45's should be adequate unless your planing a serious head/engine spec. scottmk1 is correct about the 1600 engine he mentioned. it will need 48 carbs to run it 'properly', peak power will probably be in the top end 6k - 7k range with a 320+ degree cam. it's a race engine so wont run much like road engine would.
no probs m8 turned into a nice thread pol8,there is a possibility ill need 48's but im gonna give the 45's a chance as i know theyre good is it just the ford lads that seem to run bigger carbs than everyone else? pretty much all on 48's and 50's!
Pol8, as far as I know even the F3 1.8 8-valves putting out 210-220bhp+ only ran 45mm Webers. You'd have to have a pretty serious 1600 to need anything bigger than that.
have a little look at this thread on PVW Click here please... notice i've listed a spec for a 1600 X-flow ford lump running a 292 degree cam, 11.5:1 compression ratio and 40s.... Now are you really sure this engine you have is going to need 48s?
Prof- if i bought it, it would be to use in a track only car. But, before i buy it theres a few things i need to know from the seller, regarding whats been posted here.
ahhh that's different, but they are still big, i'm sure a set of 40s would do the job and be more drivable, what ignition is it using?
The bottom end has been built up, so has the head as far as im aware, but then engine hasnt been built up and used so there is no ignition on it yet, and tbh im not sure what ignition would be needed to run it. I asked about using the 40's ive already got on my current 1600 on it, but the guy said its been built and flowed to run 48's. Im not sure about some parts of it though, the pistons its running are flat topped, and the head has been chambered? where the standard 1600 uses dished pistons and a flat head. Any benefits from changing to this setup or any reasons for doing it?
Have you tried looking in the back of classic ford magazine or similar? There always seems to be 48s for sale in the back of there, very popular with the MK1/MK2 escort owners. Also manifolds for the 48s are always advertised separately compared to manifolds for 40s and 45s, so that may mean there are slight differences, but thats me having a guess.
i thought that 45/48 mount the same to the manifold but i'm not sure on this one.... i am sure that a 1600 doesn't need 48's. If an engine builder says to you "it needs 36mm chokes" or "41mm chokes" then he's put some thought into it if he tells you it needs 40's, 45's or 48's then he's just pulling a figure from thin air...
so if it's running a really high compression and big carbs it'll be very likely to pink so a mapped ignition will be a benefit, so then you might as well run full ecu on it and use the 40s with blocked jets and injectors
lol, keep going if you wish, but all i can reply with is that i dont know lol. Oh, ive got How to build and power tune Webber and Dellorto DCOE&DHLA carburetors too
it must be using a later eng if its got a chamberd head?agreed 48`s are way to big for a 1.6 and they point in the wrong direction
one of the better sources of info - it summed up about half a dozen other books i wasted time with and explained it all so a thickie like more could get my head round it...
