• Protip: Profile posts are public! Use Conversations to message other members privately. Everyone can see the content of a profile post.

Camshaft Specs and Measurements (Toda, Comptech)

Joined
30 October 2016
Messages
1,113
Location
Austin, TX
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".

camliftall.JPG

I also plotted only the low lift areas so we can easily see the differences in how the cams open.

camopen.JPG

At some point in the next few weeks I'll take measurements for the exhaust cams as well and edit them into this post.
 

Attachments

  • Spec_A_EX.pdf
    150.1 KB · Views: 13
  • Spec_A_IN.pdf
    150.2 KB · Views: 8
  • Spec_B_EX.pdf
    149.4 KB · Views: 4
  • Spec_B_IN.pdf
    148.7 KB · Views: 4
  • Spec_C_EX.pdf
    148.5 KB · Views: 4
  • Spec_C_IN.pdf
    148.8 KB · Views: 5
  • comptech.jpg
    comptech.jpg
    48.1 KB · Views: 24
  • web.JPG
    web.JPG
    65.1 KB · Views: 28
Last edited:
I have the spec b cams, going to go with larger intake valves, 12:0 83mm bore compression. I already have some itb kit. I'm hoping it will put down north of 350. Right now with stock engine it put down 292.
 
Back
Top