Skydog
TY 4 Stroke God
Do you have stock carb springs in slides? This sounds like a air leak in a carb line or aftermakert springs in carbs. What does the sled do with a little choke? Better or worse?
Skydog
Skydog
wantboost
Expert
not sure whats in the carbs.i just bought the sled,i will dive into the carbs tonight to see whats in there.i will try the choke thing but i know it's lean on bottom.saw 15-16 at idle on the wideband before i took it off to lend to a friend.
BigDog05
VIP Member
I don't think the pitot jet has much too do with idle. With the stock pilots and fuel screws out 2.5 turns, I idle around 14.2-14.7, but I'm way rich at low speeds at that setting. I think you may be fine around 15 at idle.
With stock pilots at 2 turns I was around 15-15.4 at idle. Seemed fine, I just went richer to try and get rid of the lean off boost problem I have.
It did not seem to matter what was in the pitot jet.
With stock pilots at 2 turns I was around 15-15.4 at idle. Seemed fine, I just went richer to try and get rid of the lean off boost problem I have.
It did not seem to matter what was in the pitot jet.
wantboost
Expert
i just ordered a new innovate wideband.don't think i should change anything till its hooked up.did you retorque your headgasket to run the big boost?
BigDog05
VIP Member
Skydog, I have billet caps and two lines from air box. I tried green springs and did not notice any change. The sled loved the silver springs at 5+ lbs of boost, throttle response was great, but it could not handle them in low no boost conditions, it would pop, sputter, fart etc.
The sled has always run great at 5+ boost conditions.
I have never been able to use choke on this sled except for 25-30 seconds on total cold start up.
ShanksRX-1. I apologize if we hyjacked your post, but you may end up with these exact same problems before you get yours all worked out.
The sled has always run great at 5+ boost conditions.
I have never been able to use choke on this sled except for 25-30 seconds on total cold start up.
ShanksRX-1. I apologize if we hyjacked your post, but you may end up with these exact same problems before you get yours all worked out.
Skydog
TY 4 Stroke God
Yea my sled did the same thing with the Sliver & green springs. I would try what we talked about.
Yea i put HD head studs in her.
Skydog
Yea i put HD head studs in her.
Skydog
Skydog
TY 4 Stroke God
Yea i dont think you will burn her down in mid but the problem is when you are riding in mid she is on the hot side so when you do lay on her she is more prone to dento. And when they start to go there is no turning back it will happend NOW!!
Skydog
Skydog
wantboost
Expert
can you hear dentonation on these motors?
Skydog
TY 4 Stroke God
no not at all buddy, you will just feel the power go away fast!!
Skydog
Skydog
wantboost
Expert
yea and then it's too late.thanks for the info
Skydog
TY 4 Stroke God
ha ha yea so so true!! Good luck have FUN and besafe!!!
Skydog
Skydog
shanksRX-1
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dont worry about highjacking. keep asking and keep answering Im reading and learning. I havn't done any tuning with my sled yet. I have worked on it all winter so I just wanted to ride it but I have a lake that is all nice and flat about 75 yards from my garrage door so I might spend a little time next weekend tuning.. I have done alot of it with banshees and two strokes. I need to get an a/f gage I guess in order to get it spot on but I can probly get closer than where I am now by riding and wrenching....
woodsrider
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Some food for thought: Although all jets do effect fuel flow throughout the throttle positions (to some degree)in general terms, the pilot jet controls idle, the needle jet controls mid-range, and the main jet controls wide open throttle. Changing needle jet size and position will effect your off idle response along with your mid range. You can also change the nozzles and this can play a factor also. However, you won't need to mess with the nozzles. The pitot jet affects the amount of pressure you are sending to the float bowls. The larger the pitot jet the less pressure the carbs will see. Fuel flow across the main jet will be proportional to pressure. Changing the pitot jet is like changing your main jet. For me 100 increment changes are about right, anything less isn't much of a change. I like to run 500-600 as my std setting.
Like Skydog said, it is important to have two lines from the intercooler to the carbs (if you take your intercooler off and blow into the single line, that Bender provided, you can watch the slides go up and down and you will also notice that they do not move in sync with each other).
If it were me, I would not do any tuning (or riding for that matter) without either an AFR or an EGT gage. With a preference to the wideband AFR. If you try to run/tune without one of these feedbacks you are guessing and it could be a costly mistake if you are not where you need to be. Each Sled is a little different. Get the pilot circuit right first, then the main jet at wot. You should then be able to adjust/change the needle jet to get the mid-range dialed in.
If your sled wasn't jetted properly before boost, then boost will only accentuate the problems.
Like Skydog said, it is important to have two lines from the intercooler to the carbs (if you take your intercooler off and blow into the single line, that Bender provided, you can watch the slides go up and down and you will also notice that they do not move in sync with each other).
If it were me, I would not do any tuning (or riding for that matter) without either an AFR or an EGT gage. With a preference to the wideband AFR. If you try to run/tune without one of these feedbacks you are guessing and it could be a costly mistake if you are not where you need to be. Each Sled is a little different. Get the pilot circuit right first, then the main jet at wot. You should then be able to adjust/change the needle jet to get the mid-range dialed in.
If your sled wasn't jetted properly before boost, then boost will only accentuate the problems.
mbarryracing
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Woodsrider, well put.
Also for guys new to A/F ratio meters. The two things that kill an 02 sensor is lead and anti-freeze. The lead from racing fuels coats the ceramic and plugs all the little pores, burned glycol does the same thing (head gasket leaks). It's like putting varnish on furniture...
Also for guys new to A/F ratio meters. The two things that kill an 02 sensor is lead and anti-freeze. The lead from racing fuels coats the ceramic and plugs all the little pores, burned glycol does the same thing (head gasket leaks). It's like putting varnish on furniture...
