Hello all! This is my first technical question post. I just purchased a 71 Mach 1 and need advice on troubleshooting steps and where to go from here.
Quick backstory: The car is an M code with Ram Air so I am assuming the ram air was aftermarket as the wiki says the factory ram air cars are Q code. The vehicle came with basically no history so lets assume we don't know anything about its past life. The only clue I have is that at some point the factory 4 speed was swapped for a C6. The P/O claimed that it was likely they rebuilt the engine when they did the swap based on how good the engine looks. It's also possible that they just threw a different engine in when they did the swap as I have not confirmed whether the engine block number matches the vin. It is definitely a 351C 4V and has a stock split bore intake manifold. I have an in depth mechanical background specializing in diesel truck repair but have never touched a carburetor; so while I may be ignorant to how to tune a carb, I do know how to turn a wrench.
Problem: Engine runs and revs ok but when in gear, it has no power, backfires, and has a big hesitation when you hit the accelerator. None of the interior gauges work and the wiring harness is pretty hacked up. P/O claimed that a month ago they borrowed a friend's edelbrock carb to put on there (to replace the Chinese copy that was currently on there) and that it ran just fine so it just needed a new carb. I installed a new Holley 600 CFM Street Warrior Carburetor and it runs exactly the same as with the chinese carb so it would appear that there is more to the story.
Goals: I want this to be a reliable weekend driver with a good bit of get up and go. From my brief research it seems that I could easily pull 400 HP/Torque from this engine with minimal upgrades. I don't have an unlimited budget and will be trying to save on costs as much as I can but am also willing to buy high quality parts if they will last the lifetime of the car.
So far: I purchased the Holley carb and have also purchased an Edelbrock performer #2665 intake manifold. I have not installed the intake yet. I plan to install the intake and replace the ignition system and perform a tune up at the same time.
Questions:
1. What ignition system to go with? I am seeing many different recommendations on several different forums. It appears that the Ram Air will limit my choices. I like the idea of the MSD plug and play options but everything I read would make it seem that they will not fit with the ram air. How much of a difference does the ram air make? If my car didn't come stock with the ram air, should I convert it back? What distributor is recommended with the ram air? It also looks like I need to choose a distributor that is compatible with the camshaft; due to the unknown history of the engine, how do I verify the camshaft?
2. Due to the unknow history, is there a way to check the timing chain and gears without pulling the front of the engine apart? Should I just plan on doing the timing chain regardless? If I have to dig in there, should I also just do the camshaft upgrade at the same time or save it for down the road?
3. What steps should I be taking here to get this engine running correctly? My current plan is to:
-Check compression to get an understanding of general engine health
-Install edelbrock intake manifold and Holley carb (any must know advice on the intake install?)
-Install upgraded ignition system (need suggestions on what to go with)
-reset ignition timing, perform tune up (plugs and wires) and see how she runs.
-Verify healthy timing chain
Other desired upgrades: I would like to upgrade the exhaust and camshaft. Suggestions?
I am currently away from the car on a work trip so wont really be able to verify anything until I get back to town. I plan to buy the shop manuals and the 351c rebuild manuals. I did snap these photos before I left. Thank you for any and all help/advice.
Quick backstory: The car is an M code with Ram Air so I am assuming the ram air was aftermarket as the wiki says the factory ram air cars are Q code. The vehicle came with basically no history so lets assume we don't know anything about its past life. The only clue I have is that at some point the factory 4 speed was swapped for a C6. The P/O claimed that it was likely they rebuilt the engine when they did the swap based on how good the engine looks. It's also possible that they just threw a different engine in when they did the swap as I have not confirmed whether the engine block number matches the vin. It is definitely a 351C 4V and has a stock split bore intake manifold. I have an in depth mechanical background specializing in diesel truck repair but have never touched a carburetor; so while I may be ignorant to how to tune a carb, I do know how to turn a wrench.
Problem: Engine runs and revs ok but when in gear, it has no power, backfires, and has a big hesitation when you hit the accelerator. None of the interior gauges work and the wiring harness is pretty hacked up. P/O claimed that a month ago they borrowed a friend's edelbrock carb to put on there (to replace the Chinese copy that was currently on there) and that it ran just fine so it just needed a new carb. I installed a new Holley 600 CFM Street Warrior Carburetor and it runs exactly the same as with the chinese carb so it would appear that there is more to the story.
Goals: I want this to be a reliable weekend driver with a good bit of get up and go. From my brief research it seems that I could easily pull 400 HP/Torque from this engine with minimal upgrades. I don't have an unlimited budget and will be trying to save on costs as much as I can but am also willing to buy high quality parts if they will last the lifetime of the car.
So far: I purchased the Holley carb and have also purchased an Edelbrock performer #2665 intake manifold. I have not installed the intake yet. I plan to install the intake and replace the ignition system and perform a tune up at the same time.
Questions:
1. What ignition system to go with? I am seeing many different recommendations on several different forums. It appears that the Ram Air will limit my choices. I like the idea of the MSD plug and play options but everything I read would make it seem that they will not fit with the ram air. How much of a difference does the ram air make? If my car didn't come stock with the ram air, should I convert it back? What distributor is recommended with the ram air? It also looks like I need to choose a distributor that is compatible with the camshaft; due to the unknown history of the engine, how do I verify the camshaft?
2. Due to the unknow history, is there a way to check the timing chain and gears without pulling the front of the engine apart? Should I just plan on doing the timing chain regardless? If I have to dig in there, should I also just do the camshaft upgrade at the same time or save it for down the road?
3. What steps should I be taking here to get this engine running correctly? My current plan is to:
-Check compression to get an understanding of general engine health
-Install edelbrock intake manifold and Holley carb (any must know advice on the intake install?)
-Install upgraded ignition system (need suggestions on what to go with)
-reset ignition timing, perform tune up (plugs and wires) and see how she runs.
-Verify healthy timing chain
Other desired upgrades: I would like to upgrade the exhaust and camshaft. Suggestions?
I am currently away from the car on a work trip so wont really be able to verify anything until I get back to town. I plan to buy the shop manuals and the 351c rebuild manuals. I did snap these photos before I left. Thank you for any and all help/advice.
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