Hello: I am getting ready to install a 4v intake manifold on my '65 300 motor. What is the best carburetor to use with this stock manifold? I appreciate your input. Rickli :3gears:
Rick... OEM was the Carter AFB of about 550 CFM. You can purchase essentially the same carb brand new. Edlebrock (which purchased the license to build Carters) has a Performer or as a Carter AFB. I'd opt for the electric choke. JMC
John, Thank you for the reply. I wasn't sure which might be better, a Q Jet or a Performer carb because I think the factory manifold is a spread bore and would I need an adapter for a square bore Edelbrock carb. Either way i'm going with the electric choke. Thanks Rick
Hey, if you do by that Edlebrock Performer carb and you have the '65 cast iron intake manifold, you'll also need a 1" spacer. Otherwise the throttle won't close all of the way (it hits the intake). I have this setup & ran into that problem. Looks like I could have ground down the throttle linkage on the carb to avoid the collision but I just bought a spacer for $30 instead. Not sure if the '64 aluminum intake will have this problem.
Whoa...All 300 four barrel intake manifolds are square bore. The spreadbores didn't come out until later! Make sure you have a 300 intake manifold. I'm not sure there was ever a spreadbore 300/340 intake--didn't all 340-4V engines use the Carter as well? Aaron
Mine came with a Carter. Replaced it with an Edelbrock Performer 600. Had to use a spacer, a generic air cleaner, refit a banjo fuel connector, and re-route the fuel line. Also, had to grind down a square-ish casting boss directly under the carb throttle lever. Just sliced it off with a Dremel grinder. With the Edelbrock, electric choke, and electric fuel pump, I can start my car in one of two turns even after sitting for weeks. Almost as easy as FI.
Harry, What electric fuel pump did you use and how did you set it up? That's an upgrade that I need with this stinky oxiginated CA gas we have. The stuff evaporates right out of the carb in no time. Takes at least 10 seconds of turn over to light off after just a couple of days sitting. Cheers, JMC
Just bought a low pressure (think about 4-6 psi) generic AC Delco electric fuel pump from a local auto shop. Cost about $60. Screwed it into the driver side frame just ahead of the rear axle and used rubber fuel hose to connect it to the tank. A show judge would never see it. The factory pump stayed as is. I only run the electric pump from a toggle switch under the dash when starting the car after it has been sitting more than a few hours. After starting, I turn it off, as it is very loud, even with plenty of rubber insulation. I understand that the loud thumping is normal. You want a low pressure model, as the racing ones may not allow the factory pump to "pull through" them, while mine does. When I get around to replacing the tank fuel sensor, I think I will buy a "fuel return line" model and run another hard line to (a slightly newer) mechanical fuel pump. I understand that is the ultimate fix for vapor lock and other fuel supply issues.
Harry, The return fuel line setup would be what was offered on the a/c-equipped Skylarks of our vintage, I think. I'm not sure how all that works, but if it improves drivability, I'm in there. This setup requires a different mech pump, too? Thanks for the fuel pump info. Cheers, JMC
John, Yes, I would have to buy a different mechanical fuel pump for the extra line. About 5 years ago, I did the "car project from Hell", which was to install factory a/c from a junked 1966 Buick Special. What a challenge, especially the dash modifications....but nobody would ever know that the car was originally non-a/c.
There is a factory '65 300 4bbl Carter AFB in the parts for sale section for $50. It will bolt onto your intake perfect and everything hook up like it came on the car. I highly recommend the factory carb--they run perfect since they were designed for the engine. They are small, but so is the engine. You won't be limited by the small CFM unless you have a highly modified engine and want to turn over 5500 rpm.
jinman and Yellowlark I'm about to embark on this same conversion in my '66 Skylark. I have the intake manifold (all cleaned and painted), and I got the Edelbrock 600 cfm for Xmas. I was just playing around and noticed the linkage problem. I'll pick up a spacer tomorrow. What other problems did you run into? I have an ST300 - did the kickdown hook up correctly? Any worries about jetting? Were there hood clearance problems with the aftermarket air cleaner and spacer? Yellowlark - you mention you had to "refit a banjo fuel connector" - what does that mean? Seems to me I could just extend the rubber line from the fuel pump w/o problems. Are you happy with the results? I installed true duals and just put a new cam in, so I'm hoping to see some gains with this conversion. I would *love* pictures and any other feedback before I embark on this conversion. Thanks!
The Performer's fuel inlet came straight out from the carb and there was a clearance issue with the rubber fuel line being seriously bent. Had to buy a replacement brass fuel inlet that looks like a banjo and provides a 90 degree angle. Faced the nipple at about a 8 o'clock angle, and that solved the problem. The banjo fitting is a common carb accessory I picked up at a speed store. I am happy with the results. The Performer is reliable and well-designed. Your original air cleaner will not fit the carb. A generic Edelbrock 14" model will fit and there is no hood clearance issue with a 3" filter. I bought a K&N filter element. Shortly after installing that carb, I replaced my ST300 with a 2004R. So, while I had to do some fabrication on the carb linkage, I don't recall if it was due to the carb or the trans switch.
Thanks YellowLark - anything you can recall or any pictures you have for getting the Kickdown linkage to work would be greatly helpful. I finished the installation today - got the car running fine but there is no provision for the Switch Pitch - on the old 2bbl there were 2 posts that both moved back - on this carb, there is only one, and my attempts to fabricate something don't seem to allow the same range of movement I had before. I would love to get this working so if you figured it out, it would be extremely helpful. Thanks!
Upgrading 300 motor Good Evening! I am in the process of upgrading my 300. Its on a 65 Skylark Conv. Does anyone know of any 4 bbl intakes available for purchase? And, what would be the best carb to match up with this set up.
Better plan on spending some bucks. A 1965 Buick 300 4bbl manifold just sold on eBay for $365 amidst heavy bidding. The most popular and easiest fitting carbs are the Edelbrock/Carter 500 and 600 cfm Performers. The 500 cfm model is recommended for otherwise stock engines.
