This one kinda serves it's purpose but i still want better reliability. I'll try modding the factory carb this evening and get a run in with a stocker from the shop so i know what was gained or lost, also going to swap coils.
PSI or corrected compression ratio? Feels like 160-180psi on the cord, corrected compression ratio is 7.4:1 PSI measurement is nearly useless as a tuning metric in my eyes unless you are trying to derive a polytropic exponent from your cylinder layout.
@@Super-Dave-Outdoors Gasket delete or + shave the base? I know Bodie has been deleting+.010 off the base. I thought 7.4 was REALLY light when I read the manual on mine.
620 is 6.9:1 stock. 590 is 7.2 stock (109 roof i think) 80,124,104 with 65% bore width exhaust. 7.4:1 CCR .035 off the base .012 base gasket and about .020 from the chamber. The chamber on these is huge and you have to make the compromise of compression or port duration. This one wins in compression and duration over the stock saws. The one that beat it uses stock 620 numbers and different transfer angles. Higher CCR and lower roof too.
What’s with ported saws and failing oil pumps 😆 Just got a ported 590, and oil pump just failed also! Have had probably around 15 non-ported 590/620’s through my hands either bought, sold, flips, repairs, etc… and never seen a bad oil pump yet till now. Have you came close to free-porting with .035 off the base? Is the .012 gasket a stock one, ever tried the .006 performance gasket from Duke’s?
.012 is stock gasket. Dukes gasket material is fine. .006 wont make a noticable difference up or down. That oil pump was shot before the saw was ported. Every used one i have purchased has a crapped out oil pump. You will catch the ring of death in the top of the cylinder before freeporting becomes an issue. Like it sits it does not free port. If i could get away with more out of the chamber i would see how far you can push free porting before it becomes a problem.
Marketplace ad would say “Ported saws very fast, NOT FOR BEGINNERS” look like pretty good runners, definitely think aftermarket carbs are hit or miss.
Hello sir. I have always wondered about the AM 620 carbs. Cool that they exist but a bummer if they are flaky.
@@oakiewoodsman 👊
This one kinda serves it's purpose but i still want better reliability. I'll try modding the factory carb this evening and get a run in with a stocker from the shop so i know what was gained or lost, also going to swap coils.
👍👍all looked like pretty good runners to me!
Indeed!
😁
Definitely better than stock but i want improvements not to go backwards.
👍🆙SD😁
Hello friend
@@oakiewoodsman 😊👊
What compression did you end up at?
PSI or corrected compression ratio?
Feels like 160-180psi on the cord, corrected compression ratio is 7.4:1
PSI measurement is nearly useless as a tuning metric in my eyes unless you are trying to derive a polytropic exponent from your cylinder layout.
@@Super-Dave-Outdoors Gasket delete or + shave the base? I know Bodie has been deleting+.010 off the base. I thought 7.4 was REALLY light when I read the manual on mine.
620 is 6.9:1 stock.
590 is 7.2 stock (109 roof i think)
80,124,104 with 65% bore width exhaust. 7.4:1 CCR
.035 off the base .012 base gasket and about .020 from the chamber.
The chamber on these is huge and you have to make the compromise of compression or port duration.
This one wins in compression and duration over the stock saws.
The one that beat it uses stock 620 numbers and different transfer angles. Higher CCR and lower roof too.
What’s with ported saws and failing oil pumps 😆
Just got a ported 590, and oil pump just failed also! Have had probably around 15 non-ported
590/620’s through my hands either bought, sold, flips, repairs, etc… and never seen a bad oil pump yet till now.
Have you came close to free-porting with .035 off the base?
Is the .012 gasket a stock one, ever tried the .006 performance gasket from Duke’s?
.012 is stock gasket. Dukes gasket material is fine. .006 wont make a noticable difference up or down.
That oil pump was shot before the saw was ported. Every used one i have purchased has a crapped out oil pump.
You will catch the ring of death in the top of the cylinder before freeporting becomes an issue. Like it sits it does not free port. If i could get away with more out of the chamber i would see how far you can push free porting before it becomes a problem.