443 replies to this topic

[slindborg]

These electric pumps do have a limited life span, I wonder how many charge cooler pumps are actually working.   There are in line flow meters that can tell you if it's working, or I guess a system to measure resistance across the pump. I'll have a play and see where I get to

Do it how the switched loads are on the PCM... Ground through a 0.1ohm resistor and measure voltage on it to determine the current. Flow sensor would make lots of sense for system testing anyway.

[smiley]

I check if i got flow in my cc tank regularly.

 

[techieboy]

I doubt very much the tank location makes any significant difference, especially if the car is moving and fresh cooling air is entering the engine bay.

 

If you leave your central heating boiler (your supercharger/inlet manifold in this case) on at full belt constantly and all of the valves to your radiators (your header tank) are open, even without a pump in operation they'll heat up at some point due to convection. Presumably even more so at the highest radiator (like the header tank).

[Mangham54]

I doubt very much the tank location makes any significant difference, especially if the car is moving and fresh cooling air is entering the engine bay.   If you leave your central heating boiler (your supercharger/inlet manifold in this case) on at full belt constantly and all of the valves to your radiators (your header tank) are open, even without a pump in operation they'll heat up at some point due to convection. Presumably even more so at the highest radiator (like the header tank).

You would think so, but the heating system in our house is very much passed its best. Run the boiler without the pump (no valves in our system) and all the upstairs radiators get hot. However the downstairs remaining stone cold. Flick the pump on and they heat up in seconds.

[NickB787]

my cc pump is at least 7 years old so will put an upgraded one on and see if it makes a difference to the temps, glad you sorted it finally, well done.

[alexb]

I've seen exactly the same thing on my car: just cruising along without using the SC much the intake temperature goes up to about 15C above ambient. That's the lower limit of the IAT. Searching the CobaltSS forum, as they have a lot of experience with this set up, it seems they experience the same. I assume it's caused by heat soak of the engine bay. The SC is not doing a lot when cruising. It's a pump, it doesn't compress. When it delivers against a pressure that's the same as before the SC, the air is not heated. And pressure is the same on both sides of the SC due to the bypass.

 

It is quite easy to calculate the energy removed by the laminovas. But you need to know the temperature of the coolant right before and after the laminovas and the flow of the coolant. That directly translates to a delta T for the air, assuming you know the boost.

[Arno]

The SC is not doing a lot when cruising. It's a pump, it doesn't compress.

 

 

True, the roots blower is only a positive displacement pump and not a compressor as such, but at the same time during light cruise the bypass valve is usually open and air is constanly being pumped through the SC (as it has a constant displacement) and then (re)circulated again back to the intake of the SC and AFAIK not going through the laminova's during that time.

 

All this time the air going around in the manifold and S/C is soaking up heat from the metal and probably some heat generated by the pumping process itself. (nothing is friction-less )

 

So i'm not too surprised that IAT's are going up above ambient at cruise.

 

It would probably already help if the bypass port on the manifold was after the laminova's, so the 'recycled' air gets cooled all the time as well.

 

A cooler matrix (perhaps an additional one) 'sandwiched' between the SC outlet and manifold (like on Honda SC installs) would perhaps help here:

 

 

Bye, Arno.

[alexb]

From the famous (but can't find it at the moment) video that shows an animation of the M62 at work, I seem to remember that recirculated air does pass the laminovas. But you're right, the more it circulates, the higher the temperature. Too bad you can't blow off a vacuum

 

 

[smiley]

From the famous (but can't find it at the moment) video that shows an animation of the M62 at work,

 

 

[Rosssco]

This one's better :

 

http://www.youtube.c...h?v=14MaYSMPc1c

[NickB787]

Leevx2.2 has one of these plates on his car, however I don't believe he has access to the IAT figures post install

[Exmantaa]

From the famous (but can't find it at the moment) video that shows an animation of the M62 at work, I seem to remember that recirculated air does pass the laminovas. But you're right, the more it circulates, the higher the temperature. Too bad you can't blow off a vacuum

 

 

 

As the animations show the SC air recirculation is pre-laminova and will heat up due to the hot parts there. But only a small volume is going past the cores to the engine, so the full Laminova capacity is available to cool this hot but small air volume... 

 

Recirculating all air through the cores will use more cooling capacity, so not sure if the portion of air used by the engine will then be cooler or hotter than above...  

But recirculating cooled air back through the SC should keep the charger itself cooler. Me think...  

 

Can we just conclude that for >300bhp we simply need more cooling capacity?

[CHILL Gone DUTCH]

Has anyone tried putting the Tmap/map sensor where it's shown in the video rather on the manifold I know this does not give true IAT but it would stop the retardation and extra fuel being injected Or would this be risking the engines a step to far ?

[Rosssco]

The video shows the set up on a LSJ engine, which uses a MAP (pre SC), TMAP (post SC) and MAF sensors (intake), IIRC...

 

Prob why the Yanks get much better calibration than us

[alexb]

 

From the famous (but can't find it at the moment) video that shows an animation of the M62 at work, I seem to remember that recirculated air does pass the laminovas. But you're right, the more it circulates, the higher the temperature. Too bad you can't blow off a vacuum

 

 

 

As the animations show the SC air recirculation is pre-laminova and will heat up due to the hot parts there. But only a small volume is going past the cores to the engine, so the full Laminova capacity is available to cool this hot but small air volume... 

 

Recirculating all air through the cores will use more cooling capacity, so not sure if the portion of air used by the engine will then be cooler or hotter than above...  

But recirculating cooled air back through the SC should keep the charger itself cooler. Me think...  

 

Can we just conclude that for >300bhp we simply need more cooling capacity?

 

 

Yes, recirc is pre-laminova, my mistake. And for 300+ HP and track work (large amount of on-boost driving followed by short off boost periods), you need more cooling capacity. The laminova design in the current manifold is just not up to handling that unless the coolant can be cooled to below ambient. So you need some other strategy. Ideas enough in this thread, but not a lot of solid data.  

[Exmantaa]

Yeah, ideas enough...

Anybody has a 3D printer for aluminium??

[Rosssco]

Yeah, ideas enough...

Anybody has a 3D printer for aluminium??

 

Printing a nice turbo exhaust manifold..

[NickB787]

does the manifold Need to be make of metal, what about plastic, how much psi will a plastic manifold take.

[Exmantaa]

Should be constructed pretty solid, as it holds the SC too...

[smiley]

Peter from obdtuner was pusing in air to generate about 318bhp with his rotrex. 

No idea on psi though.