Starting on the 1972 Mach 1

[1973grandeklar]

I have now got the 72 Mach 1 moved to the shop and am going to start fixing it. This is a Q code and should be fun to drive!



I am going to focus on the mechanical repairs first. That way I can drive it. It is going to be a ratty musclecar thing. Rebuild of the engine is mandatory as the engine is seized. I had filled the cylinders with transmission fluid about 6 months ago. Now I pulled the engine and tore it down to find out why the motor is seized.

Found it:



Seems that these two pistons are rusted into the cylinder. Hoping I can free them and then bore this out to save the block.

I did not get a picture of the head, but it appears that there may be a cracked head. The exhaust valve in one of these cylinders is stuck open as well. I have not had time to thoroughly investigate the head, but I may need to find a replacement. These are open chamber 4V heads. Anyone got a passenger side head for sale cheap? Should I try and upgrade to the closed chamber 4V heads? How expensive would a set of these be?

I also took a peek at the transmission filter and fluid and it seems to be fairly clean. I think the C6 maybe good and I am only going to change the front seal, filter, pan gasket, and rear seal and give this a try.

 

[DK73]

Wow that is looking werry bad! Hope you are lucky that it is okay? Keep us posted on your progress [WINKING FACE] Regards DK73

 

[mach71351c]

Good deal. Keep the progress post coming.

 

[mjlan]

I don't know about your local Craigslist, but finding a replacement Open Chamber 4V shouldn't be that difficult or expensive, I see them around here (SE Michigan) for $250-$350 a pair depending on condition. The heads are the same from side to side...

How much rust is there on the body?

 

[Mister 4x4]

Check with your machine shop to see if they can extract the pistons - I had 2 seized up in mine as well, and it would've only needed to be bored to .020" over, but I kind of scarred one of the cylinder walls getting the worst one out with a BFH and penetrating oil. They might have a better technique, or a fancy jig for a press that might work better without messing up the cylinder walls.

 

[1973grandeklar]

Good news! I got the pistons out!

What I did was drive them to the bottom of the cylinder. Got a cylinder hone and ran it in the cylinder, and they popped right out. I did not score the cylinders and after a quick hone they actually look fairly good. I will have to bore it to clean out a little bit of the pitting. But it looks like no more than 0.010" to 0.020" will be required. I will get pictures this weekend.

I also got the cylinder heads tore down. The valve stuck open was not a rust issue. The valve was bent. In fact, when I tapped the valve out of the guide, the head of the valve popped off. You can see where it has been cracked for a long time, when I hit it with the hammer, the cracked propagated and the head came off. Good thing the previous owner stopped driving and this did not end up in the cylinders! Again I will get a picture this weekend.

I cleaned the heads up carefully and I cannot see any cracks. I will have the heads checked at the machine shop, but it looks like a set of new valves, guides, and put in hardened exhaust seats these heads will be OK as well.

Provided the shop finds no cracks, and me doing the labor and assembly myself, I will have this engine back in service for about $2k. This will be a stock rebuild using the factory intake and factory four barrel. The pistons will be sealed power hypereutectic, double-roller timing chain, and a stockish camshaft.

Which brings me to my questions for the forum: What is the best camshaft/lifters to use with the stock combination? This is also a stock C6 auto, 3:25 rear end, stock manifolds and stock dual exhaust. Also, what does the group recommend on the rocker arms/valve springs/pushrods? Re-use stock or upgrade. Will the addition of roller rocker arms require head machining to modify the pedestal?

One last question: The flex plate looks good, no cracks, but the starter teeth look a little worn. What is the replacement? I see a couple of differing kinds (28 oz vs 50 oz). Does that apply to the 351C? Or are the ads just misleading when they state 302/351. I know the 351W but I have seen a couple of ads on eBay stating the 351C is the same as the 302?

 

[computercarguy]

One last question: The flex plate looks good, no cracks, but the starter teeth look a little worn. What is the replacement? I see a couple of differing kinds (28 oz vs 50 oz). Does that apply to the 351C? Or are the ads just misleading when they state 302/351. I know the 351W but I have seen a couple of ads on eBay stating the 351C is the same as the 302?

Somebody can correct me if I am wrong but I believe Ford went to the 50oz with the small block in the 1980's. Ours take the 28oz.

 

[Hemikiller]

The Q-code engine with an automatic has a special hi-stall torque converter that was smaller than the usual C-6 fare, so you have to get the correct flexplate to match. Not sure if they are available still.

Every engine in the 71-3 lineup was 28oz imbalance.

The stock CJ cam was pretty good, except in '72 it was indexed 4* retarded. Specs were 270/290, .488"/.488".

I had great luck with a Sealed Power cam that was 214/224, .510/.536. Great all around power and very good manners. Had that engine in four cars over the years and it did very well, just don't couple it with a 1500 stall converter. I wouldn't go with anything larger than that if you intend to keep the stock CJ converter.

You can re-use the stock rockers, they work fine, but I would get the Crane adjustable stud conversion kit if you don't want to spend the money on machining the heads. The Boss rocker pivots might still be available, I used them once and it worked out with zero issues.

Ditch the stock valves and upgrade to one piece units and single groove keepers. As you found out, the heads have a tendency to pop off. Be very careful what you buy, some will require a bunch of machine work to work properly, other stuff is offshore junk. Ferrea and Manley make good stuff.

 

[1973grandeklar]

Thanks for the info Hemikiller. My current flex plate does look OK, and the gear teeth would probably be OK for another 50K or so (long enough to determine if the C6 is good). So given the information you shared, I will re-use what I have for now. I know it fits and is correct.

I was planning on using Manley valves. I will inspect my rockers carefully. They look to be in good shape. However, I was thinking of replacing the push rods. What is the stock length?

 

[1973grandeklar]

Here is some pictures that I promised. Notice the valve, this baby was hanging on by a thread until I popped it with the rubber mallet and the head came off:



This is the exhaust seat and port for this valve. I think this may require some checking for cracks and a new hardened seat installed.



Also here is the cylinder that had the stuck piston. I think a quick oversize bore will clean this up. Hopefully about 0.010 to 0.020 will clean it up.



As a side note, I started cleaning up the engine bay and will need to weld in a new battery box, fix/replace the cowl (non-A/C), and put a small repair patch on the radiator core support (near the battery box). The rest of the aprons, frame and cross members look to be in good shape. Will know more when I get the bay stripped down to bare metal and epoxy primer it.

 

[1973grandeklar]

Update to this build.
I have passed this car onto my son. He builds race cars for a living and he was excited to get this car.

However, bad news here. We checked this car over and did a bunch of measurements. This car has either been rolled, severely t-boned, or just overall wrecked. The last known registration was 1985 (based on the last inspection sticker on the windshield). The roof has been replaced (very poorly), the c-pillars are all twisted, the rear package shelf is skewed from side to side, and the bottom of the car is rusted badly. The cowl is completely rusted and the a-pillars are also twisted. The front core support is rusted and the battery apron is mostly gone.
With that, it was decided to simply straighten the frame so the car will drive straight. We measured all suspension connection points and had to do one minor pull to get this in alignment. The exterior will be left as patina as possible. All the rusted structural panels will be replaced and fit as best as possible (with the car tweaked the floor pans needed some "fitting"). We added subframe connectors, roll cage, and some additional floor pan re-enforcements to hold this car rigid. I will post a bunch of pictures a little later.
This car is being set-up for drag racing with a little bit of street driving. With that, I will anger a lot of you with this statement: The Mach 1 is getting a LS engine, 4L80e transmission, twin turbo set-up. The goal is about 1000 hp with the turbo set-up. De-tuned for street driving and all controlled by a Holley TerminatorX system. By the way, we are planning Dakota digital dash to keep the dash looking somewhat stock.

 

[Hemikiller]

Run it.

With a little creativity and a set of custom valve covers, 99.9% of people wouldn't know it's an LS. FWIW, lots of Cleveland guys running turbos use LS exhaust with the C flange welded on.

 

[1973grandeklar]

As promised more pictures.
Front aprons and core support on, floor pans done, trunk done, quarter patches on, rear tail panel replaced, suspension being rebuilt, new weather stripping being added, and more to come. Roll cage (yes the rear trunk divider is gone as the roll cage will extend through to the rear frame rails), remaining glass and weather stripping, new gas tank and fuel system (electric fuel pump for fuel injection). Finish the brakes, start electrical, add tires, and put on front fenders. Hope to have initial start-up April 2022. Goal, have this ready to drive to Mustang week at Myrtle Beach, SC July 25-31, 2022 (last one?).
One can also see in the pictures large sections of bondo patches that have been removed. These were cracked and rust forming underneath. Best to expose them and we just clear coat the area to seal it off, no repairs planned. One can also see how badly the rear roof seam was done when the roof was replaced.

 

[71ProjectJunk]

Nice work

 

[timachone]

Nice work and build!

It's that you saved it from the crusher and will sent it to the track and street what counts! One more saved and one more that could race! Respect you manage that much of a work to a twisted, rolled and rusted car like that. Well done - will looking forward to your build, keep us posted, please!

 

[RacerX]

Beautiful work so far.
Inspiration to get back to work on my cars.

 

[1973grandeklar]

Just a quick glimpse under the hood! Fits perfect, exhaust coming forward for turbos. Will run an electric power steering pump from a Volvo set-up.
FYI, had to use the front sump oil pan from GTO/Holden and make sure the engine is far enough forward to clear the cross member, but also clear the OEM steering linkages at the back of the oil pan. Very tight fit underneath the engine, lots of room around the sides, and just the right clearance for the hood.

 

[Bill Perkins]

Just a quick glimpse under the hood! Fits perfect, exhaust coming forward for turbos. Will run an electric power steering pump from a Volvo set-up.
FYI, had to use the front sump oil pan from GTO/Holden and make sure the engine is far enough forward to clear the cross member, but also clear the OEM steering linkages at the back of the oil pan. Very tight fit underneath the engine, lots of room around the sides, and just the right clearance for the hood.
View attachment 58227

Great Job, a lot of work going into this build

 

[1973grandeklar]

Wanted to share this bit of experience:
We ordered seat platforms to add to the car. I ordered from a reputable vendor the Dynacorn platforms. What I got were these cheap knock offs:

These do not fit with out a lot of "tweaking". I know many sell these as the alternative to the Dynacorn, but avoid them. I did complain to the vendor and they realized their mistake and did send the Dynacorn version (bottom black one):

Trying to save a few bucks is not worth it. However, my son decided to build a custom seat platform to fit his racing seats. His issue is he is 6'7" so he needs the seat as low as possible and back as far as possible. He is leaving the rear seat out of the car so the drivers seat will sit far enough back. When he gets that portion done I will post pictures of his seat mounts. I now have new seat platforms for the 73 Mustang seen in the background of some of the pictures. I hope to get that project restarted summer of 2022. My son has practice on this car and will help weld the 73 back into shape. Luckily, the 73 is straight, just a lot of rust...

 

[1973grandeklar]

Just got the electric power steering pump. Figure out a place to mount this and trial run it:

Nice thing here is all we need is a battery and we can test this. No wiring or engine running required. Getting tires mounted and put this on the ground and then run the steering. We plan on getting the steering column installed soon as well. More pictures coming. One hold up on this project is the roll cage keeps getting back ordered! We want to hold off on any interior, glass, or fuel systems until this bit of welding is complete.