whats shared between A-body/W-body/U-body?

[TheGreatPotato]

I was wondering if anyone could give me some general rules of thumb about this topic...

My understanding is that the U-body minivan is primarily based off "lightly modified A-body running gear", although the specifically named lumina is a W-body, so before I get too ahead of myself with asking about swapping one thing into another, in general what kind of stuff is a bolt in replacement even if it's slightly different (the differences may be desirable) and what kind of things are in the custom fab territory to make work? (i'm alot more comfortable turning wrenches than changing anything especially if I screw up and can't change it back, also not looking to spend hundreds on machine work but mostly pull and replace)


My biggest exploration at the moment is things like motor mounts and such, like i'm wondering if since the 2.5L Iron Dukes and GM 122 2.2L 4cyls came in the cars, could I swap one into the minivan as a bolt up with all factory parts/mounts/etc and could I use a 5 speed manual out of a US lumina or celebrity as well... even considering 4.3 V6 olds diesel, and the european 1.9 Citroen diesel (if it would bolt to a US manual transmission/trying to find what stick was used there and if it was a special block, or special transmission to make it work), as well as eventual future performance options which i'll save for a separate thread because I need the eco vehicle before the fun vehicle.

[Duke George V]

To my knowledge, nothing is shared with the W platform. The Lumina name is something of a coincidence. I think GM wanted to make Lumina kind of a sub-brand within Chevy.

As for economy, the best fuel economy also comes from the most powerful van: the 3800-powered vans get much better fuel economy than the 3.1 versions. I regularly saw 18-19 mpg in the city out of my Trans Sport, with as high as 27 on the highway. My old Silhouette, on the other hand, with its 3.1 and three speed, was basically 18 mpg all the time. Similarly, a 6000 I had with an Iron Duke couldn't crack 23 mpg highway, while a 2.8 V6 Celebrity got me high 20s, and even over 30 once or twice.

Having said that, a rule of thumb about any engine swap: with enough time and money, one can swap any engine into any car. You will spend a lot of time adapting a four cylinder into a van, since it never came with one in the US. Just the wiring alone will make you want to kill yourself. The Brazilian market Lumina had an Opel 1.8 OHC, while the Euro Silhouette used a single cam Quad4, both of which came with a manual transmission. They are both seriously underpowered though, which is a problem shared with the 3.1, so you'll have to flog them mercilessly to get anywhere, killing any possible sort of fuel savings.

I guess the answer to your question is: yes, you CAN swap a four cylinder, but why bother? Less cylinders and displacement do not necessarily mean less fuel used; conversely, more cylinders and displacement do not necessarily mean more fuel used. Why do you think the Corvette is able to get such great highway economy? 'Torque' and 'gearing' are what get you good fuel economy, both of which the Buick V6 version has in abundance.

[86euro]

Do you know the MPG of the '96 model with the 3400? I agree, putting a low output 4 cylinder in a U-van won't have any benefits other than your buddies looking under the hood and saying "huh, that's different".

[Duke George V]

Do you know the MPG of the '96 model with the 3400?

fueleconomy.gov says it is supposed to get 2 mpg better in the city than a 3800, which is possible, since the 3400 vans got a 3.29 final drive (3800s got 3.05). Highway economy is supposedly the same.

http://www.fueleconomy.gov/feg/Find....12434&id=13175

[Jr's3800]

The EPA ratings confuse me... I did 28 Mpg in my van with the L27, with a ported lower intake, head ports were matched to the intake and I added 1.8 roller rockers that made the total valve lift roughly .470-.480 ... with this I did 28 MPG with the AC blowing cold cruise was set at 80 Mph.. If I would have been at 70 I bet I could have done 30 Mpg..

The current set up with the 06 3800, has that bumpy cam( .517 intake and .498 exhaust )... At one point I had 3.33 gears and a fuel rich tune and wost I did was 16 Mpg... I was flooring it a lot... I did 23 Mpg at 80 mph.... did a good bit of uphill passing too lol.... when I slower to 70-73 it was 25 Mpg..


I agree that a 4 Cyl would have the " Wow you don't see that everyday factor " but it would be dangerously slow and would have to run and struggle to get that van moving..

I'd say if you are looking for better economy and it has a 3800, you might consider a 2.84 ratio keeping the stock 1900 stall converter... But even that 2.84 will make it a bit of a struggle for a 3800... It won't be bad, but far from a 3.06..


As for what parts are used... The chassis is derived from the A body wagon iirc... The mounts and the like are A body parts... Some of the other stuff like the cluster and switches are W related... It really seems that GM wanted to get into the van game and used a lots of parts that were already in the parts bin..

Soon I will take my Van on a road trip.. I am curious as to what kind of mileage I can get out of it with the 3.06 ratio and a closer to stock tune..

[lurker]

had my '93 apv 3.1 out on the highway last weekend, 24.5 mpg. missing front hubcaps, ac not working so windows open. was hoping for better.

[turbokinetic]

.....I agree that a 4 Cyl would have the " Wow you don't see that everyday factor " but it would be dangerously slow .....

Reminds me of Driver's Education class at highschool. The school had a Buick Century with V6; and a Ford Escort with.... nothing. I had been lucky and had only driven the Century for the first 3/4 of the school year. Other than that car, I had driven my mom's Nova (a V8 car) any my dad's LeSabre (LG3 3.8SFI). I did not know there was a car as slow as that Escort.

First time I drove it, I pulled out and it was like "nothing's there" at the gas pedal. Mind you we had 4 people in the car so it was overloaded to begin with. I was hoping the loaded dumptruck barreling down the highway coming from behind saw the car and didn't give us an unwanted "boost" from behind.

Years later I was driving a customer's car (some asian thing) and it was SO SLOW that I could only make 45 or 50 by the top of the Interstate ramp and the traffic was running 70 to 80. Had to run the shoulder to build up speed and finally someone let me merge. Was glad when they picked that POS up. Their complaint? The brakes were ineffective. My reply - Yes, the brakes don't seem to work because you have to actualy be moving to feel the brakes work!

After those escapades I have never wanted to have an anemic underpowered car.

David

[babyivan]

Reminds me of Driver's Education class at highschool. The school had a Buick Century with V6; and a Ford Escort with.... nothing. I had been lucky and had only driven the Century for the first 3/4 of the school year. Other than that car, I had driven my mom's Nova (a V8 car) any my dad's LeSabre (LG3 3.8SFI). I did not know there was a car as slow as that Escort.

First time I drove it, I pulled out and it was like "nothing's there" at the gas pedal. Mind you we had 4 people in the car so it was overloaded to begin with. I was hoping the loaded dumptruck barreling down the highway coming from behind saw the car and didn't give us an unwanted "boost" from behind.

Years later I was driving a customer's car (some asian thing) and it was SO SLOW that I could only make 45 or 50 by the top of the Interstate ramp and the traffic was running 70 to 80. Had to run the shoulder to build up speed and finally someone let me merge. Was glad when they picked that POS up. Their complaint? The brakes were ineffective. My reply - Yes, the brakes don't seem to work because you have to actualy be moving to feel the brakes work!

After those escapades I have never wanted to have an anemic underpowered car.

David

Haha, great story.

The only time I would ever own a 4 cyl. is with a manual gearbox, it makes all the difference in the world!

I owned a 00 ford focus ztec 5speed
88 and 91 camry, both 5 speed
96 civic ex vtec 5 speed
94 saturn SL2 1.9 twin cam 4 cyl with 5 speed

The Honda was a slug for sure, I hated it and quickly sold it for a Grand Marquis, haha!
The Camrys were great, not fast, but with a 5 speed not that bad and was SO easy to work on and handled better than most new cars... I miss the 88, was rusting away, but had the original R12 and factory sunroof!
The Focus was good after I installed quick struts and shocks myself thanx to a Halloween super rebate from Monroe!
The Saturn was peppy but horrible on gas and had a terribly noisy timing chain and worst of all, the car was plastic

I miss driving a stick, too bad the gf doesn't drive them... even after repeated attempts to teach her!
My next 5 speed will probably be a Fox body when I can afford to have a 2nd car.

I had 2 U body vans, one a 96 APV with 3.4 (hated the engine, was always paranoid of the LIM and/ HG).
The other one was a 91 silhouette with 3.1 TBI, I friggin loved that thing. I got it for free as a trade-in from one of my dad's customers.
It had leather and sweet Olds alloys. It was white with black stripes, looked like the space shuttle. Ran great, never needed a thing!

They are ugly as sin but really practical. My ultimate one would be with a 3800, I love that engine! They haul ass with it, I think the gearing is shorter.

[Duke George V]

My ultimate one would be with a 3800, I love that engine! They haul ass with it, I think the gearing is shorter.

Both the 3.1 and the 3.8 had the same final drive: 3.05. The difference there is 50 ft-lbs making up for the relatively tall gearing.

[babyivan]

Both the 3.1 and the 3.8 had the same final drive: 3.05. The difference there is 50 ft-lbs making up for the relatively tall gearing.

I was thinking in comparison to a car with a 3800.
My regal with the 3800 didn't feel as peppy as a U body van with one.

[Duke George V]

I was thinking in comparison to a car with a 3800.
My regal with the 3800 didn't feel as peppy as a U body van with one.

I think the Regal, if it was not a GS, might have had a 2.84 or 2.73 final drive. I'm not all that familiar with Regals of that era though. I know this Bonneville I'm driving has the same drivetrain as the van, down to the 3.05 final, and it feels a lot quicker than the van. Probably helps that it weighs a few hundred pounds less.

[Jr's3800]

Reminds me of Driver's Education class at highschool. The school had a Buick Century with V6; and a Ford Escort with.... nothing. I had been lucky and had only driven the Century for the first 3/4 of the school year. Other than that car, I had driven my mom's Nova (a V8 car) any my dad's LeSabre (LG3 3.8SFI). I did not know there was a car as slow as that Escort.

First time I drove it, I pulled out and it was like "nothing's there" at the gas pedal. Mind you we had 4 people in the car so it was overloaded to begin with. I was hoping the loaded dumptruck barreling down the highway coming from behind saw the car and didn't give us an unwanted "boost" from behind.

Years later I was driving a customer's car (some asian thing) and it was SO SLOW that I could only make 45 or 50 by the top of the Interstate ramp and the traffic was running 70 to 80. Had to run the shoulder to build up speed and finally someone let me merge. Was glad when they picked that POS up. Their complaint? The brakes were ineffective. My reply - Yes, the brakes don't seem to work because you have to actualy be moving to feel the brakes work!

After those escapades I have never wanted to have an anemic underpowered car.

David

I have driven a handful of various cars over the years... some 4 Cylinder cars.. Some were peppy and others were outright dogs that I would be afraid of, just could not imagine getting into a situation and not being able to toss my right foot to the floor to get out of it...lol

So to this day I have a bunch of V6's, 3800's at that and they all more than serve the purpose.. I also like knowing it can easily turn 1150 Rpms with no muss or fuss and pick up speed and go...lol

But, the nutty go fast side of me says " I want a David Powered Turbo Charged 3800 ".... But I don't think I ever could as I would get too carried away with 400 HP...lol

[Jr's3800]

I think the Regal, if it was not a GS, might have had a 2.84 or 2.73 final drive. I'm not all that familiar with Regals of that era though. I know this Bonneville I'm driving has the same drivetrain as the van, down to the 3.05 final, and it feels a lot quicker than the van. Probably helps that it weighs a few hundred pounds less.

Yes the older GS's had a 3.06 ratio, the base 3800 Regal was more than most likely a 2.84 ratio.. All 3800 powered vans had the 3.06..

You are driving a Bonneville Eh? 92-99 Bonneville were generally 3500-3600 Lbs, the vans were 3600-3800 Lbs... Having a few hundred Lbs less does make a difference.. I have often said I wished that they had built the van on the H platform, would have been one heck of a daily driver...

[babyivan]

Yes the older GS's had a 3.06 ratio, the base 3800 Regal was more than most likely a 2.84 ratio.. All 3800 powered vans had the 3.06..

Ahhh.... yep, that would do it. My Regal was a Custom, not a GS, so it would've had the taller gears.

[Century7667]

Reminds me of Driver's Education class at highschool. The school had a Buick Century with V6; and a Ford Escort with.... nothing. I had been lucky and had only driven the Century for the first 3/4 of the school year. Other than that car, I had driven my mom's Nova (a V8 car) any my dad's LeSabre (LG3 3.8SFI). I did not know there was a car as slow as that Escort.

First time I drove it, I pulled out and it was like "nothing's there" at the gas pedal. Mind you we had 4 people in the car so it was overloaded to begin with. I was hoping the loaded dumptruck barreling down the highway coming from behind saw the car and didn't give us an unwanted "boost" from behind.

Years later I was driving a customer's car (some asian thing) and it was SO SLOW that I could only make 45 or 50 by the top of the Interstate ramp and the traffic was running 70 to 80. Had to run the shoulder to build up speed and finally someone let me merge. Was glad when they picked that POS up. Their complaint? The brakes were ineffective. My reply - Yes, the brakes don't seem to work because you have to actualy be moving to feel the brakes work!

After those escapades I have never wanted to have an anemic underpowered car.

David

My drivers ed. car was a 1982 Celebrity w/ an Iron Duke. We didn't know better, it was just a car. Enough power for driver's ed. The Celeb went info maintenance one day, and we go a Monte Carlo with the 3.8 (231 back in those days). We were.....easily impressed. No comparison in power.

I knew that the car I drove at the beginning of it's production run would be the first new car I would by at the end of the production run ( a 1996 Buick Century...essentially the same car).

Ken T.