[s-cars] A Lesson in Happersizing

[CaptMagu at aol.com]

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s-heads

Just to prove to you guys that Hap and Mike are not sitting by twiddling our
thumbs, I thought I would post an update on the progress of my car's
continuing search for more go. I just received and installed a Happersized Throttle
Body. What, you might ask is a Happersized TB? Well Dave Jones loaned me an AAN
TB and off it went to Big Bore Throttle Bodies in Redondo Beach CA. Big Ed
Mazula after receiving the TB and consulting me proceeded to give it a 1.21 mm
machining. He replaced the throttle plate with an appropriately sized new one
with out the infamous Audi/VW ramp. He had assured me that he had done this many
times with no adverse characteristics.

Now for some higher math. Old TB diam.-67.81mm = 3609.05sq mm surface area.
New TB diam.-69.02mm = 3739.55sq mm. Not bad Hap but that's only about a 3.6%
increase. Yes my friends but we also removed that nasty ramp. The best I can
figure that ramp is good for about 762.86 sq mm. Now we're talking a further
reduction of the original Old TB surface area by this 762.86 which gives us
2848.19 sq mm. We also have to factor in the throttle plate shaft and that works
out to 414sq mm. Throw all that into a math mixer and you get about a 17%
increase to TB surface area. Not bad for an evening's work.

How does it run you say? I think that it actually runs better. Throttle
response and idle transition going up and down are smoother. One of the reasons I
am persuing this avenue has to do with compressor surging that those of us with
larger turbos have to deal with. There was a dramatic reduction in the surge
and the only time I could really feel it was when I was loading the turbo
coming up a good grade in 5th or 6th. As I backed off the throttle with the clutch
engaged the surge could be felt but at a much reduced level. My next step is
a ported intake manifold with some major surgery. It will also be polished
inside and out;-)

Is it true that Mike Pederson is unleashing the fury of spaghetti? Whats dat
you say Pizzo? Well folks stay tuned, same Everboost time, same Everboost
channel.

Hap, livin on dah edge in Everboost, Maguire