Ask Away! with Jeff Smith: How to Tune the Idle Speed on a Self-Learning EFI System
I recently bought a FiTech Go EFI fuel injection system for my big-block Chevelle. The engine is a 468ci big-block with a mild hydraulic roller cam, a TH400, a warmed-over converter, and 3.55:1 gears in the 12-bolt. I used to run an 850 Holley. It ran great but always was rich. We installed the system
Ask Away! with Jeff Smith: How to Choose (or Build Your Own) PCV System to Control Oil Vapor
I have a 472-cubic-inch engine in my ’69 Cadillac and I have a problem with oil vapor covering my nice new aluminum valve covers. I had a PCV valve on the engine, but at highway speeds it would sometimes push out the dip stick so I removed it and just put a big breather on the
Ask Away! with Jeff Smith: Vacuum Advance and How it Relates to Part-Throttle Timing
Our tech column seems to be gathering quite a following of guys who want to know more about their cars and engines. One reader posted a comment (below) in response to my answer about ignition timing curves. The original post was roughly a year ago and has resulted in over 20 comments on the answer.
Ask Away! with Jeff Smith: Converting a Draw-Through Carburetor to Blow-Through
I have a 850 Mighty Demon carb marked BC 56. The carb is designed for use with a Roots or draw-thru supercharger. I want to use it for blow-through using a hat. From pictures I’ve seen, it looks just like a blow through carb except for the milled tracks going to the throttle shafts. What must
Ask Away! with Jeff Smith: How to Increase Compression on the Cheap
Is there a cheap way to increase compression on my small block Chevy? I have a 350 small block with iron heads. I don’t know much about the engine because it came in the car. The previous owner said it was rebuilt and has a cam but he couldn’t remember the specs. The other parts
Ask Away! with Jeff Smith: A Step-by-Step Guide to Curing Engine Hesitation
My neighbor kid just bought a ’69 C10 pickup with a 350 small block with a Holley carburetor an aluminum intake, cast iron exhaust manifolds, and a TH350 automatic. He’s been driving it around when the weather’s nice and since I’m the old guy in the neighborhood with a couple of hot rods, he comes
Ask Away! with Jeff Smith: External Fuel Pump or In-Tank Fuel Pump for My EFI?
I’m thinking of installing an electric fuel pump in my ’69 Mustang. It has a small block and carburetor on it right now and eventually I’m going to run one of those self-learning fuel injection systems that bolt-on in place of the carburetor. It seems to me that it would be a lot simpler to
Ask Away! with Jeff Smith: Swapping a 4.8L LS into a 1955 Chevrolet
I have a ’55 Chevy that was my dad’s and now it has come to me. The car has a very tired 283 small-block in it with a TH-350 trans. I want to update it with a better engine and I just ran across a used 4.8L LS truck engine out of a 2002 pickup.
Ask Away! with Jeff Smith: Crate Engine or Junkyard Rebuild for a First-Time Engine Build?
I have a ’72 Ford pickup that I’m slowly upgrading. It was originally a 6-cylinder truck and still has the original automatic I want to build this truck as a fun father- and-son project so I’m looking for suggestions. I’m thinking that a small block wouldn’t be a bad way to go. We don’t need
Ask Away! with Jeff Smith: Rotor Phasing and How it Relates to Aftermarket EFI Systems
If I’m using timing control on my FiTech EFI, why do I need to buy the adjustable MSD rotor? Can’t I just lock out the distributor and then ensure the rotor aligns with the Number 1 spark plug terminal and make final adjustments to sync timing with the ECU using a timing light? Or, could




Stay Connected