Forced induction and carbs?

[ATOYOTA]

just a question with FI i know you can have a PULL THROUGH system with the carb infrount of the turbo/supercharger but whats the deal with BLOW THROUGH do you have to have a presurised box around the carb or can it just 'blow through'?

cheers mitch

[feral4mr2]

dunno if this helps. could be something in this lot that might help?
http://www.google.com.au/search?num=...G=Search&meta=

[Karma Supra]

I *think* its a presurised box!!! The old MG Metro Turbos had a setup like that!!

[ViPeR_NiPPleX]

you can 'blow thru' the turbo, but you will probably find a few issues with that arrangement.

1. If you don't have anything other than solid floats, they will crush under the extra air pressure.
2. The venturi effect doesn't compensate for air pressure, so unless you add an injector or have you car running rich as hell off boost, its gonna lean out and make a mess
3. Making sure the carby will seal alright under boost. The throttle shafts will possibly need to be modified to not leak air.
4. If the fuel pressure doesnt rise above the air pressure, then fuel can be forced back down the lines and you will have empty float bowls in a matter of seconds. You will need a positive pressure sensitive fuel pressure regulator.

Why not go efi?

[skiddz]

hey,

im not sure if it will work for petrol carbs, but i know love KE70 has a lpg blow through carby on a 1g, although he has few issues with running rich it does run quite well drop him a line, im sure he can enlighten you as to what he has, and what does and doesnt work

[joecoolmk2]

carby's aren't designed for positive pressure, that's why most people either have a suck through setup, or they have efi. you can do it, but for the xtra hassle and generally not as gooda results as efi, it's not worth it.

lpg is different to petrol.

[ATOYOTA]

So if i was going to set up a carby turbo id be better running the carb in frount of the turbo?

[joecoolmk2]

yep. what's the car/engine?

i'm not sure if it's a good idea to run intercoolers on carb'd turbos either? all in all, it's not the best way to go about getting power. you might be better off with a supercharger.

[ATOYOTA]

what super charger would i use on a 4k or a 2tg

[joecoolmk2]

get an SC12, off of a 4AGZE, or an SC14, off a 1GGZE. SC14 is a bit bigger, so you can get more boost into a smaller engine. the SC12 was used on 1.6L engines, and the SC14 was used on 2L sixes. holden ppl's use the SC14 on 3.8 V6's too, overdriven of course.

[ATOYOTA]

how much is one of those and how would i mount it

[joecoolmk2]

you can get an SC12 for as low as $300. you'd need to mount it like your alternator, except higher. you'd need to make adaptors for the carb to the S/C, and the S/C to the manifold. actually, you might need a custom manifold.

[joecoolmk2]

here's a 22R with a SC12/14 setup:








hope it helps.

[joecoolmk2]

also, that carby isn't big enough. the bigger the better.

[oldcorollas]

there are carbies designed for pressure. webbers can be converted.
why you would bother when EFI can be done so cheaply i have no idea.

google or ban i say