the other way to make a weber work off road

[brad-chevlux]

I spent the day thinking how you were doing this!!
How is it coming along the theory behind it it should work good.
Takes a bit to get the head around the hows and whys but it should provide enough fuel to supply the motor but keep it low so not to flood.
Nik

the basics behind it are old school. it was first used for off road racing buggies. They used it to stop stop fuel slosh effecting the carb.
that bit is easy, metered inlet, scavenge anywere in bowl at fuell hight and fuelcell foam to stop the slosh.

The trick is makeing it work on big angles. the pick up point for scavenge has to be in the right spot. other wise it ends up no better then the float, needle and seat arangment.
The first hill i drive was a bit of a let down. back it up was fine. go up forward = instant flood
slight change to pickup. = reverse of the above

then next change = can almost stand the thing on its tailgate

tell you what though. on the first full day wheel, i'll be taking a modified float and needle and seat just incase some thing fails.

[NIK]

Very interesting makes me wonder why no one else has done it?
Nik

[GRPABT1]

Cough *injection FTW* cough lol. Seriously though this seems really smart but simple, well done Brad, love to see it in action when Scott gets back.

[NIK]

Was just thinking about this thread!
So by running unrestricted fuel in and a scavange pump there will always be fuel to feed the motor but never enough to flood the carb??
Sounds like a bit of messing around to get it just right but should be worth it.
Nik

[want33s]

Was just thinking about this thread!
So by running unrestricted fuel in and a scavange pump there will always be fuel to feed the motor but never enough to flood the carb??
Sounds like a bit of messing around to get it just right but should be worth it.
Nik

Yep its just a dry sump setup turned upside down.
The more scavenge pipes fitted the better it will work but you'll need a multi chamber pump... One chamber for each scavenge pipe.
Jas.

[brad-chevlux]

Was just thinking about this thread!
So by running unrestricted fuel in and a scavange pump there will always be fuel to feed the motor but never enough to flood the carb??
Sounds like a bit of messing around to get it just right but should be worth it.
Nik

Yep its just a dry sump setup turned upside down.
The more scavenge pipes fitted the better it will work but you'll need a multi chamber pump... One chamber for each scavenge pipe.
Jas.

Yeah tell me about 'a bit of messing around'.
though being the first one, it was always going to be a big job to get it right. To do it again would be alot easier.

we took it for a drive last weekend, (scotts back now) and we found out the on side angles the ute will fall over befor it will suffer fuel problems.
we didn't mean to put it on such a big side angle, but it did prove the point for us.

we only had about 15L in the tank. and on one of the up hills the pick up in the tank went dry, still no fueling issues.
though a few weeks back it did have it on a far steeper up hill.

Down hill is the same, you be worried about how steep it was and probably not want to drive down it anyway.


All in all, i'm very very happy with the out come. if i was to do it again there are some things i'd do slightly differntly.
I beleive though that the one stand pipe is enough. provided it's inthe right place. the limiting factor would horsepower. because you need to provide enough fuel for peak power, with just enough extra to still return a small amount of fuel. The return fuel is what keeps the scavenge pump cool.
In this setup, i've provided enough fuel to suport about 160hp, roughly twice what eh engine realy needs. It's all to keep the scavenge pump cool. any more then that and you probably need a second standpipe and scavenge pump.



If anyone els wanted one it done, i could rebuild and modify the carb for $320 and give you a list of parts and the layout to use.
be warned though, with the carter elec pump being about $100, the extra hoses clamps and wiring, it's not cheap job, however it does work very well.



Josh, well have to organise a trip one weekend, i can ride shotgun in scotts ute untill my patrol is sorted. On that note, want to learn how to rebuild swivel hubs? i'll show you if you help me do mine...................

[GRPABT1]

Sounds good mate

[Adsport]

any chance of getting an image of the setup inside the bowl ?

is the scavenge pump running off alternator triggered/generated power (running only when engine is turning over) or is it switched to be active whenever the ignition circuit is on ?

do you think that the scavenging pump could pull enough vacum to affect the venturi ?

thanks for sharing what you have thus far , nice work.