Need help with Weber Twin 40's

[supernova86]

Hello everybody, I am looking at fitting a set of weber twin 40 dcoe's to my Nova 1.4sr, what exactly do I need to get them to run right? I was reading your how to guides and it suggested fittin a new cam, I looked at fitting a Kent sports cam kit would that be adequate for the job? Or do i even have to bother changing the cam? Also the fuel pump on your guide it said with the T40's it was ok to use standard fuel pump, would it be better to upgrade it? Is there anything else i need to consider when purchasing them? sorry to ask 20 questions just really unsure and would like some proffesional feed back. If you could email me back asap i would really appreciate it...

Many regards Tom

[Rexy]

For a start you'll need the carbs make sure there matched, Linkages, inlet and alt bracket. http://www.tuning.co.uk/vauxshop/

For the fueling, run the Mech pump that should work fine but people usually run a regulator to get the pressure down IIRc 3-4psi is more than enough for the webers.

then you've got to look at your engine setup and relate this to what jet and choke sizes you run.

Read up on the sport spec that will give you an idea, Blystien B+ head with kent ast2 cam + webers = :D

[Mike]

yes, a fuel pressure regulator would be a good idea to lower the psi to an adequate level, although this isn't necassary (i think?)

a matched cam would go down a treat with a set of 40's. and a decently profiled head. event fast road as this would be better than standard and cheaper thana B+

If you keep your eyes open on ebay and used rally car parts sites/shops/add's, you can get a decent head and carbs and all the necesarry bits.

all my 40's + carb setup came of ebay along with a B+ head for ?100

mike

[leemh1234]

them b+ heads are crap yeah go for a cam aswell and a good gas flowed head and get the carbs set up on the roolers and u'll ave good power and if u can get hold of 1 get the old b reg 1.3sr gear box or a gsi unit for good measure 8)

[tinyrally1]

How can you say a Blydenstein b+ head is Cr~p. He's been doing cylinder heads for longer than we've been alive and as far as i know, they're one of the best around

[Mike]

B+ heads are carp are they? :|

What planet are you on matey? Its the ulimate 8 valave cyclinder (for a Nova that is)

:roll:

[Stuart]

not quite the ultimate, but deffo the most well known in our circles ;) and big respect to him.


the mech pump is fine if your keeping the revs below 7-8K, after that it will probably start skipping hence why im going to run an electric pump and reg on my 1.2 Vs Jim whos running the mech pump and reg on his "big" power 1.6...

to be fair if your going to all the hassle of changing to webers then id suggest getting a 1.2/1.3 head and suitable manifold OR a 1.4mpi (sri) head with a 1.6 inlet.... these will offer improved head flow without too much cost, the 1.4mpi ehad being the "best" option as benji did this and gained just over 10bhp.

a lairyer cam is purely an option, but whlile your doing all this messing about you may aswell fit one if you can get one cheap eough etc... Kent AST2 being the "minimum" you want and the Piper BP300 being the better choice (or go to cat cams and get something a bit better for a little more money)

[tinyrally1]

I reckon a company called Nelson are the ultimate for the 8 valver

Ive just built a motor with a B+ head and a Kent AST2 cam and its perfectly driveable at low revs, but when you reach 3500rpm, it just takes off. Played with engines with lumpy cams can take a bit of getting used to. At the moment I keep stalling cos i dont give it enough gas to pull away

[Dan]

lmfao, i'll add the b+ head to the alleged other mistakes i have made to my car then :lol: :lol: :lol: :lol: (some will get that gag)

Tuning for the max isnt always what its about. my engine could be taken alot further than what it is, but then its done over 40k, its reliable and returns decent mpg, enjoys trackdays and is reasonably nippy. Plus the fact it pulls well from low down if i'm being lazy and cant be bothered to change out of 5th gear whilst doing 16mph+. But then in the beginning i built mine originally as an allround car and this is what the engine was based on to satisfy what i wanted.

The rest as they say is history