Need some help on why car is falling on its face, dyno included.
11-21-2014, 09:30 AM
#26
TECH Enthusiast
The PT7675 has made more power than that on smaller cube engines, so I will say back pressure too. What turbo kit is on the car? Any room for a bigger PTE or Borg unit?
11-21-2014, 09:40 AM
#28
No **** sherlock but he's run a small turbined S400 on his 6.0 and a few larger turbos, its close enough that he knows how it will react on this 383. stock48 has had all kinds of setups in the past on his 6.0s, more than any of us responding Im sure.
11-21-2014, 05:46 PM
#30
i have the same kit as you, and will going most likely 380-390 cubic inch and running a pt8847, thats my current plan..i would nevvver run that small of a turbo, thats not even a considered option..i wouldnt run that turbo unless i had a 5.3 and at the max a 5.7...in my opinion you have reached the point where it just canttt flow anymore than your givin it..you defffinately need a bigger turbo for a higher hp #....btw how much lag is there on your setup? i would imagine almost none?
11-21-2014, 05:53 PM
#31
I saw something similar to this not too long ago
Ended up being too long of a pushrod holding the valves open
Didn't exactly fall on its face but it made the same amount of power at 5600 as it did at 6600.
Changed turbos and it still peaked the same, changed cam and it didn't make a difference, swapped lifters and pushrods and it fixed it.
Probably a slim chance that's your problem but it's easy enough to check
Ended up being too long of a pushrod holding the valves open
Didn't exactly fall on its face but it made the same amount of power at 5600 as it did at 6600.
Changed turbos and it still peaked the same, changed cam and it didn't make a difference, swapped lifters and pushrods and it fixed it.
Probably a slim chance that's your problem but it's easy enough to check
11-21-2014, 05:55 PM
#32
i have the same kit as you, and will going most likely 380-390 cubic inch and running a pt8847, thats my current plan..i would nevvver run that small of a turbo, thats not even a considered option..i wouldnt run that turbo unless i had a 5.3 and at the max a 5.7...in my opinion you have reached the point where it just canttt flow anymore than your givin it..you defffinately need a bigger turbo for a higher hp #....btw how much lag is there on your setup? i would imagine almost none?
11-21-2014, 09:12 PM
#33
8 Second Club
11-21-2014, 11:02 PM
#34
Hmm I must be different, didn't peak as early as others.
Stock ls1 with a tc7875 12 psi 16*, 238/242 .605 112lsa. Th400 and also 3 inch dp
Peaked at 6k then falls hard haha. Only ran it out to 7k to make sure the afr was right. Gotta run the car out the back door at 7k cause im out of gear.
Stock ls1 with a tc7875 12 psi 16*, 238/242 .605 112lsa. Th400 and also 3 inch dp
Peaked at 6k then falls hard haha. Only ran it out to 7k to make sure the afr was right. Gotta run the car out the back door at 7k cause im out of gear.
