six throttle injection using solex carbys

[shamus11]

This particular forum doen't seem to get used often so hopefully I get a few replys. I've begun collecting bits to run triple 40mm sloex side draught carbys on my 240z (same as webers).

I love the look and the sound of the side draught carbys but I'd love a car I could go out, turn on and allow to idle and warm up without worying about fouling plugs and rough running and economy. I have some experience with solex carby's as I have another pair on my stanza race car.

I had the idea of making fuel rail and injector setup that fitted inside one of those big long single air filters designed for triple webers. Either mount the injectors in holes drilled in the trumpets or on seperate mounts pointing straight down the trumpets. This would mean the carbys would not be in any way damaged.

Someone we always run our stupid ideas past said they expected it wouldn't run any better on the street at small/part throttle openings as the fuel would be spraying directly onto the backs of the throttles, but that at high revs and racing conditions it could be of some benefit.

What are your thoughts???

[hd240z]

First off I'm no FI expert, but I dont think it would work at idle as the fuel sprayed on the throttle plates would condense to liquid gas and it would have very poor response. The throttle plates are usually colder than the inlet air due to the pressure drop which also makes the condensation issue worse. The control system would be a challenge also. You need a computer with a MAF (air flow) or a MAP (manifold pressure) sensor to determine the engine load and either of those would be difficult to set up with your proposed system. Maybe you could look at a 280z FI head setup and and adapt your carbs operate as throttle bodies?? That would eliminate the condensation issue, but you still have the sensor issues.

Just my thoughs

[hls30.com]

I have a friend modifying bodanker carbs to almost the same situation-just no return conversion.

Will

[e_racer1999]

i know that redline performance makes FI systems that are similar to solex carb set-ups.... might want to give them a try!

[PrOxLaMuS©]

http://www.efihardware.com/efi_throttle.html

[shamus11]

Yes I agree with the problem I'd have at idle. I'll have to have a look at a fuel injection manifold and go from there, the initial idea sprouted from my desire to keep the clean "old school" look of tripple carbs

On the computer side of things I wouldn't use anything but a autronic aftermarked computer as I have a few friends who have a lot of combined experience with these computers, they use MAP sensing

Getting the carbys set up and running them until they become annoying will probably be what happens.

Thanks for the link to the EFI hardware page, I know a guy running these on a SR20, great throttles, bit too dear for me though.

[naviathan]

The MAP setup is easy. Typically what you do is run a balancer tube between the runners and use vacuum line to run that to a vacuum tank. From the tank you can hook up all your accessories and sensors that require vacuum. This topic has been and/or is being discussed on several other forums as well. It's usually best to keep the injector as far away from the valve as possible to give the fuel time to atomize. Welding in or making a bung right behind the throttle mount is common. Top End Performance has a tripple throttle body setup for sale and their prices aren't that bad without the engine management. You could also send them questions regarding their setup and how they over come certain problems. Fabricating and adapting things like this can be a lot of work. Good luck!