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Transverse & longitudinal 4100s in 84/85 Eldos?

Started by 13912, February 03, 2015, 08:41:22 PM

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13912

In reading the many posts on 4100 issues, a number appear to me to say there were both transverse & longitudinal engines. Is that true & why offer both ? Did I misinterpret the posts?
Thanks
Bob

bcroe

Quote from: 13912In reading the many posts on 4100 issues, a number appear to me to say there were both transverse & longitudinal engines. Is that true & why offer both ? Did I misinterpret the posts? Thanks  Bob   

The original FWD 66 Toronado was based on a somewhat conventional longitudinal engine
and TH400 trans folded back under the engine.  Same for the 67 Eldo.  This basic design,
downsized for Gen III E cars in 79, was carried through to 1985.  Since the Cad 4100 had
to mount to the same layout as Toro and Riv, it needed longitudinal mounting. 
Bruce Roe  CLC  # 14630

TJ Hopland

Yep the 82-85 4100 that went into the Eldo's and Sevilles' was basically the same one that went into the RWD cars.   Just like earlier models and other makes they were the same engines just had some different accessories to accommodate the FWD like a funky oil pan and exhaust manifolds.  The reason you hear people talk about that for 85 was that was the year there were both transverse FWD cars, RWD cars, and the longitudinal FWD cars.   86 they all went to transverse except the Brougham which got the Olds.

The Eldorado was one reason the intake on the 472/500 was basically inside out.  Normally the runners would have curved up from the heads and put the carb a few inches higher on the intake.   Because of having to get a drive shaft under the oil pan the engine sat higher than it normally would so they had to keep the carb low to clear the hood.   That's why the engine / air cleaner kinda looks really low in the C cars.

I don't seem to have a good picture, here is kinda a engine shot of my 81 Riv with my assistant helping me replace glow plugs.

     
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Roger Zimmermann

1956 Sedan de Ville (sold)
1956 Eldorado Biarritz
1957 Eldorado Brougham (sold)
1972 Coupe de Ville
2011 DTS
CLCMRC benefactor #101

TJ Hopland

Seems like I read that the 4100 was originally going to only be transverse and they planned on introducing it in 84.  The only reason there was a longitudinal version is that was what they came up with for testing since there was not yet a medium duty transverse transmission or car body it would fit in.  They figured the longitudinal FWD and RWD cars would stay with the 8-6-4 and the transverse would get the 4100's.  What a nice plan...   Too bad the testing / testers ended up being pretty much everyone who bought a 82-83 Cadillac.   
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

James Landi

Was a sad time for Cadillac-- they turned out beautifully proportioned cars, and the significant downsize and weight reduction included independent four wheel suspension and a bunch of terrific improvements.  The digital technology following the failed 4-6-8 was rugged and lasting... but the 4100 was, well ....I've owned 4, still own one, but, my 85 Biarritz has a late 70's Olds 265 cid hauling it around.

76eldo

The aluminum block and bad thread fiasco was repeated in the Northstar as well.

Huge disappointment to me with the 99 Eldo I had for a while.

I have owned at least 8 HT4100 cars with two engine failures.  A trained Northstar tech tells me EVERY one will have failures in the thread and headgasket area from the 90's through about 2004.

Brian
Brian Rachlin
Huntingdon Valley, Pa
I prefer email's not PM's rachlin@comcast.net

1960 62 Series Conv with Factory Tri Power
1970 DeVille Conv
1970 Eldo
1970 Caribu (?) "The Cadmino"
1973 Eldorado Conv Pace Car
1976 Eldorado Conv
1980 Eldorado H & E Conv
1993 Allante with Hardtop (X2)
2008 DTS
2012 CTS Coupe
2017 XT
1956 Thunderbird
1966 Olds Toronado

936CD69

TJ is correct. The FWD "C" deVille Fleetwood was originally supposed to be introduced as a late 83/early 84 model. Reliability problems with the transverse 440T-4 transaxle delayed introduction until April of 84 as 85 models. The 4100 was never originally to have been installed in a longitudinal car. CAFE average requirements and issues with the analog 8-6-4 computing power forced Cadillac to come up with an alternative longitudinal engine ASAP. The only thing in the pipeline was the HT4100. so it was "forced" into production a year earlier than planned in a different configuration than it was designed for. It was designed to move a 3500# FWD car and ended up in 4000# + cars. I have owned 2 early 4100s and swear no matter how pretty that 82-85 Deville Fleetwood Brougham, Eldo or Seville is, I will not own another )might make an exception if a Jasper rebuilt engine is included with the sale  :))
Craig Brillhart CLC# 26217
1993 Sedan deVille Spring Edition Carmine Red White Top-SOLD!
1993 Sedan deVille Spring Edition Triple Black
CLCMRC Benefactor #302

Jeff Rosansky CLC #28373

I bet your "assistant" loves the glow plugs!
Jeff
Jeff Rosansky
CLC #28373
1970 Coupe DeVille (Big Red)
1955 Series 62 (Baby Blue)
Dad's new 1979 Coupe DeVille

76eldo

Craig,

From what I recall from the early 80's the High Technology was advertised heavily and rolled out with a lot of fanfare.  I don't think it was forced, I think it was planned as the new power platform.  Certainly is wasn't tested enough and became a real headache for Cadillac.

If anything, the V-8-6-4 in 1981 was a stopgap measure to try to meet the CAFE standards somehow.

Brian
Brian Rachlin
Huntingdon Valley, Pa
I prefer email's not PM's rachlin@comcast.net

1960 62 Series Conv with Factory Tri Power
1970 DeVille Conv
1970 Eldo
1970 Caribu (?) "The Cadmino"
1973 Eldorado Conv Pace Car
1976 Eldorado Conv
1980 Eldorado H & E Conv
1993 Allante with Hardtop (X2)
2008 DTS
2012 CTS Coupe
2017 XT
1956 Thunderbird
1966 Olds Toronado

TJ Hopland

Quote from: 76eldo on February 04, 2015, 10:33:04 PM
From what I recall from the early 80's the High Technology was advertised heavily and rolled out with a lot of fanfare.  I don't think it was forced, I think it was planned as the new power platform.  Certainly is wasn't tested enough and became a real headache for Cadillac.  If anything, the V-8-6-4 in 1981 was a stopgap measure to try to meet the CAFE standards somehow.

The 4100 was supposed to be a big deal but the problem was it was supposed to come out for the 84 model year in even further downsized cars.  The 8-6-4 was supposed to be the stop gap to to allow them to meet the CAFE (Corporate Average Fuel Economy) standards until the downsized 84's with the 4100's came out.  The 'failure' of the 8-6-4 is what rushed the 4100 into production 2 years early and put it in bigger cars than it was intended for.  If they had got 2 more years of testing and development and the cars they designed it for things may have been a lot different.   The CAFE standard was per make, not GM overall.  That is why makes like Cadillac had huge problems,  all huge cars.  At least a line like Chev had some small fuel efficient cars to offset the land yachts.

The 8-6-4 was a DEFI  (Digital Electronic Fuel Injection) system.  They actually had a microprocessor and memory in em.  The DEFI system debuted as the standard engine for 80 Eldo and I think an option on the Seville.   It was basically a similar system as what went on several GM's for 81 but only the Cadillac has the built in diagnostic stuff.  The others needed a scan tool or at least a paperclip.  The Corvette's had the 'crossfire' injection system that was 2 1 bbl throttle bodies on opposite corners of the intake.   

It was the 75-80 EFI system that was analog.  That system was standard on the Seville and an option on most of the other cars most of those years.     These didn't have a micro processor or memory.  The 'tune' was done with resistor packs so it was better than the mechanical FI systems but not as dynamic as the digital stuff. 

I think the 8-6-4 would have worked a lot better if they had been able to do it with a sequential multi port injection but I think that was 5-10 years out at that point.  It was very early in digital EFI technology and it used a 2bbl throttle body injection system, basically what was on the 87-95 trucks.   If you think about all the changes to the flow and turbulence to the air that already had the fuel in it in the intake manifold as the cylinders came and went you can easily imagine why the transitions were not the smoothest.  You had air that was already mixed with fuel headed down the intake for a cylinder then suddenly the flow is shut down.   I bet the fuel tended to come out of suspension and puddle which had to make it very difficult to keep ideal mixtures.   With the modern deactivation systems there are individual injectors for each cylinder which they also deactivate so they don't have as much trouble controlling the fuel.   It also had to be tricky to get the range in the 2 injectors.  Full throttle those had to be able to dump a lot of fuel but they also had to be able to shoot a tiny amount when cruising on 4 cylinders.   They would have had to be a little on the sloppy and inaccurate side at one of those extremes.     
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

mgbeda

The biggest problem with the 8-6-4 was that it was rumored (I'm not sure if it happened, or if it happened more than once) that the solenoids that deactivated the valve train in the turned-off cylinders could make a spark causing an engine fire.  This freaked people out.  People might complain about the deactivation being a little rough, but that's a point against buying a Caddy, not "Game Over, I'm getting a (L-word)".  That's why the 8-6-4 was one year only.

I haven't heard about this "problem" once from a CLC member so I suspect it was overstated, if not a false rumor.  But that can be enough.  Look at all the people that stopped buying Audi's because they "spontaneously accelerated", even though Audi proved in court that it was physically impossible, at least back in those days before drive-by-wire cam along.

-mB
-Mike Beda
CLC #24610
1976 Sedan DeVille (Bessie)

TJ Hopland

Since we got the original question answered I guess we can continue off on this tangent.......

Quote from: mgbeda on February 05, 2015, 02:38:03 PM
The biggest problem with the 8-6-4 was that it was rumored (I'm not sure if it happened, or if it happened more than once) that the solenoids that deactivated the valve train in the turned-off cylinders could make a spark causing an engine fire.

I never heard that before either.  I'm not even sure where that would come from.  I don't think they were very high current so they should not have run warm or created much of a spark if there was a connection issue.  The connection was outside the valve cover but even if it was inside the valve cover I kinda wonder how flammable what is floating around the valve covers are.   

Anyone got a theory?   I'm just thinking if you can put a electric motor inside the gas tank you should be able to put a couple coils 'in the crankcase'.    Valves were closed when the cylinder was deactivated so there should have not been extra fuel running into the crank case or anything like that.   Valve covers were plastic and known to crack and leak but leaking valve covers were not exactly rare and the leaks would be at the bottom not up where the solenoids were so that does not seem like part of the 'problem'. 





If you can't figure out how they worked from those photos basically imagine 2 crowns stacked pointy part to pointy part except the points are actually flat and a spring between them.   Normally the 'points' are aligned which means when the push rod pushes those act as the pivot point and force the valve to open.  When the solenoid activates it rotates the top 'crown' so the the 'points' don't align.  This means the next time the pushrod pushes the crowns interlock so the rocker just lifts up instead of pushing the valve open.  The cool part about this was it didn't matter when the solenoid activated or deactivated.  If the valve was open at the time it continues to open for that cycle but as soon as the pressure is off the crown moves.  Same thing if it was off during that cycle, it aligns for the next one.    These crowns are what they call window, blocking plate, and  body projection on the above diagram.    That part of the system apparently worked fairly well. 

I have worked on and driven a few but never actually owned one.   Came close to buying one a couple years ago but the car had too many other issues and the guy wanted too much.  Ended up finding the Riviera with the diesel instead so I figured that counted as weird enough.   

StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Eric DeVirgilis CLC# 8621

#13
More than anything else, the V-8-6-4 had been introduced primarily to help Cadillac lessen its image as a "gas guzzler", despite real world fuel mileage improvements were practically nil compared with that of the 1980 models.

With gasoline expected to reach $2.00 at the time, fuel economy had become a more of a factor as never before - even among new Cadillac buyers.

In retrospect, Cadillac did far more damage to itself by overreacting to fuel price fluctuations without the engineering advancement needed for fuel economy without sacrificing product quality: Cadillac clientele could accept a relatively small penalty at the pump as part of the cost of luxury car ownership whereas sacrifice to reliability would never be acceptable.

Personally, I am unaware of any mechanical problems with the V-8-6-4 engine. The only problems with the plant were electronic in nature - practically all of which were eliminated during the warranty period which had been extended to 5 years/ 50,000 miles for 1981 models equipped with the V-8-6-4.   
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

James Landi

In response to Eric's post:  I have often wondered about how the 8-6-4 lasted over time. It's been 35 years, and I sometimes see these cars for sale.  When the initial issues occurred, and then there was the tragic death that occurred, attributed to engine failure on Long Island, New York, that was the end of that engine design... but what about the engines that are still operating today?  Are there still drivability issues? Are they reliable?

Eric DeVirgilis CLC# 8621

#15
Quote from: James Landi on February 06, 2015, 10:49:56 AM
In response to Eric's post:  I have often wondered about how the 8-6-4 lasted over time. It's been 35 years, and I sometimes see these cars for sale.  When the initial issues occurred, and then there was the tragic death that occurred, attributed to engine failure on Long Island, New York, that was the end of that engine design... but what about the engines that are still operating today?  Are there still drivability issues? Are they reliable?

Mechanically, the V-8-6-4 is as robust a Cadillac engine as any. It is essentially the same engine block that dates back to the 472 of 1968.

Its main issues were electronic - primarily poor electrical harnesses, connectors and such. As stated, these issues have been addressed long ago and the V-8-6-4 marks the very last in the line of Cadillac's venerable cast iron V-8. 

V-8-6-4 cars mark another "last": The final year of 3 speed THM 400 transmission (in standard models). This transmission was also an ultra durable unit that had been around for a good many years - far better than the crummy "Metric 200" transmission that followed in 1982.

I would take a V-8-6-4 Cadillac any day.
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

g27g28

Much of the reason for the 8 6 4 was CAFE standards.  How quickly we all forget the real shame Cadillac introduced in 1981, the Cimarron, which was also for CAFE.  I purchased a used 81 Sedan DeVille in 1991 to drive back and forth to college, 50 miles round trip.  It was "active" all the time I had it.  When it was in 6 there was a slight vibration feeling and some slight surge feelings as it switched back and forth, most people would never know any difference.  I replaced one fuel pump and replaced the ECM once while I had it.  I remeber having to work on the alternator quite a few times.  Other than other normal wear items those were all the problems I had with it.   I put well over 100 k miles on it and it was a very dependable car.  Many of those miles were on dirt roads, so much so that I had to replace the fuel filter canister once as so many rocks had hit and dented it that it started to leak.  It was on the drivers side mounted in front of the rear tire.  The car had well over 250k when the transmission went out and it was retired.  If I had the chance to buy one now I would not shy away in the least. 
1941 Series 62
1954 Coupe DeVille
1978 Phaeton
1980 Fleetwood

Eric DeVirgilis CLC# 8621

The transitions from 4 to 6 to 8 are far more subtle than the transmission changing gears. The transitions are only perceptible when cylinders are activated, never when deactivated.

My main complaints are:

The brief pause when you go to accelerate in the 4 cylinder mode - while the system transitions back to 8.

Vibration in 6 cylinder mode which is very noticeable. Fortunately the system is either in 8 or 4 cylinder operation 95% the time. 
A Cadillac Motorcar is a Possession for which there is no Acceptable Substitute

TJ Hopland

Ya disconnecting the 3rd gear wire from the trans was the way to do it.  Over the years people tired many other methods.  The worst was unplugging the solenoids on the rocker arms.   Problem here was that when the computer thought it was shutting down cylinders it put in less fuel which was a problem if the cylinders were still all operating.

I don't think they ever came up with any sort of fix for these cars either software or hardware over how they were when they left the factory.  I believe for the 82 model year (when many more GM's got EFI) they went to a completely different style of electrical connectors for all the engine management stuff that were much more reliable than what they had used on the 80 and 81's.  I think they also redesigned several of the sensors to improve operation and reliability.  I lot of the 82 and up sensors lasted till 95, many of the 80 and 81 were their own thing and apparently can be hard to come by these days. 

The 200 'metric' transmission I think came out around 1975.   I think it was the low cost replacement for the powerglide and went into cars like the Monza.  The first Cadillac to get it was the 78 Seville with the diesel option.  The 78 shop manual I think called it the diesel transmission.  The 325 trans for the 79-81 E body was based on the 200 but with some improvements that apparently went into the 200C.  I don't think the 200c was very popular in the 80's because the 200 4r overdrive came out in 81 on the V6's and 82 for everything else.  82 was also the year the 700r4 came out for the Chev's which was more along the lines of the 350.   The 82-85 E bodies got the 325 4L which had overdrive.

There is no reason the mechanical part of the deactivation could not be almost instant.  I think the delay and roughness was what I was talking about earlier where the flow in the intake was so disrupted as the cylinders came and went that it took a few seconds for things to clear out and get back on track so to speak.   The modern deactivation systems have a separate oil line to special lifters for the deactivating cylinders.  There is a solenoid that controls the oil to this passage.  In one mode it lets the lifter collapse so the valve does not open, in the other mode it operates normally so not really any different than the Cadillac system, it can change within one cycle.  The difference in the modern stuff is the sequential port injection, they can also shut off the fuel on an individual basis.  The Cadillac system was not much better than a Carb, basically the whole intake was fed from a single point so I think the fuel would get 'lost' in the intake.     

 
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

Whit Otis, 1188

James,  In response to your question on the 8 6 4 as to whether many are around and are they reliable, I have a friend who has an 81 Eldorado with a fully functioning 8 6 4.  The first time I drove it, I asked if he had modified it to run on only 8 cylinders.  The answer was an emphatic "NO."  For the life of me, I have yet to figure out what all the complaints were about..... yes a slight "feel" at the transition point, but the car is smooth, powerful and reliable.  Frankly, I think the press and a lot of subsequent over reaction is what killed a design that to my way of thinking was genius at the time.  Today, it's no big deal with all the computerization.  Back then, this was a real accomplishment that worked, best I can tell.

Whit Otis
Whit Otis -
1941 6219D Custom
1941 6219D
1940 7533F
1986 Mercedes Benz 560 SEL
1999 Bentley Arnage
2019 XT5
Drawing of AP Sloan Custom by Terry Wenger