What's Best Carb Set Up For Pinto

[squashy76]

I am building a 2b with standard 2l injection don't have the inj off car what's best set up got old 32/36 Webber but not sure when building it to use that or twin webbers or bike carbs any advice would be great thanks

[tractor]

i found bike carbs easy to set up and more fuel efficient than webbers

[raeautos]

Bike carbs without doubt.

I have fireblade carbs on my road 2b

And Yamaha thunderace carbs on my track car.

Easy to set up and balance.

[speedtripledan]

They all have there pros and cons. Mainly budget. 32 36 will do the job fine if you are after standardish performance. Bike carbs are good for the cost and give good torque and bhp. Dcoe 40 45.s are my favorite but the most expensive option by far, once set up properly they are awesome carbs. But need a proper expert to get them right.

[Snapperpaul]

You have the best base engine, stronger rods and a better flowing head with the injection spec engine.

The 32/36 if it's not covered in the electronic emissions stuff will work out of the box.

Bike carbs are cheaper and better than DCOE's IMHO but all non standard fuel systems will need setting up

[speedtripledan]

Bike carbs without doubt.

I have fireblade carbs on my road 2b

And Yamaha thunderace carbs on my track car.

Easy to set up and balance.

how's my old gal doing?

[raeautos]

She's doing fine DanE

If I get chance an engine rebuild over winter

Not ailing anything though. Cheers.

[Guest lotusPaul]

Don't consider the "what carbs are better" question, because it's the air flow requirments of the engine that's the factor.

Try this, suck through a drinking straw..the airflow is fast. If you were to drop fluid in its fast moving air stream it would atomise well.

Now suck through a kitchen roll tube, the air moved much slower but is easier to move.

 

Put this thought into the carb question, the smaller venturi of a 32/36 will give good flow up too 'x' rpm because all 4 pots are acting in it.therefore flow through it is much quicker but it will run out soon, hence the 36 kicks into play and the same process is repeated.

The transition between the two venturis is where you may get a flat spot if it's not quite set up properly.but that's only one flat spot to deal with.

To be honest they flow well anyway straight out of the box.

 

Put that context into twin 40/45s off any description and you can see how the initial set up needs to be accurate and couple that with the individual runner ( IR ) of a single cylinder acting on a single venturi and you can see the limitations..it must work across the rev range.

 

This seldom happens well by the time mechanic without experience.

 

Bike carbs are actually more efficient and this can be acknowledged when you see when EFI became the norm and replaced carbs. They were just developed better and for longer. This is what makes them great for our card.

Easy maths, 600cc blade spins to 18k vs 1800cc spins to 6k. Same requirements

 

Back to the question tho.

 

I've said it many times before that the 32/36 is a banging carb straight out the box. Easy and simple and it works well with a bog standard electronic ignition system.

 

I am a fan of webbers but at 45mm I prefere Dellortos because of its transition phases.

 

I have tuned bikes with bike carbs on the motorsport circuits but not much on car four pots, indications are probably cheaper and better than webbers.

 

For a cost option id go 32/36.

For athestics option id go twin 40's

Both will produce good torque.

If you want to be a little different to bike carbs.

 

If you have the money go full fuel injection and get the best of all of them. But a very empty wallet.

 

Paul

[Guest mower man]

Just to throw my 2ps worth in I considered 1 bike carbs 2 DCOE's 3 injection and actually chose a 38 dgas on a 2.1 with a warm cam [ Newman stg 2 ] and a very good head , job after a mild rejet 147bhp ish at crank and 125 bhp on the deck .They all have their supporters mick

[squashy76]

Thanks for info I can get zx9r carbs where would be best to get manifold etc ? What type of fuel pump would be best ?do I need a pressure regulator ? and what sort of pressure does it run at ? Thanks again for the help

[maccavvy]

Danst engineering for manifolds

Best fuel pump is the original mechanical one

You will need a regulator..search for sytek on ebay

2 to 2.5 psi usually works fine

The rolling road place will set it up though

[knights_templar]

indulge me

 

can anyone give me a reference, web site, technical paper, doctor, professor, or non follower of fashion, that shows that a bike carb, designed for a one litre engine can give the correct fuel air ratio over the entire rev range of a two Litre engine, without considerable modification from standard.

 

tin hat on, prepare for incoming.

 

basically give me provable, repeatable evidence that bike carbs work anything better than a fuel tap?

 

challenge on........................do you accept?

[fry61]

Hi Simon, from my very limited understanding of fuelling -- were they not putting forward the belief that 1000rpm x 2000cc car = 2000rpm X 1000cc bike

 

Me?? I'm sticking to injection just as Mr Ford made it!!

[knights_templar]

I would go FI too

 

it is nothing to do with RPM.

 

one cylinder of a two litre engine, is 250 cc per cylinder.

 

air flow dynamics accepted. each cylinder would draw in approx 250cc of air at each induction stroke, the carb must mix this air with fuel so that is meets the correct fuel air ratio.

 

a bike carb, designed for a 1 litre engine, will expect 125cc of air for each induction stroke.

 

correct fuel air ratio?

[MarkBzero]

A set of twin dellortos for me every time, the sound and performance is great.

PS. I don't care about fuel economy it's only for fun!