AWD ATX torque limited ?

[fastbikes76]

Hey guys,

I TT'd the wife's JDM awd atx which is running the W4A33 box with stock torque convertor. The box is running a shift kit and IPT end clutch kit.

Engine mods are

13t's
630cc injectors
Apexi afc
FMIC
Aeromotive 340lph pump
M20 fuel (20% methanol direct in tank)

The problem is the car although running very very well , didn't make the power we hoped/expected. I'm totally new to Atx's and from what I can see it's like the torque convertor doesn't lock up and bleeds the power or torque off. The torque climbs to the point of peak boost and then appears to bleed off in a solid straight line as if something is making it rather than lack of boost.

This car Is a mirror image of my black NA except I'm on smaller 11b's. At the same boost I made 430/530 where as this made 384/445 on bigger turbos.

I don't care about the numbers on the sheet or more Dyno arguments.. Graphs are loaded purely to see torque drop off vs boost and shape of curves.

Is there a way to ensure convertor locks up properly or a way to stop what I 'think' is happening ?

ImageUploadedByTapatalk1416670189.210276.jpg

ImageUploadedByTapatalk1416670206.714372.jpg

Regards
Elton


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[familyMAN]

Actually, probably about right. HP flattens and hold steady. At that boost level, the 11bs and 13ts would likely be at similar power levels as long as the boost doesn't drop off on the 11bs.

ATX will soak up power but makes up for it in perfect launches and perfect shifts.

Make sure you are also shifting with full line pressure with either a shift box to bypass the TCU or the kiggly blue wire mod.

[fastbikes76]

Actually, probably about right. HP flattens and hold steady. At that boost level, the 11bs and 13ts would likely be at similar power levels as long as the boost doesn't drop off on the 11bs.

ATX will soak up power but makes up for it in perfect launches and perfect shifts.

Make sure you are also shifting with full line pressure with either a shift box to bypass the TCU or the kiggly blue wire mod.

Cheers for the reply.

My main concern is the torque takes a dive yet the boost doesn't. Normally when the torque drops off like that its due to the tubs not producing any more boost ? I have a shift kit installed and setup as per IPT's recommendation, so i guess its running increased line pressure but not 100% line pressure ?

I also have an issue where it doesn't change into second quick enough on the 1/4 and pops off the limiter in first sometimes. I have ordered a shift box from Forcedfour and will be running paddle shift instead of toggle switches. Its the wifes car im dabbling with so need it to retain daily drivability as well as hold up a once a year track visit.

Would 100% line pressure make it shift better from first to second and lock up better ?

Many thanks

[familyMAN]

A forced four shift box can work manual where you pick the shift point or programmable by gear if you have a Plus or Color. You'll have to play with your shift points and possibly your engine rev limit to maximize your setup. Yes, a shift box gives you full line pressure shifts (awesome!)

Lock up is completely different. That's for low-load situations (cruise) to maximize efficiency and keep trans cool. Aftermarket billet converters for the transmissions don't even use a lock up.

For stock TCU controlled shifts, you may need to program it to shift earlier or just raise your engine rev limit.

Full line pressure shifts for WOT is the best for your trans though so blue wire mod or shift box when shifting WOT will help your clutch life. (Did I say awesome yet for full line pressure with shift kit?)

[fastbikes76]

ah ok, starting to make sense now. Totally new to the atx scene so fitting the shift kit was pretty daunting eough .

Yeah full line pressure sounds like what I need then..is it awesome ? I have the forcedfour lite which is the cheapy one coming. I will run it with paddle shifts so I can either run full auto of the TCU , or 'manual' via the paddle shifts. I guess that way she can drive as normal when not at the track, and have full pressure to smoke people off the line when needed.

It brake boosts nicely and will build around 14psi off the line..It stands up and spins all four quite nicely. According to the VBOX data I have it pulled 1.53G accel, my 11b manual pulled 1.03G and my LS2 G8 GT equivalent pulls around the same. Just shows how well the ATX gets going !!

[box]

10.5:1 is way too rich, on that fuel id be shooting for 11.7 - 11.9:1. Also it might be worth locking the torque converter when you're on the dyno.

[fastbikes76]

10.5:1 is way too rich, on that fuel id be shooting for 11.7 - 11.9:1. Also it might be worth locking the torque converter when you're on the dyno.

Yeah it's running rich as this was just the first shakedown to see how the conversion went. I still need to fine tune and lean out a fair bit.

How would I lock the TC for the dyno ? Is that what full line pressure would do ? Again I am a total noob to Atx's so learning by the minute.

Regards
Elton.



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[Chris@Rvengeperformance]

From what I have read it can break the torque convertor to lock it under WOT. Leaning it out isn't going to pickup a ton of power. Maybe 20WHP.

[donniekak]

If you are flaring on the 1-2 shift you're eating the clutches. Check your fluid for a change in color or smell. Full line pressure shifts don't let the clutches slip.

[fastbikes76]

What is 'flaring' ? I often hear the term but still not sure what it is.

This is a quick vid of a test I did when running wastegate boost. I don't know if you are able to hear the shifts and let me know if they good or bad ?

Thanks


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