dyno day for the demon

furrystump said

Carb might be on the small side, on my 408 I have run a BG 825 mighty demon which tend to flow bigger than other carbs of same cfm and am currently running 800 cfm eddy thunder. Not that you need it for you intended purpose, but it could be what is hurting you number.

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OK folks. Back to a different dyno shop today. They brought in a mechanic who likes to work on cars with carbs. First thing he noticed when he pulled a baseline run was the car was running too lean. This time the tranny is full. He then proceeded to check the timing. He pulled the number one plug and used the insert tool to bring the number one up on tdc and then checked my balancer to see if the balancer which had the timing marks scored into it from the factory. They were right on. He thought they may have been off because he checked the engine with a timing light and the previous dyno person had my total timing set at 50 degrees? So he reset the timing and did another pull and the torque went way up from 353 to 519. Then he opened both of the holley 750 carb metering blocks and up the front jetting from 70 to 72 and the rear from 80 to 82. Last pull was 353 HP and 523 torque. He also told me that his dyno is a Mustang Dynamometer and he said the readings are generally on the low side if you ask around. I am generally much happier than the first attempt to get this car dialed in. I told him I asked Mike from MRL to build me a nice street stroker and he told me that is exactly what I have. Idles real nice. Runs real smooth, and goes like hell in that 3-4K RPM range. Now I have to build a custom shroud to keep it from running warm on 90 degree days. He also told me if I wanted to up the HP that I should lose the Performer RPM manifold and install a single plane job? But I am really happy with this build as a nice cruiser.