I just installed a 440 kit with mild port work stage 2 hot cam sparks x6 pipe FCR39 carb. Now I am having a hard time getting it to start. Once it does start it runs great and fires right up. Let it cool 1hr very hard to start and backfires thru muffler. I checked: woodruff key OK, valves set at 6 in 8 ex OK, cam 2 lines level with head 1 straight up OK. Any help would be appreciated.

 

From what i have heard from other people with big bore kits, hard starting is normal when cold. Do you choke it when starting?

 

Try jumping up to at least a 42 on your pilot jet. Mine starts great now, hopefully it will still start good after i get a 416 kit.

 

i would also raise the pilot jet. also, with the hotcam, you remove the decompression assembly which helps for starting. i noticed mine needed a pretty good battery for it to start as easy. i see that you have an fcr already. i don't know much about that carb for tuning, so maybe others can help you there.

 

really sounds like a pilot that is to lean. have heard that some black boxs cause this.

 

I am running a FCR 39 with a 52 pilot and a 170 main, to start with - I also have a WB black box. This carb has no choke. I tried hitting the thottle a couple times then try to start. I am thinking the pilot jet may be too rich and flooding the motor. ANY thoughts are welcome.

 

the choke helps a lot with starting when it's cold. i have a stock bore 400EX and starting it cold is a pain in the butt, with big bores that jus makes it harder.

 

oh ya, i forgot, my chocke lever is broken so i have the chocke zip-tied open, that's y it's hard to start. lol, i forgot to put the whole reason i said what i did. lol, sry bout that.

 

I would go with too rich also. I would call FCR tech department..they can probably get you dialed right in.

 

Thanks everyone for the help so far. I called SUDCO the dist. for the FCR 39 that I am running. They recommended the 52 pilot and 170 main. I am going to try a 48 pilot tomorrow. Will post the outcome.
THANKS again.