Manifold insulators problem/flaw?

[treyflip]

UPDATE!

Ok so I've changed all my coil packs and spark plugs and removed the spacers. I didnt have enough time to attempt to remove the snapped bolt but im certain its all sealed up. Unfortunately the flaw is still there (mine only happens in 2nd).
This problem pisses me off so much as i know exactly how to get it to happen every time and i have to drive a certain way so the car doesn't act like its having an orgasm .
It's most prominent at half throttle as soon as you change gears, when in gear for a while its not as bad but always happens under 1/2 to 2/3 load when changing from first to second at around 3000rpm.
To avoid it, changing first at around 3500 - 4000 seems to help alot.
At least thats confirmed it for me that its a factory fault in the gearbox tune? And im certain my friends 100% stock vz ute did it (only worse).
I can't notice much in the drivability yet of the car as I did reset the computer so I'll see if the spacers really made a big difference soon enough.

ATTENTION MACE: As i do like the idea of the spacers and they aren't causing any issues, could i just buy another gasket and use 2 gaskets (one on either side of the plenum and inlet manifold)?... as the RTV silicon has stolen countless hours of my life when trying to clean the damn thing when I break the seal.

[Zeussy]

Just throwing it out there, it might be worth bumping up the line pressures in the box, if anything just to help reduce any slippage - not too familiar with the 5 speeds, but I know the 4 speeds didn't like it when they were slipping???

Good luck with the issue, let us all know how it turns out..

[MACE]

ATTENTION MACE: As i do like the idea of the spacers and they aren't causing any issues, could i just buy another gasket and use 2 gaskets (one on either side of the plenum and inlet manifold)?... as the RTV silicon has stolen countless hours of my life when trying to clean the damn thing when I break the seal.

They shouldn't have taken hours to clean, all you need is a sharp long box cutter blade and away you go.

In saying this though you should be able to pickup gaskets from places like Repco, or Holden.

If you have any other questions please don't hesitate to ask.

Cheers,
Steve

[treyflip]

Thanks for the reply mace, so who or how can you adjust the line pressures??????????

[MACE]

Thanks for the reply mace, so who or how can you adjust the line pressures??????????

I don't know too much about these 5 speed boxes, best to talk to a local trans place. If you still get stuck let us know I'm sure something can be worked out.

Cheers,
Steve

[xxmrisaacxx]

I know in my vz sv6, when i had the car in power mode and just in drive, in about 3rd gear to 5th gear, under hard acceleration, it seems to slip and when i back off completely the revs just hover and it won't change gear straight away, but it helps if i take power mode off then it changes gear straight away. I've heard its a common issue, as you've guys said something to do with the torque management, but can be removed or improved by getting a tune, but thats only what i've read.

Btw my vz has only an exhaust mod, engine is stock.

Also a question for mace, i've heard you can't fit the mace insulators on with a cpr6, as it rubs on the Struct brace, Is this true?

Thanks

[Fishman88]

must the the 5speed auto gearbox. In my VZ calais this happens wen it was stock and tuned aswell. Its like the gearbox is partially locking up. Only happens in 2nd 3rd . 4th and 5th will be in overdrive so it locks up. It wasnt so noticable when it was on stock tune but once tuned was more noticeable. Try driving it in 2nd gear using the gear shifter not Active select and see what it does also try 3rd gear aswell. hope this helps somewhat. cheers

[impulsive]

I know in my vz sv6, when i had the car in power mode and just in drive, in about 3rd gear to 5th gear, under hard acceleration, it seems to slip and when i back off completely the revs just hover and it won't change gear straight away, but it helps if i take power mode off then it changes gear straight away. I've heard its a common issue, as you've guys said something to do with the torque management, but can be removed or improved by getting a tune, but thats only what i've read.

Fairly certain if the gearbox is holding it in gear longer, then its doign its job, only in the PWR mode though.. This is nothing to do with torque management, as the car, holding a lower gear with higher revs, would be allowing access to higher torque, especially at around 3000rpm. Max torque is at 2600 rpm am i correct?

[torana355]

must the the 5speed auto gearbox. In my VZ calais this happens wen it was stock and tuned aswell. Its like the gearbox is partially locking up. Only happens in 2nd 3rd . 4th and 5th will be in overdrive so it locks up. It wasnt so noticable when it was on stock tune but once tuned was more noticeable. Try driving it in 2nd gear using the gear shifter not Active select and see what it does also try 3rd gear aswell. hope this helps somewhat. cheers

Funny you say try it with the gear selector in L, i actually did this yesterday and the issue went away, as soon as i put it in drive and active select it did it again. This leads me to believe it is an Active select issue. I can also make the "jerk" happen higher up the rev range and with more force (revs drop even more) if i give it a bit more gas.

OP. Could you please try holding it in 3rd gear with active select then try and accelerate slowly from about 10kph to see if it skips? Mine does under those condition's in 2nd, 3rd and 4th gear, haven't tried 5th yet.

I think we can safely rule out the Manifold insulator as the cause of the problem.

[treyflip]

I think its safe to say its not the spacers. My car is running in tip top shape, snapped bolt is out, brand new coils and plugs, new gaskets, clean oil, and now back with the spacers on i can 100% confirm, if anything, the spacers helped smooth the problem! Funny as i thought they wouldn't make much of a difference down low but they really do! At full throttle there is definitely more torque and the car sounds deeper, (no miracles but still noticeable). Maybe it's due to all the other mods complimenting them, but they will be staying on!

OP. Could you please try holding it in 3rd gear with active select then try and accelerate slowly from about 10kph to see if it skips? Mine does under those condition's in 2nd, 3rd and 4th gear, haven't tried 5th yet.

I will tomorrow, i do know that my car pings in 4th and 5th in active select around 2000rpm when trying to take off a little if that helps?


torana355 how do the 3.46 diff gears cope with the auto gearbox? Im confused on how all the shift points still work properly if the gears are shorter?

[torana355]

torana355 how do the 3.46 diff gears cope with the auto gearbox? Im confused on how all the shift points still work properly if the gears are shorter?

Ok i will put it this way, Best mod ive done to my car by far, even better then the dyno tune!!! The Box handles the upshifts perfectly, the downshifts are fairly good too. First gear revs out really quick but does not put you in the seat much though second and third gear really plant you in the seat. You have to get your PCM recalibrated for the speedo to read correctly and for the L/100 to show a true value.

[Fishman88]

Funny you say try it with the gear selector in L, i actually did this yesterday and the issue went away, as soon as i put it in drive and active select it did it again. This leads me to believe it is an Active select issue. I can also make the "jerk" happen higher up the rev range and with more force (revs drop even more) if i give it a bit more gas.

OP. Could you please try holding it in 3rd gear with active select then try and accelerate slowly from about 10kph to see if it skips? Mine does under those condition's in 2nd, 3rd and 4th gear, haven't tried 5th yet.

I think we can safely rule out the Manifold insulator as the cause of the problem.

Yes i reckon we can rule out the manifiold insulators as the cause. Its the gearbox and i think theres not much we can do about it just the way its designed/built tuned..

[MACE]

I think its safe to say its not the spacers. My car is running in tip top shape, snapped bolt is out, brand new coils and plugs, new gaskets, clean oil, and now back with the spacers on i can 100% confirm, if anything, the spacers helped smooth the problem! Funny as i thought they wouldn't make much of a difference down low but they really do! At full throttle there is definitely more torque and the car sounds deeper, (no miracles but still noticeable). Maybe it's due to all the other mods complimenting them, but they will be staying on!

I will tomorrow, i do know that my car pings in 4th and 5th in active select around 2000rpm when trying to take off a little if that helps?

Well there you go, the spacers do work as advertised

In regards to gearbox calibration, which seems to be the problem here, the 5 speed auto is a bit of a orphan box amongst the GM family in that not many other vehicles use them besides our commodores. Even then only for certain upspec vehicles. Therefore I can see any calibration software coming out for these boxes anytime soon

In saying this though, it may still be possible to tweak the shifting characteristics by physically tweaking the box.

Hope this helps

Cheers,
Steve

[MACE]

I think its safe to say its not the spacers. My car is running in tip top shape, snapped bolt is out, brand new coils and plugs, new gaskets, clean oil, and now back with the spacers on i can 100% confirm, if anything, the spacers helped smooth the problem! Funny as i thought they wouldn't make much of a difference down low but they really do! At full throttle there is definitely more torque and the car sounds deeper, (no miracles but still noticeable). Maybe it's due to all the other mods complimenting them, but they will be staying on!

I will tomorrow, i do know that my car pings in 4th and 5th in active select around 2000rpm when trying to take off a little if that helps?

Well there you go, the spacers do work as advertised

In regards to gearbox calibration, which seems to be the problem here, the 5 speed auto is a bit of a orphan box amongst the GM family in that not many other vehicles use them besides our commodores. Even then only for certain upspec vehicles. Therefore I can see any calibration software coming out for these boxes anytime soon

In saying this though, it may still be possible to tweak the shifting characteristics by physically tweaking the box.

Hope this helps

Cheers,
Steve

P.S. If anyone finds a way of improving this please keep us posted as I would be interested to hear the outcome

[immortality]

Interesting to hear about the pinging in active select. Add some octane booster to a tank of 98ron and see what happens