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ZODIAC · Joined: 08 Apr 2009 Posts: 342 Location: West Haven, Ct

would a GT style, forward facing hood scoop let in too much rain/snow with a carburated set-up? for those that dont know, i have a holey 2bbl carb with a rear facing cowl scoop currently. i want to change that look and make it more functional. i have plenty of time (at least 6 months) before this is a real issue, but just trying to plan ahead.
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"Kraut cars, they know how to build 'em".
1977 924 N/A - Red with waterdamage interior
yes...waterdamage is now a color...

Martijnus · Joined: 29 Dec 2006 Posts: 2019 Location: Netherlands

why do you think facing it forward would make it more functional?

Have you considered that the pressure caused by that could interfere with the flow through the cooling radiator?
I'm not saying that will happen, but it could....

If you do mount a scoop that way, it would be interesting to see if you notice a difference in temperature.
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"Rule: Turbo's make torque, and torque makes fun." (C. Bell)

924 "50-jahre", 1981.
MSII/extra, LPG, ITB's, 5lug.
To be turbo'ed in a while.
Killed her at the Nurburgring, Porscheless at the moment

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Time to drag out the ol' pressure differential chart again:

Your cowl induction setup may actually be quite functional. If you look at the chart above, "valleys" in the graph represent areas of high pressure, and you can see that at around points 20-22 there is high pressure. This is how the fresh air vent gets it's source of air. With the cowl induction scoop that came on the car, it is quite likely that air is being sucked under the hood as well. This is why many american muscle cars have cowl induction setups.

By contrast, if you put a CGT scoop forward on the hood, you can see that most of the locations where you would put it are low pressure zones. You will get some ram air effect forcing air in, I'm sure, but it's certainly not an ideal location.

If you're really worried about routing cool air to the carbs, make a plenum with a snorkel routed so that it picks up air from the front of the car. You could even get a stock alternator snorkel and attach tubing to it.

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erstwhile owner of just about every 924 variant ever made