DuPuis Family Cobra Build

You really should pay very close attention while she types in her Amazon password next time. ;)

What I really ought to do is just get the Amazon app on my phone. :)
 
I would rather build the truck. If Spike built the Hot Rod we could have all three.

The truck looks really cool. I like the idea of a mid engined small sports car, but the 818 looks too kit carish for my tastes, and I don't have the space and time to build one.
 
So, after Ted is done with his car, which one of you is going to build a car to keep the rest of us same?

It should be noted that me building another a car is almost a foregone conclusion. The question will be what and when. However once I complete the Cobra it's going to be some time before starting on the next car, if nothing else because of the other bigger dollar projects we want to accomplish.

I would rather build the truck. If Spike built the Hot Rod we could have all three.

The truck looks really cool. I like the idea of a mid engined small sports car, but the 818 looks too kit carish for my tastes, and I don't have the space and time to build one.

The Cobra is what made FFR what they are, and it's good that they've continued to work to grow and develop the company. That said, the GTM and 818 don't do it for me. I think the key to their success was looking back in time and making good quality kits that replicated classics that everyone loved. The 818 and GTM just are generic modern cars in my mind. More power to them for doing it, but if they made a GT40? Sign me up for S/N 00001.
 
My wife and I have separate amazon accounts. But somehow she was able to tag me as her spouse, so I get prime benefits on my account as well.
 
My wife and I have separate amazon accounts. But somehow she was able to tag me as her spouse, so I get prime benefits on my account as well.
They allow you to combine accounts as "family" to share the Prime benefit.
 
Got to spend a bit of time in the garage this evening. My first and primary task at hand was to confirm whether or not the runout on the bellhousing was within the spec of 0.005", which requires attaching a dial indicator to the flywheel with the bellhousing torqued down to the engine, then rotating the engine one revolution and confirming that the difference to bottom and side to side is no more than 0.005". I convinced myself that it was 0.002-0.003". I say convinced myself because with an aluminum flywheel, it was very hard to keep the mount solidly attached to the flywheel bolts (the only magnetic surface) without rocking. This would be much easier with a standard steel flywheel that provides a more consistent magnetic base. These Tremec bellhousings are known for being well machined, though, and the measurements seemed to indicate I was within spec.

The girls then came downstairs after falling asleep and then not falling asleep and then needing to go to the bathroom (this napping at preschool thing really screws up their sleep schedule) and helped me paint the two trunk panels, which I'll be ready to rivet in place after run the hard lines for the fuel. I opened the garage door for painting because of the fumes, and oh boy did I quickly notice how good the air conditioning makes things. It's cooled off but very humid. Very worthwhile investment there.

One thing I noticed (and am not quite sure how I missed) is that I don't have bolts that plug the EGR ports on my Edelbrock heads. These heads were designed to allow maintaining the EGR system on an emissions controlled car. Of course the Cobra will have no EGR system (100% of exhaust turns into noise) and so if I don't plug these, I'll have an annoying exhaust leak. So back to the hardware store tomorrow for a few bolts to plug that up. Really the best thing would be if I could just fine pure hex-head plugs instead, so I'll see what's available.

Tomorrow at the very least my timing cover should arrive from Summit, and hopefully also the dowel pins and clutch bolts. If those arrive, then I'm going to install the clutch and then maybe install the bellhousing for good. I probably won't get around to attaching the transmission just yet... maybe...

I have a feeling something is going to come up that prevents me from getting the drivetrain installed this weekend, but I'm still keeping my fingers crossed and so far so good.

There's also one port on the engine that I'm trying to figure out what it is, and maybe the answer is just a mount. But on the rear passenger side of the block, basically just above the starter, there's a port that looks like it could/should be an oil pressure port. Maybe someone here knows?

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Well, some people are jerks.

I posted the question about that hole on a Facebook group I'm on. The first response was from someone saying it's another oil pressure port and that's what he uses for his gauge.

About 5 minutes later another guy corrected him - it's a dead hole that from the factory is used for a ground strap.

I don't know why people have to do that. But good part is I can leave it alone and potentially use it for a ground strap if I want. I probably won't just because its location won't be particularly easy to access once the engine is installed, at least I don't think it will be.
 
How about spending a few minutes probing it with a straight pick and a bent pick to see if it feels like it intersects any passages? There may be more than one variant depending on what it was origionally installed in. Then if it feels solid, use a rubber tipped blow gun to pressurize it and see if the air goes anywhere, other than leaking back out around the wnd of the threads.
 
Yes, but if Ted just uses her password instead, he gets to fill her targeted purchase suggestions with go-fast car parts. :devil:
Trust me, I use the wife's account for my Amazon purchases. I go in an remove my items from her search history frequently if I'm looking at b-day/xmas gifts lol.
 
One thing I noticed (and am not quite sure how I missed) is that I don't have bolts that plug the EGR ports on my Edelbrock heads. These heads were designed to allow maintaining the EGR system on an emissions controlled car. Of course the Cobra will have no EGR system (100% of exhaust turns into noise) and so if I don't plug these, I'll have an annoying exhaust leak. So back to the hardware store tomorrow for a few bolts to plug that up. Really the best thing would be if I could just fine pure hex-head plugs instead, so I'll see what's available.

What you're looking for are called "thermactor plugs". I didn't notice they weren't in when I put my boat in for it's first test run in the water. Made a racket and a heck of an exhaust leak, lol. I was able to reach the holes with engine installed and insert the plugs.

https://www.jegs.com/p/JEGS/JEGS-Th...ll-Block-Ford-Cylinder-Heads/1686929/10002/-1
 
I've gotten enough people confirming that it's just a hole that I'm pretty convinced that's what it is. I'll do some more checks, but pretty confident that it's nothing to concern myself with.

Something I really should do is run, or at least start running, the fuel lines. That'll get me to the point where I can rivet the trunk metal in place.

What you're looking for are called "thermactor plugs". I didn't notice they weren't in when I put my boat in for it's first test run in the water. Made a racket and a heck of an exhaust leak, lol. I was able to reach the holes with engine installed and insert the plugs.

https://www.jegs.com/p/JEGS/JEGS-Th...ll-Block-Ford-Cylinder-Heads/1686929/10002/-1

That makes sense. On the front of the engine Edelbrock actually just had some long bolts/studs in there for mounting engine accessories, so I think that I can get by just fine with some appropriately sized bolts torqued into place, and I'll put some sealant on for good measure. Not like exhaust pressure is super high in this engine.
 
Correct, I think they're 5/8 coarse thread bolts if I remember correctly. I have brackets for fuel/water separator and alternator on the front of mine which bolt into those ports, so no need for plugs there.
 
Sure enough my clutch bolts and dowel pins had arrived from Amazon when I got home. I took the dowel pins and put them in the downstairs freezer (which is well below freezing) to try to get them to shrink a hair and make them easier to install on the interference fit. Not that I'd be too concerned about that going into an aluminum flywheel, but I figured it couldn't hurt.

After getting the kids to bed (all three fell asleep this time) I got the dowels out of the freezer and they went right in with a few taps with the brass hammer. Got the friction disk in and aligned, pressure plate on and torqued, then bellhousing on and torqued (with clutch release fork installed). I installed the pilot bearing last night so that was already done.

With that part ready I started trying to connect the transmission and the bellhousing together. I got the input shaft up to where the front bearing retainer was sliding into the bellhousing, but it is a slight interference fit and didn't go in 100% on its own, so I wanted to take it back off to make sure I wasn't hitting anything. The tapered front couple mm of the bearing retainer was going into the bore of the bellhousing, it just needs to be tightened down evenly with the transmission to bellhousing bolts. So tomorrow I can do that and get the two married together.

I also got the new timing cover (genuine Ford) and it is much, much nicer than the Speedmaster one that came with poor machining. As an added bonus, it also has provisioning for a crank position sensor if I decide to go with EDIS ignition like I'm thinking. That's a good thing. I need to do a little machining work on it (standard with the timing gears) and then I can bolt it on.

The oil pan hasn't arrived yet (not surprising), but I'm thinking tomorrow I'll see if I can teach my son to help me bleed brakes, get the timing cover on, and mate the engine and transmission together. And even better if I can do it, also finish up getting the intake drilled so it can get put on the engine. However I don't want to bolt it down until the engine is in the car just to help clearance wise during installation. We'll also see how interested the kids are in helping - this may be too ambitious.

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Well, some people are jerks.

I posted the question about that hole on a Facebook group I'm on. The first response was from someone saying it's another oil pressure port and that's what he uses for his gauge.

About 5 minutes later another guy corrected him - it's a dead hole that from the factory is used for a ground strap.

I don't know why people have to do that. But good part is I can leave it alone and potentially use it for a ground strap if I want. I probably won't just because its location won't be particularly easy to access once the engine is installed, at least I don't think it will be.
The same sort of thing happens in any group/forum, including this one.
 
Today I went ahead and attached the engine and transmission to start. Then I ground down the timing chain center part on the new timing cover and confirmed fitment. Of course then I found out that the bolts I have to hold it in place are metric and not standard (Ford changed it in the later blocks), so I need to get a new set. No big deal, I can put those in later.

Then I ground down the sides of the intake to get it to fit and checked the angle at the intake gaskets. Sure enough, it seems the bottom of them has a bit more gap than the top. So now I have to figure out what I need to do about that. Maybe I need to do @Zeldman ’s “cut it in half and weld it” trick, but I’m hoping not. When sticking a 6-10 thou feeler gauge on the bottom side it will go through until the blue parts of the gasket surrounding the ports. So I’m not sure whether once I torque it down (after adding some permatex or spray copper gasket) it’ll seal appropriately or if I need to do something more drastic.

My 6 year old also helped me bleed the brakes. His attention span isn’t quite long enough for that to work. The fronts are done and the rears are mostly done but I think I need an adult with longer attention span to help me finish that up.

A friend of mine is going to come by tomorrow morning to help put the drivetrain in the car. I can’t wait. :)

51FC071E-B3E8-4928-9754-AC1A08E7A263.jpeg 00619B12-C6BE-423B-9B8E-C987B5EC067B.jpeg
 
Then I ground down the sides of the intake to get it to fit and checked the angle at the intake gaskets. Sure enough, it seems the bottom of them has a bit more gap than the top. So now I have to figure out what I need to do about that. Maybe I need to do @Zeldman ’s “cut it in half and weld it” trick, but I’m hoping not. When sticking a 6-10 thou feeler gauge on the bottom side it will go through until the blue parts of the gasket surrounding the ports. So I’m not sure whether once I torque it down (after adding some permatex or spray copper gasket) it’ll seal appropriately or if I need to do something more drastic.

Ok, I was wondering if you had tried torqueing the intake down and checking it. I am not the sharpest tool in the shed so the engineers that designed the intake might know something I don't.

Have you checked to see if the intake gasket is sticking up a little into the port.??

I am really interested in how the efi Weber works and what you think about it after getting it running. If I haven't mentioned it before, I like multi carbs. I am sort of thinking of putting a straight 6 chevy together with 3 deuces for my '70 chevy truck. (if I ever get time to work on it)
 
Ok, I was wondering if you had tried torqueing the intake down and checking it. I am not the sharpest tool in the shed so the engineers that designed the intake might know something I don't.

That's the hard part. The genuine Edelbrock gaskets (which are actually FelPro) have some extra sealing material (which is raised a hair) around the ports. It's been over a year since I took the intake off the original 302 with these heads (which was leaking coolant into the oil from the intake) but I seem to recall that was just a generic cheap intake. So it seems like this gasket set should theoretically handle some more off-square-ness than generic cheap (read: thin) gaskets). I've also questioned whether I should get a second set of intake gaskets, which would theoretically allow for extra off-square-ness as well. More to think on for the moment.

Have you checked to see if the intake gasket is sticking up a little into the port.??

I checked but need to check again. On the driver's side it was a bit, on the passenger side it wasn't. But then I saw the driver's side gasket wasn't seated quite right and that did help things a bit.

I am really interested in how the efi Weber works and what you think about it after getting it running. If I haven't mentioned it before, I like multi carbs. I am sort of thinking of putting a straight 6 chevy together with 3 deuces for my '70 chevy truck. (if I ever get time to work on it)

Oh believe me, Billy, I'll let you know how it works. I'm very curious myself. But first I have to make sure it doesn't leak coolant or air.
 
Looking sweet!! You need to buy a can of dykem remover for those aluminum sheets.
 
Looking sweet!! You need to buy a can of dykem remover for those aluminum sheets.

What I’ve been using is Scotch Brite pads to rough it up and mineral spirits to get the junk off before painting. We’ll see how it holds up. Nice thing is it’s just black so I can easily touch up with a rattle can if I want.
 
This morning my friend came by to help get the engine in transmission in. The engine bay is overall very spacious, but it has a few parts that are a bit different with this car vs others like a Mustang. For one, I’m running HVAC in the car and the associated box that sticks out gets close to the rear of the passenger side head. The 351 being an inch taller than the 302 makes this worse, but it still does fit.

The car also has a round pipe running left to right basically underneath the very tail of the transmission, so as you put it in you have to flatten out the engine and transmission as it goes in because you can’t let it hang down below.

The last item that caused trouble was that one of the crossmembers above the transmission tunnel hit the mid shifter. The mid shift kit is something that’s not part of what Factory Five provisions for. After looking at it for a bit we became convinced that it had to come out. So, out came the angle grinder, and off it came. Easy enough, and I can weld it back on at the appropriate point. I want to wait until further along to weld it back in. If nothing else, I want to make sure that it’s in a location that will work with cup holders that I intend to put in. :)

We couldn’t get the transmission mount on with it on the ground, so we called that a morning. Then this afternoon I messed with the lift a bit more to get it up in the air, put in the transmission mount, and tightened everything down. Engine and transmission are physically in and bolted up. I don’t need it yet, but I’m tempted to buy the driveshaft just to put it in and check that off the list since I’m ready for it.

I may spend some more time on it tonight. Lots of things I could do now that are productive.

After getting the engine in we also tried putting the intake on. It’s tight but it does fit. I am going to need to do a bit more customizing on the intake such as moving the throttle position sensor from the passenger side to the drivers side, I’ll need a 90 degree fitting for the fuel rail, and also may need to change around how some of the hoses for the HVAC are routed. I’ll figure it out, but I’m confident that I will figure it out.

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Went back out the garage to do a bit of clean-up and record a couple of videos. I felt satisfied with my work accomplished for the day so didn't feel the need to do anything further today. Plus I have to think about what I want to do next and I'm not really sure.

One thing I did notice was that I'm going to need to take some more material off of the tail shaft of the transmission. It's too close to the crossmember it sits on top of. Fortunately I can get in there with the angle grinder, I'll just have to under the two bolts for the transmission mount bushing, jack it up an inch or two, and then grind away. I should've been more liberal with the material removed. Not a big deal. So maybe I'll do that tomorrow night to finish things up for this time of working on it before my wife gets back on Tuesday and as I start thinking about the agenda for her next shift.

One thing I forgot to mention was my thoughts on the manual steering. When we got the car on the ground I had to turn the wheels a bit to steer it the right direction, so I just grabbed the steering shaft with my glove and was able to turn the wheels just fine. Now, the car is still several hundred pounds lighter than it will be when completed, but it has the engine and transmission in. If I was able to turn it that easily at the shaft without the mechanical advantage of a steering wheel, I think manual steering will be just fine. So I'm feeling good about that decision.
 
An old friend of mine messaged me today with a really interesting prospect. He bought a package deal on some parts for one of his cars that included a 42 gallon racing fuel tank for a different kind of Cobra replica. It looks like it would fit and I've asked him to make a couple of measurements to see if it would or not.

I already have a fuel tank, it's already installed, and I'm planning on doing the fuel lines the next time my wife's gone. This setup would not be able to use any of those items that I've bought already, but I also expect I could sell them to someone locally if I wanted to change course. But these race tanks are very expensive new (my friend is offering me a really good price), and if it fits, it gives me the ability to put 42 gallons of fuel in if I want, but I never have to unless I want to. That's attractive, especially if I end up deciding to do any kind of endurance racing with this car at some point. Is it actually worth it? Probably not. Is it tempting? Yes, very.
 
An old friend of mine messaged me today with a really interesting prospect. He bought a package deal on some parts for one of his cars that included a 42 gallon racing fuel tank for a different kind of Cobra replica. It looks like it would fit and I've asked him to make a couple of measurements to see if it would or not.

I already have a fuel tank, it's already installed, and I'm planning on doing the fuel lines the next time my wife's gone. This setup would not be able to use any of those items that I've bought already, but I also expect I could sell them to someone locally if I wanted to change course. But these race tanks are very expensive new (my friend is offering me a really good price), and if it fits, it gives me the ability to put 42 gallons of fuel in if I want, but I never have to unless I want to. That's attractive, especially if I end up deciding to do any kind of endurance racing with this car at some point. Is it actually worth it? Probably not. Is it tempting? Yes, very.

42 Gallons is a bunch of fuel. I'd just think about your weight concerns and what it might change if you were to put that much fuel into it. Obviously you don't have to run around with 40 gallons in the tank, but aside from a long road trip, I don't know how much use it really is. You probably wouldn't want to run it on a track with that much fuel in the rear, but I could be wrong on how much effect 100+lbs of extra fuel might have over a std 25 gallon tank (or whatever size you currently have).
 
42 Gallons is a bunch of fuel. I'd just think about your weight concerns and what it might change if you were to put that much fuel into it. Obviously you don't have to run around with 40 gallons in the tank, but aside from a long road trip, I don't know how much use it really is. You probably wouldn't want to run it on a track with that much fuel in the rear, but I could be wrong on how much affect 100+lbs of extra fuel might have over a std 25 gallon tank (or whatever size you currently have).

The current (standard) tank is 15 gallons. I really am not a huge fan of the setup. It's a standard Mustang tank with the in-tank pump and sender. I bought the tank with Walbro 255 LPH pump and fuel level sender for something like $350 with free shipping. A good deal, all brand new.

If you figure that I'll get 12-15 MPG with the Cobra (which is probably about right), 15 gallons is fine but a bit small - I would really prefer 20. Racing will obviously be less, I'd figure single digits. 42 gallons is bigger than I'd want unless I was doing endurance racing.

My gut is that it's something that is really appealing to me and would be a neat unique addition to the car. It's also completely unnecessary for my current expected use of the car. So I'm 50/50 on it.

Reality is it would add a few hundred bucks to the cost of the build by the time I paid for the tank, paid for shipping, bought the new fuel pump and other plumbing, and put it all together, and then sold my old (new) setup to someone else. If he'd told me about this a few months ago before I bought the tank it would've been a no-brainer and I definitely would've done it.
 
So, you want us all to believe you're not going to be putting your foot into it at every opportunity??? :rofl:

A lot of people get 20 with these things. My E55 (which has more horsepower) I tend to get around that same 12-15 MPG range on my commute. However I will be harder on the gas pedal in the Cobra. :D
 
The current (standard) tank is 15 gallons. I really am not a huge fan of the setup. It's a standard Mustang tank with the in-tank pump and sender. I bought the tank with Walbro 255 LPH pump and fuel level sender for something like $350 with free shipping. A good deal, all brand new.

If you figure that I'll get 12-15 MPG with the Cobra (which is probably about right), 15 gallons is fine but a bit small - I would really prefer 20. Racing will obviously be less, I'd figure single digits. 42 gallons is bigger than I'd want unless I was doing endurance racing.

My gut is that it's something that is really appealing to me and would be a neat unique addition to the car. It's also completely unnecessary for my current expected use of the car. So I'm 50/50 on it.

Reality is it would add a few hundred bucks to the cost of the build by the time I paid for the tank, paid for shipping, bought the new fuel pump and other plumbing, and put it all together, and then sold my old (new) setup to someone else. If he'd told me about this a few months ago before I bought the tank it would've been a no-brainer and I definitely would've done it.


I'm surprised the stock unit is only 15 gallons. I'd think 20 gallons would have added a better amount of range without taking up much more "trunk" space. That's at least 240+ miles of range if you are being civil with the power pedal. Maybe they thing the "standard" tank is good enough for a 30-mile run to a car show/parade and back.
 
Racing fuel tank? Is this a safety fuel cell? If so, they have limited lifespans. For racing, under most sanctioning bodies, apparently it is only 5 years from the date of manufacture, and apparently with the foam in bladder construction, they are only serviceable for 5 to 8 years.

About 3/4 to 7/8 of the way down this page:

https://fuelsafe.com/fuel-cell-facts
 
I'm surprised the stock unit is only 15 gallons. I'd think 20 gallons would have added a better amount of range without taking up much more "trunk" space. That's at least 240+ miles of range if you are being civil with the power pedal. Maybe they thing the "standard" tank is good enough for a 30-mile run to a car show/parade and back.

Keep in mind the kit utilizes stock Mustang components, including the stock fuel tank. So in those days, the Mustang had a 15.4 gallon tank. If you look at how the Mustang is designed, that provided the area for the spare tire in the trunk (at least how it looks.

The problem with how they designed the Factory Five kit is that that area (which was a spare tire in the Mustang) is just empty space in the Cobra. There are support braces that go above that area so you have to cut them out to try to make that into something usable. Just not worth it in my mind, although that is a popular mod. I don't pack heavy enough for it to matter.

Racing fuel tank? Is this a safety fuel cell? If so, they have limited lifespans. For racing, under most sanctioning bodies, apparently it is only 5 years from the date of manufacture, and apparently with the foam in bladder construction, they are only serviceable for 5 to 8 years.

About 3/4 to 7/8 of the way down this page:

https://fuelsafe.com/fuel-cell-facts

Now, that is actually an interesting question and I'm not sure I know the answer. I'm also not sure if this qualifies as a safety fuel cell or not, if it's foam filled, etc. I am 99% certain it's more than 5-8 years old. So that actually might answer the question for me.
 
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