Quote:
Originally Posted by DrewZ28
Old thread, but did you swap all 4 cams from a 3vz-fe or just the exhaust cams? I'm researching this swap now.
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You swap all 4. If you did only exhaust, the valve timing would be thrown off and you might have too much overlap (exhaust open before ignition completes) which will result in a loss of power, not a gain.
This swap is about taking cams from a higher revving engine that makes power on the top end and trading it for power on the bottom end. This is just the stock stats for the engines and how they are tuned:
3VZ-FE: 188 HP at 5200 rpm and 203 lb⋅ft at 4400 rpm
5VZ-FE: 183 HP at 4800 rpm and 217 lb⋅ft at 3600 rpm
Looking at the two engines, you might say the are almost identical in power output. But let me ask you this, how much time do you drive your 4Runner over 5000 RPM's, let alone 4000 RPM's? A torque curve that comes in faster, in the 3000's is better than one that comes in the 4000's. Torque is what you feel on the road, HP is just a multiplier of torque, (RPM * TQ) / 5252. Even I don't spend that much time over 3600 RPM's.
This is why the 3VZ-FE camshaft swap has little to gain but much to lose. You'll gain a bit of HP up high but you're losing TQ where you use it the most everyday. I'm one of the few that has swapped out cams, and it cost me and engine but hey, learned something new.