I'm currently gathering parts to supercharge an m42 engine for my 76 bmw e10

It was kind of a spur of the moment decision so I'm kinda researching as I go along


I have got an Eaton M62 which still has the merc pipes attached for £150 I also picked up a nissan gtir manifold which I plan to split and build a second half to suit my port spacing and injectors and engine flange etc.. From what I've been reading 30lb injectors are what people tend to use on boosted m42s usually from a Volvo so that will be my next thing to source along with a high pressure fuel pump and FPR

My main question at the moment is people who have done supercharged builds with eaton blowers.. What do you do with the bypass system?

For a bypass I used one from a MINI when I supercharged (M45) my MX5.

A few things to consider

Where is the throttle body going?
What are you going to do re the clutched pulley?
Belt tension and alignment are key to getting a reliable set up

Have a look on google, MX5Nutz for SC mx5's loads of relevant info there.

GKD may be worth a call as they have a super-charged offering for the M42:

http://www.gkdsportscars.com/supercharger-kit.html

We've just mapped a BMW 318 (1900cc) fitted with an M45 supercharger.

Have a look at our facebook page for pictures

www.facebook.com/baileyperformance

Thanks guys

Il check those photos now

I've had a look at the GKD kits before for a but of research obviously that's a smaller charger but the same principle applies.

I planned to incorporate the pipe work that's fitted to it already for the throttle body pretty much straight before the charger with the filter before that as space is kind of an issue. I haven't got the engine itself yet so il have a lot of measuring up to do for brackets but il more than likely aim to run a pulley in replacement for the viscous fan straight off the crank and use a later alignment to set it up. I'm aware tension is a major factor it was something I was still thinking about at this stage

Most people would either use the method that comes with the charger or just plum in a recirc valve between the plenum and pre SC. Vacuum comtrolled from behind the throttle butterfly.

when I finally get to converting mine I will be trying something different. I also have an M62 but will be using it on a 1.6 so it will be too large. Im going to spin it at the normal speeds to reach 1bar fast but have a waste gate with 1bar spring to regulate the boost.

this means that my boost curve should look like a turbo boost curve without the lag. It also means that I get more torque and avoid the peaky power curve you get from an SC set up.

we will have to se if it works but I cant see why not.

That is a good idea surely the flow rate of the waste gate should be taken into account as if it relives at the boost pressure it will actually open at boost pressure and relieve the pressure therefore you would loose the boost through it? I'm not sure on the sealing faces in a waste gate I'd imagine with it being air it would be a soft sealing face? (Metal sealing face would most likely have a leak rate at 0.9 bar under API527 if they run under relief valve standards which may not apply with it being on a car) I may be overthinking this totally but logically to me you will need to calculate the relief flow rate of the waste gate against the flow rate of the charger at set rpm to ensure you could hold that constant boost?

The flow rate does need to be considered to make sure it does keep up with the CFM. Do remember that it does not need to flow the CFM for the engine. It is branched off the main boost pipe and just leaks off as required.

The sealing surfaces I think are a seated metal vs metal. They are used to dealing with very hot gas so I doubt there are rubber gaskets hanging around.

From my understanding the wastegate is better in this situation than a normal dump valve (recirc or BOV) because it CAN hold boost. Remember these are normally used to control the boost on a turbo exhaust housing so it will hold boost until either it becomes more than a predetermined amount (normally governed by spring strength) or actuated via a control vacuum.

Look at the tial 70mm ones for an idea of their design capability.

By the way, I dont know if this would actually work but I am will to try it on my car when I get around to it.


[Edited on 30/10/14 by bi22le]

[Edited on 30/10/14 by bi22le]

You may be on to something now I think about it I was thinking more in terms of a bov actuated by vacuum as on many turbos it is relieved when the throttle is released similar to the idea of using the bypass I asked about in this thread I imagine

However there are solenoid actuated valves this may be an option? Especially if there was a way to run it through your management that would be awesome!
It would allow a lot of torque! Although I'd be looking into a decent intercooler and plenty of airflow to it as they generate a lot of heat compressing the air and that way would generate even more! Wouldn't want to detonate your motor with crazy hot intake temps!

quote:

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Originally posted by AdOz
You may be on to something now I think about it I was thinking more in terms of a bov actuated by vacuum as on many turbos it is relieved when the throttle is released similar to the idea of using the bypass I asked about in this thread I imagine

However there are solenoid actuated valves this may be an option? Especially if there was a way to run it through your management that would be awesome!
It would allow a lot of torque! Although I'd be looking into a decent intercooler and plenty of airflow to it as they generate a lot of heat compressing the air and that way would generate even more! Wouldn't want to detonate your motor with crazy hot intake temps!

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Interesting theory you have there I can wait to see it put into practice.

I came across this it would be good to see the car and what was achieved http://rennlist.com/forums/928-forum/662715-using-a-turbo-wastegate-in-a-supercharger-application.html

You have certainly got me thinking a lot deeper about what I'm doing now seeing if I can create a better system than the ones people are currently using (which lack of cooling is my main concern atm) and also the bypass

Picked my engine up so it's time to get to work!

Photos to follow

Are you going to implement any of my ideas?

At the minute I'm just going to be stripping it and figuring out positions and making the manifold

I'm still thinking about that it was a great idea but I dunno whether to take the plunge or not yet! You go first haha