59 replies to this topic

[minilee94]

If we can keep it pretty simple lol would a weber work well with the engine build I'm doing

1275 over bore to 1293
Heplite pistons
Roller tip rocker 1.5
Kent cam either 266 or a 276
Duplex timing chain and gears
Ported and polished 12g940 head with bigger valves
Lcb maniflow manifold with twin dtm exhaust straight through

I know I can either use twin carbs , hiff 44 or a weber but what is a better carb I know a lot of people will say hiff 44 lol the car will be used for driving long distance to work and a weekewnd car also what's the mpg like with a weber 40 also what manifold is best swan neck or straight

[Bungle]

i would stick with a HIF44, you will get good power and MPG

if you go for a webber on a straight manifold you have the cutting the bulkhead IVA hassles and if you go for a swan neck manifold you loose anything you gain with the bends in the manifold

[WiredbyWilson]

You can get a short straight manifold if you choose to, i have a weber 40 on my 1330 and am touching 100bhp, and it has the legs top end in the carb. I was advised that a hif may not have the range of jets to suit my needs.

Mine averages 30 mpg on it which is the same as my 206 GTi daily runner!!

Plus the noise is something you simply cant live without once you have had it. On the IVA issue I have had many MOT guys say they don't see it as a problem.................. make your own conclusion.

[minilee94]

Oh rite okay I was only thinking a weber as they sound nice and as I can get one for a good price

[RossKnight]

Here's a simulated graph of that spec using a hif 44, you'd get better fuel economy with this carb too

[Cooperman]

The 40 & 45 DCOE Webers are fabulous carbs so long as the manifold is a good one. However, to work at their best a high airflow rate is needed, so they are best with a high-lift, high-overlap cam and with anything less than a Kent 286, if you fit a DCOE you'll tend to lose out at the bottom end whilst not gaining at the top end as the engine won't be producing peak power at the mixture inlet velocity at which the Weber is at its optimum. Thus the overall gain will be nil in terms of 'area under the graph' and all that bulkhead cutting and welding, etc, will be for no real improvement.
I built a 1330 GT Clubman rally engine with a 286, 45 DCOE, etc, and it gave 108 bhp at 6300 rpm, but it sure was lumpy below about 3000 rpm. (It didn't 'arf go though).

[minilee94]

So do u think there's no point in getting one then

[Cooperman]

So do u think there's no point in getting one then

If you fit a 286 cam, fit a centre-main bearing cap & fully balance the engine to allow around 6800 rpm and, maybe, fit a closer ratio gearbox with a lower final drive ratio then a Weber would be really good. It would not necessarily be better than a well set up HIF44 or twin 1.5" SU's, but it would work well.
With a 276 cam you would honestly see no real difference from an HIF44 except, perhaps, the Weber would not run so well at low revs.

[Bungle]

Plus the noise is something you simply cant live without once you have had it. On the IVA issue I have had many MOT guys say they don't see it as a problem.................. make your own conclusion.

i dare you to take it to VOSA for a inspection

from the ACE web site, questions to the DVLA

Q) Why does cutting into a monococque affect the vehicle identity if it retains the same shape /profile as before.
A) Cutting is considered to be modifying the vehicle from its original specification. Any modification to the chassis/monocoque body is considered to render the vehicle no longer original specification or of original identity.
Q) Is it acceptable to modify a vehicle bulkhead and/or transmission tunnel when performing an engine change or fitting another make?
A) No, Assuming this is in relation to a monocoque structure. This would be considered a modification to the structure.

[jackmason]

I have a similar engine spec (without the 1:5:1 rockers)

Im waiting for the head to arrive but as soon as its running i will let you know what its like.

This is my new engine spec
-1301cc (1275 +30)
-Kent 276
-Duplex vernier timing gears
-Center main strap
-Megajolt Ignition
-Stage 3 head (35.7mm inlets/ 29.4mm Exhaust) Fully ported and polished
-10:1 Compression ratio
-Weber 40 with 38mm Ram pipes
-K&N Oval Air Filter 83mm
-5in Long Manifold

I had a 1380 before which i had tuned with a HIFF44 and it run perfectly apart from the oil burning problem i couldn't fix but was running 72bhp. That was with a standard head.

[minilee94]

Ahh sod that I don't wuna start pissing around with getting a closer ratio gearbox etc I'm not looking at tryna get mental power out of a weber I just want the sound and a small amount of power is there anything else to my engine spec I can change that would be better for me to fit a weber

[Cooperman]

You do realise that to fit a Weber you will need to cut the bulkhead and that may well give you problems in that you will need an IVA inspection.
I built a 1330 GT engine for a rally car with a 45 DCOE and it really didn't give any more power than my 1310 cc rally engine running twin H4's.

[minilee94]

I was going to run a swan neck manifold and I don't mind if it only give out even like 5bhp fitting a weber

[Cooperman]

The swan-neck is a very poor manifold and if you use one of those you'll probably lose power compwred to a pair of SU's on a gas-flowed alloy manifold.
Why are you so desparate to fit a Weber when the SU's are just so good, easier to fit, easier to insure and, unless on a race engine probably, better all round?

[minilee94]

Because I can get a cheap one and because I love the sound ofa weber lol