11-12-2021, 09:12 PM
(This post was last modified: 11-12-2021, 09:15 PM by Greig Smith.)
We built the double oil jet conversion following Mike Forrest's guidelines when we built the engine in our supercharged single seater. We managed to buy a job lot of bits which included a new Phoenix crank, it was splash fed so we then chose to drive the blower off the nose of the crank
A blank off plug was removed from the crank case next to the oil pump and replaced with a suitable fitting. The mountings were some brass bar Dad had under the lathe, we drilled it out and the top takes a home made jet which is just copper pipe but with the end tapped narrower and then drilled out. The opposite end was tapped for the mounting screws. The whole caboodle was silver soldered together and has proven to be quite durable. I annealed the copper lines and filled them with dry sand before bending over some old water pipe in the garage.
Interesting that the jet spray from now both top and bottom had to be tweaked and re-tweaked to ensure that both sets of jets have suitable spray angles for both sides of the crank by pumping paraffin via a plastic pipe into the bottom of the oil pick up using a small rotary pump driven by my battery drill. The amount of fluid flow through the jets is astounding. As per Mike Forrest the jets were all angled towards the crank which gives a near 90* arc coverage of the crank trough x 2 for the second set of jets, so I'm getting oiled big ends for approximately 180* out of 360* revolution. Austin originally had the 2 jets straight down so around 30 to 35* out of 360* and it's perfectly adequate.
1/32" overbore on the oil pump & blue printing the assembly gives over 10lbs cold, with between 5 & 6 on hot. OK granted with the 1 gallon sump it's never really very hot. I expect longer events to run the usual 1 to 3lbs which with the double oiler is more than adequate. I probably should run a smaller sump but the big finned job looks the part
No way of cleaning the second jets without pulling the sump, but regular oil changes are in order with a race car, I have to confess I've seen 6500 rpm in top gear at 6.5lbs boost and zero issues with the bearings
There's more here including duplicate pictures--> Supercharged Single Seater (austinsevenfriends.co.uk)
Eagle eyes will spot very slight differences in the brass blocks in the 2 crankcase pictures, that's because we built a second conversion for the green race car when rebuilding that engine
Season's Greetings from the Colonies
Aye
Greig
A blank off plug was removed from the crank case next to the oil pump and replaced with a suitable fitting. The mountings were some brass bar Dad had under the lathe, we drilled it out and the top takes a home made jet which is just copper pipe but with the end tapped narrower and then drilled out. The opposite end was tapped for the mounting screws. The whole caboodle was silver soldered together and has proven to be quite durable. I annealed the copper lines and filled them with dry sand before bending over some old water pipe in the garage.
Interesting that the jet spray from now both top and bottom had to be tweaked and re-tweaked to ensure that both sets of jets have suitable spray angles for both sides of the crank by pumping paraffin via a plastic pipe into the bottom of the oil pick up using a small rotary pump driven by my battery drill. The amount of fluid flow through the jets is astounding. As per Mike Forrest the jets were all angled towards the crank which gives a near 90* arc coverage of the crank trough x 2 for the second set of jets, so I'm getting oiled big ends for approximately 180* out of 360* revolution. Austin originally had the 2 jets straight down so around 30 to 35* out of 360* and it's perfectly adequate.
1/32" overbore on the oil pump & blue printing the assembly gives over 10lbs cold, with between 5 & 6 on hot. OK granted with the 1 gallon sump it's never really very hot. I expect longer events to run the usual 1 to 3lbs which with the double oiler is more than adequate. I probably should run a smaller sump but the big finned job looks the part
No way of cleaning the second jets without pulling the sump, but regular oil changes are in order with a race car, I have to confess I've seen 6500 rpm in top gear at 6.5lbs boost and zero issues with the bearings
There's more here including duplicate pictures--> Supercharged Single Seater (austinsevenfriends.co.uk)
Eagle eyes will spot very slight differences in the brass blocks in the 2 crankcase pictures, that's because we built a second conversion for the green race car when rebuilding that engine
Season's Greetings from the Colonies
Aye
Greig