crazykid
New member
Hello,ive got a 98 srx that i just put a set of ported cylinders on along with v force 3 reeds,My question is has anyone got any ideas on jetting, i tried 148-148-150 mains, 3rdclip with both washers under the clip,1.75 on the air screw. problem i am having is that it wont idle down after i press the throttle and spin the track,i have to use the choke to get it down,then it will idle fine again until i press the throttle again. I tried turning the air screw out all the way out to three turns out with very little difference. do i need to change the pilot jet or is there maybe something else wrong. Does anyone have any experience with ported cylinders and vforce reeds needing a larger pilot? Any help would be greatly appreciated,Its got me worried, Kinda. Please help
Thanks alot in advance
Thanks alot in advance
try turning your srews out to a full 2 turns. If your still having a high idle problem, go u to the next size pilot jets and start over tuning the fuel screws at 1.5 turns out on the new pilots.
crazykid
New member
Yeah i tried turning it out to 3 turns out with no difference, Just temporarily though,just to see if it made a difference. Is that too far out, as in too far out of its operating range? Well i guess ill try a larger pilot. Thanks for the reply
mopar1rules
Active member
crazykid said:
yeah, 3 turns out is too far. go up 1 size on the pilots (should be 45's if 1 up from stock) like tom stated, and try the FUEL screws (not air screws) to 1.5-2 turns out. i would return the needles to stock and try 148.8 mains on pto and center, and 151.3 main on mag side. you might end up going down on the mains to 147.5 on pto and center and 150 on mag. start richer, then look at the plug and piston wash, and adjust/decide, then from there.
crazykid
New member
yeah ill try that, thanks for the reply.
First off ,ask who ever did the porting for the jetting specs, anybody telling you jet sizes without this information is merely guessing.(very likely incorrect) The reason the idle is hanging up is its lean, the vforce reeds move more air so its lean. If you indeed went to 3 turns out from fully seated on the fuel screws located on the bottom front of carb rack then youll need to go to the next pilot jet size and start over at 1.25-1.5 turns out, this will likely cure the idle hang. Dont run the fuel screws more then 2 turns out, there will not be very much spring pressure applied and the needle could fall out from vibration. For a rule of thumb, if your more then 2 turns out and not rich enough go to the next size up pilot jet.
crazykid
New member
Thanks alot mrviper700 and all the rest that replied, yeah i have contacted the guy i bought the cylinders from but he just moved and said he doesnt know off hand but is going to look through his boxes,but do you think that what i have in so far for needle and mains will be a safe starting point(mrviper700) or anyone? would rather start a little rich than squeak it right off the bat,he said it was a trail port. Thanks again for any help
I didnt catch the cylinders being ported.
It would be best to contact the engine builder. Do you know if he did any work to the heads? You willhave to check the squish if you cant get an answer but if he didnt, I would send them into the engine builder to be cut safley to run on pump gas or maybe mrviper can help you.
But since you asked, and to be on the safe side, I would start out with 150 pto.. 148.8 center and mag on the mains. needles on the middle clip with both shims on the bottom. fuel screws 1.5 turns out with 45 pilots since the 42.5 piliots ones are giving you problems
It would be best to contact the engine builder. Do you know if he did any work to the heads? You willhave to check the squish if you cant get an answer but if he didnt, I would send them into the engine builder to be cut safley to run on pump gas or maybe mrviper can help you.
But since you asked, and to be on the safe side, I would start out with 150 pto.. 148.8 center and mag on the mains. needles on the middle clip with both shims on the bottom. fuel screws 1.5 turns out with 45 pilots since the 42.5 piliots ones are giving you problems
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mopar1rules
Active member
your mains don't sound too bad. you could try the mains i suggested to be a little safer. probably only need to jet the main on the mag cylinder, a 1/2 size larger....ex; 150 instead of the 151.3. but you deffinetly need to get that hanging idle (lean condition) taken care of. try the pilots and fuel screw suggestions, i made previously. needles should be fine in the middle w/both shims underneath.
crazykid
New member
alrighty, thanks again for the replys. Ok as far as the heads being cut i know for a fact that they arent, I bought just the cylinders ported. The guy i bought them from suggested no head mods.Now this had me alittle concerned when he told me this,as most port jobs i have read about on this forum included headwork. I checked the compression and it is at about 120 all accross with a long hose guage. Does that sound acceptable or should i have more compression. As for jetting ill go with the 148.8 148.8 151.3just to be on the really safe side,that is pretty much what i have in alredy except for the 151.3 and 45 pilots. thanks alot guys
its all depend of the porting ....i'm running 160 all across now and 120 psi seem a little low.... like mr viper says the only person who could help u out his the one who did the porting
mopar1rules
Active member
no problem. be sure to keep us posted on how it runs for ya. if you have anymore trouble, we be able to point you in the right direction. that's what this site is for.