1969_Mach1

After all this, I don't think it was ever mentioned what type of Holley was on there before, since this new carb has made such a difference?

Nothing wrong with kits as long as the parts are good quality. Kits were not around when I did mine. On a side note, since your Mustang does not have factory front disk brakes, are you certain it's a Mach 1. I've haven't seen Mach 1's without factory front disk brakes. That doesn't mean they weren't offered with drum brakes, it's just my observation.

In my opinion, if the lower control arms are the only upgrade to tubular, it is not worth the extra cost. I rebuilt the front suspension in my Mach 1 with OEM Ford and MOOG parts. It was a long time ago and that is why I was able to purchase control arm assemblies and lower spring perches from Ford. If I were to do it again I would go with the OEM style control arms that have been reinforced. A few companies sell them, Maier Racing is one that comes to mind. Whatever you decide, if not tubular, stick with MOOG or Raybestos brands as much as possible and not their lower end line of products.

I use to run a 750 vacuum secondary on a 351W 4 speed in my Mach 1. I now use a 700 cfm Holley mechanical secondary and have also tried a Holley 650 cfm mechanical secondary carb. In my case both mechanical secondary carbs outperform the 750 vacuum secondary. Whatever you choose make sure it has provisions for the kick down linkage for your C6. The Holley ultra double pumpers are set for the auto trans kick down linkage. If you're set on the idea of a vacuum secondary Holley, people seem to have good luck with the older 780 cfm Holley, list 3310 and not 3310-x where x is 1,2,3,4... Its basically a 750 vacuum secondary with down leg boosters instead of straight leg boosters and also a secondary metering block. For some reason it works a lot better then a 750 cfm vacuum secondary.

That's correct, you need a different proportioning valve for front disk brakes. Since you are installing original front disk brakes I would install an original proportioning valve for front disk brakes and be done with it, no tinkering and adjusting.

I agree when your seeing 351M, it's referring to a 4 barrel 351 Windsor motor. Check your vin tag on the dash. I don't recall the exact character, but it is probably an 'M', which is a 4 barrel 351 Windsor. I've never heard or read in any of my Mustang reference books about 351 Cleveland motors being installed in a 1969 model year Mustang.

If your referring to a small, about 1/4 inch diameter port, a metal tube or sometimes hose would connect to it and go to the hot-air automatic choke on the carburetor. Air would simply pass through the tube and be heated by the exhaust manifold. The hot air would heat the bimetal spring in the choke causing the choke to open. The fitting doesn't pass through to the interior of the exhaust manifold and is usually just left open when any other type of choke, i.e. electric, manual, is installed.

Not trying to hijack this thread. But mine in a 1969 Mach 1 looks clean, the contacts seem to work, but it is locked up. What causes that? I cannot even move the hands with the knob to set the time.

Not trying to hijack this thread. But mine in a 1969 Mach 1 looks clean, the contacts seem to work, but it is locked up. What causes that? I cannot even move the hands with the knob to set the time.

Unless your getting a good deal on the 1976 motor, you might want to consider a 1985 or newer 302. Only because 1985 and newer 302 blocks are hydraulic roller cam compatible. Lastly, if you have a manual trans with stock clutch linkage, the newer blocks do not have the threaded boss for the bell crank pivot and you would need the retrofit bracket for it. NPD and other Mustang parts stores sell it.

Unless your getting a good deal on the 1976 motor, you might want to consider a 1985 or newer 302. Only because 1985 and newer 302 blocks are hydraulic roller cam compatible. Lastly, if you have a manual trans with stock clutch linkage, the newer blocks do not have the threaded boss for the bell crank pivot and you would need the retrofit bracket for it. NPD and other Mustang parts stores sell it.

Unless something is wrong with the thrust plate, that is the same conclusion I come to when putting mine together.

Unless something is wrong with the thrust plate, that is the same conclusion I come to when putting mine together.

There is not much that effects the end play, thrust plate and cam timing gear come to mind. Not related to the end play but when I set up my 351W with a hyd roller Ford Racing tech told me I didn't need a steel thrust plate. Using a Cloyes True Roller timing set, ford Racing X303 Cam and stock thrust plate mine came in at 0.006".

There is not much that effects the end play, thrust plate and cam timing gear come to mind. Not related to the end play but when I set up my 351W with a hyd roller Ford Racing tech told me I didn't need a steel thrust plate. Using a Cloyes True Roller timing set, ford Racing X303 Cam and stock thrust plate mine came in at 0.006".

That makes sense. I thought I would throw it out there in case after a timing curve is obtained and a hesitation is still there. Like you mentioned, sometimes more than one thing contribute to a problem. I thought of the secondaries opening too fast. But I thought the hesitation was off idle (or close to that) and it's not common for vacuum secondaries to open too soon on untampered Holley carbs.

That makes sense. I thought I would throw it out there in case after a timing curve is obtained and a hesitation is still there. Like you mentioned, sometimes more than one thing contribute to a problem. I thought of the secondaries opening too fast. But I thought the hesitation was off idle (or close to that) and it's not common for vacuum secondaries to open too soon on untampered Holley carbs.

Changing your timing has made a big difference. After you and barnet468 get the timing curve where you want it, if you still have a hesitation you should look into tuning the accelerator pump in your Holley carb. The hesitation you mention is sometimes because there is not enough fuel from the accelerator pump when you floor it. For example, accelerator pump nozzle slightly too small, wrong accelerator pump cam that operates the linkage, or maybe the accelerator pump linkage is not adjusted correctly. It is common for Holley carbs to need some tuning on the accelerator pumps. Usually one or two sizes larger on the nozzle and/or a different accelerator pump cam than what came on the carburetor when it was new. What happens is the motor gets a big gulp of air and not enough fuel when you step on the throttle. Eventually, as the motor picks up some speed, fuel starts flowing from the main booster venturies and then like you said it "reacts like a caged animal." Reread your Holley book on accelerator pumps it should have good instructions how to tune it and adjust it.

Changing your timing has made a big difference. After you and barnet468 get the timing curve where you want it, if you still have a hesitation you should look into tuning the accelerator pump in your Holley carb. The hesitation you mention is sometimes because there is not enough fuel from the accelerator pump when you floor it. For example, accelerator pump nozzle slightly too small, wrong accelerator pump cam that operates the linkage, or maybe the accelerator pump linkage is not adjusted correctly. It is common for Holley carbs to need some tuning on the accelerator pumps. Usually one or two sizes larger on the nozzle and/or a different accelerator pump cam than what came on the carburetor when it was new. What happens is the motor gets a big gulp of air and not enough fuel when you step on the throttle. Eventually, as the motor picks up some speed, fuel starts flowing from the main booster venturies and then like you said it "reacts like a caged animal." Reread your Holley book on accelerator pumps it should have good instructions how to tune it and adjust it.

You might Perogie Enterprises for you missing vent pieces. They are not the cheapest, but usually have what you need.

You might Perogie Enterprises for you missing vent pieces. They are not the cheapest, but usually have what you need.

You are correct in that they all do not have a adjustable secondary idle mixture circuits. All the Holley's I've seen without adjustable secondary idle mixture circuits have fixed secondary idle mixture circuits. Sometimes referred to as a constant bleed circuit. I've read the reason is to maintain a constant fresh fuel supply in the secondary fuel bowl during time periods when the secondaries do not get opened. That seems reasonable. But in extreme cases you can have a situation where the secondaries are open too far to obtain a desired idle speed. Then as you mentioned drilling or installing Holley's predrilled throttle plates are needed to let more air into the motor at idle.

You are correct in that they all do not have a adjustable secondary idle mixture circuits. All the Holley's I've seen without adjustable secondary idle mixture circuits have fixed secondary idle mixture circuits. Sometimes referred to as a constant bleed circuit. I've read the reason is to maintain a constant fresh fuel supply in the secondary fuel bowl during time periods when the secondaries do not get opened. That seems reasonable. But in extreme cases you can have a situation where the secondaries are open too far to obtain a desired idle speed. Then as you mentioned drilling or installing Holley's predrilled throttle plates are needed to let more air into the motor at idle.

I haven't had time or motivation to perform an FEA analysis on the LCA and strut assembly. It's a complex system to thoroughly model and analyze. I made my initial comments because intuitively, my thinking is without a bushing there is a greater chance of long term fatigue failure issues at the attachment. I'm not sure yet if the Falcon hitting the tree incident is in line with what I was thinking.

I haven't had time or motivation to perform an FEA analysis on the LCA and strut assembly. It's a complex system to thoroughly model and analyze. I made my initial comments because intuitively, my thinking is without a bushing there is a greater chance of long term fatigue failure issues at the attachment. I'm not sure yet if the Falcon hitting the tree incident is in line with what I was thinking.