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HPMX 40mms, will they work with a turbo blowing though them?

1438 Views 1 Reply 2 Participants Last post by  P_Vilefort
I've got a set of the HPMX 40mm carbs and everything to install on my 2.0 T4 engine build. I've read about pulling them apart to thoroughly clean and set the floats. However I've not read about anyone blowing through them with a turbo.

Anyone with any experiance doing this? What can I expect? Is there a common place that they'll leak? Shou;ld I prep them some special way so they hold pressure?
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I have experience with supercharging Studebaker engines and before you don't think it applies you should know that Studebaker had supercharging from the factory. The best way is to put the carburetor in a pressure box that way the entire carburetor is under pressure. The only place you will have any leakage is where the throttle control goes through the box. You may need to compensate for the pressure by increasing the fuel pressure to the carburetor otherwise the fuel may not be able to get into the fuel bowl on the carburetor.
The only other way to accomplish this and to stick with a carburetor is to seal the throttle and the choke shaft. In the past that was done with lubricated O-rings. Sometimes a set of thin flat washers and small coil springs keep the O-ring pressed into a recess in the body at the throttle shaft location. It may require a shaft that is a bit longer than the original.

The other option and a much better option is to not use the obsolete carburetors and use fuel injection instead. The drivability will be much better with fewer things to mess up. If you seal the throttle body shaft and use a MAF hot wire sensor you will not notice nay difference except it will be much nicer to drive with no flat spots and good fuel economy. The biggest improvement will be the driveability aspect.

I am working on adapting a Ford EEC-IV fuel and ignition system from a 1992 Escort to my '72 Super Beetle. The only thing that I will have to deal with is the firing order; Ford is 1-3-4-2 where the VW is 1-4-3-2. The firing order is built into the Ford EEC but from my reading it I should be able to change that. Why use the Ford computer? Have you priced anything else? Most aftermarket engine controls are in the $1,000 range not including the sensors and they still will need to be programmed. The Ford distributorless ignition is being used on VW engines already so why not use the entire system? The Ford Electronic Engine Control (EEC) computer can cost as little as $86 as a rebuilt by Cardone, the Ford authorized rebuilder. I got one on Rock Auto for $84.90 and it is plug and play. Just need to figure out how to change the firing order so I can take advantage of the Sequential Fuel Injection built into the computer.

Ford actually supplied what was called the Ford SVO Extreme Performance Engine Control System (EPEC) allowing the owner to recalibrate all engine parameters of the EEC computer. It uses a laptop running Windows. The system also has a data acquisition feature to check the effects of the recalibrations. I am trying to find more information about it.
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