Okay; - I'm a little lost here; - the riser that I was referring to is on the exhaust pipe, I believe it's on the driver's side in between the manifold and the exhaust pipe joint. The butterfly valve it actuates redirects hot exhaust back through the exhaust manifold back over the intake manifold. I believe if I read your response correctly, that the small coil and cover you're referring to is the choke actuator. It takes heat from this same cross-over in the intake, and if your heat riser is stuck it'll pull off your choke far too soon. Unless it doesn't work I'd leave it alone. They are next to impossible to replace now too, so don't throw it away. Also; - if the choke isn't working right or if that linkage from the choke coil is binding, then your secondaries won't come on right if at all. Check the diaphram on the front of the carb (if it's a stock quadrijet) and make sure it's still holding; otherwise your secondaries won't work right and you'll get some interesting bogging and flooding. These diaphrams have been known to fail, and they are replaceable.
Just read that you've got an Edelbrock on that motor; - ignore the part about the front diaphram, it doesn't apply, and chances are the choke is totally different now too. Now with that Edelbrock; - is it an even bore or spreadbore? What spacer plate did you use underneath it? From what I recall, (I'm sure others will chime in if I'm dead wrong) those BBB don't like Edelbrocks because they run out of capacity at higher RPM and don't move near enough air. With spacer plates or adapter plates, now you get into burned gaskets, warping issues, and the eventual vacuum leaks. You might want to start with that...
i would say. fill up 2 ice packs and get your engine to act up. put them on your intake and drive. see what happens. make sure the ice is wrapped in something that wont melt though
Yes, its an Edelbrock. It seemed to run much better with the Edelbrock (800cfm) than with the 600cfm Holley that was on it when I bought it and also better than the big 800 Rochester I tried. That one may have needed a rebuild though... Upper RPM does not seem to be an issue when the engine is cold so for a stock 430 it seems to be enough for now. Although the higher heat in the intake right near the carb mounting is strange, I am beginning to suspect fuel more and more. There is no heat riser on the exhaust so it may have been removed some time in the past. Not sure why the intake would be so hot right around the carb mounting. And you are correct, the choke is not hooked up to the intake mechanism. Have not used the choke here in Phoenix and am thinking of taking the choke parts off altogether. I believe the Edelbrock is square bore as I had to use the spacer/adaptor to mount it to the stock intake. I may try a fiber type spacer on top to rule out "boiling" fuel... Regarding gasket and vaccum leaks... Could it be that the leak opens up after warm up and is causing the accelerator issues? I hate to remove the intake until I get an aluminum replacement, but may have to...Trying to find a used B4B or other Edelbrock dual plane for under $150... Seems like when I bid on them they go over my price limit and when I miss the listing they sell for less! I missed by $6 on the last one...Go figure... With the problem coming on sooner now, after only 1-2 miles of driving, I am wondering if there is something getting stuck in the accelerator circuit? Could debris have gotten past the new filter and be lodging in the carb after a mile or two of driving and then settle back down after the car is stopped for an hour or so? Seems wierd. Seems as though it would not take so long for the debris to get stuck after start up since the motor sucks up so much fuel...Idle is still fine hot or cold. Thanks everyone for all of the input. If I had more time to actually dig into this I probably would not be bugging everyone about this so much! Just finished a three week stint of open to close shifts and travel to 5 states in 5 days!
