2-3 is crap, no matter what.

it makes a huge difference to have a nice broad power band, that's for sure. there are lots of gear ratio calculators out there, so figure what your end goal is for ratios depending what tranny you'll be going with. I personally think 3.54 is best all around, go higher if you're racing, or lower if you just want a highway cruiser (or just get a taller 5th).

Not sure about what parts to swap, though I think just doing the guts is easiest. Matt did mine (thanks again Matt!), so hopefully he or one of the more esperiensed guys will chime in.

Just for an idea (and the final drive ratio on the M41 is close enough to the M46) the Canuck with 3.73 gears turns 2450 rpm at 110 KPH - which is very relaxed on the highway. So 3.54's would be a great choice for a balance of speed and cruising. You're not going to be melting the tires with ease, but that isn't the goal (or is it ). If it were me doing it, I would just swap the axle not the innards. If you swap the inners, then you'll have to replace all the bearings (cause you'll likely bugger them up and it's just a good idea) and seals.

The rear end in the YROG is pretty crunchy, so this is a DO IT sort of thing. I'd get all the adjustable IPD stuff as it fits the goals of your car and you won't find them for a better price (and it would be less stuff to pull). Leave Athal with your old axle for when the 242 gets retired.

I don't think the final drives can be that close! With the 3.73, I was at ~115 at 3000rpm. with the 3.54, it's closer to 120 at that rpm.

One online calc say's you'd need a 0.7:1 top gear with a 3.73 rear end to hit that. Or a 0.8 fifth with a 3.31 rear end...or ALOT bigger tires than me...

What size tires have you got on that thing, Craig? That sounds really slow - with 215/45x17 at that gear ratio, you should be turning about 300 rpm faster than that. That's about what to expect with a 3.31... The M41 is around a 0.79:1 final drive, isn't it?


Edit - I was typing all the following junk while Athal was posting.
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I used to run 3.31 gears and have found that with the M46 they worked REALLY well with a turbo engine and small flywheel. The 244 had these gears with a B23FT and the 740 had these gears with the B230FT. With the heavy flywheel behind the B230, it's REALLY important to not rely on the engine revving too quickly. Even with the flat 8.5" flywheel in the 244, I liked the 3.31 better than the 3.91, 3.73, and 3.54 gears I tried in it (well, not in IT, but in the 242 this is what I settled on so stuck with it in the 244). In either case, accelerating a turbo engine too quickly just lets the engine get away from the turbo too much, and you don't end up making boost 'till you're right near redline.

Now, going forward, if you plan on putting a taller 1st gear in there (like a 3.35:1 in the Mustang T5, for example) the 3.31 final drive makes approximately 10 kph at a 900 RPM idle. It sucks in rush hour downtown Calgary traffic 'cause traffic never seems to move that fast, but in your neck of the woods it would probably be okay. It would take you to over 60 kph in 1st gear, so you'll be scooting before you need to change gears.

However, if you leave 5th gear alone in the Mustang T5, a 3.31 is NOT what you want! You'll be cruising at about 2100 RPM in 5th gear at 110 kph, and it takes a pretty torquey engine to haul that around. Even with a 4.10 final drive you're looking at just under 2600 RPM, and on a top end engine that's not very fast.

For the 780 I'm planning on using a 3.73 final drive ('cause it's there) and a T5 with a 0.80 fifth gear conversion. That gives me snappy off-the-line acceleration and close ratios right to redline in 5th, and a cruise RPM of just under 2800 RPM. I don't cruise on the highway as fast as you do, though, so for 140 kph cruises you might want to drop down to the 3.54 gears for this transmission.

These are all examples just to get you thinking, Greg. Personally I think the 3.54 would be nice for whatever you do, and I wouldn't worry about changing it until it becomes a problem for you. Between the 3.54 and 3.73, you probably won't even notice the difference unless you're REALLY looking for it, and when you swap transmissions and find that it's really a problem, deal with it then. Don't get ahead of yourself.

Yeah, okay, cool. Thanks guys for the responses. This is all starting to sound good. I certainly don't need tire melting abilities, but you're right Matt, cruising at 140 comfortably is more of a priority. I hadn't thought about building boost in lower gears, but yeah, that makes sense....taller gears there would be better. Excellent. Me like.

If I remember correctly, I'm at just under 120 at 3000 rpm with my 3.73, so about the same as Athal. Dropping that down a notch would be great for anything over 120. Zis is good! I'd like to be able to get over 200 as well, and I'm just shy of that now.

So, Athal....if you're down, lets doo eet. What's your preference for swapping? Does an axle swap interest you at all? I'd pull the one off YROG here, drive it up, swap it over so you're still rolling, and come home. I'll have to see if there's any other bits I need when I'm there as well.

Sorry I've taken over this thread.....

I think we can do that swapperoo Greg. I still haven't totally decided what I'm doing, but the registration expires this weekend and there's no point in renewing it.
Damn, I have to get the 940 on the road so I can get the 242 off the street!
I'm still searching for a worthy donor, for at least the engine. Now thinking a clean 740T would be the way to go, at least from a price and availability standpoint, alot more likely to find one with a blown motor anyway! Too bad that white 240 wagon was sold, damn.
Even if I decide to swap everything over to another 240, i'll be ok without the LSD (and extra work to swap it), and happy that you can enjoy it.

The tires are 205/50 17's (for 25.1" diameter) and the final ratio of the M41 is 0.77. This gives me with 3.73 gears: 2150 rpm at 55 MPH, 2400 rpm at 62 MPH, 2600 rpm at 68 MPH, 2880 rpm at 75 MPH, and at 85 MPH it is doing a paltry 3260 rpm. I found this on an online calculator and all of the speeds and RPM's were logged during the shake down cruise. There is a pretty big drop between 4th and OD in the M41 of course it depends on speed, but at 55 it will take almost 400 rpm and at 85 mph it knocks almost a grand out of the engine speed.

Hmmm...I know of a dark green one that will be missing an engine shortly and is pristine compared to the 242...

Sweet! Thanks dude! I've been hoping to get one for quite a while, so this is the sweetness for me.

I got thinking about other 240s for you, and remembered that one (blue?) later 240 wagon I posted a while back. It was still up last time I checked, but I couldn't find the link again. It looked pretty nice if I remember correctly.

Now I guess we'll just have to figure out a weekend that works for both of us. I'll be in touch about that. I may have to do an inventory check in the garage to see if there's anything else I should be grabbing off that car.

Yeah, but it'll be missing things like a windshield, rear subframe, brakes, pedals, headlights... Almost all of which is negotiable for the right buyer, of course.

BUMP!

Rear end is gone, seats are gone, everything else is available. Now that the process is started, I'll be wanting the leftovers moved as soon as I'm done pulling the engine.
If you mentioned interest in parts before, speak up and let me know if you still want stuff!

have you any go fast bits still?

I'm expressing interest in stuff too, I think. (bottom end, if you are willing to separate at any given time )

bump

trevor was going to take everything, but now can't decide.

not parting out the motor, but pretty much everything else is up for grabs. CVC gets first dibs before i update the tbricks thread (which I said everything was sold yesterday).

I'd rather work something out with you local guys than have to ship!

good on you, may drop by sometime soon then. Im up in crecent heights again so im just a few away.