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Pressurised airbox on Ebay
Browser - 15/7/07 at 07:10 PM

Not mine, pl enum for turbo car with dump valve fitted.


Benzine - 15/7/07 at 07:35 PM

Anyone know what mods would need to be done to the DCOEs to use this? ^__^


Browser - 15/7/07 at 08:53 PM

AS far as i know carbs have to be designed to take the pressurisation associated with turbocharging. Lotus Used Dellortos on the Esprit Turbo, you can read about it here, specifically this bit:
"This was the first time that these carburettors had been used on the pressurised side of the forced induction system, so they incorporated pressure seals around the spindles to stop the pressurised petrol / air mix from escaping. The Lotus Esprit system remains unusual among turbocharged, carburettor fed engines in blowing rather than sucking, through the carburettors"
So you could suck through the carbs but you are then pressurising a petrol/air mix, not the best idea (I wouldn't have thought) from a safety/cool mixture point of view.


daviep - 15/7/07 at 10:29 PM

The fact that the carbs are inside the airbox means you shouldn't have any problems with the carbs leaking air or fuel as the air pressure is equal on the inside and outside of the carburator. In theory you shouldn't have to modify the carbs at all as this is exactly the same circumstances as a naturally aspirated engine with the carb exposed to atmospheric pressure.

Thats my understanding anyway.

Davie


Fatboy Dave - 15/7/07 at 10:32 PM

Indeed that is correct, but that's called a boost box, which the auction is not for. It's for an air box/plenum that bolts to the side of a set of DCOEs, so you do need turbo spec carbs.

ISTR from the rather dim and forgotten corners of my beer, porn and petrol addled mind that all 'new' DCOEs have spindle seals that allow them to be used with turbos? Could be mistaken though. I hate DCOEs.


daviep - 15/7/07 at 10:35 PM

The link to the lotus diagram differs in that the carbs are not enclosed in the airbox. This means air pressure inside the carb will be greater than the pressure outside and will have the tendancy to blow fuel/air out the butterfly spindles.

EDIT:

Yep I type too slow! Didn't look properly, doesn't even look deep enough to house a set of carbs now that I've had a good look.

You must have to hook up the float bowls to the pressurised side of the system as well I would have thought?

I'm curoius now

Davie

[Edited on 15/7/07 by daviep]


Fatboy Dave - 15/7/07 at 10:37 PM

quote:
Originally posted by daviep
The link to the lotus diagram differs in that the carbs are not enclosed in the airbox. This means air pressure inside the carb will be greater than the pressure outside and will have the tendancy to blow fuel/air out the butterfly spindles.


I know, that's why I posted the above...?