Could this be the cause of my carburetor problems?
Could this be the cause of my carburetor problems? 
I'm not sure of the [Felpro]part number of these gaskets, but I got them from Autozone(I think). Does it look like these my have been causing a severe vacuum leak? I used to spray WD40 around the intake, but it never made much difference. The gaskets look blasted to hell. What part # do you guys use? Also, is the intake supposed to look that black on the inside? The inside of my intake looks like the exhause ports on my heads, covered in black soot....it's as black as the black paint I put on the outside. It looks like I painted the intake black inside and out(really). Tell me what ya'll think.
Last edited by team39763; Jan 14, 2009 at 10:55 PM.
definitely looks like a vacuum leak, i too bought the fel-pro orange gaskets but haven't run them yet. Almost looks like you didn't torque them down in the proper sequence and they moved a bit on you. Did you use a torque wrench as well? I typically use propane out of a canister with it open but unlit instead of brake clean/WD40/etc and have found it to detect small vacuum leaks much easier because the motor will rev up immediately.
it def looks like they could cause a problem-did you torq the bolts down, in the proper seq? if their to tight, it can squish them-replace them see what happens-also make sure your jetting the carb right
i used the felpro gaskets fron an auto parts house, cheaper than what the General charges, even at mt cost
i used the felpro gaskets fron an auto parts house, cheaper than what the General charges, even at mt cost
Yes I tightened them in sequence, but I didn't have a torque wrench. A neighbor of mine came over and tightened one up and said tighten the rest this much and you'll be good. I'll go barrow a torque wrench. So the Felpro's are the same as the GM ones? The directions say to use only the GM ones, so I was gonna pay the $80+shipping for them this time.
Based off jetting I see everyone else running, I should be close to good or a little lean. I've never been able to read the plugs since they would foul almost immediately. There was only one time that they didn't foul and that was the first time I took it out for a run almost a year ago.
Based off jetting I see everyone else running, I should be close to good or a little lean. I've never been able to read the plugs since they would foul almost immediately. There was only one time that they didn't foul and that was the first time I took it out for a run almost a year ago.
Last edited by team39763; Jan 15, 2009 at 07:52 AM.
post up your jetting, carb, air bleeds, mixture screw settings, cam, vacuum at idle, etc and I'll help with your fouling issue if you'd like. Also need to know the cam specs and timing at idle. I have some spare time tonight if you post by then for me to reply. Or if you want to give me a call I can help you over the phone. 
Jets - 70 / 76
power valve - 6.5
squirters - 35 / 31
ACC Pumps - 50cc+brown cam / 30cc+green cam
air bleeds - stock(whatever came in a 4779-9 750doublepumper)
mixture screw settings - 1-1.5 turns
vacuum at idle - between 13-15
Fuel pressure 5.5-6.5psi
Cam is 226 cam 584 lift on a 114
timing is around 15-18*at idle I believe and I locked it at 24* from 1100 up.
Would running lean have caused the gaskets to get blown apart like that?
power valve - 6.5
squirters - 35 / 31
ACC Pumps - 50cc+brown cam / 30cc+green cam
air bleeds - stock(whatever came in a 4779-9 750doublepumper)
mixture screw settings - 1-1.5 turns
vacuum at idle - between 13-15
Fuel pressure 5.5-6.5psi
Cam is 226 cam 584 lift on a 114
timing is around 15-18*at idle I believe and I locked it at 24* from 1100 up.
Would running lean have caused the gaskets to get blown apart like that?
Last edited by team39763; Jan 15, 2009 at 04:10 PM.
I doubt that is running lean at all if that is carbon buildup from your carb setup and not oil residue from a bad pcv setup that sucks oil. The gaskets would get ruined by not torquing the intake to the right specs, I'd buy new gaskets and do it with a torque wrench, it doesn't take much pressure at all to collapse them. The jets seem fine, if it's too rich at idle try to add some more timing at idle through the MAP sensor so you can add another 8 degrees or so and it should clean up the idle as well. I would run at 3000+rpm around 26 degrees timing and see if it cleans up. If your exhaust burns your eyes at idle then either the power valve is blown or you have the mixture screws too far out, try to bring them in another 1/8turn or so and watch what the vacuum guage does, you will find the vacuum will pickup as you lean out the engine at idle to a certain degree.
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Look i use the orange felpros, didnt use a torque wrench, after the intake runners cracked on my 1st victor jr from a casting flaw, i REUSED the same felpro gaskets and i have no vacuum leaks at all. They are not bad gaskets at all. Your gaskets do look bad though.
Are you sure that you dont have a blown power valve? An intake backfire can easily blow out your power valve and cause it to run rich. I've blown 2 power valves so far in my car. Buy a new power valve and see if that helps along with replacing your intake gaskets.
Are you running a 10 micron fuel filter before the carburetor? I wasnt and it think thats what lead to my carb messing up sparadically. I am using a 10 micron filter now (about the size of an oil filter) before my Speed demon which has power valve blow out protection. I bet you just have a blown power valve.
Are you sure that you dont have a blown power valve? An intake backfire can easily blow out your power valve and cause it to run rich. I've blown 2 power valves so far in my car. Buy a new power valve and see if that helps along with replacing your intake gaskets.
Are you running a 10 micron fuel filter before the carburetor? I wasnt and it think thats what lead to my carb messing up sparadically. I am using a 10 micron filter now (about the size of an oil filter) before my Speed demon which has power valve blow out protection. I bet you just have a blown power valve.
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the felpros are just fine, used em many times. yours look like the intake might not have been cut deep enough?!?! i dont know without seeing in person.
after all this time you still havent got that engine tuned properly? your going to kill that thing. i remember months ago a 5+ page thread about your car not running right.
after all this time you still havent got that engine tuned properly? your going to kill that thing. i remember months ago a 5+ page thread about your car not running right.
I'll try again with new Felpros and a torque wrench. The power valve is still good, I just checked it. I'm running 2 of those metal Transdapt inline filters, but I'm not sure how good they are. I'm planning to switch to a better filter soon.
My intake was a "non perfect" one that needed to be sent back, but the flaws that I could see weren't that bad so I kept it. So it's possible that it wasn't cut deep enough.
Yep, after all this time I'm still messing with it. But it's not like it's by choice, I've been trying to get it right since day one. It's been over a year since I started it, so you can imagine all the times that I just wanted to burn it and crush it. I do what everybody tells me and it just never worked out. I'm hoping that the bad gaskets/vacuum leak were the cause.
My intake was a "non perfect" one that needed to be sent back, but the flaws that I could see weren't that bad so I kept it. So it's possible that it wasn't cut deep enough.
Yep, after all this time I'm still messing with it. But it's not like it's by choice, I've been trying to get it right since day one. It's been over a year since I started it, so you can imagine all the times that I just wanted to burn it and crush it. I do what everybody tells me and it just never worked out. I'm hoping that the bad gaskets/vacuum leak were the cause.
Vacuum leaks can make the whole carb tuning process a moving target. The leaks affect you most at low RPM and typically cause you to run too rich just to get the idle right.
I wish someone could have explained all that soot in the intake. Tells me you have run way too rich at one time or the other. Like said above make sure that isn't oil from the PCV. When you get things back together try a clean set of plugs and disconnect the PCV for the initial tune.
I feel your pain. I just recovered from dumping another $300 into the fuel system to clean and seal the tank and add filters. Sometimes I just want it gone. All it takes is one full throttle run to get me over that though.
I need warm weather so I can get in some consistent tuning runs.
I wish someone could have explained all that soot in the intake. Tells me you have run way too rich at one time or the other. Like said above make sure that isn't oil from the PCV. When you get things back together try a clean set of plugs and disconnect the PCV for the initial tune.
I feel your pain. I just recovered from dumping another $300 into the fuel system to clean and seal the tank and add filters. Sometimes I just want it gone. All it takes is one full throttle run to get me over that though.
I need warm weather so I can get in some consistent tuning runs.
Vacuum leaks can make the whole carb tuning process a moving target. The leaks affect you most at low RPM and typically cause you to run too rich just to get the idle right.
I wish someone could have explained all that soot in the intake. Tells me you have run way too rich at one time or the other. Like said above make sure that isn't oil from the PCV. When you get things back together try a clean set of plugs and disconnect the PCV for the initial tune.
I feel your pain. I just recovered from dumping another $300 into the fuel system to clean and seal the tank and add filters. Sometimes I just want it gone. All it takes is one full throttle run to get me over that though.
I need warm weather so I can get in some consistent tuning runs.
I wish someone could have explained all that soot in the intake. Tells me you have run way too rich at one time or the other. Like said above make sure that isn't oil from the PCV. When you get things back together try a clean set of plugs and disconnect the PCV for the initial tune.
I feel your pain. I just recovered from dumping another $300 into the fuel system to clean and seal the tank and add filters. Sometimes I just want it gone. All it takes is one full throttle run to get me over that though.
I need warm weather so I can get in some consistent tuning runs.
The black stuff is definately not oil because I'm running breathers instead of the PCV system. I took some time and cleaned off 4 sets of my old sparkplugs for tuning, so when I get it right, I can just throw in some good ones.
I'm hoping I don't have to dump anything else into my fuel system. I'd hate to redo anything else from the motor back at this point. Yep, exactly...that one good run/drive makes it all worth it again.
I just tigthened it down the way i thought it felt fine. The gaskets do not need to be compressed. I made sure my intake wasnt touching the heads anywhere (meaning the gasket was the only part making contact) and i've had no leaks. I can get the engine to idle at 600rpm if i want
Cool. I was planning to do it like that the first time, but someone warned me that 11ft/lbs is a little over finger tight...which I'm guessing is false. I should get the new gaskets in later this week, so hopefully I can see this thing running better than it ever has.
