todddchi

iTrader: (3)

Not sure if this belongs here or in gears.

Well, I finally found a good donor axle and built up the courage to try and do an full axle swap on my own. Spent most of the whole day dropping my 2.73 4 channel and putting in the donor 3.42 axle / TA cover.

Reluctantly, I decided to give the Predator one last try.

First run I changed only gearing over to 3.42 (this works now in the newest predators), and guessed at downshift mphs of 30/60/90. Went out and ran...
- Speedo good
- 1-2 banging rev limiter
- Downshifts (kick-downs) totally hosed

2nd run I dropped the upshift rpms from 6000/5900/5900 to 5800 across the board. This fixed the rev limiter banging. I have no interest in running at higher revs, even if it is worth a tenth I just don't like it on stock internals.

But I am still having problems with the downshift points. It seems like the predator is off by the same ratio as the gears.

If I set 2-1 to happen up to 30mph, I can't get a kickdown unless it's like 24 or under, and so forth.

With some more trials, I've found it seems to be off by the ratio of the gears. Is this a bug in the Predator?

I think I can get the downshift kicks I want (~34/70/110) by just artificially setting high values in the predator, but this makes me nervous. I don't want something to get straigtened out and then find the car tries to downshift at those settings. To get the numbers above (34/70/110), I'll have to set the predator up at like 44/89/140.

Anyone know?

Tks.

todddchi

iTrader: (3)

Well, I have things up and working, though it requires totally incorrect settings on behalf of the predator.

All listed 1-2, 2-3, 3-4 and vice versa:

- Upshift RPM (5800, 5800, 5800) any higher and I get the rev limiter. According to the tach I am getting shifts right around 5700 or so, which is just fine by me. I have no interested in raising that.

- Upshift speed (50, 100, 160). This just needs to be high enough as the WOT upshift is determined by the RPM setting rather than this. The 160 setting is locked in the predator for some reason.

- Downshift speed (45, 90, 140). This gets me real world kick downs at 35 and 70. I haven't been able to verify that the 140 will get me a 4-3 kickdown at the desired 105 or so.

It seems the predator downshift settings are in fact off by the same scale as the gear change. Not sure why this is but at least it's working.

I get a little pop sometimes right at the 1-2 shift. I believe this to be due to the engine reduction at the shift. Can anyone verify?

Also, not setting the WOT mph high enough resulted in the trans getting all confused and kicking down/up/down/grabbing all nuts like. Just put the mph settings way about like I did and it's fine.

-Todd

Charlie@LsXperts

iTrader: (12)

off topic but does the 2:73 to 3:42 change make a worthwhile difference cause im about to do the same

whatsaholden

iTrader: (1)

get a real tuning program, no offense.

todddchi

iTrader: (3)

Conventional wisdom says that a converter is a better investment. But a converter can cost more than 1k by the time you figure in tuning, a cooler, and the converter itself. I didn't like that price point, nor did I like the idea of tuning problems and installation problems. Nobody warranties aftermarket performance stuff.

Far as doing gears in the normal fashion, this is also a bad idea. Since you hae 2.73's, you'll need a new carrier. Lots of money if you buy new, and again regardless you have new setup issues and can end up with a whining or badly setup diff. Same situation, same 1k+ total costs.

Doing the whole rear axle swap is tons cheaper and avoids all the setup/tuning issues if you can find what you know to be a good axle.

Personally, I took the good with the bad on the 2.73's. I hated that it was hard to do a burnout, I hated the doggy launches, and low pull from a street roll. But I loved the mileage, the quiet 2k rpm 80mph cruising, and also the ability to get a 2nd gear kickdown going 80 on the highway to cut around ******** as it runs up to 95 or so in second.

If you are all highway, keep em.

But the 3.42's make the car a whole different animal around town and driving hard. 1-2 happens at ~40 instead of 50. Kickdowns happen at 35 and 70, both good ranges for rolls and highway speeds. I still have good traction at launch on good roads, and can get some bark on the 2-1 kickdown and 1-2 shift.

So for me being that the car is a bit of a toy, I love it, no regrets. I can't yet speak of mileage, and 2500rpm at 80 is definitely louder. I wouldn't want that with a loud exhaust.

I just posted my thoughts in a write up thread.

todddchi

iTrader: (3)

Well, honestly your statement is inherently offensive, a total dick statement.

The predator was $75. Of course tuning software is better but the fact is that has nothing to do with my topic. My topic was asking for help with the Predator, and then trying to help other people who might have the same problem.

You coming in and saying, "get a real tuning program" is a total troll move.