UPDATE: 3800 sunfire swap
 

I just got back from Minnesota with my new engine hoist. Mileage was not good as it was blowing snow hard enough to make road signs shake like they were going to break off.:eek:

The hoist works great. I would be pulling the motor as we speak, but I am tired from the drive and my wife is making lunch, so I will get to it after a nice nap.

more to come....

Interesting...

From your garage:

I'm curious how you figure the 3.8 v6 will get better mileage than a 2.2 four cylinder.

Going to gear it down to near idle in top gear at highway speeds and take advantage of the additional torque and low RPM?

EDIT: or are you talking "relative" mileage improvement (ie. going from a problematic 4-cyl to a v6 that is running well)?

I was able to touch 42 mpg with the 3800 in the olds, and the sunfire will be a good 800 lbs lighter. The gearing is almost identical. The sunfire would always downshift on hills and the 3800 hardly ever downshifted.

Sounds like you can stay in top gear all the time while at speed even if that speed is 85mph.
I bet it will be fairly quick and get very good milage.

Well, it'll be interesting to see the MPG results, that's for sure.

The olds is going in the shed today. I am planning on pulling the 2.2 today and getting the 3800 prepped for removal. There are a lot of wires on these things and it takes time to label everything and make sure it either stays or goes.

The motor is out! :D

There was only 1/8" of clearance to get it out too.:eek: The hoist works perfectly. The guy I got it from had the legs on the wrong sides so it wouldn't roll. I think that is why he sold it. I swapped the lags and it rolled just fine. I am going to try to get the 3800 out tomorrow and then I can get to work putting new gaskets in it and checking it over. I will check the compression and adjust the valves. I will lap the valves if they need it, but the motor is very strong so I will check the compression and go from there.

I am excited to be this far already. My brother came over to help me make some more room around the car so I can set thew two engines next to each other. I still need to pull the dash out of both cars and scavenge the necessary wires. The control arms need new bushings and the ball joints need to be replaced.

The 3800 should be easy to pull since it is more self contained and there is more room around it. I should be able to separate it from the transmission before pulling it and save some work. Here are some pics.

OH...both exhaust systems will get pulled too. The olds system will be reworked to fit under the sunfire.:thumbup:

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Good deal.. Im a fan of chevrolet and the 3800 V6 has more than proved itself over the years...

I dig what you are doing. Kinda reminds me of guys in corvettes getting awesome MPG because of the T56 6speed..

Definately want more pics.

I would recommend using an F40 6sp with the final drive geared up a bit with a 3800, get the holden ECU for lean burn and Voila!

I didn't get to work on the cars today. The weather was getting bad so I brought a truck load of wood in the house. My brothers came over and I found out one of them no longer has a job.:(

The 4T40 already has a higher final drive than the f40 and I don't have the funds to rework everything. I am happy with a good auto and my wife does not like to drive a manual. I just need a car to get me to work and for my wife to get places.

Can you tell me more about this holden ecu?

3800 sunfire swap UPDATE
 

I managed to get the 3800 out of the Oldsmobile today. That baby is heavy! I bet it weighs almost as much as the 2.2 AND tranny put together.:eek: I will be putting new gaskets in it and fixing anything that needs to be fixed and then bolting it to the 4t40. The 4t40 is a lot smaller than the 4t60, but is supposed to be pretty tough. I have seen really tuned up motors bolted to the 4t40, so it should be good to go.

I am pretty sure both cars used the same converter.

I also removed the exhaust from the olds. It was fairly easy and I am glad it is done. It will get cut and welded to fit the sunfire, and the sunfire exhaust will come out with a sawzall.:thumbup:

I have been messing with the idea of putting the 2.2 in my john deere M since it only has 20 HP and could use some GIDDY-UP!!!:eek: Bolting on another 100 horses should be fun right?:rolleyes:

Pics will be up tomorrow, I'm tired.

Isaac: I combined your update into this existing thread about your project.

(No need to start a new thread when you update, or the project progress will be scattered throughout the forum.)

Best to just keep updating here.

OK. I did the compression check. I almost dirtied my pants when the cylinder hit the first compression stroke....200 lbs of compression!!!:eek: I was not expecting much over half of this and was unable to hold the gauge in the hole and it came out, propelled by 200 pounds of air pressure, and I landed on my hind parts. The battery I had was losing charge and the numbers dropped to 180 across the board on the second try.

I don't have to pull the heads! YAY!!!! This makes me feel so much better. I was worried I would have to stick a ton of money into gaskets. I might be able to get away with just replacing the valve cover gaskets.

I am not sure how much more I will get done today. My brother called and said he bent one of the i-beams on his truck.....turns out he got stuck in dad's field and instead of asking dad for some help, he got the neighbor to help. They used a chain and got some good running starts:eek: He is coming over to have me look at it and maybe put a new front end in his truck....:(

The final drive on the 4t60 was 2.84.
I just found out the final drive on the 4t40 is 3.91.
You can see where this leaves me.

Instead of turning 1500 rpm at 55 I will be turning 2000.
and while I was doing 1750 at 65, I will be doing 2500.

What is this going to do to my mileage?.:confused: Granted, I could climb a mountain in 4th gear...but still. OH, and the transmission shifts in the opposite order!!(4-3-2-1):eek: what gives?

I might have to see if the 4t60 will fit.

I suspect it'll pretty much negate the purpose of doing the swap (from the fuel economy perspective). Have you or anyone ever done a gear vs. fuel consumption chart for that drivetrain? eg:

http://www.metrompg.com/posts/photos...-rpm-mpg-z.gif

( from: Showdown: testing RPM vs. MPG at a fixed speed - MetroMPG.com )

If anything, you should be gearing the V6 drivetrain to spin at even lower RPM than it did in the Olds, since you'll be pulling less car around behind it. That would be the only reason I would attempt this swap, personally!

I didn't have his exact year but on the buick 3800 that would be like driving in 3rd versus 4th and fuel consumption skyrockets above 1500 RPMs from about 40mpg down to about 25mpg 1500-2000rpm

I believe he might be best going to a local transmission place that is willing to work with yah so to say and get a final drive swap done.

I would think a 2.73 would work best, maybe even a 2.5

Cheers
Ryan

I talked to a guy today who makes limited slip diffs for fwd. He said he can send me a set of overdrive sprockets that would give me a final drive of 2.53 for $200.

I also asked about his limited slip diff, and he said that would be $600. It would be nice to have a limited slip diff in the snow and off road.:thumbup:

2.53... going to do it?

$200 is definatley worth conservatively 5-8mpg better on the road I would say.

The trouble is this will sno ball, because you now need a shift kit (or need to rig the transmission yourself) to ensure it locks up at lower RPMs.
You also will get a chance to do a lite rehaul of your transaxle which may be worthwhile. (seals, boots, bushings, outer bearings)

This will definately be an interesting conversion.

Good Luck

I don't know if I am going to do it or not right now.:confused:

The rpm difference, I can live with if I have to. I just need a car.
I have been looking over the schematics for these transmissions and noticed that the shift pattern on the 4t40 is only half backwards.

The A solenoid is used the same on both. It is the B solenoid that is switched backwards. All I have to do is put a PNP transistor in the solenoid wire and it will do the exact opposite.

I have also thought about using the 4t60 if I can splice the CV shafts. I am going to take the inboard end from the 4t60 shaft and put it on the 4t40 shaft and see if it fits. If it does then I will use the 4t60.

The axle parts won't swap.:( They have two different carriers.

I will have to use the 4t40 and alter the B solenoid wiring so it does the opposite of what the PCM tells it to.

If you have the skills and the patience, get it working right (it looks like you did)

and you can always go back in there later and drop in a final gear swap.

Although trust me, once its done and working its hard to go back in.

The fuel savings from going from a stump puller to an airplane can be rather large.

The FE difference on my buick at basically every speed comparing 3 to 4 was massive, at higher speeds I lost about 40%

Spinning that big brick comes at a price, hopefully you mainly want this car as a town hopper and it won't be too bad for that.

If you do venture on the highway get a fuel economy guage of some sort, I would guess 40-50mph will be your sweet spot.

This may be one of those oddball situations where big tires would save fuel, if you want to scrap out the wheelwells and find some light 19" or 20" wheels

Sadly 20" wheels cost more than the final though :(

Good Luck and keep us posted.

I am not really sure what I can do with the final drive right now. It seems that is the lowest I can go. I will call a tranny shop and find out for sure. It sure would be fast. I could always sell it for $$$$ and get a fuel sipper.:D

I have a guy looking into the final drive on the 4t40. He thinks he can get it down to 2.87ish, which would be perfect. I will be installing a few new components in the tranny to make it hold up to the power.

He also told me that I can use a 5 pin bosch NC relay to drive the B solenoid.

YAY!!!

Sounds good, with that big of a motor the higher you get geared (numerically lower) the better, assuming you do not loose lockup, so anything in the 2.5-2.8 range is probably going to work out well.

Good Luck
Ryan

3800 sunfire update
 

I have done a lot of figuring over the winter and started working on the car again today. Not much, just getting my bearings again....LOL

I am looking for any ideas on the gearing. I have to get a new chain and sprockets to handle the extra power, so the mileage won't be too bad to start with.

Current gearing: 3.91
New chain/sprockets: 3.05 should be a huge improvement
New diff: 2.54 $1000+

Would it even be worth it to mess with the diff?

at a thousand bucks? No.

Why such a big engine in a sunfire? Isn't that a cavalier?

Chain and sprockets?
For a moment I thought maybe it was a motorcycle, or a project car with a motorcycle drivetrain.

Your car's page:
Details: 3800 Sunfire - 2002 Pontiac Sunfire Fuel Economy - EcoModder.com

Anyway, I don't see how swapping in a 3800 cc engine to replace a 2200 cc engine will improve fuel economy. Unless its actually a performance project and you just want to make some effort to keep it from becoming a total fuel hog. In which case you may be on to something.

But what are the chain and sprockets?? I don't think you'd be changing the gear ratios of a timing chain. It must be something else.

Isn't there a thread about your project already?

It makes more sense to post your updates there than to start a new thread. Post the link and I'll move these posts over, if you like.

http://ecomodder.com/forum/showthrea...wap-20678.html


the 4 banger in the sunfire was a piece of crap. All I was doing was fixing it and it never wanted to run. The 3800 gets good mileage and has plenty of power and I already have it.

FWD transmissions have chain/sprockets on the input side. They have to, to get the gears away from the crank axis. If you have a FWD, look into changing the chain and sprockets to a different ratio.

If I got 36 in the olds then it should be about the same in the sunfire. It weighs 800 lbs less and is more aerodynamic. Yeah, it'll be fast. That means I can get out of the way quicker. The old 4 banger got about 25 mpg with the gearing and high stall. The new converter has a 1420 stall and the gearing will be brought down and that should give me some decent mileage numbers to work with. I can always gear it down more later or put taller tires on it.

+1 on the 2.2 being really crap. I had a buddy with a 2.2 Cavalier and whenever we'd go places, he ask if we could drive my car (Ford Taurus SHO) because it would in fact get 2-3 mpg better. Not to mention I had twice the power, more space, better ride, more accessories etc.

I'll be blunt, I loathe GM for the most part. But there are a few things I like about them, and the 3800 is definitely one of them. That and the LS motors. 3800 is a great engine, no doubt about that. I can't imagine what a Sunfire would be like with one of those, :D

I think it will be a lot of fun. I have seen a few vids on youtube of cavaliers with 3800's and they are FAST. I don't really care how fast it is, just so long as it goes when I want it to. I am trying to make the 4t60 fit because it will save a lot of money. The only thing I need to do is check the fit of the axle shafts. I will do that in the morning. It will be a little while, but I will post a video when it is done.

I was just looking over the gear combinations and I can get an overdrive chain/sprockets for the input side and drop the final drive from a 2.84 to a 2.53.

I am wondering what this would do to my power in high gear.

The gearing would be as follows:

55 mph 65 mph
current gearing 1428 1687
new gearing 1272 1503

I am thinking a gear swap would put me too low on the power curve. I would literally be idling down the road. I don't want it to downshift to go up every hill do I?

Don't tell me I did it wrong, I know I didn't follow the directions, but the air is attached on the rear window, so i am going to use the window as a starting point.
I was messing around with the aero template and came up with this:
Attachment 12779 I will remove the spoiler and put a sharp edge around the back of the car for clean separation. What do you think?

Don't be afraid of a downshift. In this situation, I think it's a good thing.

At highway speeds, you pretty much want the engine running at low rpm so it's at maybe 60-70% load when cruising. Not super light throttle and 25% load, that would give you some engine braking constantly. The high loading puts you in the good part of the BSFC chart. Since it's running at kinda close to maximum output for its rpm, you will need more power if you want to maintain speed on a significant upgrade, or for acceleration. So you'll need a downshift for that.

If you don't need a downshift, you're running a lot more engine and/or a lot more rpms than you need. And your fuel economy will suffer.

Shucks, its an automatic. It will downshift for you. Now worries! With the tall gearing, the downshift won't bring the huge fuel economy penalty it would on a "normal" automatic.

Swaping sprockets would be like driving into a 10 mph head wind with a 250 lb passenger.

WOOOOOOOT!!! IT FITS!!!!

After sitting all winter in a snowbank, I pulled the 4t60 out of the olds just to make sure it was the wrong spline count on the shaft. The reason I thought the shafts were different is because 3 transmission shops said they wouldn't fit and so did the parts info at the auto stores. I thought I was screwed. NOT! I stuck the stub shaft from the 4t40 in there and it fits on both ends. All I have to do is get different seals. I did not have the time to check last year to see if it really would fit. Not only will the shafts fit in the transmission, but I can use the entire sub frame and weld/bolt it right to the bottom of the sunfire, saving LOADS of time, money, and parts.

This is going to be awesome! Maybe you can't tell, but I am stoked. This is going to be a LOT easier than I thought. If I would have known this in the first place, I would have pulled the entire unit out of the olds and stuck it in the sunfire and would have been driving it all winter. At least now the motor and transmission can get a good cleaning, paint, new seals/gaskets, and new fluid before going in.

The gearing will stay at 2.84 for the time being. I can always change it later.
I will use the dogbones from the caddy for upper torque mounts. That should keep things from moving around in there.

If anyone wants to do a swap like this, the part numbers for the new axle seals are 710158 and 324204. These are National Seal numbers. It will be necessary to use the shaft sleeves from the sunfire. The shafts will pop right in.:D

Just the other day, I was telling the girlfriend about people taking the 3.8L Supercharged out of my Regal GS and putting it in the 1996-98 Grand Ams. But in a SUNFIRE?! If you were a speed racer kind of guy, you'd be on to something pretty fun there.

I know yours isn't the Supercharged variety, but you could consider it later. I routinely got 33-35MPG in my Regal with five adults in the car. Minus their 800 pounds, and all the luxuries (power leather, dual climate, etc) I'd imagine a Sunfire would achieve great MPG with the 3800.

Looking forward to pic and video updates!