HYBRID Vtec

I see a lot of questions about LS/VTEC and Minime floating around right now, and it seems like a lot of people are confused. There is no "LS/VTEC" engine, or a "Minime" engine. Both are essentially the same, a non-vtec block with a vtec head.

LS/VTEC
The LS/VTEC gets its name from the Acura Integra "LS" block (b18a1 or b18b, from any non-GSR and non-type-r Integra) and any b-series VTEC head. Most of the time, a b16 head is used on either b18 LS block because of its flow and excellent documentation.

There are a few reasons LS/VTEC rocks, but most importantly it's the stroke ratio, which nets awesome torque (for a Honda) which equates to awesome power. LS/VTEC builds can put out even more power than ITR (Integra Type R) engines do, because the crank creates a longer stroke and produces more power.

However, that stroke comes at a cost. Because the stroke is longer (meaning the piston travels farther vertically in one rotation), more pressure is put on the block sleeves. It theoretically cuts down on the longevity of the engine. There are plenty of people out there who have had no problems for umpteen miles on an LS/VTEC build, but they're the lucky ones. The same motor with a more ideal rod to stroke ratio (such as the near-perfect 1.74:1 of the b16a1) would last longer than an LS/VTEC. Unfortunately, a 1.8l Honda motor with such a rod to stroke ratio does not yet exist... Read on.

MINIMe
Minime engines are basically the cheap way to make more power than stock. You take your existing 1991 CRX Si (which you already updated your car to if you haven't already), remove the head, and insert a vtec d-series head onto it. Some applications may get as much as 30hp gains, and because d-series motors are so common this could be a free upgrade. The next time you're at a salvage yard, check to see if they have a d16z6 or d16y8 head in-stock, and how much it would cost for that and the ECU. You'll only have to add a way to activate the new vtec you've installed.

CR-VTEC
This one has kind of a special place in my heart. The CRV comes with a big girthy B20Z block, and throwing a b16 head on there and voila! There's a CR-VTEC motor.

Now, back to the rod-stroke ratio, a de-stroked B20Z could certainly be engineered to be damned close to the ideal 1.75:1 rod-stroke ratio. THAT, my friends, is what I want. Vtec or not, that would be the nasty-scary-k20-killer that everybody has been dreaming of. You just didn't know that's what was under the hood in your dreams.

VTEC
Personally, I say that vtec is a waste of time. It has no performance application, and is more expensive than it's really worth from a daily driver perspective. I'm also a big fan of simplicity, and a strong non-vtec build is what I consider to be ideal. A nice cam job and a tune can breathe new life into a car that's starting to feel less exciting.

For further reading, see:
LS/VTEC