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Discussion Starter #1 (Edited)
So I got my 79 GTV back from having underside/suspension work done.

First time ever I got to drive it any reasonable distance. Up till now it was just around the block.

Having sorted the starting and general running issues, this 10km jaunt revealed the car's significant lack of power and response.
With a reluctance to rev and respond to throttle input I am thinking that the distributor may not be advancing (ie weights seized)
Is this a common thing?
Static timing has been checked ok..I dont have a timing light to check otherwise.
Was a 30c degree day and car did not overheat.. Car idles very well, but again a very dead throttle even just trying to rev at a standstill.
Engine is rock solid with great compression and no oil burning.
Car has Carbs not injected.. The Dellorto Carbs fitted not ideal from later model but good condition
I have a well sorted 79 sedan that is very different and a joy.. So its not just old design v modern expectation..
Thoughts please
 

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When I bought my Alfetta - I felt the same. It was responsive, but strangled at anything over 2000rpm and anything over 1/4 throttle. Turned out to be an almost completely clogged center resonator in the exhaust.
 

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When I bought my Alfetta - I felt the same. It was responsive, but strangled at anything over 2000rpm and anything over 1/4 throttle. Turned out to be an almost completely clogged center resonator in the exhaust.
Good work finding that :wink2:
 

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Is it Marelliplex? For some reason those distributors seemed to have the advance stick more than others. Without advance the car will feel really dead. You wait to build speed.
Not that it would likely go bad in the shop, but a compression test will tell you how the combustion chamber is doing.
Andrew
 

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Good work finding that :wink2:
They make backpressure gauges you can hook up to a port/nipple on the exhaust, or the poor mans easy method is to unbolt the exhaust after the down pipe and wedge it apart a little, then go for a drive.
 

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Richard Jemison
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Good Call !

I'll try that one. That's the second Resonator in your basic Alfa three piece system?
 

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Hi ACT116

Accelerator pump jets not squirting on 1 or 2 or 3 of 4 of them blocked.
That will give you no low down response.
Just a thought
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Turned out to be an almost completely clogged center resonator in the exhaust.
Simple test for this really (assuming an intake manifold vacuum source is available). Just hook up a vacuum gauge and crack open the throttle. If the vacuum drops then comes back up, all is normal. If the vacuum drops and stays down, suspect a blocked exhaust.
 

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My 1976 Alfetta GT was supposed to have Dellorto DHLA40H, but it now has DHLA40. The 'F' and later are smog carburettors so have a very lean progression phase, and require a totally different ignition advance, this cannot be 'jetted out' . If you drive at constant speed (not in the progression phase of the throttle), everything will seem fine, plenty of power etc until you try to 'pump' the accelerator. Now that I have a matching distributor and carburettor (Giulia 1969 spec) it runs great. But then again it might just be the car wanted attention, it being an Alfa and all. First thing is check the timing, and then the spray pattern on the pump jets.
 
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