B18C6 frankenstein b20?

[dc2paul]

Hi all,

I was just wondering what your thoughts are on my idea? I have a ukdm dc2 type-r with a b18c6, my crankshaft is wrecked and i was thinking about getting a b20b3 crv engine and making a b20 vtec with my b18c6 head etc.

i am thinking of this because i can get a b20 for way less than a crank and rods

What are the pros and cons to this performance wise? would you recommend it? any advice greatly appreciated! Thanks!

 

[phunky.buddha]

You get a slightly longer stroke- no major drawbacks if you build it correctly. I ran a B18A/B crank in my GSR block. If you can keep the GSR block and resleeve (if you're willing to fork out the cash) it's a good option. The B20 block is a good idea too- I ran two builds with a B20 bottom end. Upgrade the pistons and rods- especially since you're going to be inside the engine anyway.

 

[dc2paul]

cheers buddy, just phoned my local dismantlers and they have a b20b3 complete 60k miles £350!! a steal!

 

[FLounder]

you really need to upgrade the internals though if you plan on revving to 8k+ rpms. the b20 rod bolts are known to be a weak point and dont like high revs. ideally, some new pistons would be nice too, because the b20 bottom will give you a lower compression ratio in stock form.

 

[dc2paul]

yeah been looking at wiseco pistons and eagle h-beam rods, arp main bolts, head studs and rod bolts, block guard, and acl race bearings. this would surely be a strong bottom end?? was thinking on using wiseco piston kit K594M84 with comp 13.2:1- 14.2:1? also would the girdle from my gsr block fit the b20 or do i need to buy an aftermarket one? And which timing belt kit do i need, still b18c?

Thanks Paul

 

[FLounder]

sounds pretty good, but the compression is very high. you will need high octane gas for a CR over 13:1. also some big cams to feed it. for a street car 11.5-12.5 is a better area to shoot for i would think. i dont really think that a block guard will be necessary, it seems block guards can affect the cooling and arent worth the risk on an all-motor build. you arent going to be putting the cylinders under that much abuse. yes, the b18c timing belt will work.

 

[phunky.buddha]

I don't think the girdle bolts right up- something about a different shape on the main caps. It's been a long time for me- I just know that I went with a sleeved GSR block instead of trying to adapt the main caps to my B20 block. Aftermarket girdles aren't that much though.

13:1 is about the highest I would go on pump gas, and that's only if you have a really good tuner and some really huge cams to help bleed off the compression through overlap.