converting 1200i nova to Carb? Help?

[johnny27]

Hi guys, I'm going to convert my 1200 single point injection nova to a sr 2E3 Twin choke carb. I've changed the jets to suit the smaller engine but will there be any problems fitting the carb? Will all the pipes match up alright? Will i need to change me ECU? I really need help on this, much appericated, by the way i've got the proper inlet manifold. Thanks.

[peester]

i can't help much but i do know that all electric bits need to be switched to mechanical. think you need manifold and carb and theres not much gain in it really. a 1.4 spi carb/system should fit and give a gain not sure. someone else will help mate.

[johnny27]

I will definetly need to switch to the 2E3 carb as I will be running a 1300 head with kent cam, so this means bigger valves and longer duration so the twinchoke carb will feed more fuel to it. My carb i am going to put on is automatic choke so that is'nt a problem, anyone else ever tried this conversion? Anything else need changed? Thanks mate

[johnny27]

Also, i've rejetted slightly bigger than 1300 to make use of my K&N filter so it actually makes a difference to the mixture

[Aragorn]

you'll need to junk the entire ignition system and fit a standard system from an SR

also if its a k plate it will fail the MOT cos u cant run a cat with a carbed engine

[johnny27]

If I change my exhaust system to a sr with no cat should I be able to pass MOT, considering i have converted the car over to carb? Also would I need to declare this modification to DVLA? Thanks for your help guys

[mark_GSi]

if your car is registered after Aug 1992 then u need a cat by law

1 exception:

if you have a engine conversion and you can prove the year of your engine (pre cat) then you are allowed by law to no have 1

[Snowface]

ur prolly better off getting a 1.2 or even a 1.3sr for under a ?100 and doing it on that. A lot more simple and u can use ur 1.2i for spares or sell it maybe.

[johnny27]

Few problems here lads, switching to carbs is my only option, you see I won't be able to get a SR or 1.2 carb engine here in Northern Ireland only really GTEs. And I know there is no way to tune up the SPI, this may sound silly but is there anyway of using a GTE multi point injection system and gte ECU? As I can easily get the full system, thanks for your help.

[Snowface]

Few problems here lads, switching to carbs is my only option, you see I won't be able to get a SR or 1.2 carb engine here in Northern Ireland only really GTEs. And I know there is no way to tune up the SPI, this may sound silly but is there anyway of using a GTE multi point injection system and gte ECU? As I can easily get the full system, thanks for your help.


lol. there are always options, and i've heard u can do this but i think u need a diff head with bigger valves that the GTE has.

[mowgli]

the 1.3 engine was fitted in tons of astras and cavaliers get to a scrappy and buy what you need.. the 1.3 sr engine was not a special in any way, it was simply an astra lump with a low diff in the gearbox.

[Snowface]

the code for the engine you'll find stamped near the Oil Filter is 13S.

[geordie_racer]

just get yourself the head/carb/inlet manifold off of a 1.3 mk2 astra cost you ?30 on a bad day.

as for fitting. the autochoke needs connecting to a switched live (black wire). you need to lift up your back seat and remove the wire goin into the fuel pump and tape the end off. you need to remove the 2 fuel pipes from the spi and run the fuel pipe to the mechanical pump on the new head, then run a small section of pipe from the other side of the pump to carb. as for the other pipe i just connected it to the 1st fuel pipe with a t piece. as for the rest of the injection wiring it just needs taping off tidily and put out of the way. the other thing to note is on the astra head there will probably be a bit of wire from the dizzy to the coil take this and connect it to your current coil.

think thats all that needs doing from what i can remember then u just need to get non cat exhaust system a gte system will be fine. 1 quick thing why did you change the chokes in the carb it realy wouldnt have made a difference and if anything i would think slightly restrict performance.


and as for the comment regarding the cat and mot, NO nova ever needs a cat if you care to take the time to check a ministry of transport list for vehicles that require a cat you will not find a nova on the list

hope this helps anymore questions ask
chris

[johnny27]

Hi Chris, thanks for the great advice, question about the jets you asked, I changed them because the carb acutally cam off an mk2 astra 1600, so i think using the 1600 jets would flood my little measly 1200 engine. Again you've been a big help as i did'nt know about the pipes on the new carbs, cheers