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DIY M62 supercharger build... stage 2

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gray Graham Moore
CAMBRIDGE, CAMBRIDGE, UK   GBR
i'll take a better look when i get the old one off.

your post 105 - are you referring to feeler gauges where i had compromised gasket ? or somewhere else adrian? if former, will need to wait till i take the old charger off - and that will be when the sun comes out a bit. prob early march unless the vac leak i think i have gets much worse.

at the moment i am making new bits up to support the carb in a different way so i can whip it off quickly if needs be, although that was the one gasket i was worried about which appears to have held well.

G

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pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
You can check for gaps there too but I was referring to the rotor to housing and rotor to rotor clearances... to get an idea of the condition of your supercharger.

Adrian



Home built Eaton M62 Supercharger with 7.6psi boost, 8:1 compression, custom "supercharger" cam from Schneider Cams, Mikuni HSR48 Carburetor, Chevy Cavalier 1.6 rocker arms, Maxspeeding rods with Teflon wrist pin buttons, custom aluminum cold air intake, CB Performance computerized ignition, Fidanza 9 pound flywheel, 1.44 exhaust valves in 48cc chamber head, matched manifolds, 2 1/4" exhaust system.

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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Had the SC off last 12000 km and five years ago (a new km speedo at the same time) New engine but the blower had done about 40,000miles in 10 years on the old engine. Looked perfect then, no marks on the lobes. I do service the large K&N regular, due to our unmade road. Not noisy and boost seems OK. As you can see it has not done a lot of work lately, because of the V8 GT on the road as well and my old Jag sedan that I go to club meetings in (all on club plates.) The supercharged roadster is still the most fun and will get a lot more use when we get through this run of 44*c. Jan and Feb are just too hot in the roadster. Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine "3.9L Rover" early in 2016 with high comp pistons and a few other nice bits, plus a T5 ford trans. Started on the body late 2016 and complete late 2017, Did all the work myself, mechanical, body. paint etc.
Finished and going well, great to drive and quick. Now has a nice 3.23 LSD.

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gray Graham Moore
CAMBRIDGE, CAMBRIDGE, UK   GBR
Adrian

i put the numbers in post #97.

yellow clearance ~ 7 thou and red~ 17

my 17 was max gauge i could just about get between rotors when meshed. just the tip really due to curvature. if i looked and measured just looking from top i would say more like double that as there is a slight bevelling.

so order of magnitudes same as yours i would surmise.

G

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pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
My MG is now running on its new Japanese carburetor. It's idling at 800rpm and 12:1 with the pilot air screw out 2 1/2 turns so that's pretty close to spot on. I'm seeing almost 17" of vacuum at idle.

It seems to be very rich otherwise. Hard to tell sitting in the workshop. It goes to 10:1 at 3000rpm in neutral.

The throttle return spring was inadequate. I moved the spring attachment point and sorted that. The choke worked well. As supplied it would be on and off but by using the T handle on the dash it works great. It has the same progressive action as the SU but in a shorter range of motion.

So... now I have to wait for spring to tune it.

Adrian



Home built Eaton M62 Supercharger with 7.6psi boost, 8:1 compression, custom "supercharger" cam from Schneider Cams, Mikuni HSR48 Carburetor, Chevy Cavalier 1.6 rocker arms, Maxspeeding rods with Teflon wrist pin buttons, custom aluminum cold air intake, CB Performance computerized ignition, Fidanza 9 pound flywheel, 1.44 exhaust valves in 48cc chamber head, matched manifolds, 2 1/4" exhaust system.



Edited 1 time(s). Last edit at 2019-01-02 10:57 AM by pinkyponk.


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MGB M62 supercharger with cold air intake.jpg    53.8 KB
MGB M62 supercharger with cold air intake.jpg

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gray Graham Moore
CAMBRIDGE, CAMBRIDGE, UK   GBR
adrian
came across this site - re rotor coatings

http://www.orioncoat.com/industrial-applications/products/supercharger-rotor/

pulled my charger today. bad leak around inlet<->head (exhaust manifold) gasket

also the pic below - owner tried pressing rotors out to do bearings. ouch!

G


Attachments:
M62 - BROKEN.JPG    38.2 KB
M62 - BROKEN.JPG

Machine_Design_-_Conformable_Coating_Supercharges_.pdf    399.1 KB
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pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
Took the car for it's first drive with the new carburetor, new rocker arm system and shortened supercharger today. It idles really well but it's way too lean when I step on it. If I fiddle with the throttle long enough I can get it to rev up and it really flies!

Now I need to get the Mikuni dialed in!

Adrian



Home built Eaton M62 Supercharger with 7.6psi boost, 8:1 compression, custom "supercharger" cam from Schneider Cams, Mikuni HSR48 Carburetor, Chevy Cavalier 1.6 rocker arms, Maxspeeding rods with Teflon wrist pin buttons, custom aluminum cold air intake, CB Performance computerized ignition, Fidanza 9 pound flywheel, 1.44 exhaust valves in 48cc chamber head, matched manifolds, 2 1/4" exhaust system.

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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Adrian the first things to get right are bottom then top end top, Sounds like idle is right, so top end is next. I found drilling the main jet to .125" helps but the needle is too restricted until you fit the Y8 needle jet.
You can then start playing needle profiles. "Dont touch" the parallel part. I did mine with the needle clip in the center slot as it gives you scope for tuning when very close to right. The wide band A/F is handy but not as much as with the SU and seat of pants tuning takes over. The pilot jet also affects the mixture (slight) right through the range and is something to keep in mind. Set the acc pump for max and squirting at the needle.
The needle rubs down easy so be carefull, and make sure the choke is seating hard closed as it can throw things out if not. I am sure you will be right.. Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine "3.9L Rover" early in 2016 with high comp pistons and a few other nice bits, plus a T5 ford trans. Started on the body late 2016 and complete late 2017, Did all the work myself, mechanical, body. paint etc.
Finished and going well, great to drive and quick. Now has a nice 3.23 LSD.

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pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
Yes, idle seems pretty good. I do have the Y8 jet installed. And the main jet was drilled to .125" . I moved the needle clip to the top groove futzing with it over the winter. I ran out of time today to set it right. So step one will be resetting that. It got richer as it revved up and pulled quite hard but on my little back street there isn't much time to drive and read gauges... so I didn't get a reading.

I'm very limited in where I can go at the moment. The roads have frost heaved the worst I've ever seen this year. The B just couldn't make it through until they settle back down.

I was finding it slow to start with the choke the last few times so today I pumped the throttle 2 times and it fired up instantly... but I did have the choke on also. I'll try starting it with 2 pumps without the choke tomorrow.

Adrian



Home built Eaton M62 Supercharger with 7.6psi boost, 8:1 compression, custom "supercharger" cam from Schneider Cams, Mikuni HSR48 Carburetor, Chevy Cavalier 1.6 rocker arms, Maxspeeding rods with Teflon wrist pin buttons, custom aluminum cold air intake, CB Performance computerized ignition, Fidanza 9 pound flywheel, 1.44 exhaust valves in 48cc chamber head, matched manifolds, 2 1/4" exhaust system.

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pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
wrong thread


Adrian



Home built Eaton M62 Supercharger with 7.6psi boost, 8:1 compression, custom "supercharger" cam from Schneider Cams, Mikuni HSR48 Carburetor, Chevy Cavalier 1.6 rocker arms, Maxspeeding rods with Teflon wrist pin buttons, custom aluminum cold air intake, CB Performance computerized ignition, Fidanza 9 pound flywheel, 1.44 exhaust valves in 48cc chamber head, matched manifolds, 2 1/4" exhaust system.



Edited 1 time(s). Last edit at 2019-03-13 07:46 PM by pinkyponk.

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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
That would surely be a quality fault as your use would not be any harder than designed. As for the Mikuni, I dont need the choke at all but we dont ever get the extreme low temp that you do. I still have the Harley D cable attached under the bonnet. When working the needle originally it felt I was getting nowhere until I got close then little bits made all the difference.

Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine "3.9L Rover" early in 2016 with high comp pistons and a few other nice bits, plus a T5 ford trans. Started on the body late 2016 and complete late 2017, Did all the work myself, mechanical, body. paint etc.
Finished and going well, great to drive and quick. Now has a nice 3.23 LSD.

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