Any feedback on a 518 in a Fusey?
- Thread starter feets
- Start date
The diesel converter is certainly strong enough, there might be an issue with the low RPM rating of a diesel ie 2250 to 2500 RPM. Your 440 can safely turn up to 4500 RPM. so I do not know if the diesel unit would function properly at that RPM range, something you would want to check out. Also, if memory serves me correctly, the diesel units have a different bolt up pattern than the gas units so finding a compatible flex plate might be a problem.
The transmission got a well deserved "bad rap" because they were coming in burned to the ground at under 40k on the early versions. The converters were usually the primary cause, but does that really matter, the transmissions were failing. The solenoids that controlled the converter lock up were also a POS. They had a bad habit of sticking. If they stuck in the closed position, nothing bad happened, the lock up feature just was disabled. If the solenoid stuck in the deployed position, the converter stayed locked all the time and the vehicle was pretty much undriveable. The solenoids also stuck partially deployed which caused an oil flow restriction to the lockup feature which caused the converter to slip and burn out. All in all a piss poor design. To their credit, Chrysler fixed these problems with the transmissions on retro and follow up design changes.
Dave
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clarkie383
New Member
Interesting
OK feets, you have a right to be riled up... but there are a lot of folks interested in what you're doing. I have no good advice for your build, it is not what I would do or recommend someone less equipped to do their own work take on... but I believe you will pull it off OK... and would be interested in your honest evaluation of the results.
BTW, around here, your harshest critics could easily become your best friends once they see you're serious... lots of techs and lots of guys who coulda been... FWIW, your fuel pump statement was already defended by @CBODY67 prior to your reply. None of us have all the answers, but there are a bunch of guys who are hard to find weakness in here (not me).
"Would you be happier if I showed you the mounting brackets and pump block off plate?" YES!... We love pictures, and they help us understand what's going on so much better than words sometimes. I don't mean to be picking at you, just letting you know I'm interested.
I had guessed the work would all be done by you, thanks for clarifying.
"You never get your money back out of an old car like this. Instead, you build it to be what you want it to be. What makes me happy is likely different than what makes you happy." Lots of us will feel the same way... IMO, you didn't start hotrodding a cherry car, I'm all for it...
Please continue, not that you need any of our approval...
The issue of "torque capacity" can be a somewhat vague spec, from what I've seen. Certainly, each trans design has a design-limit, but there have been some trans families originally meant for 4 cyls and V-6s in the GM 1978 intermediate-size re-design that went on to be behind engines with more power, by a good bit. Namely the Turbo 200 family! At one Olds dealership, many grenade as they came off the transport truck. Trans plant "sabotage"? We didn't have quite that situation where I worked, though. The engines usually had more like 120 horsepower, BUT then it showed up behind the Buick GN Turbo motors! A disaster? Not quite.
Why would Buick put that "weaker" trans behind their hot rod factory turbo motor, knowing full well what the cars would be used for? It, like some other components on the car, were used as they took less power to run, meaning more power to the ground. Most of the people who raced the cars weren't completely stupid. They knew the lineage of the trans and that it might fail, so when it started to, many had the gumption to get it "enhanced" before they got embarrassed by it. Sure, the basic design was still what it was, but with upgraded internal frictions and such, better reliability.
Even more amazing than that, one guy put a Chevy small block TBI pickup motor 350 into a Pontiac A6000 fwd car, with the existing T125 transaxle in it. Upped the line pressure, had some stronger axles built, and it apparently lived long enough for the magazine article on it.
In a "Two Guys Garage" segment, they did some upgrades on a Cummins pickup. Upped the turbo output, installed a Jake Brake, and also adjusted the automatic trans line pressure upward a certain amount.
As for the Daks, past the empty weight (quoted) of 4100 lbs, add the rated load weight, driver, gear, and even 4wd items and things can get past another 1000lbs pretty quick, which is "Imperial Territory". And then it's required to run up hills with all of that load and such, reliably. BTAIM
No doubt, as with rear axles, it's not particularly the "smooth application of power" that breaks things, it's the "shock loads" that do it. Sometimes, the metal used in the clutch packs and such that can be upgraded for additional toughness. Other times, it's the quality and endurance of the friction materials that do it, on factory line pressures. End result is that torque capacity is increased over the factory design levels.
The lock-up converter issues on the earlier 518s could have been due to the quality of the friction materials, the cost of such, OR the manner in which the converter was modulated. It's far easier to dismiss that whole assembly as "junk" or "weak" and not further investigate "Why" of the situation for a more specific determination. Obviously, Chrysler addressed it to put an end to their warranty claims on such failures.
As much as owners tend to over-load their Dodge pickup-chassis vehicles, the 618 was an obvious upgrade for those applications. Seeing one pulling a gooseneck trailer with 16 large round bails of hay is not an uncommon sight in many areas of TX many times of the year. Then, too, it was well-known of the weakness of poor trans cooling in their truck vehicles, from the earlier round-Ram models. One trailer magazine did a test and the Dodge was running about 250 degrees trans temp just running down a flat road at highway speed. FAR too high under a moderate load, to me. Obviously, more and better trans cooling was needed, but "not there" for some reason.
In the end, a particular trans family does have it's design power capacity, but that's in the "as produced variation", usually. Doesn't mean that some hard parts or friction upgrades can increase it.
Happy New Year!
CBODY67
Why would Buick put that "weaker" trans behind their hot rod factory turbo motor, knowing full well what the cars would be used for? It, like some other components on the car, were used as they took less power to run, meaning more power to the ground. Most of the people who raced the cars weren't completely stupid. They knew the lineage of the trans and that it might fail, so when it started to, many had the gumption to get it "enhanced" before they got embarrassed by it. Sure, the basic design was still what it was, but with upgraded internal frictions and such, better reliability.
Even more amazing than that, one guy put a Chevy small block TBI pickup motor 350 into a Pontiac A6000 fwd car, with the existing T125 transaxle in it. Upped the line pressure, had some stronger axles built, and it apparently lived long enough for the magazine article on it.
In a "Two Guys Garage" segment, they did some upgrades on a Cummins pickup. Upped the turbo output, installed a Jake Brake, and also adjusted the automatic trans line pressure upward a certain amount.
As for the Daks, past the empty weight (quoted) of 4100 lbs, add the rated load weight, driver, gear, and even 4wd items and things can get past another 1000lbs pretty quick, which is "Imperial Territory". And then it's required to run up hills with all of that load and such, reliably. BTAIM
No doubt, as with rear axles, it's not particularly the "smooth application of power" that breaks things, it's the "shock loads" that do it. Sometimes, the metal used in the clutch packs and such that can be upgraded for additional toughness. Other times, it's the quality and endurance of the friction materials that do it, on factory line pressures. End result is that torque capacity is increased over the factory design levels.
The lock-up converter issues on the earlier 518s could have been due to the quality of the friction materials, the cost of such, OR the manner in which the converter was modulated. It's far easier to dismiss that whole assembly as "junk" or "weak" and not further investigate "Why" of the situation for a more specific determination. Obviously, Chrysler addressed it to put an end to their warranty claims on such failures.
As much as owners tend to over-load their Dodge pickup-chassis vehicles, the 618 was an obvious upgrade for those applications. Seeing one pulling a gooseneck trailer with 16 large round bails of hay is not an uncommon sight in many areas of TX many times of the year. Then, too, it was well-known of the weakness of poor trans cooling in their truck vehicles, from the earlier round-Ram models. One trailer magazine did a test and the Dodge was running about 250 degrees trans temp just running down a flat road at highway speed. FAR too high under a moderate load, to me. Obviously, more and better trans cooling was needed, but "not there" for some reason.
In the end, a particular trans family does have it's design power capacity, but that's in the "as produced variation", usually. Doesn't mean that some hard parts or friction upgrades can increase it.
Happy New Year!
CBODY67
In the later '60s and into the '70s, I spent many hours combined at the local Chrysler dealer. Just seeing what new cars they had or in the service dept as I got our cars worked on. I read most of the car magazines and especially road tests of Chrysler vehicles. I felt I was pretty knowledgeable in those areas of product and such. BUT when I got into the dealership parts business (GM) and started going through the parts books at the Chrysler store on Saturdays, there were many things which existed in there that I'd never heard of. Like part numbers on rear sway bars for '60s police cars, with the note "LAPD" after them, at a time when rear sway bars were only on Chryslers with radial tires on them. OR chasing HD shock absorber number progressions. And discovering that many allegedly unobtanium parts (after the generally-accepted "10 year rule" of availability of mechanical parts had been passed). Got an AM/FM Multiplex set-up for my '70 Monaco that way (in about 1978). Only had to build the harness to the back speakers. So, this Imperial electric fuel pump/AIR pump location situation is one such situation.
One thing I was blessed with was the ready-availability of credible mentors and product information sources for questions I might have on product and such, in my 4 decades in GM parts. Asking those questions and doing my own research answered a LOT of questions and greatly expanded my horizons of product knowledge. Also, in areas of Chrysler and Ford issues, too. Great learning experiences, even in here.
Enjoy!
CBODY67
It was rather difficult to hang a mechanical fuel pump off the engine when the factory used that position as a mount to hold the air pump.
Amazing, but true.
At least we didn't get into the first application of 4 channel electronic anti lock brakes. Luckily, they didn't check that box on the build sheet for my car. I'm not sure how well that system would hold up 46 years later.
Amazing, but true.
At least we didn't get into the first application of 4 channel electronic anti lock brakes. Luckily, they didn't check that box on the build sheet for my car. I'm not sure how well that system would hold up 46 years later.
Carmine
Old Man with a Hat
Hey, thanks for the idea. I hadn't realized you replied last Wednesday and I didn't see it until now. Soon as it warms up to 35 around here, i'll put on some shorts and slide under to have a look at that spring.
69 300 vert
Well-Known Member
78Brougham
"Chump"
Sorry for the misunderstanding... I just never heard of it before, so I never had to look it up. I thought maybe some joker wired one up instead of the mechanical pump. Our cars get butchered pretty bad sometimes. You learn an awful lot on this site. Thanks for posting that info from the FSM very cool!
Good luck with your project. I still wish you'd think about getting her in for that paint job. She'd look awesome!
I love my '73. Second one I've owned.
Good luck with your project. I still wish you'd think about getting her in for that paint job. She'd look awesome!
I love my '73. Second one I've owned.
@Tobias74 has/had? a 73 with that system, I was really looking forward to more information from him regarding it's function... his still works.
Here's another file. Automobile Manufacturers Association specs provided by the manufacturer (Chrysler) for all models produced in a given model year (Imperial for 1972, in this case). LOTS of numbers! Wasn't aware that, according to these, when Chrysler stopped using the 2.94 rear axle ratio on Imperials, they went to a 3.23 gear (like '71-'73?)
In any case look at the "Fuel System" area.
CBODY67
In any case look at the "Fuel System" area.
CBODY67
69 300 vert
Well-Known Member
Very interesting. California Imperials only rated 216 hp (+-5hp) and 340 torque. The double wall exhaust pipe is also interesting, thought that to be a GM only thing.
Robert
Robert
The gear change to 3.23 happened in 1972 to help bolster performance with the lower compression motors.
Keep in mind that it really wasn't a 130 hp drop that year. Going from net to gross ratings accounted for most of that change.
bajajoaquin
Senior Member
Any update here?
I’m planning to have an A518 behind the 440 as well in my 73 imperial as well. As far as I concern JVX has everything to couple the engine and transmission. The crossmember must be modified or custom fabricated and the tunnel might have some “hammer adjustments”. It’s a lot of work. I have to go this way because I have a 3.73 rear end and definitely highway has been compromised. In your case I’d change the rear end ratio in favor to a 2.94 or even taller, but I wouldn't go any further than 2.60. The car will be felt sluggish. A black Imperial is beautiful and unique.
70bigblockdodge
Old Man with a Hat
Wow dug up a 3 year old thread.
Trans is still a POS.
Trans is still a POS.
It's amazing. My transmission has over 300,000 miles on it and still pulled 14,000 lbs through the Texas hill country without missing a beat. 
As for the Imperial, life got in the way.
However, I'm making progress.
The Edelbrock heads have been ported and the valve work is underway. This weekend I'll be clearancing the block for the new 4.5" crank that is part of my 541" stroker kit.
The 518 is still destined to go under the car. It will easily take the torque after I go through it like I would any 727 transmission being used in the same capacity.
As for the Imperial, life got in the way.
However, I'm making progress.
The Edelbrock heads have been ported and the valve work is underway. This weekend I'll be clearancing the block for the new 4.5" crank that is part of my 541" stroker kit.
The 518 is still destined to go under the car. It will easily take the torque after I go through it like I would any 727 transmission being used in the same capacity.
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