second) so you better be sure it is balanced correctly along with having good berrings and good studs/fasteners to hold it all together.

 

Looks great man. I just want to sy that you guys are super cool and love to spread information around which is one thing i love about this forum. Im going to keep an eye on this thread as i want to swap in a better motor in my car but no go boost since its an auto and i dont want to explode my tranny.

I was thinking on of these b20's would work nice in my car and will love the information that im bound to gain from this thread.

 

just take the crank to a machine shop and have them spin balance it and polish it, its like uder $200 and its balanced up to 10,000 usualy

 

^ that sounds good but in the end its still 34lbs right. I like the idea of the Eagle 27lb crank, although it will cost an arm and a leg.

 

If your buying a eagle crank you are totally neglecting the reasoning behind using a LS/CRV block. You could have bought a obd0b16 for like $900 including the trans, and slapped that crank in it along with oversized pistons and you would allready have the good head plus oil squirters to douse the botom of the pistons with oil to keep them cooler. Sounds great loosing 34lbs through your crank but you can make up for that elsewhere like in rim selection, lighter flywheel, the balancing will play a big factor in it also.

But suite yourself.

 

you can have the machine shop machine some weight off your stock crank to lighten it up

 

Ill look into the shop and see what they can do for me

Marty, the aftermarket crank is the same as the stock one sept that its balanced and lighter. Same stroke. I thought of stroking out a B16 and I dont like the idea.