Alright, this is going to be detailed with symptoms so bear with me.
I have an intercooled 2019 rmk with boondocker sidekick intercooled plus the deep snow tunnel exit exhaust. Idaho billet bd head. The newest 61 gram base weights from bd with the -8 or weight screws in it. 140/310 primary spring w/ 100 miles on it. Yellow black secondary with whatever bd/venom 44/40 helix is supposed to be in it, assuming 1400 miles on sec spring. 6-10 lbs wastegate. No idea what pressure it runs at tho. My base elevation is 9,900 feet.
I usually mix 50/50 avgas non lethanol. Today I had 5 gallons of 88 with a bunch of torco accelerator in it with leftover 50/50 mix.
Today was 3 feet of fresh wettish powder. Not super heavy but not light.
If I pin it wide open from a stop it will pull 8550, and QUICKLY settle to 8100 then 8050 and sit there with the -8 weight pins. It will not backshift while moving, back over 8000 rpms. I started the day with the -12 (longest) pins and it would go to 8300 and then 7850. But here is the biggest problem: if it hold it wide open long enough a GAWDAWFUL motor noise happens like the loudest bog/lean/intake backfiring/ 7000 rpm drop thing, I don't even know how to describe the sound.
Sometimes if happens in 3 seconds of wot. Sometimes it doesn't for 10 seconds. BUTTTTT if it's up a hill it WILL do the awful noise/rpm drop anywhere from 7400 to 6800 usually pretty quickly. But sometimes it powers thru the hill and barely kinda bogs. Let off, pin it wot again and anywhere from 1 to 5 seconds it will bog/drop again. Wtf is happening? It sometimes still happens with 50/50 mix.
It will bog/rpmdrop noise almost instantly on a really steep hill, like in the ravine we were screwing around in today, when climbing in an out of short but super steep sections. Like less than 15 yard climbs but maybe 50-60 degree inclines.
1) bad fuel pump
2) bad fuel sock
3) deto sensor is pulling timing/rpm aka my octane of fuel is just wrong
4) secondary spring is weak and is overloading sled.
5, 6,7,8) comvination of all the above, hook up boost gauge and fuel pressure gauge to see wtf is going on.
Thanks.
I have an intercooled 2019 rmk with boondocker sidekick intercooled plus the deep snow tunnel exit exhaust. Idaho billet bd head. The newest 61 gram base weights from bd with the -8 or weight screws in it. 140/310 primary spring w/ 100 miles on it. Yellow black secondary with whatever bd/venom 44/40 helix is supposed to be in it, assuming 1400 miles on sec spring. 6-10 lbs wastegate. No idea what pressure it runs at tho. My base elevation is 9,900 feet.
I usually mix 50/50 avgas non lethanol. Today I had 5 gallons of 88 with a bunch of torco accelerator in it with leftover 50/50 mix.
Today was 3 feet of fresh wettish powder. Not super heavy but not light.
If I pin it wide open from a stop it will pull 8550, and QUICKLY settle to 8100 then 8050 and sit there with the -8 weight pins. It will not backshift while moving, back over 8000 rpms. I started the day with the -12 (longest) pins and it would go to 8300 and then 7850. But here is the biggest problem: if it hold it wide open long enough a GAWDAWFUL motor noise happens like the loudest bog/lean/intake backfiring/ 7000 rpm drop thing, I don't even know how to describe the sound.
Sometimes if happens in 3 seconds of wot. Sometimes it doesn't for 10 seconds. BUTTTTT if it's up a hill it WILL do the awful noise/rpm drop anywhere from 7400 to 6800 usually pretty quickly. But sometimes it powers thru the hill and barely kinda bogs. Let off, pin it wot again and anywhere from 1 to 5 seconds it will bog/drop again. Wtf is happening? It sometimes still happens with 50/50 mix.
It will bog/rpmdrop noise almost instantly on a really steep hill, like in the ravine we were screwing around in today, when climbing in an out of short but super steep sections. Like less than 15 yard climbs but maybe 50-60 degree inclines.
1) bad fuel pump
2) bad fuel sock
3) deto sensor is pulling timing/rpm aka my octane of fuel is just wrong
4) secondary spring is weak and is overloading sled.
5, 6,7,8) comvination of all the above, hook up boost gauge and fuel pressure gauge to see wtf is going on.
Thanks.
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