Chevy C10 Truck Forums banner
1 - 6 of 6 Posts

·
Registered
Joined
·
72 Posts
Discussion Starter · #1 · (Edited)
Hey Guys,
A little embarrassed, to ask this question. Need a little help on why my SBC 350
isn't running as it should.

Issue:
After shooting the factory timing (New GM Performance SBC 350 Base Engine) 10deg BTDC & 32 total timing

Truck idles sweet and smooth. But it runs a rich, exhaust smoky, not blue, just black. You can see and smell the exhaust.

Truck runs rough when going up a slight hill it will lose power and the carb will sputter a little small light backfire . On Flat road its a little better but still not smooth.

runs a little hot (need a number temp. gage vs the stock idiot light. Not overheating or steaming.

Equipment:
New Crate SBC 350 Base model
New Weiand Team G Intake 0-7000 RPM
New Edelbrock 1405 Carb
New Headers
New Starter
New Waterpump
New Summit Racing Harmonic Balancer
New MSD HEI
New MSD Plug Wires
New Everything and running bad LOL

Cant figure this out. Took the dist. out to start from scratch on the timing. Excellent position not sure whats going on here. more than five times.

Maybe someone can say "You forgot this or that" LOL Banging my head againt the Hood LOL

I am thinking of replacing the wires, spark plugs and dist. These items except for the spark plugs came from another person that had a BBC and decided to go to a new 572 big block.

A friend told me that person had the same issue on a 402 Big Block it would backfire run rough till it warmed up. He decided buy a new engine.

Thanks guys
 

Attachments

·
Administrator
Joined
·
3,966 Posts
Sounds more like either Vacuum advance...( is it working as should...?) pull the rubber hose from the carb and suck on it, no resistance it is toast.. and or carb flooding ( float adjustment ) metering rod either wrong one or hanging up. Check for vacuum leaks around carb and intake, either by propane torch (unlit) or carb cleaner spray can around these areas. If there is a vacuum leak the engine will suddenly speed up or smooth out ...the propane torch is a little cleaner than using carb cleaner...

Get yourself a vacuum gauge from your local auto parts store, ( tuneup gauge ) its invaluable for trouble shooting...http://www.earlycuda.org/tech/vacuum2.htm

One other thing noted from your pic, you are using the ported vacuum port on the carb, have you set the distributor for ported vacuum or standard vacuum which would be on the other side of the carb,,,and the ported port blocked off..here`s some reading for the night..
http://chevellestuff.net/tech/articles/vacuum/port_or_manifold.htm
 

·
Registered
Joined
·
6,754 Posts
YEP all of what Rich said sounds like a vacuum problem.
Your likely to have an over heating problem as you go along running with out scroud
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #4 ·
Hey Guys,

Thanks, No I took off the shroud due to timing and getting to the harmonic balancer to line up the marks.

Thanks 406 Rich Ill definitely read up on the link tonight. With two little girls and family I am always asked to take care of something in the house LOL

I found the issue it was the used Distributor from the other guy as mentioned. I had a brand new one and went to summit racing to buy a new set of plugs and wires to cover all bases.

Came back, after family time and installed everything, set timing and BOOM!! She runs like a Champ! Thinking the coil was going out of the old MSD or something.

Thank you guys and yes I did pick up a vacuum gage as well

Thank guys

Tony
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #5 ·
406 Rich,

Thank you for that article you shared with me on timing. Really great stuff!!!!! And I learned a lot for that article.

Thank you guys

Best.

Tony
 

·
Administrator
Joined
·
3,966 Posts
Glad everything worked out for you, now don`t go away and become a stranger, even if its just changing a lug nut you can post it with pics... beer
 
1 - 6 of 6 Posts
Top