Jeff's 3.8 and 4.2 Projects.

Any further progress bud?

Yup, work continues on it but I just haven't had much time to put together an update for a bit. I will make some time and sort through the recent photos and bring the thread up to date with over the next couple of days.

In the interm, here is a propane powered potato cannon that I had to make for work last week on short notice. I didn't get much work on the project last week because I was very busy making that.

 
Since my last update I've successfully managed to ruin another split-port head by getting greedy with the carbide cutter to the point that even welding it couldn't save it.
Which was quite unfortunate as it was just about finished. So after another $160 including shipping, I have another head to start over with........again...........

I made the previously covered fuel injector bung mod to the replacement head so I won't cover that again but I did mill the rocker arm pedestals for pushrod guideplates and 7/16" ARP studs.



On an poorly timed impulse decision I decided to buy a stainless steel rocker arm kit from ebay for around $200 all in. It was a Pro-comp/Speedmaster retrofit 351C kit. Yes, I knew about their reputation and yes I ignored that voice inside my head. I though it might be an OK value as it didn't need pushrod guide plates or machining. So they arrived, with the packaging beat up and the studs packaging open and the studs spilling out in the box. I also thought the studs base thread (head) would be bigger than 5/16" so I could just drill and tap the bolt holes oversize. That was a mistake on my part for rushing my research because the 5/16" thread on the studs is basically the same as the 8mm thread in the head and after you re-tap the 8mm thread to 5/16" the thread is too loose to use. So then I order some Heli-coils for the heads for $30 which I then ended up sending back when I realized I would be way better off just spending an extra $25 and getting 7/16" ARP studs and machining the pedestals and buying guideplates. Why I almost trusted my engine to a tiny chinesium stud instead of a beefy ARP one just to save a buck and some time on the mill I'll never know, major brain fart on my part.

The studs had their own problems too in that they were too big to actually install a rocker arm on. Every one was 0.004"-0.006" bigger than the hole in the rocker arm. So I put each on in the lathe at cut that much off of them. This was before I learned the error of my ways and scrapped them for the ARP ones.

Out of the 16 rocker arms I found 12 that I could use due to poor assembly of the pushrod cup. It was not pushed in enough to seat it properly or bottom out. Ugh...why did I buy this junk. At least the stainless steel casting seem good enough and the bearings in it seem fine and the locking nuts on the studs are ok to use but the fun times don't end there because......



The self aligning rocker "feature" that removes the need for guideplates which is now irrelevant because I will be using guideplates does not fit properly with the stock valvespring setup. The alignment tabs sit on the retainer/keeper and the roller tip of the rocker is 0.075" away from it so it never touches the valve stem. Arrrrrgh........so now it's either machine the tabs off each rocker arm or buy longer valves and associated parts so I will be machining the tabs off the rocker arms.



I've been accumulating some parts in the interm as well such as these 304SS 4.2L F-140 headers which are of surprising good quality for a product from China. The welds and overall quality are very, very good. If needed I will cut and reweld as needed but as they are going to face forward and down for the turbo it may not be neccessary.



I also bought a turbo (GT3582 clone), wastegate and blow-off valve. All of which will be getting a full teardown and overall review here when I get the time.





After that I made some flanges for the turbo out of 1/2" steel plate.



I also picked up a set of Scat 6.125" H-beam connecting rods from Super Coupes Unlimited and some more mundane stuff from around the internet like gaskets, harmonic balancer, oil pump, freeze plugs etc.

There is an issue with the intake manifold that I need to address though. The center section bolts on to the lower via 11 fasteners which are inside the intake manifold and should one come loose it will fall into the engine and there is no way to keep an eye on them without pulling the upper manifold off.



I will not just trust it to loctite only and I don't want to weld each port to the lower manifold so I think I will machine the countersunk bolt hole to a flat bottom and use socket-head cap screws (allen bolts) drilled for safety wire and then wire them all together and add a dab of loctite for good measure. So I have some re-work to do there.
 
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I checked out the recently opened local Makerspace today. It's the first one around in my part of the country.
The monthly membership will give me access to a bunch of tools and other goodies including; Manual lathe and mill, CNC lathe and CNC mill, 3D Printers, electronics gear, Welding gear, a Waterjet machine, laser engraver and a bunch of other cool stuff.

I plan to fully embrace my new playground. So many ideas, so little time......
 
Is there any material that you can`t work on?

I would say human flesh but the makerspace robotics section had a small robotic articulating arm that takes different attachments so if I stuck a tattoo gun on there I could theoretically program it to tattoo flesh.

The 3D printers there open up some interesting options going forward. I also use one at work and they are pretty sweet as you can replicate and print damn near anything you can think of or design from flexible gaskets to large parts.

There is so many different materials you can print out of including carbon-fiber impregnated materials for extremely strong parts. You are really only limited by the size of the printer and your imagination as to what you can make. From interior bezels, bushings, small clips and brackets right up to certain engine parts or adapters. It is great for prototyping parts in plastic quickly before you commit to machining in metal.
 
I drew up a replacement thermostat flange. I will machine it and rebuild my existing one later this week and see how it goes. Should just be a matter of cutting and re-welding the existing pipes and then resurfacing the flange surface.

 
Should be easy enough for you Jeff and is a good improvement part. You can also machine an aluminum replacement for the brittle plastic under the coolant bleeder screw like TBSC is doing.
 
You can also machine an aluminum replacement for the brittle plastic under the coolant bleeder screw like TBSC is doing.
I am already planning on making one for myself. I just need to work out a few details on it and make a 3D model of it first.
 
I was able to machine the replacement thermostat flange today and weld it onto an old housing assembly.

First I had to make a fixture to hold it while I cut the profile.


Milling the small holes out.


Machining the flange out of 3/8" mild steel plate.


A flange is born.


After welding, grinding, machining the mating surface flat and a bad temporary spray job to see what it would look like. It will be sandblasted and properly refinished later on.
 
Would you be willing to make one of the cobra TB inlets? I'm building a 4.2 with single port heads (for now) and swapping into my 82 F100. I have a lot of room behind the blower so I'm planning to move the intake plenum back a bit to gain some room for a better inlet. I was gonna build one myself but you are already halfway there.
 
Would you be willing to make one of the cobra TB inlets? I'm building a 4.2 with single port heads (for now) and swapping into my 82 F100. I have a lot of room behind the blower so I'm planning to move the intake plenum back a bit to gain some room for a better inlet. I was gonna build one myself but you are already halfway there.

Did you mean just the flange to mount the tbody to or a whole plenum thing? The cobra mounting flange is no problem and I may even have a spare on the shelf. The whole plenum would be very hard to do again and still be economically feasible, lots of hours involved in it compared to buying a Magnum Powers plenum and an aftermarket tbody.
 
Did you mean just the flange to mount the tbody to or a whole plenum thing? The cobra mounting flange is no problem and I may even have a spare on the shelf. The whole plenum would be very hard to do again and still be economically feasible, lots of hours involved in it compared to buying a Magnum Powers plenum and an aftermarket tbody.

I did mean the whole plenum but I guess its gonna be too custom for that. I would be interested in just a flange though. Maybe even with single opening as well.
 
It has certainly been a while since I posted any updates but I will try and bring the thread up to date over the next few days.

There was not a great deal of things done from January 2020 until September when I finally picked up an SC of my own. It is a 1993 with a manual transmission. It is actually one I inquired about a number of years ago but could not afford it at the time. I remember seeing this car driving around my town years ago and always loved it. In hind sight I wish I had been able to buy it the first time I seen it for sale because it has been basically parked since then and rotting away underneath. It's most recent MVI expired in 2013 so I have some (lots) of work to do. The rockers are completely wasted and I think they were already done once before and there are some other spots that need patching as well but I knew that when I bought it.

Shortly before it was for sale the door was bumped by a piece of machinery which dented the door and broke the window. I found a window for it but want to fix up the door (hammer and dolly time) before I put it in so I won't break it. The car also came with the stock wheels and loads of spare parts to add to my already growing collection of parts. I believe some of the spare parts are from an SC that I swapped an engine on for a person a long time ago as the labels on the connectors look like my hand writing and I did label everything before the swap.


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The hood latch cable needed to be replaced as well while I worked on the engine and as only used cables seem to be available I had to improvise for a new one. The only way to get the hood open when I got it was with a small frayed piece of the original cable hanging down from the latch. After some measuring, research and guessing I ordered one for a Ford Fusion (2012 I think) that should be around the correct length. The latch had to be welded up due to wear but the rest of it was pretty simple. Remove the Fusion parts off the new cable and drill/modify/cut and epoxy the T-Bird parts on to it. The handle was drilled and filed to accept the new cables end and then epoxied in place. I probably could have made something to adapt it without the drilling/cutting/epoxy but I didn't have the time. The cable fits exactly although I am not sure if it follows the OE cable routing as the original was long gone.

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I figured would just give the engine a much needed tune up and then move on to fixing the rust so I would be able to be on the road hopefully by the next (2021) summer sometime. I was wrong......so, so wrong about that timeframe. The engine was rebuilt in 2001 based on the stack of receipts that came with it and I don't think it seen a lot of mileage since then.

Tune up time! This is where things went sideways and I fell down the rabbit hole. First up were the spark plugs, several of the wires broke off of the boots but that was OK as I was going to replace them anyway, then the plugs came out 2,3,4,5,6 and then back to one as it was stiffer. Crack, crack, snap. It was nice enough to take the entire hex off with it when it broke so there is no getting a socket on it anymore. The plugs were old and have probably been in there since the rebuild in 2001 and there was no anti-seize on them from the looks of it. Cranking the engine over forced the insulator out so I though that I could probably get an extractor on it. I sprayed it with penetrating oil often over a couple of weeks and then spent several days trying the extractor (straight fluted) to no avail. I could get a good bite on it but the bastard would not move even with heat.



So much for the quick tune up, off with the cylinder heads.
 
So the plan now was to just pull the heads, fix the broken plug and put it back together as I already had most of the gaskets and things on hand for the 4.2L project. I though about drilling the broken plug out but decided against it. Then came the "might as well's and since I'm already in there anyway" things. This included replacing the rad and heater hoses, replacing the bearings on the tensioners, rebuild the fuel rails, clean the injectors and replace the o-rings, replace the motor mounts and modify them to not move much anymore, rebuild the thermostat housing, replace the front stabilizer bar bushings, clean and paint almost everything, replace the belts and other things that I am forgetting such as the fuel filter and it's corresponding piece of now broken fuel line.

Pics of engine mount part before repairs.
 
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