kinds of Carbs for forced induction?
Turbo Mini Forums

What kind of carbs are people running?

specifically m45 supercharger, I see a lot of people using single SU carbs.

I thought when increasing more air, you would have to uprate your carb too, like a weber 40.

is my logic wrong? is there any power benefit to fitting a larger carb?
Jeff

On a turbo's mini is has been proven that a single 1.75" SU can flow enough air for well over 250bhp.

I don't forsee the 1.75" carb being an issue for the M45 which will never be able to reach these power levels.

If something is worth doing, it's worth doing half of.

You put it well John.

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

If you run a suck through system then a single 1 3/4 is more than capable. If you run a blow through then a turbo carb is fine.

I have the second.

WWW.TURBO-MINI.COM

Jonny sti used a 45 on a suck through now has a blowthrough using a hiff44 and has more power!! If it were me i would use a 44 and change the long neck thing they use on suck through sc setups for aomething shorted as i have heard they can be a tad anoying on start up

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

Searching is all you need on TurboMinis

I know that silly, but it has the breathers in different places

the n/a and turbo HIF44's can be used for either, most of the turbo stuff you block up anyway

Edited by Brett on 8th Nov, 2010.

Yes i moved to the darkside

Instagram @jdm_brett

Suck through is where carb sizing needs to match power output in terms of airflow.


When blow through, just ram boost down its neck and it'll work lol

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

then why do I see this?



Eaton m45 w/Weber? what is the purpose? maybe 1380?

On 8th Nov, 2010 jeffreypang911 said:
then why do I see this?



Eaton m45 w/Weber? what is the purpose? maybe 1380?

Edited by EricsAmerica on 9th Nov, 2010.

Eric
my pics.... http://www.fototime.com/inv/7AAF37CF3EFA956

On 8th Nov, 2010 jeffreypang911 said:
then why do I see this?



Eaton m45 w/Weber? what is the purpose? maybe 1380?

Yes i moved to the darkside

Instagram @jdm_brett

i suppose it is hard to wrap my head around how the SU carb could provide enough fuel if more air is mashed into the engine.

I was to run a weber setup because of this logic. that more air would need a better fuel delivery system for more fuel to get a better mixture.

Also following this equation that a single hif44 would be enough, why do people fit dual, and find the performance better? is it just different with forced induction, or even maybe supercharger specific?

Edited by jeffreypang911 on 9th Nov, 2010.

Dual carb setups were designed to run when smaller carbs were the norm. This did help the flow issues somewhat with more direct intake systems with a carb facing directly at each intake port. Now with the hif44, more than enough air and fuel can flow with it along with better designs on the intake manifold and head. When you think about it, only one cylinder draws fuel/air at a time, so as long as the intake/head flow is at it's best, a hif44 should take care of the highest flow demands physically possible.

As for the weber, it is a very cool carb that was designed to be adjustable for just about any car on the road in the correct layout from the a series to a v12. I like them so much, I use 2...

Eric
my pics.... http://www.fototime.com/inv/7AAF37CF3EFA956

There are plenty of us running blow through supercharger set ups with HIF44 carbs. So far I've not met a supercharger runner, suck or blow through, that has had a problem running that carb.

But as said above it's totally down to you, there isn't really a wrong or right set up so find what works for you. I'll be sticking with my turbo carb.

The HIF44, has been proven to fuel for 250+bhp, and there is around 10 people now with the magic 200, all on HIF44s...

Yes i moved to the darkside

Instagram @jdm_brett

I'm a bike carb fan... just to get rid of the dash pot oil

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Carbs... Pah!

Why do you see any mod that different, we all do different stuff, nothing is 100% correct as so much stuff works you can't say it's the "only" way of doing it :)

On 8th Nov, 2010 jeffreypang911 said:
then why do I see this?



Eaton m45 w/Weber? what is the purpose? maybe 1380?

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

one of my mates (Big troy) runs a Mk2 escort with turbo,,, he`s got 360hp & running through a 36mm restricter

soooo , the way i see it,,, a single 1&1/2" SU should be good for that also---ish

Edited by MadMatt on 10th Nov, 2010.

www.miniman.com.au

"""LazyGoodForNothingSmartArseKnowItAllBackYardMiniMechanic"""

mikuni hsr:s are good for suck through, 42/45/48 mm flatslides

internationally known as "big" swede

The only advantage I can see to using a webber and an M45 are to the profit margins of BP!!

But seriously, what power are you aiming at? As said above the HIF44 is suitable for big power blow through, but would you use a HIF44 on a 130bhp NA engine?

If not then look elsewhere for a suckthrough carb.

I would bear in mind that when using a supercharger, your engine is really making more power then it shows as you loose a signigicant amount driving the thing.

So maybe do your calculations on carb requirement on 150bhp for a 130bhp output.

Edited by wil_h on 10th Nov, 2010.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

I think I will end up going for the SU carb instead. I would think an HS6 would be more than enough, but would I want to use a HS4 instead?

Id like 130-140hp.