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-   -   Project issues. (https://www.nopistons.com/1st-generation-specific-16/project-issues-59489/)

One320B 05-21-2006 11:52 PM

Ok, simply put, I know the 650 is too much on stock ports..this was only to get the car running under it's own power to move it around while we did the body work...



Here's the issue #1. The car will start, but as soon as it starts, it starts to pick up like crazy...revving high..really high. After getting the car turned off (issue #2) we checked everything, found one vac hose open, capped it..tightened the adjustment for idle..adjusted the mixture screws...started up again. This time it revved slower, but still went to about 4K, putting our hand over the carb dropped it to 2k..but that doesn't solve our issue. My question is, would a 650 carb on a stock port make it do this? There are no vac leaks that we can find, aside from maybe the manifold isn't perfectly tight, but it should be..new gasket, new orings, etc..



Any thoughts on this? I'm an FC EFI guy..not an FB Carb guy..so any thoughts are welcome!



Issue #2. Car won't shut off by the switch. I can take the key out and it still runs. The same issue came up on a buddy of mine's FB when we put the motor in it, and we found it was a crossed wire on the alt, but i dont think that is this issue.



I'm putting up some pics of the carb and alt, let me know if you see something odd here. I didn't take the original stuff off, so i dont recall what all the wires go to, etc.. i know most are just for the solenoids which i'm not using now...i figured this would all be simple. Oh well. Thanks guys/girls!

One320B 05-21-2006 11:54 PM

We also have the smallest jets in the carb. We're thinking that either the carb needs a rebuild (even though its basically brand new), the butterflies are sticking open, something is backwards, who knows.. I'm going to call around tomorrow to some carb tuners i know to see what they think...

j9fd3s 05-23-2006 10:26 AM

if its idling high, its getting too much air, and fuel. prolly too much air, you're looking for vacuum leaks, and stuff but it might just be that the carb is too big

One320B 05-23-2006 01:17 PM

Well I actually did some research and found that back in the 80s Racing beat offered the 650 for stock port 12As.... and I managed to find some stuff where guys were running them, so I know it can be done and that the carb isn't too big to be able to run. It may have to idle at around 2K...but I'm fine w/ that...as long as its not 4K.



Also, the carb has drag floats on it, so I'll have to swap them out. My buddy is rebuilding the carb this week for me just because he thinks something is up w/ it....



We'll see... I'll run some RTV around the intake as well.. maybe spray some starter fluid, lol...see if i find a leak..


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