Tranny shifting too hard with Hennesey tune

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Rwood_devil

New Member
Joined
Nov 8, 2014
Messages
4
Reaction score
0
Location
West Virginia
I have 2011 with a 445 max boost kit. Took a bit but I finally have the tune sorted out. Had to put 2012 plugs in my 2011 to handle the extra HP. My issue is the tranny. When getting after it in a downshift situation the shift is violently hard to the point I think something in the driveline might break. Of course this is taking some of the fun away from the driving experience. Any suggestions?

BTW- are any of you running a pre filter on your K&N? I believe this might be just what I need to eliminate the small amount of intake noise I still have. Thoughts please.

Thanks folks and Happy Holidays!
 

93markVIII

SHO Member
Joined
Jan 5, 2011
Messages
237
Reaction score
124
Location
MO
lol at hennessey.

does it do the same on the stock tune?
you will need to contact Hennessey and discuss your issue with them, it may be an issue they are aware of, or need to be made aware of.
 

SHOdded

SHO Member
Joined
Dec 25, 2011
Messages
9,045
Reaction score
4,390
Location
Maryland
The tune is usually the reason for hard shifting on these cars, better torque management is required. Does your SHO have the PP package, are you turning Traction Control off, ...?

The trans fluid level COULD be low, as well as the PTU/RDU fluid levels. Wouldn't hurt to make sure these look good.

Which plugs did you install exactly? Did you check the spark plug gap when you installed them? Most folks with a tune are running at 0.028-0.030 to prevent spark blowout (untuned is about 0.035).
 

BamSHO

SHO Member
Joined
Apr 9, 2001
Messages
1,239
Reaction score
987
Location
South Williamsport,PA, US
Did you put the SP534 plugs in, tuned cars are running .030 gap. Allow these are learning transmission, will adapt to driving habits, but sounds like there are tuning issues here. Yeah wouldn't hurt to check trans and PTU fluids, or even having the PTU fluid changed out. I never experienced violent shifts here, just real firm up an down shifts. Are you running the K&N Typhoon or panel filters?
 

Livernois Motorsports

SHOForumSponsor
Sponsoring Vendor
Joined
Apr 25, 2013
Messages
1,508
Reaction score
1,333
Location
Dearborn Heights, MI
I have 2011 with a 445 max boost kit. Took a bit but I finally have the tune sorted out. Had to put 2012 plugs in my 2011 to handle the extra HP. My issue is the tranny. When getting after it in a downshift situation the shift is violently hard to the point I think something in the driveline might break. Of course this is taking some of the fun away from the driving experience. Any suggestions?

Thanks folks and Happy Holidays!

That definitely sounds like something in the logic of the tune that needs to be adjusted. If you have any issues or they cannot get it resolved let me know. Maybe we can help you out.
 

SHO307

SHO Member
Joined
Apr 19, 2010
Messages
88
Reaction score
27
Location
CO
Ditch the tune and give LMS a call.... all tuned SHO/MKS are running LMS or Unleashed. I wouldn't want anyone else touching my car.

I'll second that. I don't even have a tune on my car, but I would never EVER let Hennessey touch my ride after that internet meltdown he had a few years back. Too much scandal around that guy and his---hrmmm---"work" for me to feel safe on a Hennessey tune. Maybe it was real, maybe it wasn't, but the stink on him is too big for me to ignore. Livernois actually seems to have a decent rep around the tuning/street community; if I ever decide to go that route they'll be my first call.

Wouldn't want to get "Hennescrewed"....
 

mval

SHO Member
Joined
Nov 17, 2010
Messages
133
Reaction score
87
Location
MISSOURI
as soon as i run the 89 out of my baby & run a couple 93's through her, lms for sure. when the 2 big guys bpd & crash are running lms nothing more needs to be said.
 

93markVIII

SHO Member
Joined
Jan 5, 2011
Messages
237
Reaction score
124
Location
MO
I'll second that. I don't even have a tune on my car, but I would never EVER let Hennessey touch my ride after that internet meltdown he had a few years back. Too much scandal around that guy and his---hrmmm---"work" for me to feel safe on a Hennessey tune. Maybe it was real, maybe it wasn't, but the stink on him is too big for me to ignore. Livernois actually seems to have a decent rep around the tuning/street community; if I ever decide to go that route they'll be my first call.

Wouldn't want to get "Hennescrewed"....

yup. i wouldn't give that dude a penny.
 
Back
Top