Genuine Walbro WT-990 High-Performance Carb Zenoah/CY Hpi Baja

[carnageUK]

gents

is this carb a straight swop for my exsisting stock carb on my baja 5B ss , is there a noticable difference in preformance with this hop up , are the H & L needle screws the same 1\2 & 1\4 turns from closed .

cheers dave

 

 

[fasi]

hello there,

i had 668wt on my 2wd fg as a stock carb,

then i ordered this wt990 from ddm,

this carb is almost maintenance free but the only thing i have observed is that this carb is very aggressive in terms of throttle response and yes u do need to keep the idle screwed in like almost 85% to keep this carbs thirst for fuel contained...

its worth every penny.

[Carpmart]

In VERY simple terms a motor is a pump and a carb feeds fuel into the pump as it flows the air. The more air/fuel you can get through the pump, the more power you can generate. Effectively the reason a 990 works better than a 668 is that it has less restriction on the flow of air/fuel into the pump. So it's not its ability to deliver the fuel that is the gain, it's the flow overall. A 668 will provide more than enough fuel, just doesn't flow so well due to choke butterfly and diameter .

[flatout!]

Hi guys about these carbs, my km 29cc ported its got a 997 walbro carb on it,? it come with this carb on when i bought the rc baja 5th scale from rc modelz?

is this also a standed carb the 997?, its got a choke on it. And i no the 990 dosent,

[Renllek]

The walbro WT-997 is just a WT-668 i believe.

[flatout!]

Does anyone no the difference?

[patriots-1]

So if the 990 dosnt have a choke how do you start the car?? When choke is needed

[andyknight]

I believe a few slow pulls to prime the engine.

[almighty15]

So if the 990 dosnt have a choke how do you start the car?? When choke is needed

 

Pull the pull start a couple of times slowly, that will generate suction and pull in the fuel.

 

I never use the choke on my KM Baja

[flatout!]

Recipe for a nackered pull start, pulling unnecessarily to start it when it'll start with 2 pulls 1 with the choke and the other it fires, 2 pulls and mine starts every time,

[almighty15]

Recipe for a nackered pull start, pulling unnecessarily to start it when it'll start with 2 pulls 1 with the choke and the other it fires, 2 pulls and mine starts every time,

 

I turn mine over a few times very slowly then it fires up first with the first 'real' pull

Edited March 12, 2015 by almighty15