Supercharging a 16V?

[tim leech]

Is it possible to do it, purely just a question, im no mechanic, one of the lads at work has done his VR6 Corrado and it wasnt that difficult and the effects are astounding (100bhp more), he substituted the A/C pump for the superchager, my 16v has A/C but the pump is removed and it made me think if its possible. Only thing is the pump is on the other side of the engine to the air intake.

I imagine the Mi engine would explode?

[jeremy]

The 16 valve was designed to go like a turbo - without one and all its problems like lag.

You'd have to lower the compression ratio to prevent damage from pre-ignition - turbo's of the 80's typically ran something like 7 or 8 to 1. Sometimes this can be done using a thick gasket - I wonder if one of the diesel thick ones would fit and do the job - time for some investigation and calculation.

As for the rest of it - I don't think it would burst - have a look at Puma - the suggestion there is that loads can be done without touching the bottom end.

http://www.pumaracing.co.uk/

Of course the chassis would need some attention as I'd have thought it was somewhere near its limit with 160 BHP.

[Way2go]

Does this correlation with turbocharging apply though Jeremy? Tim is asking about supercharging and that has a direct coupling to the engine and so is more directly engine rpm linked on that basis.
Another question is that with a light car like the BX, can you put the power down if you achieve the increase?

[tim leech]

The 16v has excellent traction for what it is, its just a case of feeding the power in gently as with all cars.

[mat_fenwick]

What about converting the engine to run on LPG (which has an octane rating of about 114 RON if I remember correctly) so on LPG you could safely raise the compression ratio without detonation. Use LPG injection so no inefficient mixer ring, and run more ignition advance when on LPG (need a mappable ECU with switchable ignition maps) to get the most from the LPG system
Use a supercharger that has a clutch (Mad Max style), I think some Merc have this arrangement to cut the supercharger at idle. That way, on petol the engine will run happily on the original compression ratio, but switch over to gas and you'll have more performance and half price fuel...why isn't everyone doing it???

[tim leech]

Good point, the only thing is the conversion itself would cost more than the supercharger installation, plus I do about 1000 miles a year in my 16v so wouldnt pay for itself in that way.

[jeremy]

One of the problems with a supercharger is that it takes loads of power to drive it - which means a substantial and robust drive system - hence the 3 in wide toothed belts you see on dragsters - so an adequate drive would have to be provided and as the grooved auxilliary belt is quite prone to slip when simply driving an alternator I doubt if it would be adequate. As you know there isn't a great deal of spare room round the cambelt end of the engine.

The problems of detonation would of course be the same as for a turbocharger (perhaps worse as it would boost at lower revs)

What comes to mind is the 2.0 CT engine as fitted to the Xantia Activa which is a turbocharged 8 valve producing enormous torque over a very wide range. After all if it can propel something as heavy as a Xantia just think what it would do with 1/4 tonne less in a BX.

[docchevron]

Is it possible? Yes.
Is it worth while? Well, thats debatable.
Going to the Moon was feasable, but was it really a good idea?

As a technical excercise it could be interesting, but longevity of the engine would no doubt suffer if used to it's new potential all the time.

You also have to think about clutch, transmission, driveshafts and brakes etc etc.

After all, a T16 isn't just an MI16 with a turbo lobbed on.

A 2.0CT engine is indeed rather good, but thirsty with it..

In my humble opinion a well sorted D6C is plenty quick enough without bolting life limiting bollox onto it.

[citroen7]

this was mentioned to me by the chap i bought my last mk1 off.He had a 16v that had an engine fire in the yard and he was going to put the 2.0l engine from a xantia activa, said it was a straight swop!
i will be visiting north wales at easter so will call and see if he is still around and did he do the conversion.

[docchevron]

Physically, yes, it's a straight swop, as is pretty much any XU into any other XU engined car.

[DavidRutherford]

one of the lads at work has done his VR6 Corrado and it wasnt that difficult and the effects are astounding (100bhp more),

Is that measured with before and after dyno runs, or just a guess? I cannot imagine that a simple "bolt on" supercharger would increase the output hp by anywhere near that much.

[docchevron]

Even if he is getting an extra 100hp, how long will it be before he's getting a close view of his conrods?

[kermit the frog]

I agree with the doc on the looking at conrods theory
without major internal modifications to an engine that was designed to be normally aspirated you are seriously compromising it's internal strength.

I know from very first hand experience what turning up the boost on an un modified engine does

My Nissan SKYLINE detonated five pistons out of six when i ran 1.8 bar boost through it when the standard boost is 0.8 bar and it cost me a fortune to fix.

But if you have to do it limit the boost to 0.3 bar and you will still feel the difference
And you probably won't need to lower the compression ratio it's called low boost assisted

Unfortunately as was also said superchargers do take power before they give power.

However the link to top fuel dragsters is a little tenuous as they run nitro methane and very high compression and use approx 5 to 7 gallons of NM to cover 1360 feet in under four and a half seconds and produce in excess of 5000 horse power

Regards Kermit

[mat_fenwick]

However the link to top fuel dragsters is a little tenuous as they run nitro methane and very high compression and use approx 5 to 7 gallons of NM to cover 1360 feet in under four and a half seconds and produce in excess of 5000 horse power

Regards Kermit

I've heard it said (don't know how true it is!) that the supercharger on a top fuel car takes something in the region of 1000(!) horsepower to simply drive it

[charlotte001]

I have had experience in Turbo charging a normally aspirated car but not Supercharging. The one I have experience on was the Volvo 760 GLE with the PRV engine (peugeot, Renault, Volvo) V6 2.8 to do this the internals had to be replaced with stronger conrods/pistons/ Crank shaft balanced (Not cheap) Gasket to lower compression ratio and the Valves modified. Ok we bolted two Garrett Turbos to the beast (not recomended) The hardest part was getting the Mounts for the Turbo's to fit to the exhauts. It's not a thing to take lightly or a Saturday pop

Give Turbo Technics or Courtney Sport in north walsham a buzz I don't know if there's a turbo/supercharge expert over your kneck of the woods I'm guessing there is there are a few in Norfolk and Suffolk who really know their stuff

Charlotte001