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Anyone custom intake the 0470b?

Bamasoflorunner

Well-known member
Wanted to know if anyone ever customize the intakes on the 0470b and basically reverse the gpu intake to the underside of a 0470b and use a Ma 4-5 marvel updraft to feed it?
 

Bamasoflorunner

Well-known member
Sooo no one has taken Gpu spider inverted it, fabbed brackets to hold it on a o470 modded a ma4-5 updraft to fit to bypass to traditional 470 set up? I know later 470s have a spider but has other fab issues.
 

Gary S

Well-known member
Why would you want to? Be kind of hard to change oil with that spider hanging down under oil pan. Also more hair flow disturbance to prop.
 

Bamasoflorunner

Well-known member
I would imagine the oil change can be fabbed to not be an issue. The air flow would be minimal, my GPU oil pan in theory disrupts more than a fabbed upside down gpu spider would cause and shouldn’t block the drain plugs on the 470 pan either. It would also eliminate the crazy plumbing and balance tube in the back on the 470 set up and probably be more efficient and balanced in delivering air/fuel charge when paired with the updraft carb. I have a 470 I’m gonna rebuild I guess I’ll try it and post anything that comes of it or convert to the 470 spider that the later models have. Thanks for chiming in.😎
 

Gary S

Well-known member
If your looking for better efficiency I hear flipping original carburetor mount over and converting it to a 500 holley is more efficient. And for sure a ground power oil sump disrupts more air to the prop than a aircraft.
 

John Fenner

Well-known member
The O-470- B should have the intake logs that run full circuit with a crossover tube at the prop end, a set of elbows under the gear case end, tucked in, if you want better or best efficient fuel economy, as Gary stated above, a 500 Holley adapted plenum and some fine tuning will be best.
 

Bamasoflorunner

Well-known member
Sounds good you guys are awesome! When I get done with tear down and rebuild, then new stand to replace the gpu I’ll post up what I come up with. The Gpu is running strong for the moment so this will be the future power plant option if I don’t just convert the gpu. I really want to go to a true ac motor.
 

Slidin Gator

Well-known member
Bamasoflorunner said:
The Gpu is running strong for the moment so this will be the future power plant option if I don’t just convert the gpu. I really want to go to a true ac motor.

It is always best to be building your next motor while your present motor is going strong. It's just like looking for a job, you are most likely to land a better and/or higher paying next job if you don't need it.

Just go all in and don't cut corners, the end result will impress and probably be lower total cost.
 

John Fenner

Well-known member
500 Holley plenum.
 

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John Fenner

Well-known member
This thing runs great, power valve blocked, #76 jets recommended, sips fuel at a cruise, the MA 4-5 or MA-6 is a glorified tractor carb, can fine tune these.
 

John Fenner

Well-known member
I built this one and many others, mainly for 220 conversions, I would have to get a b case to mock up with if you are interested, I will start gathering materials.
 

Bamasoflorunner

Well-known member
If you don’t mind I’ll pm you when I get closer, I’m at a minimum 6 months out if things don’t get any crazier in my life, got one son graduating going to UCF and other pulls in life at the moment. I just finished tig welding a vertical rebuild stand so I can start taking top end off and pan to investigate what’s going on in the motor. May need someone do the bottom inspection rebuild (do you do these?). The previous owner said he idled out from ramp and it was running rough so he turned around and shut it off. One cylinder has oil in it (valve guides prob) and another has top piston damage old/new from prob stuck valve, motor turns over and valve appears to travel normally as it sits but maybe be bent. So I know I wanna service or replace these two, looking at Gibson aviation maybe. All other cylinders look great. Initially I was gonna convert the GPU but would rather move to AV even though it would be easier to do my GPU which is a double mag. All my measurements seem to pan out on doing a stand for this 470 and doing the starter alternator kit at the prop end. Decisions but I gotta get these areas addressed before the intake but def will pm you for that. Your in Broward area correct? Thank you again for your wealth of information, not the first time you’ve helped out providing input and direction to me.😎
 

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subendofb

Member
The GPU is running strong for the moment so this will be the future power plant option if I don’t just convert the GPU or fishing lures. I really want to go to a true ac motor.
 
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Bamasoflorunner

Well-known member
I built this one and many others, mainly for 220 conversions, I would have to get a b case to mock up with if you are interested, I will start gathering materials.
Here’s the pic of piston
 

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John Fenner

Well-known member
Looking at the cylinder head, the exhaust seat bore has been peened, best to replace seat with new oversized seat or replace jug.
 
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