All-Acura - LS VTEC: An introduction

I've said it a thousand times, the LS motor can be the beginnings of a powerful street machine. Just because you don't have VTEC from the factory doesn't mean you can't have VTEC. If you are not entirely certain of the process or have the experience, please contact your local machine shop to do the work

What is an LS/VTEC?
A short-block consisting of either a B18A or B18B combined with a VTEC head from a B16A, B17A, or B18C motor. It still is essentially an LS motor, but with performance worthy of the name VTEC. Basically a B18A or B18B has tons of low end power to get you off the line in a hurry. Unfortunately, the LS motor suffers from diminishing returns in the higher rpm range due to cam limitations and lose of air flow efficiency. On the other hand, the B16A is lacking in the low end power side, but once VTEC kicks in it's all over. As you can imagine it wasn't long before someone had the foresight of vision to combine the best of both motors and thus the LS/VTEC was born, with all the low-end power of the LS motor and the top-end power of the VTEC head.

LS/VTEC Advantages

B18A and B bottom-end has longer stroke thus capable of generating better torque response than VTEC bottom-ends.
B18A or B top-end has port and cam limitations to produce high-end horsepower, although B18 B is slightly better.
Aftermarket cams for B18A and B are reground cams, notorious for accelerated wear on top-end components. Cams for VTEC heads are of much higher quality.
With LS-VTEC conversion smooth idle is maintained while flat torque and high-end horsepower is maximized.
Availability of factory performance parts for VTEC top-end is more readily available: Type-R cams, manifolds, and other components.

Disadvantages.

Require complete engine overhaul for installation.
Rev limitation similar to B18A or B.
Increased lubrication (oil) needs

Note: The B16A intake manifold flows better than the B18A intake manifold.