Changing Gears In A Manual T

[turbocorty]

Hi Sixrt,

I need to correct my original post, I thought it had fixed it by removing the switch - thus tricking the pcm...And for some reason on the way home from work, there was no power loss between gear changes. This resulted in 5 or so axel tramp chirps changing into second...then...on the next drive, back to o single chirp followed by power loss for a second and then away we go. SO the clutch switch does F-ALL.

There is no way the turbo spools down during my gear changes. I even tried doing a "lazy" flat change at around 3000rpm which used to result in a nice power slide in the VXSS...In the F6 case...a few chirps and power loss.

If this issue is resolved, the F6 with easily run 13'zzz no worries.

Cheers

[RAPHOON]

Don't think it's footwork. I wonder if the guys with custom tunes have this issue. Anyone?

[Guest Rota_Motor]

I just want to add, I think it is just good old fashioned turbo lag, anyone watched the boost guage as it happens, to see whats going on in the manifold?

remember you need to spool a turbo up, not like a N/A V8 or supercharged V6 or whatever.

I noticed it in glens T when he first got it, but he seems to have adapted... I also get it anytime I need to drive a turbo car at work and havent for a while.

Edited 09/06/05 09:24 AM by Rota_Motor

[Venom XR6]

It probably cuts the power totally between shifts as a way of saving the clutch. Ford used to do this with the autos in the T series cars to make it easier on them during shifts. Basically it would be a torque tag, an edit should be able to get rid of it.

[YOOT]

I have experienced the lag as well, I am pretty sure its just turbo lag, and if you falt shift you won't have it. My best changes see the clutch take up the full brunt of the gear change and the car just settles hard on the gear change and continues to rocket.

If I am too slow on the throttle (when I flat change I lift off 1/4) I can lose the boost and you get the hesitation for a second and the bang instance torque. Definately turbo lag. But you wouldn' realy notice it on the 6-4psi factory map. Middle to top end the factory map only makes around 4psi. When your making 2-3 times that boost, its not instant.

[turbocorty]

there is no way that turbo lag is responsible for this. I have owned and driven a few turbo cars over the years and non of them lost boost during a flat change..If anything boost would instantly rise due to the extra load. At 5000rpm full throtle lag is almost non existant due to the volume of exhaust flowing through.

One day I will monitor the throttle body signals and see if our friends at ford have put in some "anti-fun" algorithm into the PCM.

Time will tell.

[Turbo6man]

I noticed the delay/lag when I drove Cro's car around Wakefield. There was definitely a delay in power application with every gearchange that I have never experienced with my old turboed 4.1 litre. And my gearchanges are NOT slow. However I don't flat change, so cannot say whether it is a torque tag in the PCM or just turbo lag that I experienced. I'd suspect a torque tag. The guys who have "edit" should be able to clarify it for us.

[mickq]

Guys it sounds like torque tags.

The ECU is programmed with a bunch of stuff, including that under certain conditions it should limit engine power to prevent too much torque going through the drivetrain in those situations.

Attempts to flat-change from 2nd to 3rd may qualify as such a situation.

Im not sure why you want to flat change anyway? There is no real turbo lag at anything above 2500rpm and the car has oodles of torque. Its not something you should need even in very hard street driving.

Are you double clutching? Try that just out of interest.

But I reckon its torque tags kicking in. I have had them kick in during a burnout (only once) in my Mk1, and the result was me flooring it, and a very frustrating slow drop in revs as the engine backed off to protect the driveline. No real power going through to the wheels. Felt like clutch slipping - but that's not what it was. (And yes, TC was off!)

If it is torque tags causing the problem, then I believe they can be turned off with an Edit. Your turbo ramp up speed can also be increased which helps too.

Edited 09/06/05 01:42 PM by mickq

[Aeron]

So this is why I have only ever had my XR6T chirp into 2nd once, even when giving it hell.

[Trough Lolly]

I have a slight power cut when in a gear and give it full accel and u can feel it restrict power about 70% just for a second and then BAM on it comes.... I thought it was just the electronic throttle control that might be doing it!