DuPuis Family Cobra Build

One difference between my "thinking about" and Ted's "thinking about" is my projects are 2-3 years out and still in the "thinking about" stage, whereas Ted goes from "thinking about" to "up to my eyeballs in" within 24 hours ... :D
 
gkainz said:
One difference between my "thinking about" and Ted's "thinking about" is my projects are 2-3 years out and still in the "thinking about" stage, whereas Ted goes from "thinking about" to "up to my eyeballs in" within 24 hours ... :D
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You'd be surprised. A lot of these things mull about in my head for years before I talk about them. By the time I talk about something, I'm pretty much ready to pull the trigger, it's just a question of what specifics I decide on, and looking for help/input there. PoA is an excellent resource there.
 
FormerHangie said:
It's because you have a long repressed desire to be a gearhead. My advice is to embrace it and start thinking about a project.
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Must not buy WRX donor car!
Must not buy WRX donor car!
Must not buy WRX donor car!
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weilke said:
Must not buy WRX donor car!
Must not buy WRX donor car!
Must not buy WRX donor car!
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DON'T buy a donor car. Instead, call these guys: http://www.verycoolparts.com/donors.htm and have them send you a donor kit. You get all the pieces you need and don't have to deal with the rest of the car.

Everskyward said:
Same here. But I'm not drawn to IT threads in the same manner.
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As an almost 40 year IT veteran, I completely understand. My own family has no idea what I do for a living. The joke is that I'm a "transponster", after the guess that the Rachel character from "Friends" made when asked what the Chandler character did for a living.
 
Honestly, Ted, what I would do at this point is completely disassemble the block and heads, decide if you want to keep that manifold or go with a DP, throw it into the back of your new pickup (don't need the trailer) and bring the whole shebang to a good machine shop for an evaluation. All the geometry issues can be machined out by somebody who knows what they're doing, but only if there's enough metal remaining in the right places. I mean, you want to put aluminum heads on an iron block, which is fine, but you need to see the deck surface of the block has the correct surface texture or the head gaskets won't seal. You want to up the compression, but obviously not with the cylinders yhe way they are. Only a couple of many issues.
You can spend a lot of time on the phone with the tech folks, but an experienced engine shop will tell you if you have something to work with. Probably won't cost you but a couple hours of labor for the opinion. Then you can decide whether you want to invest in this thing or not. This engine obviously isn't a virgin.
Otherwise, buy a short-block, reuse what you can and be done with it.
 
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Chip Sylverne said:
Honestly, Ted, what I would do at this point is completely disassemble the block and heads, decide if you want to keep that manifold or go with a DP, throw it into the back of your new pickup (don't need the trailer) and bring the whole shebang to a good machine shop for an evaluation. All the geometry issues can be machined out by somebody who knows what they're doing, but only if there's enough metal remaining in the right places. I mean, you want to put aluminum heads on an iron block, which is fine, but you need to see the deck surface of the block has the correct surface texture or the head gaskets won't seal. Only one of many issues.
You can spend a lot of time on the phone with the tech folks, but an experienced engine shop will tell you if you have something to work with. Probably won't cost you but a couple hours of labor for the opinion. Then you can decide whether you want to invest in this thing or not. This engine obviously isn't a virgin.
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Agreed, Chip, and that was what I was going to do. My real point in talking to the tech support folks is also to figure out the right combination of other parts. Recommendation on cam, for instance. I'll probably take it to the machine shop next week.
 
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Please tell me that oil pickup is not upside down....
 
Ted DuPuis said:
I could tell you that, but I don't want to lie.
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I was in the racing business for a number of years and I have seen some things that just baffle me, and this is one of them.

The top one was the guy that drove in with his 1968 Cougar with a mechanical fuel injected 302 that had a slight vibration in it. First thing we found was that the heads had been shaved enough that the intake didn't fit properly. We cut the intake in half lengthwise to fit it to the engine, then welded it back together. That stopped the vacuum leak but didn't stop the vibration. So we check the rocker arms for anything not fitting well, push rod length, valve spring height, valve stem length, even the cam bearing clearances. Finally we pulled the heads off........ WOW..!!!!

The top of the pistons looked like a waffle. The guy that put the engine together took a grinder and worked over the pistons thinking that the waffle pattern design would atomize the fuel better.....

A quick call to Iskenderian to suggest a cam, new set of pistons and that thing would fly. (for a small block Ford)
 
Zeldman said:
I was in the racing business for a number of years and I have seen some things that just baffle me, and this is one of them.

The top one was the guy that drove in with his 1968 Cougar with a mechanical fuel injected 302 that had a slight vibration in it. First thing we found was that the heads had been shaved enough that the intake didn't fit properly. We cut the intake in half lengthwise to fit it to the engine, then welded it back together. That stopped the vacuum leak but didn't stop the vibration. So we check the rocker arms for anything not fitting well, push rod length, valve spring height, valve stem length, even the cam bearing clearances. Finally we pulled the heads off........ WOW..!!!!

The top of the pistons looked like a waffle. The guy that put the engine together took a grinder and worked over the pistons thinking that the waffle pattern design would atomize the fuel better.....

A quick call to Iskenderian to suggest a cam, new set of pistons and that thing would fly. (for a small block Ford)
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I agree that Isky would have good suggestions. I remember talking to Ed probably 15 years ago about cam suggestions for the Jag V12 I was working on at the time.

Fortunately these guys were "inventive", but not as invetive as that guy. And also fortunately, he didn't get it to run.

One thing I'm debating on is whether to try to get this Accel distributor (brand new) to work or buy an MSD-whatever. I like MSD stuff much better than Accel, so that's probably my answer.

The oil pan, I'm going to see if that will work once I get the car together.
 
Ted DuPuis said:
I agree that Isky would have good suggestions. I remember talking to Ed probably 15 years ago about cam suggestions for the Jag V12 I was working on at the time.

Fortunately these guys were "inventive", but not as invetive as that guy. And also fortunately, he didn't get it to run.

One thing I'm debating on is whether to try to get this Accel distributor (brand new) to work or buy an MSD-whatever. I like MSD stuff much better than Accel, so that's probably my answer.

The oil pan, I'm going to see if that will work once I get the car together.
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Ed was a good guy to be friends with, for sure.

MSD. I would have a MSD unit on my diesel if I could just figure how to make it work...:lol::lol:
 
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Zeldman said:
MSD. I would have a MSD unit on my diesel if I could just figure how to make it work...:lol::lol:
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That's my thought as well. I figure I'll put this thing up for sale.
 
You could run the Accel, though the vacuum advance parts are kind of cheap. What I did was run a Duraspark II distributor, a GM 4 prong module and any old high output E-core coil, in this case from a Ford pickup. The "High Performance" Accel module is in fact a GM 4 prong. Tune your advance by changing out the advance springs. I like MSD products, I have a setup in my Jeep because the whole deal has a huge heat sink and is hermetically sealed, but this ignition setup performs just as well for fraction of the price of the MSD box alone. As a matter of fact I'm pretty sure the MSD uses Duraspark innards. I think the dizzy, module and coil came to $100 total. Spend the money you save on machine work.

Got the idea from this guy.
http://www.junkyardgenius.com/ignition/jeep/HEI01.html
 
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Accel vs MSD- I’m cheap, so I’d use what I had and tinker/swap later. Not likely going to see any performance difference. Same with water pump. But I’m not you...

Those of us that contemplate spending money but take our sweet time opening the billfold love this thread. I’m living vicariously through your wallet...
 
Pistons out.

Guesses for tonight’s mystery? :D
 
Ted DuPuis said:
Pistons out.

Guesses for tonight’s mystery? :D
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6 left side pistons and 2 right side..???

4 are 040 over and 4 are 060 over..??? (or some variation of)

They are actually chevy pistons..??

The wrist pins are PVC..???
 
Zeldman said:
6 left side pistons and 2 right side..???

4 are 040 over and 4 are 060 over..??? (or some variation of)

They are actually chevy pistons..??

The wrist pins are PVC..???
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Chevy 350 crank cut and rewelded for fitment into the 302?


Sent from my iPhone using Tapatalk
 
FormerHangie said:
DON'T buy a donor car. Instead, call these guys: http://www.verycoolparts.com/donors.htm and have them send you a donor kit. You get all the pieces you need and don't have to deal with the rest of the car.
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Disassembling a car, cleaning and overhauling the parts would be half the fun. I am in the fire department, the rest of the carcass will be minced meat at the end of drill night.
 
weilke said:
Disassembling a car, cleaning and overhauling the parts would be half the fun. I am in the fire department, the rest of the carcass will be minced meat at the end of drill night.
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OK, there you go, even more reason to find a donor WRX.
 
The engine is fully apart! So here's what I've found.

1) The bearing are shot. Varying levels of shot, but definitely shot. Now, given how screwed up the oil pump was, it's possible that this occurred during extended cranking and screwing around trying to make it run.

2) The pistons also have a good amount of the friction coating removed, varying degrees of scuffing. Again, could've been a lot of cranking without oil, but it could also be that the bottom end was older. The heads are definitely not highly used, though, and the oil pump looks brand new. This remains a mystery.

3) I need to look closer at the crank for identification. The rods are C3AE which are either Boss 302 or 289 connecting rods, depending. This somewhat makes me wonder if it doesn't have a 289 crank in it. Need to look closer and see.

4) The camshaft definitely has a wear pattern on it. I had a hard time finding anything useful for casting information. I found a couple numbers stamped on it but I have no idea if this cam is aftermarket or some stock version.

5) The timing chain is brand new.

6) Crankshaft looks good

7) Bores look ok. No cross hatching evident as I previously noted. One of them has a single but significant score mark on it towards the bottom.

Obviously I first have to make sure if the crank is a 302 and not a 289 before I consider reusing it, and the machine shop is going to have to tell me whether the block has the potential to get bored to 60 over. Also have to confirm rod length to see if they're reusable. But I have a suspicion that this engine may be a 289. What I'm thinking may have happened is the guy found this block, knowing it was desirable, and then bought the parts to bolt on. It'd fit the rest of the story.

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FrankenMotor.

A fascinating journey - keep 'em coming!
 
When I was high school age, I went in on a purchase of a Datsun pickup truck with another guy with the idea that we were going to fix it up, repaint it, and sell it. It was cheap. Turns out that it had a loud knock, and it overheated on the drive home. I had some time on my hands, and access to the base auto shop, so I took on the task of fixing the engine.

Turns out someone tried to rebuild the motor but botched it. One of the rod bearings was missing, and the head gasket had been installed upside down, blocking the coolant passages. I took the crankshaft and rods to a machine shop, and they were able to salvage them by knurling them, replaced all the bearings, and reassembled the motor with a new gasket kit, and it ran great. In fact, the other guy just decided to buy out my half and keep it. It was a fun little project.
 
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455 Bravo Uniform said:
Accel vs MSD- I’m cheap, so I’d use what I had and tinker/swap later. Not likely going to see any performance difference. Same with water pump. But I’m not you...

Those of us that contemplate spending money but take our sweet time opening the billfold love this thread. I’m living vicariously through your wallet...
Click to expand...

My issue with the Accel items is that I've had them just not work or provide really weird failure modes. Now, that could just be my luck, but MSD makes better stuff. There are some things I like messing with, but crappy parts aren't one of them. I'll think about it.

Some things are worth spending money on, some aren't.
 
Sac Arrow said:
When I was high school age, I went in on a purchase of a Datsun pickup truck with another guy with the idea that we were going to fix it up, repaint it, and sell it. It was cheap. Turns out that it had a loud knock, and it overheated on the drive home. I had some time on my hands, and access to the base auto shop, so I took on the task of fixing the engine.

Turns out someone tried to rebuild the motor but botched it. One of the rod bearings was missing, and the head gasket had been installed upside down, blocking the coolant passages. I took the crankshaft and rods to a machine shop, and they were able to salvage them by knurling them, replaced all the bearings, and reassembled the motor with a new gasket kit, and it ran great. In fact, the other guy just decided to buy out my half and keep it. It was a fun little project.
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Something I've really enjoyed with this so far is just how simple taking everything apart is. I'm used to cars that are pretty complicated and you have to take a lot off just to get at what you want to actually do. The goal with the Cobra is easy/simple.
 
Again.... just wow.

The one picture of the bore it appears to have been honed, but by someone not knowledgeable to honing.

The one piston appears to have a do it yourself friction coating, again by someone that doesn't know how to do it.

The scoring on the cylinder wall shows it may have been put together dry and did not prime the oil pump until after attempting to start it. Might pull the bottom plate off the oil pump and check the insides.

Were the timing marks aligned correctly on the timing chain set.??
 
I'd put money on that it was assembled dry. When i was in HS I rebuilt a Fiat 1200 from the crank up. Made the rookie mistake of not packing the oil pump with Vaseline before installation. Used plenty of assembly lube on the bearings, and lubed the pistons though. Cranked hell out of that thing trying to get oil pressure before firing it up. Realized the mistake, pulled the pan, a couple bearing caps and got a good look at the cyl walls. No scuffing, bearings were still a nice, dull gray.
If he cranked that thing enough to wear the bearings and walls like that and it wasnt dry, I want to know what starter he was using.
I agree, that looks like a bad DIY bottle-brush hone job.
 
Zeldman said:
Again.... just wow.

The one picture of the bore it appears to have been honed, but by someone not knowledgeable to honing.

The one piston appears to have a do it yourself friction coating, again by someone that doesn't know how to do it.

The scoring on the cylinder wall shows it may have been put together dry and did not prime the oil pump until after attempting to start it. Might pull the bottom plate off the oil pump and check the insides.

Were the timing marks aligned correctly on the timing chain set.??
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I'd had that same thought about wondering if someone honed it but didn't know how to do so properly. Like someone who bought one of those drill hones but then just let it sit in one spot instead of going up and down rapidly to get a cross hatch in. I really have no idea.

I agree with you on the oil pump not getting primed, and that would also explain why the bearings look so shot and why there was zero evidence of oil in the valvetrain. And I mean zero, zilch, nada. Just nothing. So my guess is the damage happened in all that cranking.

The friction coating on the piston isn't DIY. The part number on the piston matches SpeedPro hypereutectic pistons which have that coating. It's a factory coating. However without oil it would rub off quickly. They probably didn't have everything properly cleaned, hence the issue at the bottom end of the bore. What a cluster.

The oil pump looks brand new, but I'm thinking I'll just replace it with a new high volume in order to be thorough. But I might check the inner workings first just to see.

I forgot to check the timing marks before pulling the timing chain, so no idea if those were correct or not. But the timing chain was brand new, no doubt.

My guess is the guy didn't want to spend the money at the machine shop. I am planning on calling up Crane and Edelbrock with a few questions on those parts for a sanity check, but really I need to take this block to the machine shop and come up with plans from there.
 
Chip Sylverne said:
I'd put money on that it was assembled dry. When i was in HS I rebuilt a Fiat 1200 from the crank up. Made the rookie mistake of not packing the oil pump with Vaseline before installation. Used plenty of assembly lube on the bearings, and lubed the pistons though. Cranked hell out of that thing trying to get oil pressure before firing it up. Realized the mistake, pulled the pan, a couple bearing caps and got a good look at the cyl walls. No scuffing, bearings were still a nice, dull gray.
If he cranked that thing enough to wear the bearings and walls like that and it wasnt dry, I want to know what starter he was using.
I agree, that looks like a bad DIY bottle-brush hone job.
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Packing the oil pump with Vaseline? Why wouldn't you just prime it with oil?
 
SoonerAviator said:
Packing the oil pump with Vaseline? Why wouldn't you just prime it with oil?
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Don't have to worry about liquid oil running out, or spilling, or the pump getting turned with nothing in the sump. Pack the gears with vaseline and it creates enough suction to pull the oil, then just liquifies.
The other thing I learned since then? A 1/2" drive drill and a long piece of hex stock through the distributor hole to spin the pump is the way to get pre-start pressure.
 
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Chip Sylverne said:
I'd put money on that it was assembled dry. When i was in HS I rebuilt a Fiat 1200 from the crank up. Made the rookie mistake of not packing the oil pump with Vaseline before installation. Used plenty of assembly lube on the bearings, and lubed the pistons though. Cranked hell out of that thing trying to get oil pressure before firing it up. Realized the mistake, pulled the pan, a couple bearing caps and got a good look at the cyl walls. No scuffing, bearings were still a nice, dull gray.
If he cranked that thing enough to wear the bearings and walls like that and it wasnt dry, I want to know what starter he was using.
I agree, that looks like a bad DIY bottle-brush hone job.
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Interesting, I'd never heard of that before. Something to keep in mind.

It's also possible that the bottom end is older and he did a refresh of some sort on it at some point. Or he'd gotten the engine running at some point and damaged it, and then the guy who bought the engine and put it in the Mustang never succeeded in getting it running in that car.

Who knows, I sure don't.

I called Edelbrock to tell them about what I found on this. The guy said that my theory of the intake gaskets being put on improperly and leaking coolant is one of the most common things they see, and said that was one of the most likely causes. From all the evidence I've found thus far, I'm thinking that's the cause of the coolant leaks that resulted in the coolant in the oil, explains the coolant level in the radiator being at the level it was, etc. Still need to make sure the block and heads aren't cracked.

I need to have those looked at first, and once I confirm they're good, the next question I view is which cam and springs to use. But first, need to make sure the base short block + heads are good.

Well, and decide if I want to keep this crank and rods...
 
I'm beginning to think that I could have done a better job on that engine than whoever did that.
 
Ted DuPuis said:
Depends. What's the limit on your credit card?

And if you can PM me the number, CCV, and expiration date, that would help to prove your theory.
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I'll check with my guy in Russia - he keeps sending me emails asking the same thing.

My brother, a GM mechanic, sends pix of some of the things he sees. He's at a dealer, though, so he doesn't generally see too much DIY shennanigans. Mosty it's deferred maintenance, like 70k miles between oil changes and the owner complains the car won't start.
 
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Matthew said:
My brother, a GM mechanic, sends pix of some of the things he sees. He's at a dealer, though, so he doesn't generally see too much DIY shennanigans. Mosty it's deferred maintenance, like 70k miles between oil changes and the owner complains the car won't start.
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That I would completely believe. The number of people who simply fail to change oil is astounding to me, and always has been.

When I was a mechanic our customers were primarily shop customers. So you'd see some oddball stuff come in, but in a lot of cases we'd simply refuse to work on it. Usually the people who brought something in after they broke it were the sorts who couldn't afford to have it fixed right in the first place.

It's sort of like why an aircraft that was on 135 is considered a positive. Is it a guarantee that it was maintained properly? No. But there's generally more consistency with MX performed under 135 than under 91, even though it's typically all done by an A&P/shop.

I'll probably call the machine shop on Monday and see about bringing the block by to them early next week to look at. That's the first question before I make any other decisions. I got a new battery for my caliper, so I'm going to take some measurements tonight.
 
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