Old_skool_SBC

OK here we go once again
Here are the Specs. Of this Problem That After So Much I Can't Understand.

This is in a 69 350 block, Sitting in a 1982 Camaro...

-Edelbrock 600cfm carb
-Torquer 2 intake manifold
-Trw forged pistons .030
-Comp 230 236 490 490 @ 110 flat tappet
-Dart iron eagle platinum heads 200cc
-Long tube headers with true duals
-Msd rotor with delco cap

Timing set to 0Degree TDC on both Cam and Crank. Advanced about 12 Degree without Vac Advance. (BTW If advance is off Cannot and WillNot Idle)
Well if I leave advance on Port and set idle to about 1000 when i get to aboutu 2000 I am having a major stumble, As soon as i drop into a gear, the thing Stalls...
Seams like i am loosing all vaccume, Even if i change the meetering rod and spring in the carb.... WTF is my issues...

I have adjusted the Timming The Carb, Almost everything is where I thought It needed to be But


Any help here??? I can't take this car anymore

1_bad_TA

iTrader: (6)

Something is fubar with the timing it sounds like. What do the plugs look like?

1997bird

iTrader: (2)

Is your vacuum advance hose hooked up to the full time vacuum port on your carb?(this would cause the car to stumble as it will go to full advance at the wrong rpm) The other thing that I would start looking for is a vacuum leak off of the carb base gasket or intake manifold gasket.

T/AWS6969

when was putting my 391 together i got the distributor 180 degrees ( backwards) , i was pulling my hair out trying to figure it out. Just something you might wanna check

Old_skool_SBC

Thanks Sooo Far, My first Issue was being 180 Out...I got that fixed thanks to a kick a$$ friend.. with the wrong port on the carb, Either or its runing at full advance>? whats up with that??

I do tho have a 1inch spacer between the carb and intake, but i have all new gaskets... every single one is new.

as of rite now the plugs are black as hell...


Help .....

xdamxincx

iTrader: (1)

are you using a timing light ? and if so whats it reading at full advance?

Old_skool_SBC

ok this is the problem... if i disconect the vac advance and get it to idle (1000rpm) i get it OK at about 8-10 ATDC. But as soon as the vac is on it shoots up to about 25-30 ATDC and idle is about .... ummm 2500ish... oh and rite now i have no idle when its cold or in gear.

82 camaro

Your vacume advance should not take away timing. Are you tring to say BTDC or ATDC? Also is this an old cumputer controlled dissy? You are going to need from 34-38 BTDC deg of total timing or at full adv.

capn smokey

iTrader: (1)

A decently cammed engine needs alot of timing in low-rpm light load situations usually, my engine runs great at 30degrees at idle. Also you should check and make sure your fouled out plugs arent causing the issue, what plugs are they? Its just a process of elimination to sort these kind of things out, dont get frustrated and just go in a logical order making sure every possible issue is eliminated. Also drop your idle down to 1000 or so, at 2500 you are getting alot of mechanical advance and that could be confusing you. Good luck, trust me we have all been in your shoes at one point or another.

Old_skool_SBC

ummm.... your correct (my brain died there a few times) i am talking about BTDC (meaning that when i hit the harmonic with the timing light is moving twords the pass side) but without the vac Advance hooked up it has noooooo power. and as soon as i do hook the line up the thing advances right off the back.. So how does that make sence? so if i set the idle to 1000rpms with the advance on its about 25-30ish..

82 camaro

Are you shure your ballincer is the right one on some of the late model small blocks you had the timming pointer behind the water pump. Or maby you have a bad ballincer the outer ring can slip causing all kinds of hell.

Old_skool_SBC

this is the ballincer off of the 69 block. the timing pointer is on the driverside behing the waterpump located on the the last 2 bolts of the timing chain cover. as to it being bad, i wouldent think it was i checked it out when i took it off and i didnt see any stridiations on the outer ring indcating any kind of stress

tug686spd

iTrader: (11)

might sound stupid but the last time i dusted the old 327 off i went through the same thing, while dropping the distributer or adjusting timing i knocked the vaccum cap off the 3/8 stem (center back bottom of carb) who knows could be that simple was in my case

82 camaro

I have seen the stock balancer slip and it is very hard to tell. Sometimes you will notice the rubber will start to work its way out but not allways.

Old_skool_SBC

well about the balancer... when i put the cam in before the heads were on i set #1TDC and the Cam and crank were lined up, I put the balancer on the crank and i was lined up with the 0degree mark on the Pointer... So hopefully that means i have a good balancer.. If not ima pull my hair out.


This is a Edelbrock 600CFM carb. Model 1406 the ports are inthe front.. Left is ported and right is maninfold ( to my knowlage) i just read soemthing that said i need to hook my vac advance stright to the maninfold. That as i read should boost my Man vac to the Dis by 15 degree... Not the 5.5 /6.5 created by the Car4b man vac port... I dunno

chevrunner21

iTrader: (1)

idk if your already on but try gonedragracing.com they helped me out when i had my 1980 cutlass with just a 350sbc intake carb exhaust. and than they set me up with this site when i started playing with ls1.

1997bird

iTrader: (2)

It sounds like you have your vaccum advance hooked up to the wrong port (full time vaccum). When you time your engine you need to disconnect the vaccum advance hose and put a vaccum cap on the carb. After you have the engine timed, you need to connect the vaccum advance to your part time port on the carb. The part time vaccum port is located on the driver's side vaccum port on the front of the carb. When you connect the vaccum advance to a full time vaccum port you move the mechanical advance plate inside of the distributor. This will give you almost full timing at the incorrect time and make the engine stumble at low rpm.

LS1 Coupe

On a personal note, I never use vacuum advance on a performance engine, most dizzys have some built in capabilites to advance with out using the vacuum advance and the vaccuum advance will give it even more advance, usually more than what is needed for a performance engine needs, Vacuum advance is usually more suited to normal style in city driving. I would try to bypass this first instead of dwelling on it, if your determined to use it do it after you get the engine performing, Next item is the carb, edlebrock carbs are not performance carbs, they are economy carburators and very suspectable to fuel line pressure, I believe 4lbs is what is recomended, if your fuel pressure is to high they will dump fuel.

1997bird

iTrader: (2)

They will start to flood when the fuel pressure goes above 6 to 6.5 lbs.

AlLtHiRdGeN

If all else fails just try using a dizzy with a locked curve, I ran my engine for a long time with a locked out curve and it ran great.