Supercharging my GJ on the cheap

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geezer101
Posts: 1869
Joined: Sat Jun 11, 2011 10:49 pm
Location: adelaide (SA)

Re: Supercharging my GJ on the cheap

Post by geezer101 »

Just wondering why you used an oval butterfly instaed of rigging an adjustable stop screw on it. You could set it to run exactly how you wanted after trial and error of adjusting the stop position.
Superscan811
Posts: 1689
Joined: Sun Mar 22, 2009 4:12 pm
Location: Sydney

Re: Supercharging my GJ on the cheap

Post by Superscan811 »

Another option would be a solenoid that is activated by your magnetic clutch switch.

That way you get no initial "blow-by", but it may act and sound a bit like a BOV when you back off..

Cheers.
starfire
Posts: 23
Joined: Sun Jun 03, 2012 10:55 pm

Re: Supercharging my GJ on the cheap

Post by starfire »

Thanks everyone for the kind words. I dont think its cleverness, more luck and perseverance, learn by doing , the same as all of us on here do. I have certainly seen some awesome projects on here that make mine quite insignificant. And Mr Superscan, that was exactly the plan B if A didnt work! I even had a garage door opener solenoid handy, just in case.
I happened on to this website if any one finds it useful... you may know about it, maybe not.
http://projectzerog.com/
Now just a question.... just what motor have I got? It seems the 4G54 is the 2 liter chain drive, is mine a 4G63 with belt drive and balance shafts? I am wondering if the twin cam head bolts straight on? All these bloody variations puzzle me. I think you Australians got the chain motors, and us here in NZ got the belt drive. Would that make yours the Astron, and mine the Sirius?
starfire
Posts: 23
Joined: Sun Jun 03, 2012 10:55 pm

Re: Supercharging my GJ on the cheap

Post by starfire »

geezer101 wrote:Just wondering why you used an oval butterfly instaed of rigging an adjustable stop screw on it. You could set it to run exactly how you wanted after trial and error of adjusting the stop position.
Actually, I was really pissed off I had to do this at all. All it needs to do is close under boost, and open under atmo, like it doesnt really need to go half way in between. I think you mean to control the SC pressure when its running?. Yes, it would do that, but the engine takes all the boost its getting without problems, 5 1/2 pounds at full throttle, so there is no reason to back it off. The damn thing actually leaks a bit too, I may rebuild it neater, just to be right.
A112H
Posts: 7681
Joined: Tue Mar 24, 2009 5:01 am

Re: Supercharging my GJ on the cheap

Post by A112H »

starfire wrote: Now just a question.... just what motor have I got? It seems the 4G54 is the 2 liter chain drive, is mine a 4G63 with belt drive and balance shafts? I am wondering if the twin cam head bolts straight on? All these bloody variations puzzle me. I think you Australians got the chain motors, and us here in NZ got the belt drive. Would that make yours the Astron, and mine the Sirius?
Not quite;
4G3* is a Saturn
4G5* is an Astron
4G6* is a Sirius

Most Saturns are 60's early 70's, 1400 and 1600cc and no balance shafts
Most Astrons are late 70's early 80's and are 2000 and 2600cc and saw the introduction of the silent shafts that we all see fit to remove!
Most Sirius are late 80's and 90's and are usually 1800 or 2000cc. These were used in EVERYTHING Mitsubishi, Trucks, vans, utes cars, forklifts and more.

You have a Sirius and yes the 4G63 DOHC head should be a bolt up fit, manifolds are another issue.
geezer101
Posts: 1869
Joined: Sat Jun 11, 2011 10:49 pm
Location: adelaide (SA)

Re: Supercharging my GJ on the cheap

Post by geezer101 »

starfire wrote:
geezer101 wrote:Just wondering why you used an oval butterfly instaed of rigging an adjustable stop screw on it. You could set it to run exactly how you wanted after trial and error of adjusting the stop position.
Actually, I was really pissed off I had to do this at all. All it needs to do is close under boost, and open under atmo, like it doesnt really need to go half way in between. I think you mean to control the SC pressure when its running?. Yes, it would do that, but the engine takes all the boost its getting without problems, 5 1/2 pounds at full throttle, so there is no reason to back it off. The damn thing actually leaks a bit too, I may rebuild it neater, just to be right.
Sorry starfire, I think I got a case of the ill communication. I get why the butterfly you designed is slightly oval now, the same reason why throtle butterflies are slighlty tapered and oval - to prevent them from jamming on the throttle 'body' wall. BTW we do have the belt drive G62B engines but they didn't make it into Australian Sigmas, they were delegated the duties of pushing around L200/L300 light commercial mitsus. Keep up with the SC R & D work! :thumpsup:
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