Acceleration issue over 70mph
Thread Starter
Staging Lane
Joined: Dec 2019
Posts: 54
Likes: 5
Acceleration issue over 70mph Hi hopefully someone can give me a little insight on what might be going on here.. The jist of it is I've got a 64 Nova with an LS1 paired to a tr6060. Engine was used but low miles, then taken down to the block and rotating assembly then rebuilt from there. BTR stage 3 cam, head work, 92mm intake man, ls2 TB, bigger injectors, ect ect. I paired it to a TR6060 and did a stand alone harness for the whole system. Sent ecu out for a base tune with build specs and its runs great...under 75mph. But as soon as i get to 70-75 mph it just stops accelerating and planes out. Regardless of the gear or rpm it just doesn't want to go any faster. Could there be some type of communication issue between the ECU and trans or does it need to be dyno'd?? This is my first build so forgive me if I'm missing something basic, I've missed plenty over the past 3 years.
On a side note I also noticed that when i try and push it past that it somewhat wants to go faster but its definitely does not keep up with pedal position. Entire build has less than 600 miles on it, been a build and drive in progess. My best guess is there is something in the ecu keeping it from allowing it to go faster, but i haven't seen anything online regarding this same issue. I plan to have it on the dyno asap but if it wont even accelerate past 75mph i don't wanna waste the time and money before the issue is resolved if I can.
Any insight would be appreceiated.
On a side note I also noticed that when i try and push it past that it somewhat wants to go faster but its definitely does not keep up with pedal position. Entire build has less than 600 miles on it, been a build and drive in progess. My best guess is there is something in the ecu keeping it from allowing it to go faster, but i haven't seen anything online regarding this same issue. I plan to have it on the dyno asap but if it wont even accelerate past 75mph i don't wanna waste the time and money before the issue is resolved if I can.
Any insight would be appreceiated.
If you have a base tune, you either need to datalog it and have revisions made or take it and have it dyno tuned.
A lot of tuners, including myself, will either pull a bunch of timing or set limiters on base tunes. Because people have a tendency to go out and go WOT even when they are told not to, then blame the tuner.
Have you checked for DTC's or anything?
A lot of tuners, including myself, will either pull a bunch of timing or set limiters on base tunes. Because people have a tendency to go out and go WOT even when they are told not to, then blame the tuner.
Have you checked for DTC's or anything?
Thread Starter
Staging Lane
Joined: Dec 2019
Posts: 54
Likes: 5
So i sent the ecu out to a guy in Texas to have it setup to "run" but he also said it would need to be dyno'd to fully get the whole finished outcome. And I totally plan to do that. I'm just unsure as to why it would limit me at that speed. At the same time it seems like some sort of fail safe or limp mode to protect the motor. It definitely runs rich, so I'm not mad. He never told me to not go WOT but he did say it would need a dyno tune to get everything sorted out of it hp/tq wise. What you said is almost verbatim as far as datalog ect, so would you suggest I just take it to the dyno tuner in its current state and they would know how to work through that with hp tuner? I tried checking DTC last night but couldn't get the OBD software to work...its a dumb bluetooth setup i got from local auto parts store awhile ago.
Thread Starter
Staging Lane
Joined: Dec 2019
Posts: 54
Likes: 5
I Gotcha so most likely the guy who setup my base tune put a limiter on it as well. That make sense. Thanks for the help!
Thread Starter
Staging Lane
Joined: Dec 2019
Posts: 54
Likes: 5
I have not, I was looking through my emails trying to find his contact but I figured I could reach out to the community in case it was just an easy answer. I will find his contact and hit him up as well. The tune was done over a year and a half ago
