have questions building a b20 vtec

[atomik DA]

Hi i am currently building a cr-vtec bought a new b20b bottom end ,well semi new anyway just wanted to know if i have to change the bearings on the block just to make it a bit more reliable?. Also putting it with a b16 head ,with stock bearings will i be able to go pass the b20b rev limit ? or should i just up grade the bearings just to rev a bit higher?. would really appreciate your comments :roll:

 

[Aussie]

The bearings aren't going to make a big difference on how high you can safely rev. Balancing everything in the bottom end would be the most important thing. After that it just depends on how strong your rods are, stock rods start to stretch pretty bad after 9k rpms.

 

[Tam4511]

thats essentially the same thing as a ls/vtec which is retarted unless you want to upgrade internals. you'l need upgrade rods, pistons, and sleeve the block if you want full revng potential

 

[BigMac88]

thats essentially the same thing as a ls/vtec which is retarted unless you want to upgrade internals. you'l need upgrade rods, pistons, and sleeve the block if you want full revng potential

Sleeving the block is not really necessary for an all-motor application and it doesn't effect the RPM potential (unless you're building an F1 motor that revs to 17 grand).

OP, pushing the stock bottom end to 8 would be the absolute limit and that may even be pushing it IMO. To get the most out of the VTEC head you'll want some higher compression pistons and you need to have the rotating assembly balanced to a specific RPM load. You may be able to swap rods and pistons from a B18C but you'd have to get the rods machined to the right length, and you still worry about balancing it all.

If you're running the stock low-comp bottom end, you really won't be using the head to nearly its full potential - even if you run the stock bottom end higher than normal.

 

[g3teg97]

The rod bolts on LS's are the weakest point. I would imagine the B20's are similar.

 

[atomik DA]

cool thanks for the info guys do you know of any site that might have one peice headlights for sale ?