Help me spend my money (Mazda5 swap)

Intro

I'm giving some serious consideration to dropping a 5 speed ALH into a early Mazda5. I recently took my Beetle with my wife, 2 kids and a small 4x7 Uhaul open trailer loaded with a piano and a bunch of other stuff from Missouri to Ontario (13 hours) and the car did surprisingly well. I estimate I had 1300 lbs including the trailer behind me, plus 500 pounds including occupants in the car.

Base curb weight of my car is 2867lbs, which puts my total weight for that trip at 4667lbs. I was driving 72-75 most of the way home and averaged high 30s.

A Mazda5 weighs 3400lbs and should be more aerodynamic and have less rolling resistance than my Beetle towing a trailer so I have expectations of right around 40 mpgs. That would put a smile on my face.

One thing I'd need (eventually), is a bit more power. The car loaded was quite happy to go 60, a bit grumpy going 70 and felt near maxed out around 80. I like traveling at 77-78.

My car is 100% stock. If I go ahead with the swap, I'm leaning towards a Malone Stage 1 tune and 205 injectors. I might swap in a 11mm pump too.

The Money Spending Part

Clutch: What do I go with? I'm hoping to have my wife confident driving standard in the next month or so, so I'd like something that is easy to drive but that I'm not going to be replacing on a regular basis. Any suggestions?

Transmission: I haven't looked at ratios yet but I'd like something with a shorter 1st. All the other gears seemed fine while towing. I imagine the easiest thing to do will be to swap 1st gear. Any idea on a common transmission with a taller 1st? I'd probably bump second up a bit too just to narrow the gap.

Axles: I'm planning on getting a local shop to splice the Mazda and VW axles together at the correct length. Anyone ever done this before and have any insights? The other idea, is to find a wheel bearing that would fit in the Mazda knuckle and fit the VW hub in the center. I know VW offers some different length axles so I might be able to make something work. I haven't gotten under a Mazda5 yet, but I think the front track width is pretty close to my Beetle. Anyone have links to bearing sizing? I'd run steel rims and hub caps to hide the different bolt pattern.

Immobilizer: Can someone confirm that the 99 Beetle does not have an immobilizer? I don't see any dash lights that look like the immobilizer symbol on mine.

Clutch Master/Slave: If I use the Mazda master with the VW slave cylinder am I going to run into issues? What do I need to check and how do I do it?

What else am I missing?

I'm a bit short on understanding what the real reason is for this. Golfs and Jettas (especially wagons) are more aerodynamic than Beetles. A good clutch and a Stage 2 tune along with .205 nozzles and you've got a pretty good power+FE combo: this is what I've got going on in three of my Golfs.

Conversions and such are fine as long as something doesn't go bad/wrong, at which point there may not be many people willing to touch the vehicle. While I tend to almost all the work on my cars I realize that there may be a time in which I won't be able to do some necessary repair (either due to age/ability or because the car is not within range- the later is an issue I struggle with for the daughter's wagon [it has a competent TDI mechanic available close to where the daughter lives]).

Sliding doors is the reason. We are expecting our third in September, which will be 3 in car seats.

I'm a mechanic so I'm not worried about finding someone to work on it. I'm hoping for 4-6 years of daily mom-duty service from this van, then I'll probably drive it into the ground. After that the Pacifica hybrid is looking pretty tempting but I know the landscape will change a lot in the next few years.

I'll start off by saying this swap is a good idea and has already been done: http://forums.tdiclub.com/showthread.php?t=414563

As I stated in that thread, you'll want to carry over the mk4 mounts and fabricate supports for them.

If I were planning on towing anything I would go for more than a stage 1 tune. If you stick with stage 1 then you have more clutch options and I would go with the sachs quiet clutch. If you go beyond that the southbend would be the way to go imo.

Axles: just have your shop make you a custom shaft which has the TDI inner joint and the mazda5 outer joint, at your necessary lengths. Easy peasy.

Yes, I believe the 99 beetle will not have an immobilizer. Regardless you can get it deleted when you get your tune.

I would keep the mazda5 radiator package (rad, condenser, fans, etc) in place and just plumb to them. I would however use the VW fan controller as it interfaces seamlessly with the vw ecu.

In my mind the intercooler is the one item which is open for me. if you can make a SMIC work I would go with that for simplicity's sake. Otherwise, I would do a FMIC.

Sounds like a cool project. Be sure you post your progress!

Good comments so far. I guess you will be towing a lot. Otherwise I would stay with the standard gearing.
No immobilizer in '99.
I like /uhOh's combo- A good clutch and a Stage 2 tune along with .205 nozzles

If you're towing with a tuned car I'd make damn sure to have an EGT gauge..... It's pretty easy to get in EGT trouble when towing on a turbo car, especially when pulling hills.

I'm not planning on towing. Long road trips would probably require a rooftop carrier but that would be all.

The reason I mentioned a shorter first is because I find my Beetle easy enough to stall and it will be significantly worse with an extra 1000lb of car to move every time.

Thank you for the link. I've read that thread before but it's nice to have it here for easy reference. It's too bad he used the 1Z.

I've read the 5th speed swap is fairly easy, I'm guessing 1st swap would not be. Plus the stall point may feel completely different with different clutch.

i don't think you'll find a shorter first for the 02j but you could swap in a trans from an awp 1.8t and put in a taller fifth ... the awp equipped cars had the tallest ring and pinion for a 02J behind the tdi geared trans... this would get you a lower gear stack and help with getting up to speed ...sorry i can't recall the exact trans code for that particular car but easy enough to locate

I just spent some time looking at ratios and it looks like if I go with the EHA (from a AWP 1.8T) R&P and use first from the TDI DQY transmission at 900 RPM I'd drop 1 kmph. Problem would be on the highway using the DQY fifth with the EHA I'd be spinning 2907 rpm at 75 mph compared to 2576 rpm with the stock DQY transmission. Looking at the numbers I think I'll just keep the transmission stock.

Regarding clutches, is the DMF easier to drive than a SMF? Will the stock one happily handle Stage 1 and 205s with an extra 1000 lbs being moved? I'd be willing to drop either Stage 1 or the 205s from my upgrade list if the DMF was easier to drive.

I appreciate all the input so far.

you can't just swap first gear, you have to use at least first and second of whatever mainshaft you choose... you're also not stuck with a stock tdi fifth but can go taller ...how about an ERR six speed from a turbo s beetle ? on the dmf vs smf ... the dmf can be slightly smoother and a 17-050 LUK (5 speed only) holds plenty of torque for most moderate builds and is cheap

Stock 02J and power mods make 1st almost unusable. I don't see any need for a lower gearing (with mods). I regularly haul about 500 lbs of feed in the back of my Golf (and my spare Golf) and it's barely noticeable. I suppose that as has been mentioned, a 6spd out of a gasser might be a viable option.

Oh yeah, I'd read "Mazda6," which is why I was puzzling. A Mazda5 is totally different (and more understandable). My wife used to have a Mazda5; got it new and the stock suspension was really crap in a very short period of time. I never wanted to touch that car: not much room in the engine compartment; a TDI is going to be better, though not sure how much so.

burn_your_money said:

Regarding clutches, is the DMF easier to drive than a SMF? Will the stock one happily handle Stage 1 and 205s with an extra 1000 lbs being moved? I'd be willing to drop either Stage 1 or the 205s from my upgrade list if the DMF was easier to drive.

Click to expand...

On the stock Sachs clutch and mods, NO.

With just DLC1019s in my ALH and the stock clutch, with the IQ tuned for maximum output (and stable idle, etc) I can just slip the stock (Sachs) clutch in 5th. That is NO other mods; stock ECU code. When I gave the car to my kid I turned it down a bit so it was no longer possible to slip it in 5th as she was a fairly new driver at the time and I didn't feel like doing a clutch job a month later. It's now more than three years down the road and the OE clutch is still serviceable.

The LUK RepSet would probably hold 205s and a Stage 1 tune, and is a DMF. The issue isn't so much the extra load as it is the maximum torque of the engine and whether the clutch will hold that. Load being moved (whether pulled or in the vehicle) and whether the clutch withstands that is more a function of driving technique than anything else, just as is clutch life generally, provided the clutch does not slip when fully engaged and the engine is at maximum torque output.

Lukj 17-050 is holding a Stage 2 Malone tune and DLC520s in my wife's car. This is pushing it though.

I had DLC520s and a Stage 1.5 Malone tune in my car and my stock clutch held fine. But, when I switched over to a Stage 2 Malone tune (I got the 1.5 and 2 at the same time, on a Flashzilla) the clutch screamed "Uncle!"

Good info, thank you everyone.

That's a good thought on mods making 1st gear even easier. With that in mind there really is no benefit to swapping the gears around.

Ultimately, I don't want to spend any money doing this swap. But more than that, I don't want to have to redo something (especially the clutch) soon after completing the swap because I should have spent the money. All that to say, no 6 speeds.

So I've given this more thought and discussion with my wife and I've decided to scrap the 5 idea and instead go with a 05ish Odyssey. Way heavier at 4378lbs but I think I can make it work. I've driven Citroen Jumpys before and they are powered by a 1.6 or a 1.9l diesel and weigh about the same.

I need to spend some time under the hood of an Odyssey but I'm pretty sure I'll be using a 1Z engine instead. Definitely going to put a VNT on it though.

Now I just need to come up with an in-between car because I know I won't get this done before #3 arrives and the Beetle only seats 4.