HI cyrustam, mine is the rotatary carb which is the same connection of the stock engine carb. The part number you got is the correct one for the slide carb. Think those are the problems you might be facing here.

1. You may conect wrongly with the new slide servo horn. i've attact a link of the picture as slide carb for you to refer.

2. You may need to re-adjust your carb position as seen in the link to allow the smooth operation of the slide carb.

Hope it'll help...

http://tsais.com/products/exhaust/tu...E1019/RR02.jpg