Does anyone know anything about cowl induction?

"BiTurbo228 - Dr Frankenstein of Spitfires" (biturbo228)
03/13/2015 at 18:24 • Filed to: Spit6

I'm planning to have a crack at making one on my Spit6 project by extending the bonnet bulge over the top of the heater inlet and then ducting it to the throttle bodies.

Couple of benefits:

1. Cool air and a bit of a ram air effect

2. Saves space at the crowded front end for oil cooler and radiator, while also avoiding heat soak from them

3. As far as I can tell, no-one's ever done it on a Spitfire/GT6 before :)

Question is, how close to the windscreen is optimal? I really have no idea...

DISCUSSION (8)

itschrome > BiTurbo228 - Dr Frankenstein of Spitfires
03/13/2015 at 18:36

from what I understand the principal is that a low pressure zone should form under the cowl and the base of the windshield. this low pressure zone creates a bit of a vacuum to pull in air into the intake. this proves a bit of a higher pressure (see ram air like effect) and should provide cool air with a lightly higher bar than a normal intake.. but it's all GM bullshit if you ask me.

edit: oh i re read. yeah no idea how to determine the max effective distance need. can you build a model and wind test it? or generate a computer model and run it in some kind of software. No idea how to figure this out with out maths and models.

AthomSfere > BiTurbo228 - Dr Frankenstein of Spitfires
03/13/2015 at 18:36

I think it would be good to define optimal.

What yields the best performance might also mean that it increases the odds of getting water in the wrong places...

I am also no expert here, but is optimal max performance or a slight tweak to your setup without creating any risks.

Arch Duke Maxyenko, Shit Talk Extraordinaire > BiTurbo228 - Dr Frankenstein of Spitfires
03/13/2015 at 18:38

Here you go:

http://www.hotrod.com/how-to/engine/…

BiTurbo228 - Dr Frankenstein of Spitfires > AthomSfere
03/13/2015 at 18:41

Good question...

I've read about water ingress problems, but I think I should have that covered by positioning the intake over the top of the heater inlet. That's already got drainage channels in place to stop that, so any rainwater should be caught by that and not pulled into the engine. That's what I'm thinking anyway :)

BiTurbo228 - Dr Frankenstein of Spitfires > itschrome
03/13/2015 at 18:43

I don't know, there seems to be a bit of sense to it. Take air from a place where it's at a higher pressure (base of windscreen) so you get higher flow. Whether it's noticeably higher pressure than an intake positioned at the front of the car I'm not sure. I'd love to see some scientific tests done on it, but it's tricky because the results are only visible at speed (or if you put a socking great fan in front of your dyno).

Would be interesting to see what performs best...

itschrome > BiTurbo228 - Dr Frankenstein of Spitfires
03/13/2015 at 18:46

yeah I agree. I would love to see some true science on this.

RustedSprinter > BiTurbo228 - Dr Frankenstein of Spitfires
03/13/2015 at 18:53

cowl a bunga dude.

BiTurbo228 - Dr Frankenstein of Spitfires > Arch Duke Maxyenko, Shit Talk Extraordinaire
03/13/2015 at 18:58

Perfect :) thankyou