Even if they wont withstand the full 1200 degrees, they'll still be better than it was. I bet they're just fine.

 

http://vid1298.photobucket.com/album...pshk6e89ie.mp4


This is starting to get really frustrating. 3" of vacuum now?! Have no idea why it's lower than the other day when I saw 13". I do know the cheap hose that came with the gauge likes to just crack and fall apart when I slip it over the vacuum port on the carb. Don't see any cracks in the line though? I sprayed starting fluid everywhere to check for leaks. No change. Actually, the only place left that I need to check is the brake booster. I'm going to go get some better hose for this gauge right now. Engine starts and runs great, I just don't want to start driving it if there's still something wrong. Everything else is done and this is keeping me from getting on the road.

 

I can't figure this out. Gained one whole inch of vacuum by advancing the timing to 18 btdc. If there's a vacuum leak somewhere, it's a complete mystery as to where it is. Only so many places where there could be a vacuum leak and I've checked them all a half dozen times now. The engine starts, idles smooth and runs beautiful. Late valve timing seems just about impossible to me. Plus, wouldn't late timing cause (if even occasional) a pop through the exhaust and/or carb? I've witnessed none of that since the installation of the new carb. I'm at a loss as to where to go from here. I'm ready to pull the valve covers and check the rockers (this would be literally about the 15th time) if that's all there is left? I have noticed but not sure if it's normal or not, the intake and valve covers are getting extremely hot when the engine gets up to temp. I'm unsure of what would be considered "normal" when it comes to that though.

 

You might consider a hand held vacuum gauge if you have one? Maybe your gauge is leaking, or just broken, and giving false readings. I keep a hand held vacuum gauge in my tune up kit, just for tuning, and double checks of my built in gauges. 3" seems like the engine wouldn't even run if it was correct.

 

I really am at a loss here Vall. I got better hose for the gauge and checked vacuum from the manifold port (small one), the rear port for the power brakes, the PCV port in front and got the same readings at all of them. I drove the car 3 times yesterday and it runs pretty well. Only problem I'm having is WOT, it doesn't seem to like that, yet. I was assuming it's because of the low vacuum but not sure? I don't fully understand how the secondaries on this Edelbrock Thunder series 650 work with the AVS (air valve secondaries) but sort of assumed they need vacuum to operate? If I go WOT it just falls flat on it's face. Not a delay, just coughs until I bring my foot back off the throttle. I adjusted the accelerator pump to it's highest setting already too. Whether or not the gauge is accurate, which it's a new gauge last year, it still seems like the vacuum is low. Brakes barely work until I'm driving (higher vacuum) and the vacuum advance does not appear to be working at idle when it should be. At this point however, I'm positive there isn't a vacuum leak anywhere. Late valve timing seems impossible also so I really don't know what else to do. I can get a vacuum pump if needed, but I want to be positive there isn't something going on causing this issue still.

 

that's to bad sorry to hear about this ,It should not be so much trouble ,with an older engine ,does go to show how much harder it can be .an how much longer it can take on the new engines m though with the computer an Dyanotsic tools they have for new ones are something to ,wear as for an old one there none there anymore ,hope you figure out soon,yes mabey a new vacuum.

 

Appreciate it '95, it's been the same way throughout this entire build. The easiest of tasks have all turned into nightmares. I'm just so ready to get on the road and have this Camaro perform like it should. It starts, runs and drives great but I can tell it's not at it's full potential. There's something causing this low vacuum, and being absolutely stymied as to the reason makes it extremely frustrating. I borrowed a vacuum gauge from the auto parts store a little while ago and still get the same readings as my gauge.


Here's a video clip from yesterday when I went for gas. Had a little issue with the linkage controlling the butterflies on the scoop. Wasn't lining up well from the scoop to the carb connections and it wanted to pull it sideways. Have that fixed now. I like the easy fixes! Anyway, as you can see, it does run decent, just not at WOT.


http://vid1298.photobucket.com/album...psnb8pp4yh.mp4


Having gone through the vacuum connections on the carb as well as checking for leaks around the manifold and not finding anything, are there any other suggestions on what I could check?

 

Have you called tech support at Edelbrock or your distributor manufacturer? They may have an idea that may help.

I have a couple of good vacuum gauges if you need one. If there's anything I have that would help just let me know!

 

I appreciate the offer for the gauge but after checking vacuum with this other one, I'm sure mine works fine still. I saw a vacuum pump kit at the store this evening and it said I could use it to check vacuum advance, brake booster etc. with it but I have no idea how to go about doing that? Not specifically relevant to my vacuum issue but thought it might be good to have. Maybe there's instructions inside the package, I didn't buy it yet but might grab it next time I'm there. Suppose I could give Edelbrock a call, didn't think about that since I wasn't thinking my problem was actually carb related. Guess it's worth a shot. All I know is that everything I've read or seen says the same thing - "a reading of between 3-6" indicates a large vacuum leak." I can spray starting fluid around the intake and watch it pool between the intake/heads. Same thing around the carb base/spacer gaskets. Don't mean to keep repeating the same things, just praying I can isolate this issue quickly. Having just paid a year's insurance premium and going to get the plates tomorrow, it's taken the frustration levels way above normal that I can't figure this out. If that's even possible. I looked at vacuum canisters today, those seem like they'd help the brakes but not necessarily help with anything else? I don't know.

 

I don't think your vacuum leak (if it has a leak) is at the intake, or carb base. If it has a leak, I'd question if it's internal to the carb, or distributor. Since it appears to be running well, I wonder if the issue might also be timing related, and possibly as simple as stuck mechanical weights in the distributor. It was running well at one point, so something changed, and timing would sure make vacuum drop off. I'd put a timing light on it, and see if it's sitting where you want it. Then rev the engine and see if it advances well also. Not advancing will allow it to run OK at idle, or light throttle, but kill the acceleration.