Smog pump supercharger

Thepaetsguy

Well-Known Member
How are you venting the crank case?
An actual PCV valve to manifold vacuum might help with seals and side cover gasket.
I’m not venting the crankcase the vent is being used as a fuel pulse signal. The sidecover seals haven’t been an issue this engine leaks zero oil. I did vent the crankcase but in turn lost all fuel pressure. I still don’t think I can pulse off the intake boost fitting as there is 25psI in that tube.

Boost reference came up in a conversation I was having with someone recently and they wondered if I used a metal pulse pump off the intake if that would be like a boost reference? 25psi of boost 25psi of pulse pump fuel pressure? I told him that didn’t sound right at all...
 
If your carb is in atmosphere (draw through)
Your fuel pressure should be referenced to atmosphere. If you pressurized the carb, then you need fuel pressure referenced to boost pressure. You are correct.
I asked about venting because with boost, it seems like blow by would add gas to your oil.
 

Thepaetsguy

Well-Known Member
If your carb is in atmosphere (draw through)
Your fuel pressure should be referenced to atmosphere. If you pressurized the carb, then you need fuel pressure referenced to boost pressure. You are correct.
I asked about venting because with boost, it seems like blow by would add gas to your oil.
It is extremely hard on spark plugs and I figured that was due to oil getting into the fuel and running a bit rich. So I’m basically 100% stuck with pulsing off the crankcase.

I knocked 100cc off this guys math because my smog pump is probably alot less efficient then this guys arm300 and got
200cc/163cc = 1.22
1.22 * 14.7 = 18.0psi
18-14.7 = 3.3psi total boost if I made my crank pulley twice it‘s size. I really need something to put this engine on now.

71B650E0-99F2-4466-8D75-379BA718BF0A.jpeg
 
I have said this before. If you put a load on the crankshaft, you slow it down, and your boost pressure will increase, because basically, there is more time to build pressure in the intake. Right now, with no load, the engine is just spinning like crazy.
 

Thepaetsguy

Well-Known Member
https://www.youtube.com/shorts/ZI7WlNCj5XQ

Next I’d like to install this Horstman 150 weld cam and springs. Once the cam is in I’ll back off the timing yet again and finally go for it and 1to1 ratio the pump.

I made a much more free flowing exhaust and picked up some 93 instead of 87 octane. I think this helped a lot with top end response. The gauge is broken in this video.

The crank seal hit me i’m fine :scooter::scooter:

edit: Volume/Language warning ahead.. The tube exhaust is loud and I was in a bit of shock.

42C6CDD6-963A-4599-A184-F5E6224A0F75.jpeg 2CED6F9E-53D4-48E0-AA16-01FEB5AB700C.jpeg
 

Thepaetsguy

Well-Known Member
I really don’t want to buy a $51 set of extended lifters... And we have well established I do not care if this engine burns down.

I’m mostly worried about my arm. I can lay a dot of weld on a junker set of valves to extend them. Or would I put the dot on the lifter to extend it?

Horstman 150 weld cam
280/300 lift C114BE43-C102-479E-AB9D-0ABD3AE4F44D.jpeg 49D41F1E-AB54-471A-AC25-CD74707EBFB4.jpeg
 
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