No, you have no idea if you think you'll go from 150 to 160 mph with only 20 more hp. It's physics, man. Power is related to speed by the cube of the speed difference. To go from 160 to 150 looks like this: (160/150)^3 = 1.214. So, you need 1.214x the power you currently have, in other words, you need 21.4% more hp. Assuming your 230 hp estimate (my 255 was just a ballpark), 21.4% = 49 more hp to hit 160 mph. So, ~280 crank hp assuming all else equal. Downhill and with a tail wind doesn't count.

Here's another example:

ZL1 top speed (official 2 way averaged runs) = 198 mph. Assume your car has a top speed of 150 mph based on your posts:

(198/150)^3 = 2.3
Your car makes 275 hp stock (comparing stock for stock) and a ZL1 is 650 hp. 275*2.3 = 633 hp. That's pretty close to 650 hp. The difference can be explained by several potential things: Accuracy of your 150 mph reading, assumed hp at that speed, the fact that the ZL1 has more rolling resistance with the wider tires, and probably slightly more drag due to the additional cooling and downforce.

You think you can get 21% closer to a ZL1's top speed with only 5% of the power deficit improvement (20 hp)? Good luck.

I was just looking for info on a 4 cylinder Camaro, a fairly simple question I thought. The only info asked for I didn't get :)
I will race my car again in October, I predict I will enjoy it! If I can find another 15-20HP I believe I will achieve my goal. Hopefully you will also do something you enjoy:)


Kurt

Thanks for the wishes for good luck, 'm sure I'll need it!
I attached a screen shot from my GoPro when I went past the speed trap on the morning run down, it was about 30 miles in just before you enter the canyons. My speedometer was just over 150, you can see the trap has me at just over 154mph. On the return run in the afternoon the added heat cost me a couple HP, so 151 was my top speed on the return.


Kurt

Final mounted my catch can for trapping vapors before they get in my inlet tube today. Couldn't get the bracket and can powder coated as my guy was just backed up weeks, so they got the Krylon treatment! One step closer!


Kurt

My race is over and I made my license move forward! Because of Covid I could not get my intercooler (still on backorder!) so I only took off the cat and removed the silencer between the turbo-air box. I did also add a trans cooler that let me stay in 6th gear and a small front spoiler. I averaged 149.5 over the 59 miles on my GPS with a top speed of 168.1! I was surprised how well it pulled 6th gear this year, much better. I had better temperatures that I'm sure helped as it was 16 degrees cooler today than my April run. My timing is reducing now at full power, so I suspect I'm getting all the 275 horses!



Kurt

The LTG 2.0 is not designed for high speed runs. They can be detrimental. I typically suggest keeping the 2.0 below 145 MPH... There is an inherent flaw in the PCM logic that leans out the LTG above these speeds... Even with tuning, its almost impossible to correct this flaw, as it is embedded in the hard coding...

That is why the ATS manual recommends both an additional liter(quart) of oil, as well as running 99 octane or better fuel.

I believe the "flaw" you speak of is a design parameter that requires race fuel for race situations. It also makes the most of the platform for those situations as well.

Would be interesting to see someone do a set of high speed runs and compare high octane fuel compared to 93 octane.

If "427" had his runs with high octane, then he would be within parameters if he followed the manuals requirement of adding an additional liter of oil as well.

Also to 427, so your whole gain was running in cooler temps and the fact you pulled the cat off.

Pulling the cat off is something of a "cheat" in gaining, but so be it. That was probably the primary reason it pulled in 6th beyond the cooler temps. Honestly, I doubt anyone else would notice what you have, given the fact of doing high-speed constant runs. Most people spend very little time at those speeds.

As you, yourself stated, you are getting the full output of what it is programmed for.

The full output of what it was programed for is exactly what I wanted. I basically held it wide open for 20 minutes, twice. The fuel wasVP MS109 unleaded, it's way more than whats needed here, I use it commonly at work if the engines (V8) are below 1500hp flywheel. The added airflow is what I needed so I could run the required speed.



Kurt

All GM car engines pass 100 hour durability at rated HP +10% running between peak TQ-HP, the engine doesn't really understand MPH. I ran my oil .5 overfull and added a trans cooler so I could run 6th gear. My trans was 244f and my oil was around 230F at the end of the run, both of those I'm really happy with.


Kurt

Kickass, that is real useful "realworld" data we can all use.

Nice to see that you proved out the "race gas" aspect that is part of the owners manual.

So, what that REALLY means is that the engine is designed to run hard under racegas and is marginal when run hard under pump gas.

Again, this comes down to "engineered parameters". ie, it is "on the edge" all the time and expects to compensate just ahead of "bad circumstances". Which, if you spec race gas is somewhat OK in regards to having margin. But, that is not unlike shooting for a 91 octane fuel requirement and then getting "bad gas" (or the stations tank was filled with the wrong octane) and the octane dropping to 87 and you needing the computer to "figure it out" and not blow anything up.

In other words, it is all a compromise. Again, it just illustrates how the factory really needed to put in forged rods and pistons from the start.

Again, good to know that the engineering really works "in the real world". But, I also have to wonder if you "just got a good one" compared to many horror stories of people popping their engines driving "normal".

I would bet that the closed-loop status of the system has some serious "holes" in it. What I mean by that is that a combination of "bad sensor data" that happens more often than expected can (and does) cause a "perfect storm" and the system applies more timing that it should.

Either that, or there are a lot of "bad batches" of either pistons or poorly gapped top rings that cause problems. Oh, and I am sure there are plenty of "bad tunes" out there as well that end up causing issues.

BTW, which intercooler have you been waiting for?

I agree with the beast. Its all been proven in any vehicle that adding more bolt ons and fine tuning thr air fuel ratio results in more power as long as you have equal air going in and out. Why engines are nothing more than an air pump.
Been doing imports in thr late 90s and then fast and furious came out, causing people to believe that bolt ons result in more power lol. We had before ecu software today's world, that we had to piggyback or buy an ecm (motec,aem, apexi,greddy, jwt) then use their software to do basically what your local tuner does today.
My old mazdaspeed protege had a lot more $$$$ dumped into it to get the same results to get what this camaro can do. Just a point.
These ecus today are quite picky. I have mine canned tuned basically and its more of a calibration more than anything. I still get random codes coming in and have to record them so I can refresh it and disable the codes. Quite irritating, but I get it.

Actually "A" GM test car passes 100 hour durability test before the Milford team releases it for production. This is definitely not "ALL".. As far as the car "not understanding MPH", Ok, lol... I was just trying to help you out from experience. Octane is not going to change anything.

The engine test is run on one engine, not a car, and it's not run in Milford. Milford is more about testing the whole car, many times engines in development will be at Milford running in the test cars, but many don't make release.
Octane raises resistance to knock, it's more of a safety feature for the engine. I use it when I race like an insurance. I also like the consistency of VP fuel.



Kurt