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bike carbs onto 1800 cvh. Help please
steve8274 - 1/3/10 at 10:26 PM

hi
i have a standard 1800cvh engine with existing wiring and ecu which i am using and i wish to swap from my standard carb to motorbike carbs. my questions are
what are all the components i need?
can i continue using existing wiring loom(it isnt edis)? standard dizzy cap and coil
how difficult is it to set up once installed?
any help appreciated
thanks
steve


Steve G - 1/3/10 at 10:34 PM

Yes you can - your ignition system is totally independant of your fueling system.

You'll need carbs (strangely), manifold (Bogg Bros or make one) air filer and blank backing plate, ideally a bike fuel pump at the back of the car below the tank.


AdrianH - 2/3/10 at 07:41 AM

The carb Sierra 1.8 CVH has the esc-hybrid system.
The module takes has a MAP sensor built in so you would have to have a common pipe going to that from I guess some sort of reservoir. It also has inputs from air temp and engine temp sensors to determine the spark position.
It drives a heater in the choke circuit to enrich when cold, but I guess that could be bypassed or just not used and have a manual choke.

So I would guess if you could still incorporate the sensors it may well work.

What I do not understand is, if you get more fuel/air in the cylinder with then do you need to advance the spark or not. The esc hybrid will be set up for the standard carb.


Adrian

[Edited on 2-3-10 by AdrianH]


ashg - 2/3/10 at 08:23 AM

in my opinion bike carbs without megajolt is like a car without brakes.







Pretty Pointless.


whitestu - 2/3/10 at 08:56 AM

quote:

in my opinion bike carbs without megajolt is like a car without brakes



For years people have been fitting twin webbers to cars to get more power, before megajolts and the like were available, so no reason why you won't get major beneits from fitting bike carbs with standard ignition.

Stu


steve8274 - 2/3/10 at 12:23 PM

hi
i will use something like megajolt eventually but just wanted something to start me off. (cashflow) if i leave the carb on as it is, i have to cut bonnet for space. i want bike carbs eventually so just thought go with that straight from start to avoid un necessary hole in bonnet.
if i changed my system to edis system, would that make it easier with all connections etc.
thanks


AdrianH - 3/3/10 at 12:28 AM

Hi Steve; sorry if teaching you to suck eggs here!

If you change over to EDIS you will have to add an external ECU such as Megajolt or Emerald or something else. I am running a 1.8CVH with the standard carb and have thought about bike carbs, but for now I am happy with the hole in the bonnet. I think it can be done with the esc-hybrid as I mentioned you need to add sensors to the bike carb set-up, but you would also need to to similar to Megajolt.

If my memory is correct you can use either a throttle position sensor (TPS) or manifold absolute pressure sensor (MAP) for the Megajolt. TPS is generally easier but MAP just needs a vacuum pipe from each carb into to a small can and then a small vacuum pipe to the sensor. The small can evens out, or gives an average pressure/vacuum to the MAP sensor.

The wiring from the esc-hybrid will not be any more complicated then for edis and megajolt and I would imagine not difficult to go between the two. Ignoring the choke the sensors on the standard carb provide incoming air temperature, engine temp and MAP, if you go bike carbs you could stick the air temp sensor on a mounting plate you use to mount the air filter. You would have to add the engine temp into the water system as you would loose that from the standard inlet manifold.

Other jobs you would need to sort would be the thermostat housing and lastly the temp switch for the radiator fan, all these are normally on the inlet manifold, but all doable else where. You would still have to solve the same issues with Megajolt.

You have to get the bike carbs set up and you would have to get the megajolt set up, generally done with use of a rolling road and a good specialist.

Ash has fitted bike carbs to a 1600 Pinto and also used Megajolt and his experience is in this months CKC magazine, well worth a read.

Cheers

Adrian

[Edited on 3-3-10 by AdrianH]