Pi22 yUP - The next phase, supercharging

[RB2]

Managed a little shed time today, so I've continued with dismantling the other engine. I am going to need to get some boxes to organise the bits and clear the work bench. Also had a visit from the dog.

There couldnt have been much flow through the head

 

[RB2]

So now it's a bare block.. time to work out what's next

 

[RB2]

Giving the block a closer inspection and I can't see any evidence of cracking or scoring on the bores, so I think this will be OK to continue with. Whilst I work out the pistons to use, I've brought the block outside for a bit of a wire brush, degrease and derust.

 

[RB2]

After the rust treatment and a bit of a wipe down.

And a coat of black enamel.

A fine Sunday job

 

[RB2]

Lots of clean looking bits now. I've reached out to metric mechanics, so hopefully I'll have a plan on the next bit shortly..

 

[RB2]

Progress has slowed as I've been using the car. I am still compiling bits for the sc.

I've sourced some spacers to let me use standard injectors oppose to the air shrouds

I've sorted the heater resistor so i now have 4 settings. Dogs hung out whilst i did that.

Decided to change the rocker today. A red one adds at least 5hp.

It was also treated to some new oil, the sump plug parted, so It was an easy out to the rescue.

 

[RB2]

So i am back onto the supercharger. I've started ordering up some of the pipework needed and the bypass valve.

The intake pipe work will look something like this and the two left are going to be charge to the cooler and charge from the cooler..

Part of the puzzle is the bypass valve. Now I had in my head that is would be open and by pass the charger when at idle and no vacuum. I've bought a bypass valve for a mini to use as its a little self contained unit including its own vacuum line. The puzzle is its closed unless it sees vacuum?!?!

I was planning on cutting into the charged side manifold here..... (vacuum inlet is on the noncharged side)

And then tee into the intake side over here... albeit with a smaller tee and a bit more refinement.

If anyone know what they're doing with supercharger recirc valves, please jump in before I start cutting holes. Potentially the pick up for the vacuum is on the wrong side going by the hyde schematic below, but when used in the mini configuration, the valve backs onto the charge pipe I believe.

Also thanks very much to IainP for thr speeduino board and ecu. So far endless hours of reading.

 

[IainP]

With supercharges the bypass valve is usually used to bypass the charger completely at idle Richie. So normally closed, but opened with vacuum, idle and steady state, when the charger is not really needed. It’ll close as soon as the throttle depressed, sending the airflow through the charger completely. Also means when the throttle closes at high revs the engine doesn’t get boost, or surge, when the car is trying to slow down. I think some of the Eatons have it built into the rear casing.

 

[RB2]

With supercharges the bypass valve is usually used to bypass the charger completely at idle Richie. So normally closed, but opened with vacuum, idle and steady state, when the charger is not really needed. It’ll close as soon as the throttle depressed, sending the airflow through the charger completely. Also means when the throttle closes at high revs the engine doesn’t get boost, or surge, when the car is trying to slow down. I think some of the Eatons have it built into the rear casing.

This one came from an SLK which looks to have had an electronic bypass. Decided to try a little experiment and it does function as i expected. Open when the pedal is lifted and closed when pressed.

 

[RB2]

So, as the recirc seems to be for a pressure relief I've gone with a smaller tee, over something the full inlet size and after this morning experiment, made some holes on the boost side of the inlet for the valve.

I'll get some black gasket rtv on the threads and some Nordlok washers and the recirc valve should be secured and boost tight.

 

[RB2]

I decided there is only so much i could do on the bench. So, set about the car. It's just a trial fit to check clearances, as i need to sort out some coolant pipe routing.... I think its going to need a bulge

 

[Duncodin]

I decided there is only so much i could do on the bench. So, set about the car. It's just a trial fit to check clearances, as i need to sort out some coolant pipe routing.... I think its going to need a bulge

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Side view looks like the pully is way out in front of the engine. I assume it's driven off the crank. Is there another pully bolted to the crank? How does the belt avoid the fan?

 

[RB2]

Yep, the pulley on the pwsp gets doubled up, with a small spacer between. There is another plate to add between the sc and alternator that has the tensioner for the belt. I'll be ditching the viscos fan in favour of an electric unit which will be a bit better on space. The space will be needed more for the top hose of the radiator clearing the belt.

Here is a better photos of the pulley for reference, I've still to fit the doubler.

 

[Duncodin]

Actually more room there than I thought. The pully is further over to the left than I remember.

 

[RB2]

Well, the clearance issue has been addressed. Mad max would be proud, purists not so much. Now to find a cap for the hole...

 

[Duncodin]

Y'know - I was going to mention MadMax

You need to raise it up a bit and add a clutch to the pully with a big switch on the centre console