Re: Bogging/shifting problems

[shoNoff]

I was having bogging/shifting problems every few runs. So any run you see in the 12.8's the car bogged hard at the top of first. Almost like it smashed the limiter and wouldn't let it shift. I did also hit 110mph 5/6 times tonight which made me very happy.

I wonder how big an issue this is. I have had this happen as well.

Can't put my finger on what it is. But it seems the harder I launch the car the more prone to it, it is.

[SHOdded]

So it is bogging down, not creating wheelspin or wheelhop?  Definitely narrowed down to powertrain, or even more specific?

[shoNoff]

If I come out hard say launch around 2400 or so and get any sort of wheel hop the car hits the rev limiter or hesitates to shift. You can see if you watch the video any pass I make in the 12.8's right after the 60 foot you can see the nose dip down. To me it's almost like something in the drivetrain is holding the car back from breaking itself. Sometimes it's not even a limiter hit. Just the nose will dip quickly then the car will shift. Last Friday it happened to me up there and the car was smashing the limiter in first. I thought I broke the transmission. So I eased her down the track to a 17.4 or something.

[SHOdded]

Will have to chew on it but tuned SHOs typically do not like being launched that high.  Thats more stock territory.  Would be thinking more torque converter related if anything.

[TopherSho]

If I come out hard say launch around 2400 or so and get any sort of wheel hop the car hits the rev limiter or hesitates to shift. You can see if you watch the video any pass I make in the 12.8's right after the 60 foot you can see the nose dip down. To me it's almost like something in the drivetrain is holding the car back from breaking itself. Sometimes it's not even a limiter hit. Just the nose will dip quickly then the car will shift. Last Friday it happened to me up there and the car was smashing the limiter in first. I thought I broke the transmission. So I eased her down the track to a 17.4 or something.

you are nearly perfectly describing low tranny fluid.  with my car,  if the tranny oil is not above the checker-marks and almost covering the dip-ball... my tranny FREAKS out stalls,  dropps power then shifts into 3rd or 4th and stalls.

i would check your tranny oil... it is VERY command for many members here to have to add 1/2 a quart more once the power gets above 500fllbs..

[shoNoff]

I will openly admit I'm an old school drag racer. And I'm a firm believer of run it like you stole it. I do not go easy on my cars at the track. I'm learned a lot about the car this year racing it. The more power I started to make the lower I had to go on the launch. It seems now right about 2000rpm is all it likes. That's an interesting thought on the converter though. I wished I datalogged those runs last night but I didn't. Im not doing myself any favors running 35 series tires either. 


Topher I checked all the fluids before I went to the track. I usually always do.

[TopherSho]

I will openly admit I'm an old school drag racer. And I'm a firm believer of run it like you stole it. I do not go easy on my cars at the track. I'm learned a lot about the car this year racing it. The more power I started to make the lower I had to go on the launch. It seems now right about 2000rpm is all it likes. That's an interesting thought on the converter though. I wished I datalogged those runs last night but I didn't. Im not doing myself any favors running 35 series tires either. 


Topher I checked all the fluids before I went to the track. I usually always do.

rgr that,  but have you added above the hash?  Once I went meth/24+ degrees timing i had to add more to stop the trans from dumping at the end of 1st.  If you have carry on!

[802SHO]

I will openly admit I'm an old school drag racer. And I'm a firm believer of run it like you stole it. I do not go easy on my cars at the track. I'm learned a lot about the car this year racing it. The more power I started to make the lower I had to go on the launch. It seems now right about 2000rpm is all it likes. That's an interesting thought on the converter though. I wished I datalogged those runs last night but I didn't. Im not doing myself any favors running 35 series tires either. 


Topher I checked all the fluids before I went to the track. I usually always do.

rgr that,  but have you added above the hash?  Once I went meth/24+ degrees timing i had to add more to stop the trans from dumping at the end of 1st.  If you have carry on!

Very interesting I will add some more fluid I think.  Had very brief issue also.

[shoNoff]

I will openly admit I'm an old school drag racer. And I'm a firm believer of run it like you stole it. I do not go easy on my cars at the track. I'm learned a lot about the car this year racing it. The more power I started to make the lower I had to go on the launch. It seems now right about 2000rpm is all it likes. That's an interesting thought on the converter though. I wished I datalogged those runs last night but I didn't. Im not doing myself any favors running 35 series tires either. 


Topher I checked all the fluids before I went to the track. I usually always do.

rgr that,  but have you added above the hash?  Once I went meth/24+ degrees timing i had to add more to stop the trans from dumping at the end of 1st.  If you have carry on!

No I haven't at all. It's honestly worth a shot. Unfortunately I won't have a chance to test it until April when the track opens. Thanks for the response.

[Macgyver]

If I come out hard say launch around 2400 or so and get any sort of wheel hop the car hits the rev limiter or hesitates to shift. You can see if you watch the video any pass I make in the 12.8's right after the 60 foot you can see the nose dip down. To me it's almost like something in the drivetrain is holding the car back from breaking itself. Sometimes it's not even a limiter hit. Just the nose will dip quickly then the car will shift. Last Friday it happened to me up there and the car was smashing the limiter in first. I thought I broke the transmission. So I eased her down the track to a 17.4 or something.

you are nearly perfectly describing low tranny fluid.  with my car,  if the tranny oil is not above the checker-marks and almost covering the dip-ball... my tranny FREAKS out stalls,  dropps power then shifts into 3rd or 4th and stalls.

i would check your tranny oil... it is VERY command for many members here to have to add 1/2 a quart more once the power gets above 500fllbs..

I am having this issue and I have added the extra Trans Fluid long before I got an Etune from Brad. I think we need to shift sooner from 1st to 2nd then stretch out shifts 2-3 and shifts 3-4 to max RPM capable shift point

[802SHO]

If I come out hard say launch around 2400 or so and get any sort of wheel hop the car hits the rev limiter or hesitates to shift. You can see if you watch the video any pass I make in the 12.8's right after the 60 foot you can see the nose dip down. To me it's almost like something in the drivetrain is holding the car back from breaking itself. Sometimes it's not even a limiter hit. Just the nose will dip quickly then the car will shift. Last Friday it happened to me up there and the car was smashing the limiter in first. I thought I broke the transmission. So I eased her down the track to a 17.4 or something.

you are nearly perfectly describing low tranny fluid.  with my car,  if the tranny oil is not above the checker-marks and almost covering the dip-ball... my tranny FREAKS out stalls,  dropps power then shifts into 3rd or 4th and stalls.

i would check your tranny oil... it is VERY command for many members here to have to add 1/2 a quart more once the power gets above 500fllbs..

I am having this issue and I have added the extra Trans Fluid long before I got an Etune from Brad. I think we need to shift sooner from 1st to 2nd then stretch out shifts 2-3 and shifts 3-4 to max RPM capable shift point

Makes sense.  In my car, I thought it was due to wheel spin.  1st...spinning...catch some traction...top of first...spin again...catch..then into 2nd.  Something like that.  Wish I had this thing on a dyno to see where power is at.  The Continental ExtremeContact DW tires I have are really good...but with the power...and track prep being hit or miss..i think a better tire is needed.  With better traction I think diagnosis will be more accurate if this issue persists. 

[Jordan]

I have the issue of losing traction on the 1-2 shift. Myself and brad have really tried adjusting a few things as far as the shifting goes. It'll lose traction on the 1-2 hit then completely pull itself out of gear because the stability/ traction control completely freaks out. I only have this problem launching on hard prep at the strip or in wet conditions on the street. Launching at 2k on the dry road I will be fine. Launching 2k on a prepped strip gotta watch the traction. Pretty sure it's due to the fact that I am off the heavy prep at the top of 1st.

[Jordan]

Also could have a bit of wheel hop now that I think about it. That coupled with more power with the race fuel tune could definitely cause problems on the 1-2

[ZSHO]

@- shoNoff feel free to start a separate Topic in the Troubleshooting section!   
Something is definitely a miss based on the great video you provided earlier!,
It could also be suspension related especially if your nose is dipping IMO!

I also ran the Continental DW summer tires for a while and served me quite well which also netted me a best 1.752 60' times....
I am eagerly awaiting to try my current Dunlop's extreme sports very soon. Z 

[jims2015]

I have the issue of losing traction on the 1-2 shift. Myself and brad have really tried adjusting a few things as far as the shifting goes. It'll lose traction on the 1-2 hit then completely pull itself out of gear because the stability/ traction control completely freaks out. I only have this problem launching on hard prep at the strip or in wet conditions on the street. Launching at 2k on the dry road I will be fine. Launching 2k on a prepped strip gotta watch the traction. Pretty sure it's due to the fact that I am off the heavy prep at the top of 1st.

I also was losing traction on the 1-2 at the drag strip to the point the car would actually dance sideways and trigger stability control. One time it even shut down for about 10 seconds almost giving me a heart attack. From that point on, I always completely turned off stability control and never had a problem since.