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Boost666s L67 Calais

BOOST666

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Just because it's common doesn't mean its a good idea, Lots of people smoke crack..
The solenoid should not leak (mine doesn't), Your car will never be using the o2 or lean cruise due to passive boost.

Also, You've ordered a Multi Layered Steel headgasket (MLS), it uses a Viton coating to seal which is VERY unforgiving to intolerances in the deck surface, without a RA spec machine (mirror finish) it will not seal. I can tell you this from first hand experience. you will need to machine the block and head which means engine out, pistons+rods+crank out. You should also order the cometic after knowing how much needs to be decked, If i were you I'd go for a really good composite head gasket and some ARP bolts and clamp it tight.

I'm not trying to be a dick just trying to save you a big headache.

I appreciate constructive criticism, thanks for your advice, I have only used composite gaskets on my cars in the past and thought I'd go for something a bit tougher this time, I have used mls gaskets previously on the trucks I work on and we only ever get the heads machined, it's a different story with the weight of the heads and much higher head bolt torques on heavy diesel applications you can get away without doing the block too... So il get a composite gaskets I really don't want to pull the block out or il end up wanting to stroke it too, which probably isn't a bad thing lol
 
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BOOST666

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Very neat car mate, I got basically the same car but in black.

Also with the convo going mine had a power loss I was chasing and in the end it ended up being the boost solenoid, I did the mod and ended up gaining 4psi.

Nice, have you got a thread going for it? Put a link here if you have one I'd like to check it out.
 

kniever

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nah i havent yet but ill get around to it one day, theres an old thread from my l67 vt i had a few years ago but i didnt have it very long and i missed it thats why i have now bought another one lol
 

PaRaDoX

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I appreciate constructive criticism, thanks for your advice, I have only used composite gaskets on my cars in the past and thought I'd go for something a bit tougher this time, I have used mls gaskets previously on the trucks I work on and we only ever get the heads machined, it's a different story with the weight of the heads and much higher head bolt torques on heavy diesel applications you can get away without doing the block too... So il get a composite gaskets I really don't want to pull the block out or il end up wanting to stroke it too, which probably isn't a bad thing lol

Yeah diesels have thicker castings due to the high compression ratio's required for auto ignition of diesel and are less prone to warping, having said this luke ran un machined, used MLS gasket on his RB30 without leakage but its a gamble, plus you have to be pushing some serious power to exceed the limits of a composite gasket and the gasket acts as a fuse in the case of detonation.

electrically or mechanically the boost bypass SOLENOID seems to stuff up regularly for people, by leaking boost pressure past the solenoid & reducing their boost pressure when it is not required.

Ok basically the M90 supercharger has a bypass valve in its inlet. It allows air to circulate around from the discharge pressure side of the blower & back to the inlet side of the rotors via the small butterfly valve. This needs to happen when the Throttle Body is in the closed position. With the Throttle Body plate in the closed position & limited air from the Intake Air Control (IAC) able to enter the inlet tract, the spinning rotors will still try to paddle air forward as the M90 is a positive displacement pump. So with a bypass valve open the air pushed forward can recirculate back up into the inlet tract for the rotors to push it through again & again, around & around. Because at idle the engine is not using (or needing) the amount of air the rotors are pushing forward, there is enough lower inlet manifold pressure to return via the bypass valve to the inlet side of the rotors. Yet still have the inlet side running at enough vacuum without cavitating (rattling & heat production). The condition at idle with the Throttle Body being closed & the blower still trying to paddle the air inside it forward. Would, without a bypass valve, create a large negative vacuum pressure, (positive inlet air pressure starvation) on the inlet side of the rotors, & cavitation (an impolsion) rattling will occur. If you didn't have a bypass valve in play the air in the blower would also heat up unnecessarily due to the resulting cavitation.

Now the Boost Bypass Valve is operated via a mechanical means. It has a air (or really a vacuum) operated diaphragm actuator hooked up to it. There are two sides to the actuator which are divided by a diaphragm, a upper (Top) chamber with light spring & a lower (Bottom) chamber. A Inlet vacuum hose is hooked up to the upper side (Top) chamber. At idle when vacuum is highest & throttle bodys are closed, vacuum in the upper chamber pulls the diaphragm up against the spring, which lifts a rod linkage connected to the Boost Bypass Butterfly Valve. The Boost Bypass opens and circulates the air & reduces boost pressure in the Lower Inlet Manifold.
As the throttle body is opened, the rpm picks up & the inlet manifold vacuum drops. As the vacuum drops the spring in the Top chamber takes over and pushes the diaphragm back down, returning the Boost Bypass Butterfly valve to its closed position (full boost).

It's a nice theory but where is the proof? IAT logs etc? I know exactly how the valve and boost bypass as I've had my L67 apart many times, on idle the intake temperatures will climb regardless of recirc. without the boost and at low rpm the entire system will still be under a vacuum, It's a factory design after all, otherwise why go with a recirc valve over a clutch pulley design?

I've never noticed any boost leakage from my L67 and the IAT's even at idle are fine, they will always climb when stationary but they are no higher than my LS1 when in traffic.



The car looks clean though, If you don't mind me asking how much is the IC setup costing and how much power are you chasing?
 

BOOST666

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borrttt

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Its a shame the kits sold here are so $$$. I bought a full size W2A kit with a 2.5" thick core from USA for $1000 inc shipping which included, pump, hoses, gaskets, heat exchanger and all install parts...sold the exchanger and bought one far larger for another $250. So spent $1300 odd for a W2A kit bigger than all available kits here. Saved big $. Mace and the other local manufacturers are good but id never buy a full kit off them...
 

BOOST666

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280rwkw is fairly high for 14psi on a m90 i'm not sure you'll see that but it will definately be a big improvement.

Yeah I know it's pretty ambitious, it's what I want out of it, but like they say, you don't always get what you want.
 

adz_vy

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Yeah I know it's pretty ambitious, it's what I want out of it, but like they say, you don't always get what you want.

Get the smallest pulley you can fit on there and get the overrun balancer. If you don't you will just do it all twice and probably have to retune it.

You won't see 280rwkw on 98 fuel but you 'might' get close on e85 and with a larger elbow and tb.

As is you will see 230rwkw tops.
 

BOOST666

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Get the smallest pulley you can fit on there and get the overrun balancer. If you don't you will just do it all twice and probably have to retune it.

You won't see 280rwkw on 98 fuel but you 'might' get close on e85 and with a larger elbow and tb.

As is you will see 230rwkw tops.

Yeah I've got a Powerbond overdrive race performance balancer
 
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