Cold air plenum for carbs

61Klassic

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Hi everyone.
I have a model A roadster with a full hood, running a healthy 293” flathead underneath with 3 97’s on a straight linkage.
The under hood temp can really get hot, surely sucking all this hot air into the engine can be no good for power?! However I’ve seen very few pics of lakes racers of old trying to scoop in cold air.
How would Stromberg 97’s deal with having a common plenum and having air forced in at speed?
I’m running a/f ratio meter so could monitor any lean conditions.

After any advice, thoughts?
 
Having a common plenum and the outside air forced in at speed would work fine. However if you were able to go REALLY fast then the forced now ram air would create a lean condition. This lean condition would crate more heat and possibly damage some internal parts if the top end charge was for an extended amount of time. The REALLY fast speed would be anything over 120 MPH the now ram air could add a slight amount of inlet pressure.
Ronnieroadster
 
Thanks Ronnie. I didn’t know if 97’s like having air pushed through them, some carbs don’t.
I know there is a possibility of running lean, but with a flatty running out of air high up the Rev range, but still having the correct jets to supply the fuel...?
As I said I have an a/f gauge hooked up to monitor running lean.
 
I found the further / higher u get the carbs away from the engine the better for less heat & better performance! The sling shot intake is a great example, gets carb’s away from engine heat plus increases velocity & air intake potential. Lots of different variations available for raised intake setups that accomplish the same.
 
A one piece or original style with hinge ? My old street A ( radical sbc) I raised the rear center support 3/4” and used rubber bumpers on the curve . Just in front of the windshield is a good spot to get cool air . Itll take a bit to make it look smooth but it worked on my A in South Florida.
 
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