auto trans converter lock-up..

[feral4mr2]

my auto has a electonicaly controlled conveter lock-up. it's activated by a soleniod, would this soleniod be activated by a voltage? like a switch?

is it possible to manualy turn on/off the converter lock-up via my own switch and can it harm the transmission if gears are changed with lock-up engaged?


thanks.

[chris davey]

don't know 4age autos but 1jz autos you can. You just run a 12v wire through a switch to the lockup wire. Hit the switch and it locks up. Should definitely not have it locked while changing gears.

Also, using it at WOT may cause the clutch to start slipping depending on how much power and the size of the clutch in the 4agze auto.

[mrshin]

Most likely if you apply power to that wire, the clutch will engage, but some autos already have a separate power wire and you ground that lockup wire instead. Just make sure you set it up so that the lockup disengages at full throttle, and zero throttle.

[feral4mr2]

oh ok, so lock-up isnt recomended for WOT situations.??

see when i go WOT from a standstill once it shifts to 2nd sometimes it is jumpy (lock-up engageing/dis engageing) for a bit then into 3rd same thing. so i was going to manualy engage the lock-up for a smoother run through the gears plus more HP direct to the trans/wheels.

thanks for your replies.

[Grega]

i'd also recommend a good trans cooler. if you start locking it up earlier than factory extra heat will be created in the trans. heat and trans = shorter lifespan.

[feral4mr2]

sorry for not following up your replies guy's, i've had no internet connection out on site at work.

grega, the car has a stock w2o cooler for the transmission.

from the other posts i gather the convertor lock up is better to leave dis-engaged? for WOT floggings and things like dyno runs?
if so it sounds like i need to manualy switch it off, not on. as i posted before i do get it trying to engage and dis-engage when i'm in 3rd at WOT and i think sometimes in 2nd. so this obviously cannot be good for the transmission so i would be best to have a switch to manualy turn it off so it cannot engage and only allow it to engage when cruiseing (better fuel economy i beleive is acheived when cruiseing and convertor lock up engaged).

[mrshin]

Voltage switch from TPS to make sure it can't engage above about 85% throttle. What's controlling it now though, it should be like this anyway.

[Grega]

yep, like shinny says, disengage at like 65% throttle (the vn does this FYi)

(i've been fiddling around with locking up the TC on my VN to improve economy - the VS onwards lockup at very low kmh (like 72kmh) - the VN is supposed to do this but locks up at 92kmh instead - i'm manually locking it up as alot of driving i do is constant 70kmh crap - which *should* result in far better fuel consumption due to dropping revs by 600rpm)

(i also have a big cooler but i don't exactly have a stock trans (nor engine for that matter))

[too_quick]

I wouldn't have it on a manual switch, I know of a few people that have done it to vn and vp commodores and after a few months the clutch plates have warped and make a vibration when engaged, Let the ecu control it.

[1JZ-Rolla]

i'd also recommend a good trans cooler. if you start locking it up earlier than factory extra heat will be created in the trans. heat and trans = shorter lifespan.

I thought that having the clutch locking up earlier would create less heat, since the oil in the converter is not being thrashed around since its not relying on a fluid coupling to create drive? I know with my A3040LE that the quickest way to drop trans temp is to lock the converter.

oh ok, so lock-up isnt recomended for WOT situations.??

maybe not, but it seems reasonably commonplace for 1jz/2jz guys to lock the converter in third gear to get across the finish line at the drags, or do comparison dyno runs with the converter in the locked and unlocked positions. Anybody had one fail from this? I'd be interested to know if I should stop doing it now

(i've been fiddling around with locking up the TC on my VN to improve economy - the VS onwards lockup at very low kmh (like 72kmh) - the VN is supposed to do this but locks up at 92kmh instead - i'm manually locking it up as alot of driving i do is constant 70kmh crap - which *should* result in far better fuel consumption due to dropping revs by 600rpm)

Is your VN a V8? Cause my VS V6 ute struggles with the converter locked at 75kph and stupidly tall factory 3.08 diff gears. I wish I could stop it from locking at slow speeds, or get another diff [edit] or another car that's not a Holden haha

[mrshin]

The guys that put power through converter clutches have the converter altered beforehand.

[1JZ-Rolla]

Altered how? Mine has been opened to modify for higher stall, so its "altered", but i'm not sure if that's what you mean

[Grega]

some good discussion here ;

I wouldn't have it on a manual switch, I know of a few people that have done it to vn and vp commodores and after a few months the clutch plates have warped and make a vibration when engaged, Let the ecu control it.

agree ; i don't intend to run it manually ; but ; override it when i know i can do it (safely). i don't have a stock piece of shit thm700 remember - this can be done by jumping a couple of wires in the ALDL.

Is your VN a V8? Cause my VS V6 ute struggles with the converter locked at 75kph and stupidly tall factory 3.08 diff gears. I wish I could stop it from locking at slow speeds, or get another diff [edit] or another car that's not a Holden haha

nope............173rwkw V6......i don't have problems with my engine struggling per se and i sure as shit don't need shorter gears.....wheelspin can be a problem (when provoked). my missus stock as a rock VX V6 locks up at 72kmh and it rumbles a bit but is quick to unlock when a bit of pedal is applied...

Altered how? Mine has been opened to modify for higher stall, so its "altered", but i'm not sure if that's what you mean

i think shinny is referring to the vanes in the convertor being re-welded "properly" so they don't come off/the convertor come apart in different situations......that said i'm not an auto trans expert by any stretch of the imagination.

apologies for the all commodore talk.

[MS-75]

Altered how? Mine has been opened to modify for higher stall, so its "altered", but i'm not sure if that's what you mean

Altered meaning the friction area is increased in size, material chamged to Kevlar or similar and clamping force increased due to increased line pressure in the box.

Factory lock-ups are designed to only hold a fraction of peak power as they are only intended for use when cruising to increase fuel economy.

Sean

[1JZ-Rolla]

oops, I guess mine is gonna be fubared soon then