Blower for The Demon V8

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If you mean, did I remove the gear and chuck the shaft in a drill motor and let'er rip, well that would be childish don't you think?

Of course i did! I didn't do it for very long and never tried to plug the bottom because I was getting some touching of the lobes. I still need to figure out a way to get the rotors indexed but of course I have a plan. Haven't had much time this week. Getting ready to show at the Maker Faire this weekend.

Hi Steve the blower looks awesome! Just a thought on timing lobes, GMC blowers have helical gears and one gear is shimed to rotate lobe.
 
Put that puppy on a go-cart and have some fun.
 
Finally a little progress!

I have been tied up with maintaining other engines. The Peewee V4 now has a new distributor cap, rotor, and hall sensor. She's running real nice now. The V8 had a water pump burn up. My own fault. The first design had the coolant return hose right under the fill cap so when I run it the coolant sprays out the vent hole in the cap. The coolant got low and the pump got no lube so it is now a little loose.

One thing I didn't like about the old one is the fact that the body doubles asa bearing race. The body has to be made from bronze or brass. I am going to see how a pump with sealed bearings works. With ball bearings I should be able to get away with an aluminum pump. I also am making this one like a real pump in the sense that it draws water from the inlet and feeds coolant to both sides of the pump like a real one. I don't need it to do that but I may in the future. I figured I would make enough parts for 3 pumps. I need one for the V8, one for the blown V8 and one for spare parts.


The top piece is the back side of the pump. All the passages are milled into the back of the body. The lower piece is the front of the back plate. The back plate allows the pump to span the timing cover and carries the rear bearings.

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Ally water pump sounds a lot better than brass, cos any combination of Al and Cu-based alloy in electrical contact together with water forms a very good battery. Anodising sure helps, as do the inhibitors in modern anti-freeze, but the tiniest defect and you risk your ally bits becoming a sacrificial anode, just like the Al/Mg/Zn ingots they bolts onto boats to protect the bronze propellors. I am pretty sure this is why the old brass car radiators were rubber mounted, not just because of expansion, but also to avoid electrical contact with other metals in the cooling circuit.

Stunningly awesome project - I have a LS2 V8 with bolt on Harrop blower and charge cooler (car is a Pontiac GTO to US people). Forced induction is not really a good idea without dropping the compression ratio. A little bit tricky to dial out knock and still get it through the emissions test. Hope you don't have to do micro-diagnostics on your model.
 
I have finished the 2 shafts other than the fact that the drive shaft needs to be trimmed to length. On the old pump the shafts rode in a reamed hole so the case needed to be brass or bronze. Now the shafts ride in 1/8 X 1/4 inch bearings. The o ring seal has been moved to a small pocket in the rear of the front case. I still need to make a gasket but I have my trusty template so that should go fast and then an easy finish and it should be mounted tomorrow if life will allow. I'm in a bit of a hurry because I have a metal club meeting Wednesday and I'm trying to turn it into an engine run so I would like to be ready.

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Yes same place. I fear I started too late and will be the only one bringing something to run. I am going to try to change next years august meeting to an engine run and swap.



It's on!! I just received the news letter and Rick put a notice to bring something to run. Maybe I won't be the only one.
 
Now that the other engines are running good I had time to make some new stuff. I made new carb levers and bolted them to the drums on the carb. The ball screwed into the lever but not flush like I expected. That I can fix. The socket did not pop onto the ball as far as I thought it would. That I cannot fix so I will shorten the lever up to make the adjustment. 5 minute fix, I can handle that. I also have the threaded links made to connect the throttle levers to the pivot dohickeys. I plan to make the base bracket wider so the ball wont hit the blower case. I'm only talking a .050 inch change. Not a big deal. The threaded linkage rods wont screw into the socket real far. That I expected so I cut about half of the length off that piece and it went exactly as I was hoping. The carbs are linked to the main shaft and working together so its progress.

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Well that's it for the blower. The linkage is done and working very nice. The plans have 2 changes to them
so the latest update will be out today with those 2 changes on them. The engine won't be running for a
while as I still need a crankshaft and all the fixins. I will start on all that early next week if all goes well. I
have another project that I want to finish and I'll be back.

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Looking great! Can't wait to hear it run!

Cheers,
John.
 
Steve-- I notice there is no hole for the distributor
are you going with a crank trigger set up
 
Steve-- I notice there is no hole for the distributor
are you going with a crank trigger set up


No, just haven't drilled the hole yet. I wait until the block, heads, and intake are done. Then I assemble the parts with the gaskets installed and drill both at the same time. Makes for perfect alignment. Just going with the standard distributor setup, hall sensor, CDI board. The basics. I am going to move on to making the innerds so it will be done soon.
 
Well I have the easy part done. The throws are the worst part and I am not looking forward to it.

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I am going to try the George Britnell method so I started making a fixture to hold the crank for milling operations. Once complete I can pre-mill the throws so there will be alot less to remove on the lathe. The fixture looks big but I made it work for a future project.

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