Anyone know any current part#’s to a good vacuum can for a HEI distributor on my 68 400? I seen some old articles around the web recommend a Echlin VC 1810 because it activates at a fairly low vacuum to go with a decent cam but it is no longer offered and am having trouble finding a superseded part#?
Car is idling hot and has no vacuum advance hooked up and would like to give that a shot hooked to manifold vacuum? Has a Cold Case Rad, Flowkooler Pump, and heavy duty 19” Flex Fan, and has no issues while moving, but stop for very long at stop lights etc, she starts climbing quick?
Sorry, I can't help you with a part number but I agree with your assessment that you may be able to reduce idle heat with more timing advance. How many inches of vacuum are you pulling at idle? My HEI had a 517 18 can on it and my 428's 9" of vacuum would advance it. Is your vacuum at idle so low it wont pull the canister?
What about adding some initial advance?
One problem with having a can that adds advance at low too low a vacuum is part throttle power detonation. Mine was not detonating at WOT pulls but was at partial throttle pulls, up hill or power pulls when the throttle was not fully opened. I tested that can, it started to pull at 5 inches and was full application at 11 inches. Have a different one on now. The 517 is the last three numbers of the gm part number, sorry I don't know what the rest of the number is. It may have been from a 1975 455 but I'm not sure.
Hey guys, sorry for the delayed response, things have been crazy, been meaning to get on here, but anyways the car did not have a vacuum can on it, it’s a HEI and was recurved and all set on a dyno before I brought it home, they ended up settling on 33 1/2 degrees total, which seemed kinda weird🤷🏼♂️, but I actually don’t even own a timing light, yet, guessing it’s right around 13 degrees initial, seems like everything I read on HEI’s is that they normally have about 20 degrees of advance in them. Anyways I went to the Parts store and just ended up trying a VC-236 Vacuum can that starts around 5-7 vacuum and has a max advance of 9 degrees, and hooked it up to a port on the carb that has vacuum at idle and am very happy with the result. Automatically bumped the idle about 100 rpm and did take some of the “cool” sounding lope away, but I can let it idle a very long time without going above 205 degrees and the car even seems a little more crisp when deciding to goose on it and take off from a cruising rpm! There’s no knock whatsoever that I can tell, so may have got lucky with my first try and this $12 part. Thanks for the input as always!!