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MGB New Dual SU's and Run-On

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BILLinPA

Freshman Member
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1978 MGB

I posted this last night, but not sure what happened to it...anyway...

I have new dual SU's and the correct manifold, but my ARO is not connected.
I do have some kind of nut where I believe it should go, but not the connector.

My question(s): could this be causing my run-on?
Do I need it with SU's?
if so, what connector should I pick up?

BILLinPA.
 
Which version SU's? Is your timing set correctly? is the distributor a 25D or the one that came with a '78 18GV engine?

With SU's you ~shouldn't~ need it. BUT(!) a lot depends on some other factors.
 
Did it do this before the carb change? A wise man on this forum says "It's always the last thing you touched." It is detonation of fuel without spark (dieseling). Things said to contribute are octane level, combustion chamber pressure (excess carbon), combustion chamber temperature, plug tip temperature, mixture, idle rpm. Old chevvies with 230/250 6 cyls were bad for it, but stopped quickly when you blipped the throttle after shutdown (mixture).
Bob
 
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