007redline
New member
Jetting my ported 2001 SRX questions??
newbie question... Would like some jetting info...just learning but things I'm interested in I learn quick, If you don't ask you will never know..So I apologize for any stupid questions...lol
Jetting questions...??
Pilots jets is ideal to 1/4 throttle correct..so you'd have to let it ideal and drive around to 1/4 throttle to check and see if they're burning correctly
&
Main Jetting you'd have to drive around 1/4 to wide open then check your reading off your plugs for that as well correct..
Should prob run new plugs to get a better reading each time eh..
Check piston wash for each and adjust from there...
Is this correct more or less or am I not thinking straight..lol
Also what's a step down from 155 Mains is it 152.5's
and a step down from 45's 42.5's
Trying to dial in my sled for jetting before clutch tunning begins...started a new thread on jetting so I'll give ya the details again..
MrViper Heavy ported cylinders, plained heads with .56 squish
w/140-143 p.s.i compression
high test fuel with added 10-15 points octane booster
Cold air kit with middle shelf removed (will be intalling it back in asap)
155 Mains across the board w/45 Pilots clip on pos 3
Running really rich with lots of piston wash
Got pretty stupid and went from one extreme to another
Got brave and put 150 mains and 40 pilots also was 10 degrees colder that day..plugs turned yellowish white and pistons were on the verge of very very lean but caught it in time... was running on new plugs for about 7 minutes so it's kind of hard to read new plugs that quick but that's what color they were..
What's a step down from 155's and 45's
I was thinking 152.5's and 42.5's something like that
newbie question... Would like some jetting info...just learning but things I'm interested in I learn quick, If you don't ask you will never know..So I apologize for any stupid questions...lol
Jetting questions...??
Pilots jets is ideal to 1/4 throttle correct..so you'd have to let it ideal and drive around to 1/4 throttle to check and see if they're burning correctly
&
Main Jetting you'd have to drive around 1/4 to wide open then check your reading off your plugs for that as well correct..
Should prob run new plugs to get a better reading each time eh..
Check piston wash for each and adjust from there...
Is this correct more or less or am I not thinking straight..lol
Also what's a step down from 155 Mains is it 152.5's
and a step down from 45's 42.5's
Trying to dial in my sled for jetting before clutch tunning begins...started a new thread on jetting so I'll give ya the details again..
MrViper Heavy ported cylinders, plained heads with .56 squish
w/140-143 p.s.i compression
high test fuel with added 10-15 points octane booster
Cold air kit with middle shelf removed (will be intalling it back in asap)
155 Mains across the board w/45 Pilots clip on pos 3
Running really rich with lots of piston wash
Got pretty stupid and went from one extreme to another
Got brave and put 150 mains and 40 pilots also was 10 degrees colder that day..plugs turned yellowish white and pistons were on the verge of very very lean but caught it in time... was running on new plugs for about 7 minutes so it's kind of hard to read new plugs that quick but that's what color they were..
What's a step down from 155's and 45's
I was thinking 152.5's and 42.5's something like that
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9801srx
Member
your correct for the pilot circuit. the needle is for 1/4 to 3/4 so you do a 600 to 700 foot run at half throttle and check piston wash. if thats good you move to the main.which is 3/4 to full throttle.do a full throttle pull for 600 to 700 feet and check wash and adjust acordingly. i find piston wash is the only true indicator.your correct on the one size down 152.5 and 42.5. also when i get piston wash that i like in 600-700 ft pulls then i go to a 1/4 mile and recheck again.
YAMMIEGOD3:16
Active member
NEEDLES ARE REALLY INPORTANT. I BELIEVE THEY ARE LIFELINE OF A MOTOR. THATS WHERE PROBLEMS CAN START AND ONCE YOUR AT MAIN ITS TO LATE. 3:16 (yammie tony)
007redline
New member
YAMMIEGOD3:16 said:
Needle is clip position 3 w/plastic shims under clip...should be rich if any there eh..??
Have you thought of asking the guy that built the motor for a place to start? Pretty tough to jet a sled through the computer, most guys that build motors can give you a place to start, but it's up to you to dial it in. What my sled likes and will live with, yours might not and so on. Don has always been helpful on anything I've used that had his name attached to it. Why don't you give him a try.
Couple more things, old plugs will show color faster/better than new ones. Hard to read a new plug. Different fuels and additives(octane boost) will color plugs differently. 3 with both under on the needles is may or may not be enough fuel. depending on the porting and the airbox mods you might need to four with both over, or one over and one under. Again it's your sled, your fuel, etc...
You can also get jets that break between the normal 155/152.5/etc... Might have to go that route if 155 is rich and you want a little more than the 152.5's.
Couple more things, old plugs will show color faster/better than new ones. Hard to read a new plug. Different fuels and additives(octane boost) will color plugs differently. 3 with both under on the needles is may or may not be enough fuel. depending on the porting and the airbox mods you might need to four with both over, or one over and one under. Again it's your sled, your fuel, etc...
You can also get jets that break between the normal 155/152.5/etc... Might have to go that route if 155 is rich and you want a little more than the 152.5's.
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