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MG Midget and Sprite Technical - variable boost control

A short while ago we had a discussion on 2 stage boost pressure operated by a switch

Well after much experimenting I have got mine working. I can run on normal boost say 6 PSI using a normal Metro actuator. Then at the flick of a switch a boost control is put into the feedback circuit hat restricts the pressure feedback and increases the boost to around 18 psi plus. This is adjustable by adjustment of a screw as displayed in the diagram.

Boy did I have some fun trying a whole host of tests to find a system that I am happy with

Robert (Bob) Midget Turbo

Bob,

Ive had an intresting idea for several years that goes hand in hand with your thoughts

Ive been thinking it would be cool to set up a variable boost control connected to the gear shifter

So 1st gear would be 2psi of boost, shift to secound and boost goes to 4 psi, third gear 8 psi, 4th gear would boost to 16 psi

The numbers are just an example, but I just always thought that would be a fun thing to try with a supercharger or turbo, infact a duel turbo where the jumps in boost would be like a leap frog

To pull something like that off you would need a high tech computer combined with a mega jolt / mega squirt system is my guess

Just something intersting ive kicked around, im not sure it would even be do-able, I guess if it were, everyone would be doing it

Prop
Prop

Congrats. Bob
It's always nice to get something working how you want it and this sort of thing soaks up the time
I'm having trouble blowing the pic up, but I think from what I can see that there are some clamps missing off your hoses - they all need to be clamped , It only takes one to come off and boost pressure will go skyhigh.
Again , well done ,looks the business
Willy
William Revit

Great idea... all it needs is a suitable switch in the cockpit with the appropriate labelling...

A
Anthony Cutler

Not sure how that would be a very desirable feature Prop but if you want to do it then fit a turbo and enjoy the experience.

Take your point Will but I would be very surprised if one of the clipless pipes were to blow off but I will keep a keen eye on them and if one does fly off then maximum boost would be the potential result! LOL

I have a switch of course Ant but as you say how should it be labelled??

Answers on a postcard to............
Robert (Bob) Midget Turbo

Bombs away
Onno Könemann

A switch a bit like this then ? I even fitted one that lights up when on high boost !

Never fitted clips in 3 years and not had one come off yet, that includes being flat out round Castle coombe but as Bob says its not the end of the world if it does...maybe the beginning!



Rob Newt

Overboost??


A
Anthony Cutler

Yeah
It all depends on how high the boost will go without the wastegate operating
We had a Falcon turbo in not long ago and the owner had tapped into the wastegate hose to fit a boost gauge (wrong spot anyway) It blew the gauge hose off,lost boost control, melted 4 pistons ,wrecked one bore and hammered the bigends out wrecking a couple of conrods in the process.All in about a kilometer
If you have propper clipless fittings - fine, not a problem, but just looking at your pic it was a bit difficult to tell what had been used, just thought I,d mention it as a precaution
Cheers Willy
William Revit

How about this?


B Young

Yes... with the potential re-arrangement of engine internals, 'warp drive' seems entirely appropriate ;)

A
Anthony Cutler

Scotty, can you give me any more power?
Aye Captain, I'll have Robert flip the switch! ;-)
B Young

"ludicrous power" ...Obscure "Space Balls" reference
Trevor Jessie

I don't know, I've looked all over my car but I can't find this "boost control" that you are referring to. Maybe some DPO modified your car at some point?


Norm "what were we talking about?" Kerr

Norm Kerr

I rather like the star trek references

Perhaps "warp 9"

Or perhaps better still the "Scotty" switch!

Is that a joke Norm? am I a DPO?
Robert (Bob) Midget Turbo

Nerd allert!
Warp drive would be more appropriate
Or if you like that other syfy show " hyper drive"
How ever I think I'll rather drive around with a red H on my head
Onno Könemann

So you are in favour of a "Rimmer" button then Onno :)
Robert (Bob) Midget Turbo

:)
Onno Könemann

This thread was discussed between 31/07/2011 and 02/08/2011

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