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Discussion Starter · #1 ·
The VW stuff is still on hold for now pending the judges decision. He still is pouring through the documents and wont have a ruling probably until sometime next week, hopefully. In the interim, I plan to pick up a car tommorrow to prep for testing once i do get the prototypes.
Here's some stuff thought you guys may be interested in.
A set of Smart Valves were contracted for a particular race team campaining in Winston Cup Series. The motors used are V8 pushrod, runnning cams with etreme lift and duration (around .650" and 305 degrees or thereabouts). The test motor was set up on a machine that tests valvetrain and reciprocating parts durability. Since the team expects parts to go broke, this is oneof the way that they get an idea of what they can get away with. There was no dyno run conducted as far as I am aware, so the engine did not actually start and run through any combustion events.
The machine use an electric motor to spin the crank, which in turn puts the parts through their paces. Using variying speeds, the motor was spun through tthe entire rpm band. There was a 10 degree difference between the floating seat angle of the Smart Valves and the fixed valve seat.
The motor was spun for a maximum of 20 minutes at high rpm before the Smart Valves floating seat went into failure- splitting into 2 seperate rings.
Since the motor did not go through any real 4 cycle events, inertia did have an effect on durability of the floating seat. What makes the seat work is pressure differential, of which there was none. Add to the fact the floating seat and the fixed seat were at different angle cuts, created the effect of the valve banging the floating seat against te fixed one. Without any pressure (air, fuel or exhaust gas) to buffer the floating seat movement, the main valve simply cleaved the floating seat into 2 sections.
It is believed that had the motor gone through an actual 4 cycle event- intake, compression, combustion, and exhaust, that the Smart Valve would have lasted agreat deal longer, even with the 10 degree difference in flaoting seat and fixed seat angles. If the floating seat and fixed seat angles were properly matched, there would be no failure.So now we know that there are limits to what the Smart valve can tolerate, under peculiar circumstances.
The next series of tests will be conducted both on a dyno, and on the track with the motor going through its expected cycles. This is when we expect to see the first hard numbers related to performance.



[Modified by aatap, 12:57 AM 4-10-2002]
 

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Re: VVT projects (aatap)

Awesome! I read a post on this a while ago and thought the idea was great but passed it off with semi-skepticism, but I just checked your web-site and I'm impressed with the ingenuity and simplicity of these valves, screw those kangaroo kourt dorks, I can't wait to try these in my cars http://****************.com/smile/emthup.gif
 

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Discussion Starter · #3 ·
Re: VVT projects (i81b4u)

http://****************.com/smile/emthup.gif
Me and the designer were discussing the NASCAR debacle yesterday. We both got a big chuckle out of it. We're still trying to figure out exactly what they hoped to accomplish by running such a test. Either the engine builders didn't check to see that all the specs were correct, or they knew and tried the parts out anyway. There is no way you can expect these parts (let alone regular valves) to survive when the car is running extreme cams, extreme springs, and odd clearances between the valve and the seat. I guess thats how some of the NASCAR boys do things.....

I guess it says that the Smart Valves are pretty tough- even in the hands of really "smart" people
 

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Re: VVT projects (aatap)

Well, they were just testing them to see how they performed under odd circumstances. You should see some of the things we used to do to the shocks on our Class 7s desert race truck. Strange things caused them to fail but we were able to learn and design a better suspension setup. Now, we didn't operate them without all the factors needed for them to work right, so we got the shocks to fail under "normal" operating motions. This doesn't seem like a very fair test of the Smart Valves mainly because the required operating conditions weren't met. Maybe they were just trying to be safe in case the motor exploded or something. Who knows? Thats why everyone switches away from The Speed Channel whenever NASCAR comes on.
-edit- Corrected spelling


[Modified by Clean97GTi, 11:30 AM 4-10-2002]
 

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Discussion Starter · #5 ·
Re: VVT projects (Clean97GTi)

Well, I understand the logic behind spinning up the motor, but running the different angle cuts was the really big problem. I think the Smart Valve would have lasted several hours if the fixed and floating seats were properly matched, even if there were no active 4 cycle events as a buffer. But we did learn that the material used was pretty good in terms of durability. 20 mins. is a long time for something like this to finally break.
I don't think the team will try that particular test again, though.
 
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