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'68 Coronet project EFI/4 speed conversion up and running!

On your fuel level gauge issue.... You have the Holley tank which I'm guessing means means you have a five bolt style sending unit?

If so and you have this style sending unit...

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I've had about zero luck getting a decent reading from that sender....

So when I saw this style sender was available I gave it a try.... Right out of the box it was a night & day difference... Since then I've installed three more of the tube style senders & every time it's been a positive experience....
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You need to know your tank depth & the Ohm range...


Oh, BTW your car looks great & I feel your frustration.... BTDT...
 
Thanks! I have not seen one of those senders. Next time I drop the tank I’ll have to remember to look into one.

The fuel gauge mostly works. I’ve learned that it always reads higher than it is. The truest reading shows after hard acceleration - the gauge pointer drops to a low point momentarily and comes back up. The low point is the correct level.
 
On your fuel level gauge issue.... You have the Holley tank which I'm guessing means means you have a five bolt style sending unit?

If so and you have this style sending unit...

View attachment 1424193

I've had about zero luck getting a decent reading from that sender....

So when I saw this style sender was available I gave it a try.... Right out of the box it was a night & day difference... Since then I've installed three more of the tube style senders & every time it's been a positive experience....
View attachment 1424194


[/URL]


You need to know your tank depth & the Ohm range...


Oh, BTW your car looks great & I feel your frustration.... BTDT...
I just ordered one of these for my Charger build, good to heat that they seem to work.
 
OK, so I got the dipstick tube from my friend today and thankfully managed to get it installed properly. What a hassle.
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It wasn't used like he said but "NOS" which of course meant he wanted more for it. His definition of NOS is a little loose too since it wasn't "1968 NOS" but rather from a dealer when these were still available back in 2003. I actually worked at the dealer where it was purchased from for a year and the parts guy was our mutual friend. I was a little surprised that he didn't specify it was a more recent part to begin with because he is usually very clear about stuff but it's fine, it worked out in the end. He's a kooky guy that can recite part numbers off the top of his head but despite his rain man aptitude for parts everyone respects his unmatched knowledge. Besides, he just happens to always have what I need. Gotta take the good with the bad as they say.

This particular tube is from a later model car, like '70-'71. The mounting tab was in the wrong place for my application, I think this one is supposed to mount to the outside of the exhaust manifold and not the motor mount bracket. The tube is also much straighter than the '68-'70 ones which have more of an S shape. This later one seems to work a little better with the headers though.

One thing I learned today about installing these indicator tubes is that you really need to grind the bottom down so it's very thin. Even though I did file the previous one down, I didn't go far enough. This time I started with emery paper and kept test fitting to see if it would go. The emery paper was taking too long so I went to 80 grit sanding rolls on my air grinder which did the trick. The emery paper was closer to a polish than material removal. Once it's thin enough it conforms to the hole and is much easier to get in. It was sealed with RTV.

It was a hassle to get the mounting tab in the right spot. I cut it off from the original location (which was too high up) on the flat side and then re-shaped it with a hammer and dolly to conform to the tubing. Came out OK. The mount bolt is close to the tube so it had to be pried over while knocking the bolt through with a drift. PITA. I have to either tack weld or braze the tab on then this stupid dipstick ordeal will be done and I can button things up.

Here's the tab that was cut and re-used.
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More to come.
 
Well, so far so good on all the recent repairs/updates to this car - oil pan rail is dry and the exhaust leaks seem to be gone. The dipstick tube is in and seems to be OK. I have not driven it for any great length of time yet so that will be the real test but it's definitely running smoother than before. Much less noise/harshness from the rear end now too now that everything has been tightened up again. Still have some wiring-related things to take care of as well but the drivability is mostly back to normal.

Before I took this picture, the drain plug was seeping and I could feel my blood pressure starting to rise. If I found the pan to be leaking again, I would have set the car on fire. Snugged the plug up and its dry - for now. No fire.
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In addition to the oil pan, dipstick and exhaust, I made and installed new spark plug wires and replaced the plugs due to the previous over-rich A/F condition. The plugs were not that old but they were toast - couple were completely black, one or two were lean...time for new ones. I used Autolite 85 this time gapped to .035". They have a longer insulator than the Bosch ones I replaced so they stick out a little farther. On the first test drive three wires came off and I thought the car was going to shake itself to bits. One was laying on the steering shaft and I could hear it arcing to it. Before I knew what it was though, it sounded like another exhaust leak. Demoralized, I limped it the car into the garage and prepared for the worst but then saw the little arc flash. Whew! I never felt so relieved to see a wire had fallen off. Weird that three came off but easy fix, just stuck 'em back on. I just failed to get the boots all the way down on the longer insulators. All god now.

For the wires I always use Taylor cut-to-fit 8MM with the 135º boots. I got some better looms and separators this time as well to help keep them off the header tubes. I also used some DEI-brand heat sleeves to slide over the wires where they are close to the tubes in case they do touch the exhaust.

Yes, the number one spark plug tower is on the passenger side... I considered re-setting it so it's on the driver's side but didn't feel like getting involved with that.
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Driver's side. Note the new dipstick - no paint as per factory installation. Had to bend it slightly to keep it off the #1 tube. I believe this one is for a '71-up big block because the '68-'70 one I had previously was completely different. I like this one better.
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Passenger side plug wire routing. Note the home-brew valve cover bolt stand-off on the left to keep the #8 wire off the header. It's a short piece of 3/8" tubing with an Adel clamp. Corny and cheap but it works.
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Couple wiring-related things under the dash to take care of next which will require dropping the column and taking out the instrument panel. I'm not looking forward to that job but it's got to be done, I want this car to be 100%. BTW, I looked at the Dakota Digital standard dash set again and was shocked at how much it went up since last year. I could be wrong but when I first saw them they were nowhere near that much, I had it in my head they were around $1,100 or so. Too much now.

Last - the current EFI tune basically had to be re-set so it wouldn't continue to use the learn tables that were compensating for the rich condition. It will take a while to fill the table in again but I don't really have to fix anything per-se, just have to drive it and let it re-learn. Looking forward to getting back to driving this car regularly when the weather gets warmer. Hopefully all this stuff I did stays good for the foreseeable future.

More to come.
 
I looked at the Dakota Digital standard dash set again and was shocked at how much it went up since last year. I could be wrong but when I first saw them they were nowhere near that much, I had it in my head they were around $1,100 or so.
Only $1,095 for the VHX... 1970 Rallye Guage layout. I can definitely compare that one. They were $975 or so for years, so not a big hike there. I'm surprised the "standard" is more, but I never shopped for that one.
I actually bought the VHX setup at a great price and held on to it for a few years, but right when I was going to have it installed along with a LOT of other work done, DD came out with the RTX gauge system and I HAD to have that one!
 
No way to justify the cost of that DD standard gauge panel, it's out of line. Even the prior $1,100 was ridiculous but I was considering it anyway. Guess I missed my chance though because there's no way I'm spending $1,800 on it now. I don't have a Rallye dash so the cheaper one is not an option.

There are things I don't like about the standard one anyway, namely the block displays on either side of the speedo. I wouldn't want them 'on' all the time, even if you can customize what they show. To me it screams cheap, primitive electronics and 100% reminds me of the '88 Regal I inherited from my grandma in the early '90s. No thanks.

Also, the bezel surround they provide I believe is from a Road Runner and likely wouldn't work for my dash. The Coronet 440 models have a long trim strip that goes all the way across the whole dash including the instrument panel. I would have to either had to cut that piece or remove it but then the gaps between the pad and face would show. Again, not so much.

The digital gauges I have now were $625 for all 6 and I got to customize them to my liking. I'm happy with them. Only thing I miss is a working odometer because the 2 5/8" speedo face is too small to fit it but I'm used to it now.

I've posted this previously but it's cool so here it is again.
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You have to compare against the price of resto on an OEM set which is not cheap. Or buying the knockoffs
 
You have to compare against the price of resto on an OEM set which is not cheap. Or buying the knockoffs
I'll take your word on that since I have not looked into getting OE gauges restored myself. I still maintain $2K for a set of gauges is too much but I get what you're saying. If you want nice stuff you gotta pay the piper.

Regardless of cost, the thing I really like about digital gauges is the LED lighting, it makes a huge difference. I can't say from first hand expereince whether this is fact or not but it's hard to see how even newly-restored factory gauges with incandescent bulbs could offer the same level of illumination.
 
One of MANY features I like about the RTX gauge system is the color options. I had chosen the red backlight for the VHX setup I had that I sold because of red not having a negative impact on night vision.
With the spectrum of programmable colors available in the RTX gauges, including different day (lights off) and night modes, I have a bolder, more colorful daytime combo of needle and backlight and the mostly red night (lights on) mode.
I also have made use of a few DD modules to provide data not only on the LCD display but also a remote smartphone or tablet. With a tuning issue I need to address, I need to take advantage of the "remote dash" capabilities.
I have already benefited from the individual gauge warning light and audible alarm.
Still, the visual beauty of what appears to be a brand new factory gauge set is almost worth the cost by itself.
 
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Gotta get out there and drive 'em boys. Perfect day to enjoy the commute yesterday. Yes, unfortunately Premium is still over $4.00/gallon here, what can you do.

So as alluded to, I drove in to work yesterday (40 min. one way) and have to say the car is running very well right now. For those following along, fixing the exhaust leaks has made a huge impact on drivability. It's amazing how the tuning responds when everything is up to snuff.

To get it where it is now required some software adjustments for sure. After the exhaust was sealed up the "learn table" had to be reset to accommodate the improved conditions. Since the leaks were sucking extra air, the ECU was compensating by throwing fuel at every part of the fuel curve. Some of the rich condition was also due to previous tuning choices I had made not realizing how much of an impact the exhaust leaks were having. In addtion to some slight timing table adjustments everything was leaned out across the board. You chose a target AFR and the ECU supplies the appropriate amount of fuel for a given point. Prior to the exhaust repairs, the AFR was reading two points rich no matter what I did. No bueno! It's hitting the targets now so whatever I did worked OK.

After doing this for a couple years now, I'm finally getting a decent handle on the software. During the "re-tuning" process I used the laptop to make "live" changes which was cool as it responds right there. I had tried that a few times before but admit I did not really know what I was doing and it seemed like nothing was happening. Chalk it up to experience I guess. Or maybe a sealed exhaust system.

As I've said a few times here, this 383 is not a world beater by any stretch. In peak condition I think it's probably around a 300 hp engine. The factory claimed 335 hp with the "Roadrunner" cam (which is what's in my engine) but I have my doubts about that. Even with headers, digital spark, slightly milled heads and a basic aluminum intake I seriously doubt it's making much past 300. This is proven by the fact that the fuel table says it's never using much more than 125-130lbs of fuel. Using that as a rough guide to estimate power, that's barely cracking 250. It gets close to 150lbs when it's revved over 4K rpm but sadly that's a rare thing with unported, '70s production iron heads, 3.23 gears and a small hydraulic cam.

Couple other notes - softening up the rear shocks one click was the right move. It's still a little on the harsh side but noticeably easier going. Even for a big, heavy car it sticks to the road very well. I'd even go so far as to say it handles as well as or better than my '17 Ram. I've even tried to break it loose a few times (within reason, public roads and all) but almost can't. Currently the front shocks are slightly stiffer than the rears. I may need to get it realigned at some point because it looks like the left side is higher than the right and it's bothering me. It's fine for now though.

Truthfully this car will probably never be perfect but as I've said many times already, converting it to a stick and EFI has made it 200X more fun to drive than when I bought it in 2018. And just because it doesn't make 600 ponies or do high-speed donuts at will does not make it an inferior experience. Taking the back roads home and banging gears through the turns like I'm in a vintage Trans Am road race will never get old.

More to come.
 
Love your story over time with your car. Makes me think about the 26 years owning my fury and going from 383 2bbl to efi, turbocharged, overdrive and all the experiencing life in getting there!
 
Love your story over time with your car. Makes me think about the 26 years owning my fury and going from 383 2bbl to efi, turbocharged, overdrive and all the experiencing life in getting there!
Thank you! Not quite 26 years (!) but I have been through a bunch with this car. Basically the only things I didn't do or touch are the paint, basic short block, rear end, front brakes and some of the interior.
 
You shouldn't have any issue getting the car aligned. I take my car to the local tire shop and the guy dials it in. Alignment specs are fairly generic. They'll just set it up for radial tires and power steering. Shouldn't be a big deal, you'll be in and out of there in 30 or 40 minutes.
Having worked on stuff like this for people who took to the local tire shop. If they have a guy who knows how to align a car the computer machines are far and away the best way to go. Most of the techs are too young to understand the process of how to turn the adjusters and wind up bending the tabs on the body. You need to release some of the weight of the car to turn them. Or jack the car up turn the adjusters let down and then recheck the numbers. And as well most your younger alignment techs simply like to turn the numbers green, but on the older cars you have to set them to pull slightly against the crown of the road. I taught alignments at a Tech College for 26 years.
 
Having worked on stuff like this for people who took to the local tire shop. If they have a guy who knows how to align a car the computer machines are far and away the best way to go. Most of the techs are too young to understand the process of how to turn the adjusters and wind up bending the tabs on the body. You need to release some of the weight of the car to turn them. Or jack the car up turn the adjusters let down and then recheck the numbers. And as well most your younger alignment techs simply like to turn the numbers green, but on the older cars you have to set them to pull slightly against the crown of the road. I taught alignments at a Tech College for 26 years.
That post was from 2 1/2 years ago. Not sure if you read anything afterwards but the car was in fact "computer" aligned in Nov. of 2020 at a local tire shop and has been fine since then. If you go back and read what I wrote in post #21, you'll see that the alignment process itself was a bit of a struggle. I was there for several hours while they tried to get it right. Since then however, there have been no handling, alignment or tire wear issues to speak of - it's all good.

About a year later in Dec. of 2021 I installed QA1 single adjustable shocks all around which really helped to round out the whole package. In fact, as I just mentioned today in post #91, it handles pretty darn good for a big, heavy car.
 
Welp, as of 7.27.23, the car has been sold. Thanks to all who showed interest and/or replied here.

Honestly, I knew it was time. The last few times I drove it I just felt like I was not enjoying it as much. It ran and handled great and looked good doing it but sometimes you just want a fresh start. Happens. I've learned that I need something to tinker with and this car didn't really need much of anything. It almost became just a regular car that you fill up with gas and just go. My original plan with the car was to drive it so mission accomplished. On to the next one!

I'll be honest, I'm not sure if I want another B Body. This was the 3rd one I've had and at some point during my ownership of them I've come to the conclusion they've all been too big. Though I don't know how realistic it will be, I'd like to find an E body for my next car. I know E Bodies are similar in size to B bodies but every E platform car I've been in feels more "right" to me than a B. Maybe it's because the seat seems lower in the chassis, maybe it's the slightly shorter wheel base... I can't put my finger on it exactly but it's noticeable.

Could be another A body in my future as well if I find the right deal. I had my eye on a '71 Demon recently but after seeing it in person it became apparent that the seller was asking way too much for what the car was. I've also always had a thing for '69 Darts too. Not a huge A Body 'Cuda fan. Guess we'll see what's out there.

Getting loaded up and heading out to the new owner.
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Strapped in, ready to go. Tough maneuvering a big rig around my neighborhood, had to go out and stop traffic on a main road so the driver could turn around.
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Goodbye friend!
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- Greg
 
I'm not sure if I want another B Body. This was the 3rd one I've had and at some point during my ownership of them I've come to the conclusion they've all been too big.
That's funny you bring that up.
That's the exact reason why I love B-bodies so much, and the styling of my 70 Roadrunner is so perfect to me.
At 6'3" and 270 pounds, I know an A-body is too small, I test drove a 440 RB powered A-body but that convinced me.
So fit is first, and the combination of the "futuristic" look of the front and back of my 70 Roadrunner but retaining the lines of the 68&69 sheet metal is the ideal look and fit.
Good luck with your search.
 
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