Pi22 yUP - The next phase, supercharging

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.
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There couldnt have been much flow through the head
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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.

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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
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I've sorted the heater resistor so i now have 4 settings. Dogs hung out whilst i did that.
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Decided to change the rocker today. A red one adds at least 5hp.

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

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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..

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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?!?!

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

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

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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.

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

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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.
 
IainP said:
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.
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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.

 
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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.


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

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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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RB2 said:
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?
 
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.
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Oh man, I’m gutted by this! I had strongly considered this exact supercharger build, even to the point where I sourced a supercharger at the local pick and pull. To find out it doesn’t fit :( I’m not prepared to cut a hole in the hood of the car.
 
greisinb said:
Oh man, I’m gutted by this! I had strongly considered this exact supercharger build, even to the point where I sourced a supercharger at the local pick and pull. To find out it doesn’t fit :( I’m not prepared to cut a hole in the hood of the car.
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There has been another few little bits about the kit that's made me question it. Daft things like the pulley spacer not being correct, bolts being the wrong length, belt too short etc. They were quick to make a spacer to the correct length and ship foc from germany when I enquired about it, so i can't fault them on after sales. The bonnet bulge was a bit of an over sight haha and not listed on their page, but for me, this car is just a bit of fun. It was far from concourse, so the bonnet was fair game. If it was a nice example I would have been more reluctant. The up side is i should hear it.

I have been slow on progress with it lately. I have sorted the heater pipes for the throttle body which has let me get the manifold in. The 24mm spacer sorted the back to back pulley. I bought a 1275 belt as the kit supplied one was way too short. Tbh it could be done with another 10mm but it's on. I need to move the top radiator still and take out the viscus fan. I plan to reroute the loom as well to make it more accessible.

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I am still looking at a suitable bulge. To cover the hole. Daft fiberglass parts seem to be very expensive for what they are.
 
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My immediate thought for the bulge is a 3d printed part. But that’s my initial thought for most things.
 
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That might be a good idea that, there is one in work that they use for prototyping parts. Might be worth an investigation.
 
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