mstalli

I was wondering what, if any, will be the difference by replacing my Walbro 668 carb with the Walbro 813 Carb. The carb will be mounted using the Billet Delrin TGN manifold to a 27cc CY motor. Thanks for the input,

Jason

hellya

the 813 carb has a built in accelerator pump to help with any low end lag. This carb has a 15.88mm bore and a 12.7mm venturi

the 688 carb has a 15.88mm bore, 12.7mm venturi also but no pump


813 will help with any low end throttle lag... also a new 8000 cluch spring will also help

mstalli

Thanks for the clearification. I think I may get it just to have it. I did install the 8K spring on the clutch and what a difference. It hits hard and is awsome. I had to order new gears already being that they are on the verge of stripping. Going to the aluminum gear and stepping down 1 tooth size. Should be interesting. Now I just have to get a pipe!!! Any suggestions?

clubin

What is it you want to put a pipe on? Or did I miss somthing.

hayabusagreg

Get the 771 Walbro in the boat section on the O`neill site don`t get the 813 if you running a small cc none ported mill. Call them and find out why. [)]

mstalli

I have ported the mill. Should I now get the 813?

mstalli

I have a Hobbypro ford GT with the 23cc CY motor which I have increased to the 27 cc top end. I have also ported the s*** out of it. I've also changed all the suspension to aluminum from FG and tires from PMT. Ive also changed the manifold, the clutch spring and the rx and tx. I'm looking for a good deal on a pipe that fits and the body will fi as wells and I don't want to spend 350 bucks on a pipe. Thanks for the help if you have any!1 Jason

mstalli

I want to get a pipe for my hobbypro but I don't know what to get. I have the CY 23cc top end and a CY 27 cc top end that is currently on the car. Everything on the car has been updated with FG aluminum and I have done mods to the engine. I guess my last step is the pipe and Im wondering what to get. It is the onroad Ford GT. The only thing that is original is the chassi, the servo holde, gas tank and pipe. lol I also have the TGN "HP" manifold. I do notice a big difference on the low end side when I have that manifold on but I cant get it to run smooth on the top end. Any ideas.

splcrazy

is there any sort of homemade mod you can do to the stock carb thats in the baja 5b ?

splcrazy

today i got one of my old stock baja5b carbs and modified it myself , took out the choke , filled the holes , and then raceported it . i havnt tried it out yet but i will next weekend when i build my TS engine , DDM want $49 and its been on backorder for years lol i think they forgotten about it .

here is pics of how mine turned out i took two pics before filling up the holes from the choke removal

clubin

How are you going to start the engine with the choke gone?

splcrazy

lol the 813 is a chokeless carb , my carb is a 668 with choke removed raceported and the holes from choke removal filled with epoxy , they also sell what i just done to my carb as a mod on DDM for $49 .

to start choke less carbs , you prime the bulb press the trigger on transmitter to open carb flap a couple times then pull the starter & it fires up. the benefits of chokeless carbs is that you dont have a second pin with flap in the way from the choke , helps with clean smooth air flow from the start of the carb intake

bsrman14

The 813 carb is used for boats. You put your finger in the carb to choke it.

savagecommander

i'd be careful modding the carb throat- thats a really touchy area to grind on....

mooman007uk

The 813 has an accelerator pump so when you pull the throttle it squirts gas into the intake, same as holley double pumper does, the 668 doesn't have a pump so pulling the throttle a couple of times doesn't squirt gas, it might be tricky to start with no choke or pump...maybe pull a couple of times WOT to get gas in the cylinder then again with the throttle closed.

cyclops1970

My Feedback: (5)

i have only ever used no choked carbs .. no big deal .. you just use your hand instead of the choke flap .. i have had 488 race ported carbs 813's no choked

Boosted Weedwacker

I have littel project going on i'm building a centrifugal supercharger for my 32cc mcculloch engine but I know I'm going to need a better carb for more fuel I currentley have a walbro wt434,wa229 and a zama m29d im looking for a carb with a built in pump and no choke sometnig like a walbro wa229 but better.

bsrman14

Mcculloch engines are junk. All RPM no power. Homelite engines are good. Echos are ever more better than a mcculloch.

Boosted Weedwacker

the problem is the Mcculloch engines had too much back pressure they have a 1/4'' hole on the muffler thats why they have no power but in my case i think Mcculloch engines have plenty of power when you bore a bigger hole in the muffler you also have better throttel response .but I do agree whith the Echo engines there nice engines but unfortunley all i have is a Mcculloch engine.

Nitro Fumes

With cars we have this big air filter on top so you can't choke it with your finger.