"Problem" in 1st gear - SST
"Problem" in 1st gear - SST
Any SST guys run into something like this yet?
In 1st gear at WOT if I try to shift into 2nd the RPM's get held around 7200 and just hold there until I let off. It *will not* shift if I stay WOT and keep trying to shift. I have to let off before it will do anything.
It's a really weird experience as:
A. The throttle is not getting closed
B. The timing is not being retarded
C. The RPM's just get held
The car keeps moving it's just not really accelerating but it's not falling over as throttle nor spark nor fuel is being taken out...
From some other things I am logging it seems like the car is getting stuck in between 1st and 2nd gear in a weird no-mans land.
Something to note: If I *do not* try to shift and just let it hit the rev limiter in 1st, I can then shift into 2nd after it hits the rev limiter a couple times.
I had no issue with this until the car started making some "real" power after moving to E85 and BBX Lite.
I've been talking with somebody else about this and we might be on the road of solving it but I wanted to see if anyone else has experienced this yet.
Log:
- Bryan
In 1st gear at WOT if I try to shift into 2nd the RPM's get held around 7200 and just hold there until I let off. It *will not* shift if I stay WOT and keep trying to shift. I have to let off before it will do anything.
It's a really weird experience as:
A. The throttle is not getting closed
B. The timing is not being retarded
C. The RPM's just get held
The car keeps moving it's just not really accelerating but it's not falling over as throttle nor spark nor fuel is being taken out...
From some other things I am logging it seems like the car is getting stuck in between 1st and 2nd gear in a weird no-mans land.
Something to note: If I *do not* try to shift and just let it hit the rev limiter in 1st, I can then shift into 2nd after it hits the rev limiter a couple times.
I had no issue with this until the car started making some "real" power after moving to E85 and BBX Lite.
I've been talking with somebody else about this and we might be on the road of solving it but I wanted to see if anyone else has experienced this yet.
Log:
- Bryan
Last edited by GST Motorsports; Nov 12, 2010 at 11:24 AM.
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Joined: Dec 2007
Posts: 12
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From: Germany / Bavaria
I had the same Problem @ some SST. Still with stock Turbo and Engine.
When you start in S-Sport without LC it couldn´t catch the 7000 to shift. Revs to the Limiter 3 or 4 times and then you get the 2nd gear.
Funny thing. I tested it with exact the same Map and same setup on different cars. 50% of them had that problem.
What I realized is, that when the car has to much wheel spin at the launch, it couldn´t shift.
The only thing that helped was to reduce the Boost in 1st gear.
Got the Problem @ 400Bhp and 520NM@2900RPM (after midnight for me, don´t want to change the units). Solved it with less Boost from 2500 to 3500. Without wheel spin I didn´t get any problems.
When you start in S-Sport without LC it couldn´t catch the 7000 to shift. Revs to the Limiter 3 or 4 times and then you get the 2nd gear.
Funny thing. I tested it with exact the same Map and same setup on different cars. 50% of them had that problem.
What I realized is, that when the car has to much wheel spin at the launch, it couldn´t shift.
The only thing that helped was to reduce the Boost in 1st gear.
Got the Problem @ 400Bhp and 520NM@2900RPM (after midnight for me, don´t want to change the units). Solved it with less Boost from 2500 to 3500. Without wheel spin I didn´t get any problems.
I had the same Problem @ some SST. Still with stock Turbo and Engine.
When you start in S-Sport without LC it couldn´t catch the 7000 to shift. Revs to the Limiter 3 or 4 times and then you get the 2nd gear.
Funny thing. I tested it with exact the same Map and same setup on different cars. 50% of them had that problem.
What I realized is, that when the car has to much wheel spin at the launch, it couldn´t shift.
The only thing that helped was to reduce the Boost in 1st gear.
Got the Problem @ 400Bhp and 520NM@2900RPM (after midnight for me, don´t want to change the units). Solved it with less Boost from 2500 to 3500. Without wheel spin I didn´t get any problems.
When you start in S-Sport without LC it couldn´t catch the 7000 to shift. Revs to the Limiter 3 or 4 times and then you get the 2nd gear.
Funny thing. I tested it with exact the same Map and same setup on different cars. 50% of them had that problem.
What I realized is, that when the car has to much wheel spin at the launch, it couldn´t shift.
The only thing that helped was to reduce the Boost in 1st gear.
Got the Problem @ 400Bhp and 520NM@2900RPM (after midnight for me, don´t want to change the units). Solved it with less Boost from 2500 to 3500. Without wheel spin I didn´t get any problems.
What crossover value did you end up using for 1st gear boost?
- Bryan
Newbie
Joined: Dec 2007
Posts: 12
Likes: 0
From: Germany / Bavaria
145 for 1st gear. That´s stock @ EDM SSTs. Now I get wheel spin @6000, but that seems to be no problem for the trans.
On a test car I had it also from 2nd to 3rd. Changed the crossover to 115 and that was all.
If I could make the Maps like I do on our rallye cars the SST would never shift I think
On a test car I had it also from 2nd to 3rd. Changed the crossover to 115 and that was all.
If I could make the Maps like I do on our rallye cars the SST would never shift I think
145 for 1st gear. That´s stock @ EDM SSTs. Now I get wheel spin @6000, but that seems to be no problem for the trans.
On a test car I had it also from 2nd to 3rd. Changed the crossover to 115 and that was all.
If I could make the Maps like I do on our rallye cars the SST would never shift I think
On a test car I had it also from 2nd to 3rd. Changed the crossover to 115 and that was all.
If I could make the Maps like I do on our rallye cars the SST would never shift I think
Going by this:
Evo X MR
* 1st gear = 194.3
* 2nd gear = 125.9
* 3rd gear = 93.2
* 4th gear = 70.3
* 5th gear = 53.6
* 6th gear = 41.2
It seems 160 would be a better split between 1st and 2nd?
It's funny because my RA rom has 161 as the stock value.
I'm going to try this out, thanks Schneider.
I still want to ultimately figure out why it's doing this and see if we can change it. If it's indeed from wheel spin I'm now wondering if it's a possible input shaft / engine RPM mismatch issue.
These SST's are complicated buggers...
- Bryan
Last edited by GST Motorsports; Nov 12, 2010 at 03:53 PM.
i have this happen to me to when i am at the track i have never been able to figure it out either it does not happen all the time tho only once and awhile. like you said its really hard to explain whats going on. a have the evox setup on my car i think i got about 320whp. it usually happens when i launch hard. but you gotta launch hard to run 12.2's 
i have this happen to me to when i am at the track i have never been able to figure it out either it does not happen all the time tho only once and awhile. like you said its really hard to explain whats going on. a have the evox setup on my car i think i got about 320whp. it usually happens when i launch hard. but you gotta launch hard to run 12.2's
Ok good (and bad) to hear it's happening to others as well.
I bought a SST equipped Mitsu to help figure all these things out and I've been busy ever since. hahah
- Bryan
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yeah I should get one too :P hehe
I think that 1->2nd mis shift is a different thing, purely the trans cant shift quick enough and the revs are changing so fast that by the time it decides to shift you have hit redline... My guess is more clamping force would fix that....
With your problem Bryan I still think the SST is attempting to shift... And for some reason its locking itself out... As you could see by the clutch slip speeds something really funny is going on.
If your map cleaning doesn't work I will see what other titbits I can pull from the SST in the MUTIII - I have access to Clutch Shift Pressure Solenoid 1 and 2, Line pressure solenoid and Clutch Cooling Solenoid - but I am not sure what they are for...
I have Shift fork positions 1/2/3/4 as well... that might be useful - I don't really know the mechanicals of the SST to say what is useful vs not...
I think that 1->2nd mis shift is a different thing, purely the trans cant shift quick enough and the revs are changing so fast that by the time it decides to shift you have hit redline... My guess is more clamping force would fix that....
With your problem Bryan I still think the SST is attempting to shift... And for some reason its locking itself out... As you could see by the clutch slip speeds something really funny is going on.
If your map cleaning doesn't work I will see what other titbits I can pull from the SST in the MUTIII - I have access to Clutch Shift Pressure Solenoid 1 and 2, Line pressure solenoid and Clutch Cooling Solenoid - but I am not sure what they are for...
I have Shift fork positions 1/2/3/4 as well... that might be useful - I don't really know the mechanicals of the SST to say what is useful vs not...
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Joined: Nov 2009
Posts: 14
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From: California
Consequences?
When it "seems like the car is getting stuck in between 1st and 2nd gear in a weird no-mans land," is any damage actually being done to the engine?
My car has done this a couple of times and I am worried that I am damaging the engine. Is the engine (pistons) suffering from a temporary shortage of oil?
Thank you for any input.
My car has done this a couple of times and I am worried that I am damaging the engine. Is the engine (pistons) suffering from a temporary shortage of oil?
Thank you for any input.
hey razorlab when you noticed this happening do you remember how much fuel you had in the car? this has happened to me a few times and to my knowledge the only times this has ever happened is when i only have 1/4 or less fuel in my tank. just a thought maybe its starving itself.
hey razorlab when you noticed this happening do you remember how much fuel you had in the car? this has happened to me a few times and to my knowledge the only times this has ever happened is when i only have 1/4 or less fuel in my tank. just a thought maybe its starving itself.
you have too much torque going to 1st and 2nd ..
run lower boost ..
my current setup has separate boost maps for all the gears just to combat this ..
you lose approx 2s when it mis shifts ..
run lower boost ..
my current setup has separate boost maps for all the gears just to combat this ..
you lose approx 2s when it mis shifts ..