British Leyland

[pete376403]

Assuming that theres a turbo under the intercooler, how does it get on with blowing through the SU carb?

I did a Mini turbo 20 odd years ago for a speedway saloon, that used a blow-thru 45DCOE. Sealed bearings for the butterfly spindle and plastic DellOrto floats 'cos the brass Weber ones collapsed under boost pressure and sank. IHI turbo, no intercooler
1440 (Datsun 1200 pistons, S rods on an offset ground crank) 649 cam and 10PSI boost was worth around 130HP at the wheels. Used to eat driveshaft joints until the owner got hardie spicers.

Would have been an absolute hoot in a road car.

[jonbuoy]

Assuming that theres a turbo under the intercooler, how does it get on with blowing through the SU carb?

I did a Mini turbo 20 odd years ago for a speedway saloon, that used a blow-thru 45DCOE. Sealed bearings for the butterfly spindle and plastic DellOrto floats 'cos the brass Weber ones collapsed under boost pressure and sank. IHI turbo, no intercooler
1440 (Datsun 1200 pistons, S rods on an offset ground crank) 649 cam and 10PSI boost was worth around 130HP at the wheels. Used to eat driveshaft joints until the owner got hardie spicers.

Would have been an absolute hoot in a road car.

MG Metro Turbo was a blow through HIF44, didn´t run huge amounts of boost though. The supercharger setup on the MGB I have is suck through on an HS6.

[Indiana_Jones]

MG Metro Turbo was a blow through HIF44, didn´t run huge amounts of boost though. The supercharger setup on the MGB I have is suck through on an HS6.

Got any pics of that set up?

Single HS6? Rape the mpg?

....as my current set up is a 1800 B-series with single HS6

-Indy

[ducatilover]

Doing a blow through set up isn't hard on carbs.
My 600 is getting a T25 blow through set up this year
CV carbs are nice to rune too.

A turbo mini would be a laugh.

[Fast Eddie]

yea theres a pic of my old turbo 550cc honda cbx on my page thing.. simple enough to blow thru carb. Tuning is the hard part

[jonbuoy]

Got any pics of that set up?

Single HS6? Rape the mpg?

....as my current set up is a 1800 B-series with single HS6

-Indy

I'll put some pictures up tonight working on the car for the last few weeks, the guy who "rebuilt" the motor before me didn't bother changing piston rings

[Indiana_Jones]

Awesome

This thread needs more British cage sweetness

-Indy

[Bender]

Oh all right then.

Not exactly BL, but if you're talking class British cars, how could you go past this.

[Indiana_Jones]

That I like

-Indy

[ducatilover]

Tuning is the hard part

If you're a n00b

[jonbuoy]

First test run of the amateur rebuild (me!) that had to be done after the "proffesionall" rebuilder thought a coat of paint and a new oil pump was a "re-build" . If you want a job done right blah blah....

[Indiana_Jones]

Looking nice

Damn I'll never have the space to get a super charger like that on my engine, not enough space!

-Indy

[ducatilover]

First test run of the amateur rebuild (me!) that had to be done after the "proffesionall" rebuilder thought a coat of paint and a new oil pump was a "re-build" . If you want a job done right blah blah....

How well does she go with that draw through set up? One sexy look MGB for sure!

[pete376403]

yea theres a pic of my old turbo 550cc honda cbx on my page thing.. simple enough to blow thru carb. Tuning is the hard part

Well the thing with blowing through the carb is, whatever boost pressure the carb is seeing in the throat, it needs to see the same pressure in the float bowl, or else the fuel will not be drawn through the jets. If the pressures aren't the same (ie higher in the venturi than in the bowl), fuel will be pushed back up the jets (carb 101 - atmospheric air pressure in the float bowl is higher than the pressure in the venturi, that pushes fuel through the jets)

The mini I turbo'ed was running 10PSI boost, I made a boost controlled fuel regulator valve, and used Triumph 2.5PI fuel pump (Lucas - same motor as windscreen wipers) this in the days when it was not possible to buy this sort of stuff off the shelf.

With the Weber carb the float chamber vent is on the front so it was easy to build a box to attach the hose from the compressor that cover the vent and the venturis. (Dellortos have the float chamber vent on top of the carb - the car owner tried a dellorto once. Worked really well until boost came on, pressure forced fuel out the vent and all over the exhaust manifold. Took a while to put the fire out.)

Tuning (ie jetting) was relatively straight forward, about an hours worth of dyno time. Water injection was added later, again home made - windscreen washer bottle and pump, pressure switch and a brass jet in the compressor intake.

The car was so successful in an up-to-2.3 litre class that turbos were eventually banned.

[jonbuoy]

How well does she go with that draw through set up? One sexy look MGB for sure!

It goes well mate, very torquey. Got a special grind cam and a head ported by Peter Burgess specially for the supercharger. On Peters rolling road it made only a little less HP than a stock MGB V8. Happy ish with the motor but wish I had got Peter to do the whole lump. I'm going to run this bottom end for a couple of years and then get Peter to build up a stronger one and put a smaller pulley to up the boost a bit.