Has anybody performed the modification to there carby that vizard states in his How to tune an a series engine book? Just wanting some feedback on what you guys think of the mods.

Cheers, Tom

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If its yours, customize it !

Need some more info.
Which carby and which modification/modifications?

Mods to throttle shaft are OK, but don't modify the jet bridge as he shows... people here have had dramas with that mod.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Sorry. He has a part in his book about increasing flow through su carbs. Eg reducing spindle and butterfly thickness. Cutting off butterfly screws obstructing bore of throttle body.

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If its yours, customize it !

I did the throttle shaft & screw mods many years ago (well before Vizard wrote it up)- I think for a road car it's a bit of a waste of time. Most of this stuff (Clive Trickey started it) was to get a bit of flow through an HS2 carby.
Get a bigger carby... better idea these days.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Yeah I'm pretty much just doing it for a bit of fun more than anything. Just was wondering if by cutting half of the spindle away and filing the otherside leaving more obstruction on one side of the butterfly than the other would create turbulence that could effect the Venturi effect in the carb. Hope this makes some sense haha. It does in my head.

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If its yours, customize it !

Sorry about the slight thread hack, but on the topic of carby mods, would it be worth attacking these burrs with a file? Its a HIF44

I did the flow mods to my twin 1.5"s and they worked well. Recently one of them was put onto a standard 1275 in a clubman, replacing a worn 1.5 - the owner was very very happy

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Don't suppose you have any pictures? I was a bit hesitant to make the spindle so thin where the butterfly bolts up to it.

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If its yours, customize it !

no, but I do now....

here's the shaft, I reckon every little bit helps, but I didn't do a lot, just ground flats on them - I loctite the screws in, can't actually get them out again without wrecking the heads



here's where I did most of the work, get rid of the ridges, open out the square area around where the piston comes down





don't touch this bit!!!

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did I tell you that I won a trophy?

Awesome. I'm hoping to get a bit more done on the weekend. In between rebuilding me gearbox and re ringing my engine. To many things going on.

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If its yours, customize it !