[BlackV6RS]

Car is a 2021 LT1 RS with an A10. I was racing this weekend, seemed like the air wasn't great, was doing 12.2-12.3s at 114-115mph. Car usually does 12.1-12.2s, has been 12.00 before. I did a little bigger than normal burnout due to poor track prep and spun some on previous pass. When I made my run, it was like the throttle was being cut in the lower gears, only did a 2.0 60ft (not due to spinning) and then ran 13.3X at 109mph. I had TC turned off all the way. I did two more runs with similar results, (leaves very soft) I did notice the trans temp was pretty warm, 195 degrees. Is this a nanny killing power or did I hurt something?

[Rayvan]

Could be something as simple as the altitude density that night.

Here's a good on-line calculator

https://racingcalcs.com/density-altitude-calculator/

[laynlo15]

So you didn't have any check engine lights come on? Losing a full second would sure be a concern plus 6 to 7 mph. Especially since you were running low 12s the same day. Post your timeslips. Thanks

[FlukeSS]

Originally Posted by BlackV6RS

I had TC turned off all the way.

To clarify this statement:

There are two methods for turning TC off. One way is ESC COMP Mode which is a quick double tap of TC off button. (This does not turn off stabilitrak)

The other way turns ALL of the nannies off by holding down the TC button for 10+ seconds you'll get a message "ESC OFF" as opposed to "ESC Competitive Mode"

[FlukeSS]

Originally Posted by laynlo15

So you didn't have any check engine lights come on? Losing a full second would sure be a concern plus 6 to 7 mph. Especially since you were running low 12s the same day. Post your timeslips. Thanks

Heat soak? Remember LT1's do not have the extra cooling systems like the SS's and 1LE's do if I am not mistaken?

[3.8TransAM]

Originally Posted by FlukeSS

To clarify this statement:

There are two methods for turning TC off. One way is ESC COMP Mode which is a quick double tap of TC off button. (This does not turn off stabilitrak)

The other way turns ALL of the nannies off by holding down the TC button for 10+ seconds you'll get a message "ESC OFF" as opposed to "ESC Competitive Mode"

There is no way to kill the nannies 100%, there are some vestigial parts that continue to function even after you turn them "off".


For him to lose a second and that mph on the same day would have to be massive weather change or he has other issues going on, possibly fueling. Not sure what auto trans will do when it gets hot either. He has an LT1 which has none of the coolers a SS would have. Kind of made it a useless package to me, other than straight line, but u still get heat soak.

[wnta1ss]

Originally Posted by 3.8TransAM

He has an LT1 which has none of the coolers a SS would have.

Not 'none', just less coolers. In actuality the 2 extra side coolant radiators and the differential cooler are what's on an SS coupe that the LT1 coupe lacks. LT1 still has the engine oil cooler and transmission cooler from what we've heard. Same thing was done on the convertible SS, another model that is not track-rated by Chevy.

[laynlo15]

Originally Posted by FlukeSS

Heat soak? Remember LT1's do not have the extra cooling systems like the SS's and 1LE's do if I am not mistaken?

I'm well aware of that since I have an Lt1 and as I made 3 passes in a row the heat soak was obvious since I couldn't open the hood as I was running True Street at the NMCA event. A 10 degree increase in Temps from 76 to 86 and DA went from 2100 to 2900 my car slowed down a tenth and a half but the mph didn't drop as the car starting cooling down track but it killed my 60ft and 1/8 mile. Just too much heat under the hood. His is extreme losing a full second and 6 mph.

[laynlo15]

Originally Posted by wnta1ss

Not 'none', just less coolers. In actuality the 2 extra side coolant radiators and the differential cooler are what's on an SS coupe that the LT1 coupe lacks. LT1 still has the engine oil cooler and transmission cooler from what we've heard. Same thing was done on the convertible SS, another model that is not track-rated by Chevy.

It also doesn't have the Diff Cooler. As far as the other coolers the SS has I wasn't aware of. So news to me and since I has a 1ss also I'm learning something here about the Lt1.

[BlackV6RS]

I ran it with TC off all the way (holding it 10 sec) and also in ESC mode and the car ran similar results. I was wondering if it was heat soak as well, but I have race the car quite a few times and never had this issue. The only other thing that I can think of is that I was low on fuel (under a 1/4 of a tank) but I wouldn't think this would have cause an issue...? The air D/A got better as the night went on but my car went slower. I made like 6 passes that night 12.3 @115, 12.3@114 12.4@114 then 13.2 @109, 13.3@109 and 13.X(I didn't get a slip for the last run) DA was 1700ft, so not that bad.

[95 imp]

Gonna be hard to figure out w/o a data log.

Maybe the long burnout got the tires sticky and you hooked good. Now you have the "bog" issue.

[cjperformance]

Originally Posted by BlackV6RS

I ran it with TC off all the way (holding it 10 sec) and also in ESC mode and the car ran similar results. I was wondering if it was heat soak as well, but I have race the car quite a few times and never had this issue. The only other thing that I can think of is that I was low on fuel (under a 1/4 of a tank) but I wouldn't think this would have cause an issue...? The air D/A got better as the night went on but my car went slower. I made like 6 passes that night 12.3 @115, 12.3@114 12.4@114 then 13.2 @109, 13.3@109 and 13.X(I didn't get a slip for the last run) DA was 1700ft, so not that bad.

Couple of ideas I didn't see others mention...

Given your last few runs were much lower MPH as well as ET... it indicates a loss in power not just traction. Check your air filter, etc... make sure you didn't suck in a plastic bag or something.

You could have also collapsed/clogged the grid in your catalytic converter.

I assume no codes, so prob no misfire... but worth checking plugs and wires too.

Other than that... you'd have to see if it gets back to normal next time or is still low on power. it *Could* be heat soak. It will dial back timing and power if the engine hits certain heat thresholds, but... I think it would have to be pretty significant to dial things back that far.

Could do a leakdown check and compression test too.

[BlackV6RS]

Originally Posted by 95 imp

Gonna be hard to figure out w/o a data log.

Maybe the long burnout got the tires sticky and you hooked good. Now you have the "bog" issue.

When I ran a 12.00 in the car it dead hooked and did a 1,7X 60ft, this was definitely a bog but I don't think it was from hooking.

Also no check engine light or reduced engine performance light.

[BlackV6RS]

Also to note, the car is all stock with 15,000 miles