62 replies to this topic

[minilee94]

Basically I am having mair again about carbs lol

What would be best to use on a fast road 1380 (Please don't start saying a hiff 44 as I don't want one)
The car is used for a weekend ,toy and show car

Engine is a 1380 offset bore
Piper 285 cam
Ultralight flywheel
Orange clutch
x drilled wedged and nitrided crank
Arp bolts all round
Straight through pipe
Fully polished ported head with 30ml exhaust and 36 ml inlet valves ,double valve springs 11 stud
Omega cast pistons 7cc dish
151 rockers
vernier timing gear
Center main strap
And straight cut drops
Oil cooler
Alloy rad
Electric ignition
Facet solid state fuel pump

Edited by minilee94, 09 March 2013 - 08:09 PM.

[minidaves]

webber or bike carbs :)

[minilee94]

I don't really want to piss around with bike carbs lol I just wuna plug tune and play lol I did have a 40 dcoe but is abit too small really

[solihullian]

I don't really want to piss around with bike carbs lol I just wuna plug tune and play lol I did have a 40 dcoe but is abit too small really

a weber 40 isnt too small at all!!......all you will acheive by fitting a weber 45 is no low down power whatsoever and the engine will be overcarbed!

[MIGLIACARS]

twin su s any day

1"1/2 s

look better


webbers dcoe on road cars are a no no for me any way.

if you needed down and out performance the yes a webber.

[minilee94]

Ahh **** iv just sold my 40 to my mate lol just that I got my spec sheet through from bill Richards and they said a 40 is to small as well that I need a 45

[solihullian]

Ahh **** iv just sold my 40 to my mate lol just that I got my spec sheet through from bill Richards and they said a 40 is to small as well that I need a 45

yeah................if the car is used strictly for racing...............which it isnt................a weber 45 is far too big for your spec of engine, get a pair of 1.1/2 su's on it ....like miglia says............the engine will be much more drivable with those than a weber dcoe.......all that webers are good for is doing 10mpg.........

[solihullian]

here we go again.............dilligaf recommends a weber over twin su's.............i hope that you have a big wallet for your fuel bills, its easy to tell people what to do when its not your own money.............

[minilee94]

The car to be honest won't be used loads so the fuel bill won't kill me . And so your rating a 45 or twin 1 1/2s

What about balancing twins some said I can fit a balance tube and they won't un balance is this true

[solihullian]

LMAO difference between me and you, is I've actually had both types on the rollers. Unlike most on here, I don't comment on something I haven't done......if I have to make a educated guess I'll always point that out............

i have also ran (albeit a long time ago when i should have known better) the same engine with twin su's and a dcoe weber on the rollers and to be honest the difference in power with the weber did not out weigh the savings in fuel economy with the su's.
i love the sound of a weber on an A series but with the price of fuel at the moment (and me being a tight git) i wouldn't even think of fitting a weber on any of my engines now............

[solihullian]

The car to be honest won't be used loads so the fuel bill won't kill me . And so your rating a 45 or twin 1 1/2s

What about balancing twins some said I can fit a balance tube and they won't un balance is this true

once the twin su's have been set up then they should stay like it.....especially if the car is only an occasional user, but with all applications a rolling road tune is a must, if you have spent ££££££ on an engine build then why waste possible power by trying to do a d.i.y tune on it at home, that just doesen't make sence.

Edited by solihullian, 09 March 2013 - 08:55 PM.

[KernowCooper]

The weber mith about fuel bills is not true, a badly set up weber will yes use more fuel purely because its over rich as will twin SUs with the wrong needles, an engine doesn't care how its fed fuel as long as the fuel to air ratio is correct be it from a pair of SUs, a weber 40/45 or a Hif44. A given size engine can only burn so much fuel of the correct air to fuel ratio, so if the air to fuel ratio is correct on a weber 45dcoe at 4000rpm and a exact air to fuel to ratio of a Hif 44 the fuel consumption will be the same.

The mith about webers being heavy on fuel is because there are so many webers fitted to cars which are not setup correctly!

And remember my last chat with David Vizard we touched on a 40 dcoe and as only one cylinder at a time is on the intake stroke the car only uses primarely one of the chokes and in a 40 DCOE the biggest choke is 36mm (mods allow a 38mm Choke) so effectively a 40DCOE on 36mm chokes is on par with a 1 1/2" SU.

And I agree with DILLIFAF the spec of the engine above is restricted by a 40DCOE and would benefit from a 45DCOE, a HIF44 is good for 120bhp a weber 40DCOE is not.

Edited by KernowCooper, 09 March 2013 - 09:09 PM.

[minilee94]

Okay and the car will be set up properly on a rolling road

And kenrow cooper so do you think a 45 then

Bill told me running that spec with a hiff 44 will produce 100-115 Bhp will it produce more with a 45

I know it's not all about Bhp but that's all I'm going by ATM

[KernowCooper]

Seeing as you fancy a weber you need to also consider what manifold and to use a 5/6inch DCOE manifold is going to require bulkhead mods, and the weber box as its called nowdays, a short manifold is available from maniflow which they state will fit wit no bulkhead mods, but without running the two on a rolling road to see if the short manifold is a compromise between fitment and power/torque its hard to say, I have a very similar spec to yours and mines on a Hif 44 and performes ok, I just didn't want to cut my bulkhead up and decided to stay with the SU and my center 3 clock instraments.

Is your shell already modded with the weber box or you intend to carry out the modifications while you decide?

And yes I'd fit a 45DCOE with the correct size chokes, you don't want to over choke it as the slow speed air flow will affect the bottom end

Edited by KernowCooper, 09 March 2013 - 10:00 PM.

[minilee94]

Okay thanks and no I have not cut anything and I won't be as I have a custom dash that has Center speedo that I'm keeping so I don't want a box really . I had seen the manifold from maniflow that i want to get wich claims you can fit a air filter and not cut bulkhead and still get good air flow so I might get that one and damn lol 45's are so rare lol