Smog pump to pressurize oil tank on 2-stroke MOP conversion?
08-16-05, 02:56 PM
#1
Thats not an FC...
Thread Starter
Join Date: Apr 2001
Location: spring hill, Fla
Posts: 844
Likes: 0
Received 0 Likes
on
0 Posts
Smog pump to pressurize oil tank on 2-stroke MOP conversion?
i was just wondering if taking a pressure bleed from the smog pump on the front of the engine would be beneficial for force feeding the 2-stroke oil to the OMP when using the Rotary Aviation 2-stroke adaptor or modified OMP plate?
Rotary aviation specifies that the oil level should be at a height of 6" or greater over the feed nipple on the OMP adaptor plate. on NA's, the more oil, the better. Oil typically has a detrimental effect to the octane level of gasoline by lowering it and reducing the anti-knock index. while this is counterproductive for piston and all forced induction engines, its beneficial to non-turbo rotaries. non-turbo rotaries have a history of enjoying lower octane levels as the anti-knock index is lower and more volatile under pressure. this means it has a faster traveling flame front in the combustion chamber and will burn more efficiently and make more power. ive also confirmed this by speaking to Rob golden at Pineapple racing. the Rotary power race cars that were campaigned in the IMSA-GTU racing series were non-turbo and the fastest rotary powered cars were easily identified by noting how much smoke came from the exhaust. the premixed gasoline that these cars ran on typically had an equivalent octane rating of about 78-79.
on that note, ive always premixed at a ratio of about 1:60 or 1:64, about 2 ounces of TCW-3 ashless 2-stroke oil for every gallon of fuel added. there was no additonal amount of exhaust smoke in contrast to the stock OMP system due to the blend of the oil. id like to switch to Sea-Doo Rotax 2-stroke oil. the Rotax oil is pretty expensive, but its designed to significantly reduce the carbon and ash desposits as it is specified for use w/ the Sea-Doo Rotax valve design. this is a Rotating valve similar to the design of a peritrochoid rotor which "opens" and "closes" the ports on the Rotary engines. it controls the intake/exhaust operation on the Sea-doo 2-stroke engines. the rotax oil is designed to virtually eliminate the carbon and ash deposits enountered w/ typical TCW-3 oils to ensure Proper operation of the Sea-Doo engines.
considering that the rotax valve on the sea-doo engines operate on a virtually identical premise as ou engines, i think that the Rotax oil would probably be the BEST option for use with a 2-stroke operated Rotary engine.
but, back to my idea; im considering teeing off of the smog pump output port to increase the perceived atmospheric pressure inside the oil tank to enhance the feed rate and pressure to the OMP adaptor plate. i feel that even a few psi increase inside the oil tank will ensure positive oil flow to the OMP adaptor plate, regardless of tank mounting height, oil level, oil feed line diameter and length. im not sure how much pressure the stock Smog pump puts out, but i do beleive it is a positive displacment design with only the condition of the internal seals affecting its efficiency and output. utilizing the positive pressure that the smog pump puts out, i should be able to increase the volume of oil admitted by the injectors and hopefully acheive my desired 1:60-1:64 mixture ratio.
what do you guys think?
thanks
chris
Rotary aviation specifies that the oil level should be at a height of 6" or greater over the feed nipple on the OMP adaptor plate. on NA's, the more oil, the better. Oil typically has a detrimental effect to the octane level of gasoline by lowering it and reducing the anti-knock index. while this is counterproductive for piston and all forced induction engines, its beneficial to non-turbo rotaries. non-turbo rotaries have a history of enjoying lower octane levels as the anti-knock index is lower and more volatile under pressure. this means it has a faster traveling flame front in the combustion chamber and will burn more efficiently and make more power. ive also confirmed this by speaking to Rob golden at Pineapple racing. the Rotary power race cars that were campaigned in the IMSA-GTU racing series were non-turbo and the fastest rotary powered cars were easily identified by noting how much smoke came from the exhaust. the premixed gasoline that these cars ran on typically had an equivalent octane rating of about 78-79.
on that note, ive always premixed at a ratio of about 1:60 or 1:64, about 2 ounces of TCW-3 ashless 2-stroke oil for every gallon of fuel added. there was no additonal amount of exhaust smoke in contrast to the stock OMP system due to the blend of the oil. id like to switch to Sea-Doo Rotax 2-stroke oil. the Rotax oil is pretty expensive, but its designed to significantly reduce the carbon and ash desposits as it is specified for use w/ the Sea-Doo Rotax valve design. this is a Rotating valve similar to the design of a peritrochoid rotor which "opens" and "closes" the ports on the Rotary engines. it controls the intake/exhaust operation on the Sea-doo 2-stroke engines. the rotax oil is designed to virtually eliminate the carbon and ash deposits enountered w/ typical TCW-3 oils to ensure Proper operation of the Sea-Doo engines.
considering that the rotax valve on the sea-doo engines operate on a virtually identical premise as ou engines, i think that the Rotax oil would probably be the BEST option for use with a 2-stroke operated Rotary engine.
but, back to my idea; im considering teeing off of the smog pump output port to increase the perceived atmospheric pressure inside the oil tank to enhance the feed rate and pressure to the OMP adaptor plate. i feel that even a few psi increase inside the oil tank will ensure positive oil flow to the OMP adaptor plate, regardless of tank mounting height, oil level, oil feed line diameter and length. im not sure how much pressure the stock Smog pump puts out, but i do beleive it is a positive displacment design with only the condition of the internal seals affecting its efficiency and output. utilizing the positive pressure that the smog pump puts out, i should be able to increase the volume of oil admitted by the injectors and hopefully acheive my desired 1:60-1:64 mixture ratio.
what do you guys think?
thanks
chris
