Kind of thinking buy a set of CBR 600's, send them to bogg bro's, swallow my pride and say... 'make these work on my 8v!' Only heard good things from their work?

Kind of thinking buy a set of CBR 600's, send them to bogg bro's, swallow my pride and say... 'make these work on my 8v!' Only heard good things from their work?

You need to actually take the car down to them for them to set it up properly. They can't balance the carbs until they have the car running in front of them, they can only approximate the ideal jet size and needle adjustments if you send them the carbs :-)

Well race cars will be using injection in most cases these days surely?

Thats what I thought as well!? So I dunno what people are on about when they say that...

When the carbs are sent to bogg-bro's to be "set-up" , What do they actually change?

Also, do bike carbs use emulsion tubes?

When the carbs are sent to bogg-bro's to be "set-up" , What do they actually change?

Also, do bike carbs use emulsion tubes?

They will only be jetted approximately to suit, and needles approximately adjusted.

I don't know what emulsion tubes are

i'm putting some xjr1300 bike carbs on my 1.4 16v afh and was toying with the idea of webbers but friends i know who have had or has webbers on their car including spen who owns the car in the second picture, have all told me the webbers always re-adjust themselves and have to be re-adjusted every so often, this i think in my opinion is a ball ache, where as bike carbs can be setup and never have to be touched again this i feel is one good reason to use bike carbs.

power all depends on the size of the carbs, how long or short your inlet manifold is and size of the pot. take the r1 carbs for example they have one of the largest pot sizes at 40mm "i think" this been so it can only amount to one thing and that is more air and fuel mixture this equals more power. (right or wrong)

then you take webber 40's or 45's pot size is in the name 40mm / 45mm the 40's will be about the same if not a slight bit better in power where as the 45's will have more power due to the bigger size.

the length of the manifold Determines where your power will be aka (short manifold=low rev power) (long manifold=higher rev power) and (medium you get best of both) this is the one i opted for.

Don't get me wrong, i don't know much about each and i love both but if you wanted something easy to maintain then bike carbs would be the right route, but if its sound and performance you want then i would chose webbers. Its each to their own at the end of the day both are similar in design and the way they work its just up to you what you want and what size you want? a fave is the cbr600 carb. i personally didn't wanna follow everyone so decided to get xjr1300 with a 38mm pot size and when i took them to boggs he said the carbs where very well suited to my engine cc and inlet pots, he said it would give me about 25-30bhp putting that size carb on. whatever you chose I'm sure you will be happy with the outcome. just thought i would answer your question and give a little extra.

Carbs are a compromise.

Injection can be tuned for performance maps and cruise maps, adapt to conditions etc.

Drag cars etc still use carbs and dizzys as they can be tuned for a given state, but little adaptation.

Bike carbs are cheap, although if I was going for it, id rather run twin 40's as you can go to any reputable tuner and have them set properly.

Bike carbs do work, but nobody sets them up anywhere near as good as they could be as it's such a varied application.

Bike carbs are cheaper, I find them pretty forgiving, you have to be miles off to cause engine harm or get undrivable usage

^^ Bike carbs are way more advanced and would be more efficient and perform better when set-up properly. But their development in the form of aftermarket needles etc for cars is in a stage of relative infancy.

The reason they're cheaper second hand is purely market forces (so many bikes being written off compared to the demand for them back into the biking loop, being the main one).

I have never seen turbocharged bike carbs.

I have seen turbocharged twin dellorto DHLA 40Hs in a production car.

Not looked at that many bikes mind.

Define efficiency?

On any fueling set-up , your aiming for an ideal AFR of 14.7 parts air to 1 part fuel (petrol), in lambda terms you want to be between 0.88 to 0.91 (lambda being 1.00)

If your close to this throughout the rev range, you'll be making the most possible power, and getting decent economy as there is very little wasted fuel.

If your getting bad economy from a little 1.4 16v engine on a set of 600's , your not running anywhere near ideal AFR.

So how if your chucking more air and more fuel in to get more piwer will it not use more fuel? I really dont get it.. and it was on an 8v max. Apologies for not knowing everything

Edited 4 April, 201214 yr by erixtar1992

Bike carbs are cheap, although if I was going for it, id rather run twin 40's as you can go to any reputable tuner and have them set properly.

yeah then after a week of driving your car its back in to be setup again, then a week or two after that, then again and again why would you wanna mess around like that? webbers are far more unreliable compared to bike carb's.

I agree with Mikey,

Bits are a bit awkward to get, a good tuner would be able to set bike carbs up right, but would take a lot of messing around, probably lots of needle fetting, emulsion tube changes, main jets, pilot jets, air screws etc etc, after market bits may not be suited to lower revving cars.

My car is pretty bad on fuel, as it runs around 12.8-13.2 AFR at wide open throttle, but cruising, I did 50 miles yesterday and fuel gauge barely moved, they're economical when youre not using their benefits, like a remap.

Mine runs around 14.5-15.5 cruising, maybe richer under inital light accel, but crusing down the motorway at 70-80 tis fine, giving it shit you can watch the gauge go down.

bike carbs are more forgiving in the sense you can just floor it and they almost sort themselves out, twin 40's and such its often better to be progressive on the throttle, think, cars with DBW, you may have 100% throttle input on pedal, but the actual butterfly wouldnt go straight to that.

Depends what you want,

I could set my car up perfectly today, weather could be different tomo and it need adjusting again, carbs are a compromise, more car based engine tuners would be able to set twin 40's up, but bike carbs are a good design, better than SU's and stuff as they're better refined, but just depends what you want.

I have never seen turbocharged bike carbs.

I have seen turbocharged twin dellorto DHLA 40Hs in a production car.

Not looked at that many bikes mind.

I can show you a set of turbocharged bike carbs :nod:

i'm not just saying that because i'm using bike carbs. i love twin webbers and if they where to stay tuned like bike carbs i wouldn't think twice about putting some on my car.

Here you go.....

Its very very simple to do.

I was considering doing this to the AKL in my Polo.

Question I have is whats best for mine - I have a set of Webber 40 DCOEs from my 205 but i dont know if these would be big enough for the 1.6 or if I should sell them and then get a set of Bike or bike bodies?

Define efficiency?

On any fueling set-up , your aiming for an ideal AFR of 14.7 parts air to 1 part fuel (petrol), in lambda terms you want to be between 0.88 to 0.91 (lambda being 1.00)

If your close to this throughout the rev range, you'll be making the most possible power, and getting decent economy as there is very little wasted fuel.

If your getting bad economy from a little 1.4 16v engine on a set of 600's , your not running anywhere near ideal AFR.

Huh? Your first statement makes utterly no sense. AFR of 14.7:1 with gasoline is λ 1!

Stoichiometric lambda value doesn’t change with fuel- i.e λ=1 with 100% ethanol would be at a much lower AFR than say gasoline, the ratio has changed, the lambda value has not.

Also you won’t be making ‘the most possible power’ at lambda one, in fact, run λ=1 at high rpm/load on almost any engine, and you’ll melt something.

14.7 is just where it's burns well for emissions.

On NA cars it's said to run about 12.8-13.2 gives best performance.

Some modern cars run around 16-17:1 for economy.

Some boosted things run sub 10:1 for cooling !

There is no power at 14.7.

14.7 is just the point where all the air/fuel burns, different fuels have different stoich values.

Methanol, 6.4

Ethanol, 9.0

MTBE, 11.7

ETBE, TAME, 12.

Its very very simple to do

Sure, he only had to

"run an aeromotive regulator, add a 6btm set to 1*per pound. His total advance is 30*

He runs 15#s so far on pump. His jetting is 250's He had to change the vent system for the float bowls and boost ref them using little nipples he epoxied into the vent channels. The fuel pressure reg spring was tricky as these carbs only need gravity feed so it was hard to keep from flooding until he got the spring pressure right."

suzuki samurai blow thru with mikuni 38

There is no power at 14.7.

14.7 is just the point where all the air/fuel burns, different fuels have different stoich values.

Methanol, 6.4

Ethanol, 9.0

MTBE, 11.7

ETBE, TAME, 12.

There is power... potentially not the maximum available.

I was considering doing this to the AKL in my Polo.

Question I have is whats best for mine - I have a set of Webber 40 DCOEs from my 205 but i dont know if these would be big enough for the 1.6 or if I should sell them and then get a set of Bike or bike bodies?

Plenty big enough, you change the chokes to match engine size

My Dave Andrews jetting program from 1997 suggests this for 1.6

Weber Carb Settings

• Ideal carb size 40 DCOE
• Choke size 31
• Main jets 125
• Emulsion tubes F11/F9/F16
• Air correctors 170
• Idle jets 45f9 (Weak F8/F11/F2 Rich F6)
• Pump Jets 35/40
• Aux Venturis 4.5

perhaps 40f9 idle for 1600

Edited 5 April, 201214 yr by dvderlm