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1968 Coronet 500 Project

I am kind of the same way Jim. I need my bumpers rechromed and a 6 Pack hood but no rush and it is boring not having the car apart. It is so bad I just cleaned my garage lol. I'll give you a head start on that big block and give you the set of 906 heads and 440 intake I have in my garage. I'm thinking of pitching them.

Come clean my garage! No thanks I don't have room for what I have now and the oldest is wanting a car...... Sell the GTX to Bill and get something new :)
 
Took the Coronet to the first "real" show Saturday in Sierra Vista. I think they said 274 entries. First one that had about as many trailers in the parking lots as cars :).... I found myself starting to defend the decision to keep the 318 with a local club member who was, of all things, a Chevy owner and his car was close to mine .... WTF..... I do like the smaller shows with folks that seem to enjoy the cars and work done for what it is and do not need to justify why they spent thousands and thousands of dollars on their (fill in the blank) 500HP+ engine that they need to trailer in because it is too far to drive it.....

Overheard another guy saying to his buddy he was "shocked that it had a 318"... Of course there were lots who just said it was a beautiful car but for some reason those are not the ones that say with me....
 
Last couple shows I went to I also tended to shy away from SB's; but then you start at workmanship,etc., and ya kinda say "hey, it looks pretty good" AND it's his car. Cubes don't always make it better.
 
Last couple shows I went to I also tended to shy away from SB's; but then you start at workmanship,etc., and ya kinda say "hey, it looks pretty good" AND it's his car. Cubes don't always make it better.

Yea, I just don't understand that. I saw my first Hemi Coronet a few months ago. I went and looked at it for all of about 30 seconds and walked away disappointed. I thought I should have been feeling great. It was all original and unrestored (bought that way). It was that point that I realized what I enjoy about car shows is looking at the craftsmanship and heart the owner puts into their car not what it actually is. The owners that love their cars is obvious.
 
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I agree with you when it comes to trailer queens and Hemi cars; the Hemi may have been the legend at the 1/4 mile and big oval, but many of my friends claim it is the most temperamental motor for street use. Like you I prefer the car shows that have some focus on the 'average guys' and hobbyist. Generally, the car club shows are not laden with trailer queens and I've enjoyed meeting new people at these car shows as well.
 
Jim I kinda disagree, the first hemi I saw was a guy came in for a fill up & said "check the oil". Plain Jane white Ply/Dodge, I was probably only 15 at the time, but I knew what I was seeing& touching!
 
Jim I kinda disagree, the first hemi I saw was a guy came in for a fill up & said "check the oil". Plain Jane white Ply/Dodge, I was probably only 15 at the time, but I knew what I was seeing& touching!

There is nothing wrong with that. Everyone has their own reasons for enjoying a hobby, what they like and what makes them enjoy it. Just don't try to argue with someone it should have done in a way that they would enjoy it.
 
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Tinkered around with some Engine Building Software. I have been curious as it if what I did to the 318 was good bad or indifferent. In my mind I think it is not a slouch. It is does not have spin the tires off power but when you get on it she will down shift and easily accelerate that 2 ton beast.

Included was a Stock 275 HP 340/383/440 so I scaled off that model to create what I think the stock 318 was and what my engine build is. The numbers are a bit higher than what I think they would be as the software assumes you are always using some sort of header. The stock 318 tops out at about 190HP which I have always guessed it was around 170-180 since the known later 8:1 compression engines that were reported in the standard test method from '71 on shows them in the 155HP range and the '68 318 was 9.2:1. The model does show about a 20HP gain from the compression difference so I am close. The cam makes a big difference and I have no idea of the durations of the factory cam so the are closer to what my cam I installed is. I do have the correct lift though....

Horsepower Calculated.jpg


You can see above I made a huge difference against that stock 318 so I think my seat of the pants is correct. The torque is a lot flatter. For comparison the higher torque and HP lines are a stock 275HP 340 from 1968. It is clear to get low end grunt there is no replacement for displacement, the only way to get those numbers up is to get more cubes.

So next I wanted to see what would happen if I had gone with a higher compression ratio on my build. It already has a bit of a detonation problem with the 8:1 pistons. I cranked it up to 9.2:1 and it actually is matching the 340 up to the point where I think the smaller valves are just not able to let in anymore air/fuel mixture.


Horsepower Higher Compression.jpg


Then for fun here is how the Coronet stacks up with a stock 1968 383 and 440.

HorsePower Mopar.jpg


Interesting spinning that big 440 mass the HP drops off way faster than the 383 but man look at that torque hump in the 440 right where you want it!

I am going to say I am in the 250HP with 320 Ft/Lbs of Torque range. Seems about right for how it runs.
 
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Got my distributor goodies from FBO. New springs and a lock out so I can run more initial timing.

New medium springs installed, old ones are on the top.

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Lockout plate installed for 18 degrees of mechanical advance max.

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Put the clip back in for the rotor and we are done.

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16 Degrees advanced suggested by Don is pings. That is 16 + 18 for a max of 34 degrees. The vacuum is set for 30 degrees on a constant vacuum per Don. Have some questions in to him. The factor plate says 19R on it (19 degrees?)
 
Well shazbot, I think the markings on the FBO plate are off by a factor of 2.... The instructions says it is a direct read but I am getting 52 degrees of initial + mechanical advance with 16 initial... that = (18*2) + 16..... Time to call Don at FBO
 
Set it to 12 assuming 16 + 2*12 = 40. The other option was 16 + 2*14 = 44 which is what it should be. The daughter took over the garage for her hobby so I can't start it and see if it works better but if you now turn twist it by hand it locks out just a bit over 1/2 of what it did.
 
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Finally! I set it to the 10 position, 16 + 10*2 = 26 but it measured 34 total advance. Probably the points are adding a bit! Wow, what a difference. It actually unloads the torsion bars when and lurches ahead when it down shifts into second when rolling at around 55. If you don't downshift it still pushed you back in the seat slightly. Much different car! Now I can start tuning the EFI and see if some the the mysterious setting that I needed to set can be put back to normal values! Also took off the front grill trim and adjusted the headlights while tooling around after dark.
 
Now that I have this figured out I called Don at FBO. He told me that the vacuum advance was too much and a trick to fix it. I tried it and failed so I came up with something more precise and very easy..

You need to limit the travel of the arm that gets sucked back into the canister...

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Compressed you see the cross bar just hits the back of the can as a stop.

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So what I did was get one of my sheets of 0.015 brass and cut some shims.

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They are flexible and you have to bend them to get them in but once in they can't escape and now I have 0.015" adjustment.

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3 shims took it from about 24 degrees to about 12.

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Won't tell you how fast I can R&R that distributor these days. Took me exactly 100 seconds the last time to get it out :)

I now have it set for 18 degrees initial + 18 degrees mechanical + 12 vacuum give me 48 cruising. It should be closer to 50-52 but I am going to see how much initial+mechanical I can run first before detonation. The 8:1 compression should allow me to run a lot of advance. I am out of adjustment on the BFO plate and the next one is locked down with 0 degrees. The medium FBO springs start in at about 1800 RPM and are fully engaged at about 2800 RPM. The engine likes all this advance. When I stomp it at speed it downshifts with a slam and it pushes you back in the seat a bit! It is a different car to say the least. It also looks like the fuel economy is higher plus I was able to lean out the Air Fuel Ratio in the FiTech to closer to 14.7:1
 
Looks like you are getting it close. Messing with this stuff is how we all learn about this stuff.

I don't know if I ever asked you, but do you ever make it down to Patagonia, specifically the Wagon Wheel?
 
The kids go to school in Patagonia, we are there all the time. I have not been to the Wagon Wheel in decades. We go to Velvet Elvis Pizza, Wild Horse (was Home Base) and Gathering Grounds mostly.
 
The kids go to school in Patagonia, we are there all the time. I have not been to the Wagon Wheel in decades. We go to Velvet Elvis Pizza, Wild Horse (was Home Base) and Gathering Grounds mostly.
Haha. My cousin Jerry use to own it now he works there part time after selling it. Still lives down there. Old white haired guy, moustache, funny as hell.
 
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