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I have been working on my Opel for a few months now, and finally got it on the road. At this point, I am running the 32/36 weber, new tune up parts. including plugs and wires. I have played with the timing quite a bit. and I can not seem to fix this problem. When running, I seem to start loosing power at around 4,000 RPMs. However If I continue, when I get to 4,300 RPM, al of the sudden the power drops to 0. That RPM number does not seem to change with any timeing adjust ments. I even get the same effect if I remove the vacuume advance hoses. I have checked the advance by sucking on the hose. I see it move the advance. Any suggestions? Also, as I have never drive any other opels, I'm not sure if the HP is lacking through the entire powerband or not. A list of stock 0-60 times would be a great help to know if I am getting everything out of the car that I can in it's stock form.

Thanks.
 

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Two items jump right out on this one. First is a possible vacuum leak, most likely at the brake booster. Second and Maybe I'm the only one to have seen this one but a bad rotor or cap can act like that too. HTH
 

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Have you checked the centrifugal advance? disconnect the vacuum advance, time the engine with the marks aligned then increase the speed. You should see the timing mark move toward the advanced side. Also check the dwell to make sure it isn't changing with speed. A good distributor should allow the engine to run through it's full speed range with the dwell changing less than 3 degrees. If you get significant dwell changes with speed, the distributor is worn out.
 

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I had a similar problem and it turned out to be the coil breaking down. It started missing and lost power at higher rpm's. pulled a coil off one of the others and she started running better.
 

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Über Genius
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I had the exact problem with 2 different problems causing it. The first time it was the condensor....The car would run great as long as I didn't get past @3800 RPM.

The second time it was the float. The needle valve was weak which caused it to leak a little. But at the higher RPM's it was just enough extra pressure from the fuel pump that it overflowed and flooded out. This happened at around 4000 RPM just like yours. But if I idled down, it would smooth out.

The condensor thing would take a few minutes to cool down before the car would even start.

A coil will also do this though.
 

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Discussion Starter · #6 ·
I've done a couple of these. but I think that main cause is a vacuume leak. I've stoped most of it. But I think I've got a bit of a leak under the heat sheild. I've been able to steadily increase the power in the car from when I first drove her on the road. But I'm still not able to hit 60 in under 25 seconds. So I've still got some work to do. But for a 32 year old car I don't give her too hard of a time. Thank you for your suggestions.
 
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