Looking for some options. I have a stock 77 srx 440 that I'm looking to drag race. Looking to simplify the carbs. So should I block off the power jets or put a set of 44 mikuni carbs on it? (Which rules allow). Where should a guy start with for jetting? Change to the timing? Any other changes to help out with performance? Thanks!!!
YAMMIEGOD3:16
Active member
don,t touch timing on a 77 until you check afew things. timing was already advanced on this snowmobile. carb size is up to you and your rules. but yes if ya run stock set -up. block power jet and up main jet. 3:16 (yammie tony)
Tony...what have blocked them with?
#01YamahaNut
New member
new to this , is this a forum for the old 440 srx I need an engine identified it was in a 80srx with 80heads and jugs probem is it has 10mm jug bolts and 18mm wrist pins so im thinking 76 or 77 or early 78 numbers on case are Rt339 008471 any help on what it is or how to decode would be appreciated sorry if im interrupting on someone
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Throttle Junkie35
New member
339 would be 76 i believe