DAYUIZ

I'd like to hear why you went this way over the B20 crank. Opinions please.

daver

Well, i dunno if you'll find many people who've gone with that combo. I assume you've read up on crvtec.com? They don't recommend it 'cause of the super high extra cost of the custom rods, and crank availability (but you have one already?). Plus, having the better r/s ratio is overshadowed by losing almost 2L of cc's. So less tork (and power).

All that said, i'm sure they're interested in getting as much power for every dollar as possible. They claim that their engines have proven to handle the abuse. But if you are interested in paying more (for less power) to get some extra peace of mind, by all means.

The whole b20vtec idea, i think tho, is about the 2L tork. that's why, when i build mine, it'll definatley keep the b20 crank. But i'm not revving it past 7k. The larger cc engines seem to naturally power peak lower anyway. I'm not building a racecar here though, it'll be a daily driver, and i'll happily compromise power for longevity and fuel economy.

I just read an old article introducing the b18c1 and it claimed that the rod to crank connection was the formost limiting factor against rpms, over r/s and piston speed whatever. And they improved the gsr bearing material accordingly. What makes the high revving b20/v even scarier (over the ls/v) is the heavier pistons.

Sorry this couldn't be some experienced input (not yet), but as a fellow researcher, all i can say is the usual "rev at your own risk."

d

Project SSAP1

stick with the b20 crank..just get the bottom end balanced!!
also check out this site..im doin the same project now and this helped me out a lot..also when doin this project the best thing to do is get all the parts first...and DONT...I REAPEAT DONT cut n e corners. while ur at it..get all new gaskets, and dont forget to get the head opened up to match the block...this setup is gonna cost some doe..so far i cost me like $3400 for just the block and all its parts..oh yeah i did get the block sleeved..so thats the part that cost the most..and finding all new oem b20 parts sucks ***..but i cant wait to get my new beast on the streets...
http://www.crvtec.com

DAYUIZ

Well thanks you guys for your replies. I have read up on both of those sites but was wondering if anyone was using the B17 crank. I think my anticipation to rev my built B17 motor has just warped my thinking into making me want to rev my B20 as well.

From all the replies I've gotten, I'm pretty sure I'll go with the B20 crank. I've always been hung up on the whole R/S ratio deal, but the more I read, the more I find its not as big a deal as I thought it was.

I realize its going to cost a lot. I am ready for that because I've seen to many cost cutting projects fail later and cost more in the end. I guess my research now needs to focus on what parts to buy and where to buy them from.

While I'm at it, since my B20 block already has GEM sleeves in it, does anyone have anything negative to say about boring it out to 85mm just for that little bit of extra displacement? I mean, I have to get custom pistons anyway, so why not right?

Thanks again you guys.
-Steve

daver

here's a question that i havn't had answered yet. They say its good to widen up the combustion chambers to deshroud the valves in the crvtec setup, but. Isn't the head gasket the same as the ls one? And is it an 81mm head gasket? My reasoning is, if you widen the comb chamber to match the cylinder dia., wouldn't a narrower head gasket destroy the effects? Or not?

d

ATYPR

the headgaskets are not the same

daver

so the crv uses a larger dia head gasket to match the bigger cylinders????

d

jonsteR

I belive mike k from this board has done the b20vtec with b17a crank and was making flat 150lbs torque thoughout. I'll try to find it.

jonsteR

Here's what i've found...
https://honda-tech.com/zerothread?id=116473
https://honda-tech.com/zerothread?id=118876

HTH

DAYUIZ

JonsteR is my hero......High on bounce or not!!!

2simplex

i thought the headgasket would be the same as an LS because the b20's share the exact same head as the b18b's??