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Ok, major update time. I couldn't leave it alone knowing I was so close on the tune, so I called Daniel at Simple Quick to schedule some more dyno time. The first dyno session had a couple of problems - one bieng what appeared to be a minor oil leak, the other bieng a much more serious problem - leaning out at an instant, at somewhere near 7,000RPM.
There were four definitive problems in the fuel delivery
1) The diaphragm on the billet boost referenced power valves was not fastened tight enough to the valve itself.. it leaked fuel to the back of the power valve (and out the external vent for the BRPV).
2) The power valve gasket itself was apparently leaking as well.
3) The primary powervalve's valve was not seating 100%
4) The power valve restrictor channel was simply too small....
All of that was fixed first, along with the oil leak - bad fitting install by yours truly.
The base timing on the crank trigger was set at 30* instead of the 40* that I normally tune from. (this engine was ran N/A for about 5 miles, so it was set at a 'normal' number). This meant that there was a 10* discrepency in the total timing at full boost. I was actually running 10* less than I thought. Between the corrected timing and the BRPV fix - it picked up about 40HP through the curve.
All in all, todays dyno session was 100% successfull - but I'm still going to work on the powervalve arrangement, I want some more fuel in it without increasing main jet sizing (right now running 74/74). The pvrc's are in the .100 range.
(most of that stuff won't make sense who's not pretty familiar with the innards of a Holley, but you get the idea)
The last 'problem' was to keep it from spinning the tires on the rollers. The only way I could get it to do that was to roll into the gas for what seemed like an eternity. If you watch the carb linkage in the video - you'll see what I mean. Long story short, it made right at 780ish on the spring and turned up it made 922RWHP. I had a goal of 950, but this is close enough for now. This was on 16.5* timing @ 26psi. This turbo is spent now.
Now, it's time for the rest of the build - the cage, TTSFC's and wiring.
Enjoy.
There were four definitive problems in the fuel delivery
1) The diaphragm on the billet boost referenced power valves was not fastened tight enough to the valve itself.. it leaked fuel to the back of the power valve (and out the external vent for the BRPV).
2) The power valve gasket itself was apparently leaking as well.
3) The primary powervalve's valve was not seating 100%
4) The power valve restrictor channel was simply too small....
All of that was fixed first, along with the oil leak - bad fitting install by yours truly.
The base timing on the crank trigger was set at 30* instead of the 40* that I normally tune from. (this engine was ran N/A for about 5 miles, so it was set at a 'normal' number). This meant that there was a 10* discrepency in the total timing at full boost. I was actually running 10* less than I thought. Between the corrected timing and the BRPV fix - it picked up about 40HP through the curve.
All in all, todays dyno session was 100% successfull - but I'm still going to work on the powervalve arrangement, I want some more fuel in it without increasing main jet sizing (right now running 74/74). The pvrc's are in the .100 range.
(most of that stuff won't make sense who's not pretty familiar with the innards of a Holley, but you get the idea)
The last 'problem' was to keep it from spinning the tires on the rollers. The only way I could get it to do that was to roll into the gas for what seemed like an eternity. If you watch the carb linkage in the video - you'll see what I mean. Long story short, it made right at 780ish on the spring and turned up it made 922RWHP. I had a goal of 950, but this is close enough for now. This was on 16.5* timing @ 26psi. This turbo is spent now.
Now, it's time for the rest of the build - the cage, TTSFC's and wiring.
Enjoy.
Hello Chris and Greg.
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