Profiling cams
Now now, it's not BETA testing software at all, it's simply whether they want the general public access to those tables/settings (just had that very email exchange with Roy again last week or so, lol)
Its a couple of settings, not rocket science
...although how to use them for best results is maybe open to discussion
Its a couple of settings, not rocket science
...although how to use them for best results is maybe open to discussion
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Seasoned HDF Member
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From: poway
Very cool Bruce, I was following on the other forum when you built this. I know when I degree cams they are rarely dead on with the cam card. I'm not sure if that is due to manufacturing or on purpose. It seams like casm that come from the manufacturer (i.e. Andrews) are usually closer to the advertised specs than cams from a vendor (i.e. S&S). A device such as yours would be very helpful for tuning. Power Vision has IVC and IVO setting that are available for those of us that have BETA testing software. When you get the right setting in it can bring the idle kpa down lower which gives us a lot more usable ares of the MAP to adjust. TTS has the ability through the cam analyzer.
The main purpose of this profiler is to look at cam ramps.. My interest lies in cam noise and ramps.. When I did the original version, I used the cam info to feed into simulators. The simulators could show some of the details but it was easy to add velocity, acceleration, and jerk to the software..
Unfortunately this device does not do a good job of verifying cam timing as far as advance and retard.. It uses a reference point to do the calcs. Open or close events or TDC lift specs.. The best way to validate overall event timing is to check in the motor that the cam is going into. That way things like chain stretch and other manufacturing tolerances on gears, lifter position, etc an be included..
The main purpose of this profiler is to look at cam ramps.. My interest lies in cam noise and ramps.. When I did the original version, I used the cam info to feed into simulators. The simulators could show some of the details but it was easy to add velocity, acceleration, and jerk to the software..
The main purpose of this profiler is to look at cam ramps.. My interest lies in cam noise and ramps.. When I did the original version, I used the cam info to feed into simulators. The simulators could show some of the details but it was easy to add velocity, acceleration, and jerk to the software..
I agree that the best way to measure timing events is with the cam installed. I'm not going to say I degree every cam I put in but i do on a fair amount of them. Just depends on the build.
Last edited by Wide Open Cycles; May 23, 2017 at 06:58 PM.
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,830
Likes: 7,968
From: poway
very cool. So have you found "noisy" cams to have "steeper" ramps? Take Woods grinds for example. I like the power they make but as a shop owner I won't use them. (Unless specifically requested by a customer). Its hard to explain to someone that just spent a good amount of hard earned money that the valve train noise is normal with the cams. I attribute the noise to the cams slamming the valve open and then slamming it shut. Its more a theory i guess because i have no way to back it up. Your device seams like it would be perfect for that.
I agree that the best way to measure timing events is with the cam installed. I'm not going to say I degree every cam I put in but i do on a fair amount of them. Just depends on the build.
I agree that the best way to measure timing events is with the cam installed. I'm not going to say I degree every cam I put in but i do on a fair amount of them. Just depends on the build.
Here is a pic of the H290 (White) /Tw55 (gray).
Top graph has been blown up to show valve set-down ramps. Notice the TW55 has about 0.004 higher lift on the gentle part of the ramp.. The TW55 will certainly be quieter than the H290. (it is so far).
It's not really steeper ramps that make them noisy but how the valves are lifted and dropped back on the seat. (you mention that) Most important is dropping... Lifter bleed is the issue. All lifters bleed from start of valve lift to valve set down. How much? I'd guess 2-5 thou would be typical (Discussion below), A heavy valve springs, heating the oil (make it thinner) can increase bleed rate.. Running at higher R cam keep the lifter from covering and taking up lash for the next lifting of the valve.
Here is a pic of the H290 (White) /Tw55 (gray).
Here is a pic of the H290 (White) /Tw55 (gray).
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