I got the English cam cards from Toda for their A, B, and C spec cams so I'm posting them here for easy access and discussion.
I've listed both the cam specifications from the cam cards, as well as my measured lift and duration where applicable. For my measurements, cams were installed in a cylinder head, valve lash was set to 0.004" to simulate hot running clearance, and swept 1 degree at a time with a dial indicator on the valve to measure lift.
If you've got any of these cams in your car please let us know your thoughts and dyno results.
Here's the short of it (VTEC lobe only), duration is from 1mm/0.040in lift.
Factory M/T
Intake spec: 230° duration, 10.20mm/0.402" lift
Exhaust spec: 225° duration, 9.00mm/0.354" lift
Intake measured: 228° duration, 9.98mm/0.393" lift
Exhaust measured: TBD
Toda Spec A 285/280
Intake spec: 245° duration, 12mm/0.472" lift
Exhaust spec: 240° duration, 12mm/0.472" lift
Intake measured: 238° duration, 11.8mm/0.465" lift
Exhaust measured: TBD
Toda Spec B 295/285
Intake spec: 255° duration, 12mm/0.472" lift
Exhaust spec: 245° duration, 12mm/0.472" lift
No measurement data.
Toda Spec C 295/295
Intake spec: 255° duration, 12.5mm/0.492" lift
Exhaust spec: 255° duration, 12.5mm/0.492" lift
Intake measured: 252° duration, 12.42mm/0.489" lift
Exhaust measured: not available
Comptech
Intake spec: 256° duration, 11.43mm/0.450" lift
Exhaust spec: 251° duration, 10.92mm/0.430" lift
Intake measured: 244° duration, 11.07mm/0.436" lift
Exhaust measured: TBD
Web Cams Regrind Profile
Intake spec: 235° duration, 10.20mm/0.410" lift
Exhaust spec: 230° duration, 9.65mm/0.380" lift
This is grind #766 from Web Camshafts. Last time I checked Web doesn't advertise this profile but they do have it available if you ask. I've heard people say good things about using these on boosted engines which based on the fairly conservative specs and fairly wide lobe separation is what I assume these are meant for.
Measurements, Charts, and Discussion
This is where it gets really interesting. I measured the lift vs camshaft rotation for the cams I had available to me to see how the numbers stack up against what was advertised. I only have intake cam data now but will add exhaust cam data as I have time. I set valve clearance at 0.004" to try to simulate hot running clearance, installed a degree wheel on the camshaft and a pointer on the head, and used a dial indicator to measure valve lift in 1 degree increments.
This first plot shows the overall differences between each of the measured cam profiles. I adjusted the phase of each cam so that they all hit 1mm lift at the same point on the graph so its easier to visualize the differences in duration. Most of this looks about how you'd expect, but what's interesting is the CT profile has the largest advertised duration but actually has substantially less than Toda C. Toda A also ramps open and closed faster than CT so despite the lower duration at 1mm will likely allow greater air flow.
As far as discrepancies between the specs and measurements go, a lot of specs are listed at zero clearance, which isn't realistic or feasible, which is why I opted to use a clearance of 0.004".
I also plotted only the low lift areas so we can easily see the differences in how the cams open.
At some point in the next few weeks I'll take measurements for the exhaust cams as well and edit them into this post.
I've listed both the cam specifications from the cam cards, as well as my measured lift and duration where applicable. For my measurements, cams were installed in a cylinder head, valve lash was set to 0.004" to simulate hot running clearance, and swept 1 degree at a time with a dial indicator on the valve to measure lift.
If you've got any of these cams in your car please let us know your thoughts and dyno results.
Here's the short of it (VTEC lobe only), duration is from 1mm/0.040in lift.
Factory M/T
Intake spec: 230° duration, 10.20mm/0.402" lift
Exhaust spec: 225° duration, 9.00mm/0.354" lift
Intake measured: 228° duration, 9.98mm/0.393" lift
Exhaust measured: TBD
Toda Spec A 285/280
Intake spec: 245° duration, 12mm/0.472" lift
Exhaust spec: 240° duration, 12mm/0.472" lift
Intake measured: 238° duration, 11.8mm/0.465" lift
Exhaust measured: TBD
Toda Spec B 295/285
Intake spec: 255° duration, 12mm/0.472" lift
Exhaust spec: 245° duration, 12mm/0.472" lift
No measurement data.
Toda Spec C 295/295
Intake spec: 255° duration, 12.5mm/0.492" lift
Exhaust spec: 255° duration, 12.5mm/0.492" lift
Intake measured: 252° duration, 12.42mm/0.489" lift
Exhaust measured: not available
Comptech
Intake spec: 256° duration, 11.43mm/0.450" lift
Exhaust spec: 251° duration, 10.92mm/0.430" lift
Intake measured: 244° duration, 11.07mm/0.436" lift
Exhaust measured: TBD
Web Cams Regrind Profile
Intake spec: 235° duration, 10.20mm/0.410" lift
Exhaust spec: 230° duration, 9.65mm/0.380" lift
This is grind #766 from Web Camshafts. Last time I checked Web doesn't advertise this profile but they do have it available if you ask. I've heard people say good things about using these on boosted engines which based on the fairly conservative specs and fairly wide lobe separation is what I assume these are meant for.
Measurements, Charts, and Discussion
This is where it gets really interesting. I measured the lift vs camshaft rotation for the cams I had available to me to see how the numbers stack up against what was advertised. I only have intake cam data now but will add exhaust cam data as I have time. I set valve clearance at 0.004" to try to simulate hot running clearance, installed a degree wheel on the camshaft and a pointer on the head, and used a dial indicator to measure valve lift in 1 degree increments.
This first plot shows the overall differences between each of the measured cam profiles. I adjusted the phase of each cam so that they all hit 1mm lift at the same point on the graph so its easier to visualize the differences in duration. Most of this looks about how you'd expect, but what's interesting is the CT profile has the largest advertised duration but actually has substantially less than Toda C. Toda A also ramps open and closed faster than CT so despite the lower duration at 1mm will likely allow greater air flow.
As far as discrepancies between the specs and measurements go, a lot of specs are listed at zero clearance, which isn't realistic or feasible, which is why I opted to use a clearance of 0.004".
I also plotted only the low lift areas so we can easily see the differences in how the cams open.
At some point in the next few weeks I'll take measurements for the exhaust cams as well and edit them into this post.
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