I noticed something, on the NON-VTEC B20 motors, the torque is sick before 5,000 RPM but on the VTEC B20 motors, the torque is less considerably at that RPM...is this all because of the low profile lobes on the VTEC cam?

Because if you compare my graph, at 4,500 RPM its making a whopping 225 FT-LB :



Where as in the B20VTEC Turbo, at 4,500 RPM its making around 165 FT-LB:



Just wondering why there is a big difference in torque. Because I figured that with a VTEC head, the torque down low would be the same???

 

I'm thinking about doing a VTEC conversion in a few months but don't wanna lose all that nice torque in between 3,500 rpm and 5,500 rpm.

 

part of the reason for the torque loss is that jeff uses a really big turbo that takes a bit longer to spool than the run-of-the-mill drag stuff.

 

I'm sure the huge turbo they were using in the second graph has alot to do with it. When do you hit full boost?

 

The turbo that I am using is big as that one. Anyone?

 

the cams will have something to do with it, but what head is being used also (difference in combustion chamber size gives different compression)?
was there a change in pistons (compression or bore 84vs84.5vs85mm)?
does the other guy have his vtec engaged from off idle? bigger cams get worse vacuum at low rpm, and i also assume that the vtec head (although a great flower) is designed for optimum flow at a given rate, and if the intake is too slow then it is not being efficient.

 

Do what I am doing
2.0LS/VTEC T?? Turbo.

yeah CRV Monsters is big. But his boys in the white car is bigger ehheeh!! MY old turbo which was new when sold.