717 xp carb jetting with proks
- Thread starter nick344
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Flame arrestor's
http://www.prok.com/
http://www.prok.com/
I personally dont care if they are or are not approved. They have been around for awhile and have been ran on many machines with out issuse. Thanks for your oppinion.
jwick86
New Member
The proks are approved. They've been around for a long time and are great filters.
Be very very careful when running after market f/a on a 717 motor without a carb brace. They have been known to crack the intake manifold from vibrations causing a lean condition blowing up the motors. Factory pipe doesn't even recommend changing from the stock air box when installing their pipe. Or any other mods since those motors are prime to seize the rear piston.
If you do run them, I wouldn't drop the pop off to 21lbs with the 2.0 and 80g. That was the recommendation for a 787 motor with R&D filters which are a little more restrictive allowing for a higher pop off. Stock pop off is suppose to be between 44-56 lbs. I would shoot somewhere for 28-32 lbs and see how your 1/4 throttle transition is. If it hesitates and clears out, its too low, bogs then goes, too high pop off.
Jetting, I'd start with a 142.5 in the mag, and a 145 in the pto. Go out 1/2 turn on your highs on both. I'd start a 75 pilot and go from there. Take your time tuning and watch your top rpm for a loss when running WOT. Thats lean and seizing. Just take your time and listen for deto (sounds like marbles bouncing inside the motor) and your rpm.
Make sure you following tuning for the carbs the way they MUST be done. Otherwise, your wasting your time. Hope this helps you some.
Be very very careful when running after market f/a on a 717 motor without a carb brace. They have been known to crack the intake manifold from vibrations causing a lean condition blowing up the motors. Factory pipe doesn't even recommend changing from the stock air box when installing their pipe. Or any other mods since those motors are prime to seize the rear piston.
If you do run them, I wouldn't drop the pop off to 21lbs with the 2.0 and 80g. That was the recommendation for a 787 motor with R&D filters which are a little more restrictive allowing for a higher pop off. Stock pop off is suppose to be between 44-56 lbs. I would shoot somewhere for 28-32 lbs and see how your 1/4 throttle transition is. If it hesitates and clears out, its too low, bogs then goes, too high pop off.
Jetting, I'd start with a 142.5 in the mag, and a 145 in the pto. Go out 1/2 turn on your highs on both. I'd start a 75 pilot and go from there. Take your time tuning and watch your top rpm for a loss when running WOT. Thats lean and seizing. Just take your time and listen for deto (sounds like marbles bouncing inside the motor) and your rpm.
Make sure you following tuning for the carbs the way they MUST be done. Otherwise, your wasting your time. Hope this helps you some.
Thanks for the info. I did download the tuning guide for the carbs. I called up PPG and they are sending me their level 1 jet kit since I am planning on letting them mill my head also. I am diffidently running a carb brace.
ok will do.
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