Turbo Dynamics 3” Exhaust Tunes

[@123]

Peak RPM should be 8800-9000 not 8300. Too much load on the

Peak RPM should be 8800-9000 not 8300. Too much load on the motor

no i mean if it knock its gonna drop rpm right?

 

[eightpilot]

On the 1100 sleds we sent different tunes for Wisconsin. Not on the 998... We don't have any issues with knock... We have a huge amount of tunes out there with no issues. This is the worst case I've seen.

I'm sure the fuel in that sled is absolute garbage OR his knock sensor is overly sensitive... Even at 16.5 psi he claims to see knock no way...

We have run 87 octane on max 20 for 500 feet before seeing knock and run max 20 on 94 octane.

Fuel may be an issue.... But fresh pump 93 with 10% ethanol is the best i can do.... I have 2 guys with the same tunes running this WI pump gas without knock. I have a feeling that its false knock to tell you the truth. But I purchased the data log and a wideband to narrow down the possibilities.... Will have the sled out on Wednesday for testing... I have no doubt that Ben and I will figure this out when he gets the uploads...

 

[See n blue]

Fuel may be an issue.... But fresh pump 93 with 10% ethanol is the best i can do.... I have 2 guys with the same tunes running this WI pump gas without knock. I have a feeling that its false knock to tell you the truth. But I purchased the data log and a wideband to narrow down the possibilities.... Will have the sled out on Wednesday for testing... I have no doubt that Ben and I will figure this out when he gets the uploads...

If it runs on 91 then how bad can the 93 be?

 

[Turbo Dynamics]

so if i understands correctly if my rpm is low like 8300 at start i don’t continue?

Short momentary drops to 8300 is ok... But under full load it should recover and maintain 8800 to 9000 ideally 9000

 

[**sj**]

spin it up to become less knock sensitive...

 

[eightpilot]

Well it’s at 11.8 AFR on ECO and knocking to beat hell with fresh 93 octane. Sent the files to Ben. I think it’s false knock from the clutches. You can see the knock pings go up as the mph increases. These graphs are on ECO.

 

[**sj**]

Stupid question... Are you running 2 bar tuned with a 3 bar sensor????

 

[eightpilot]

Nope. Running a Gap 3 bar from TD

 

[ROCKERDAN]

Nope. Running a Gap 3 bar from TD

Thats what SJ asked....are you running a 2 bar tune with 3 bar sensor? Not sure that would cause false knock though.

Dan

 

[eightpilot]

No... My tunes say 3 bar...

 

[eightpilot]

All tunes end in A23 and 3 stands for 3 bar from what I've been told...

 

[Beerman]

Well it’s at 11.8 AFR on ECO and knocking to beat hell with fresh 93 octane. Sent the files to Ben. I think it’s false knock from the clutches. You can see the knock pings go up as the mph increases. These graphs are on ECO.

This makes no sense, has to be false knock from something. I know how frustrating this must feel when you're the only one experiencing it.

 

[sledding rocks]

im not sure on how many miles on your sled , I would check your primary clutch for excessive wear , which could cause noise levels that would set off your knock sensor , process of elimination , check for loose bolts or motor mounts ,

 

[Turbo Dynamics]

Well it’s at 11.8 AFR on ECO and knocking to beat hell with fresh 93 octane. Sent the files to Ben. I think it’s false knock from the clutches. You can see the knock pings go up as the mph increases. These graphs are on ECO.

Wow... I have never seen this. Definitely a one in 2000 case.

The knock sensor is clearly registering knock.

I have seen it 3 times since we did the 1100 turbo in many years. Bad knock sensor. A sled we seen would knock even stock with 91 octane fuel. Guy replaced his knock sensor. Problem gone.

Another possibility... The knock sensor could have been overtorqued. Which makes them very sensitive to a point normal engine noise can trigger it. As you rev up and power goes up natural noise levels rise even when zero knock is present.

Other option drivetrain clatter. Excessive clutch noise sending knock signal into the block. I have never seen a clutch that noisy so very unlikely...

Last option and the most dreadful. Rod knock.
I have never had this issue on a sled motor ever. But I have had a race car start rod knocking that was not audible due to oil starvation during cornering and that triggered crazy knock readings. Again super unlikely.


Throw c16 in it 2 gallons of it... That will rule out any engine noise or oversensitive knock sensor if it stops knocking pointing towards a fuel issue.

I feel like we should reflash this sled just in case

 

[eightpilot]

Going through the primary tonight..... Will mix in 2 gallons of c16 as well...