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Discussion Starter #1
Not very familiar with the second cam concept...I have a couple questions for those in the know:

Does the second cam kick in at 6000 rpm in all gears / all speeds?

How would you know if you second cam is not engaging? (I have felt when it does engage).


Does the second cam only engage in the "performance zone" of 6,000 to 8,000 rpm?


Is there a thread that I should be reading? I did a search on "second cam" and not much came up.

Thanks!
 

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Not very familiar with the second cam concept...I have a couple questions for those in the know:

Does the second cam kick in at 6000 rpm in all gears / all speeds?
6200 RPM for all gears and speeds.
How would you know if you second cam is not engaging? (I have felt when it does engage).
You can hear the engine noise change to a higher pitch. If the car is not warmed up or is experiencing fuel starvation you may hit a rev limiter at 6000 rpm. You'll KNOW when that happens.

Does the second cam only engage in the "performance zone" of 6,000 to 8,000 rpm?
it will be engaged from 6200 RPM to redline at 8500 RPM (so basically, yes). If you up shift while redlining, it could stay on the second cam in the next gear. If you want the cam to kick in at a lower RPM you will need to replace or flash the ECU...
 

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Discussion Starter #3
6200 RPM for all gears and speeds.

You can hear the engine noise change to a higher pitch. If the car is not warmed up or is experiencing fuel starvation you may hit a rev limiter at 6000 rpm. You'll KNOW when that happens.



it will be engaged from 6200 RPM to redline at 8500 RPM (so basically, yes). If you up shift while redlining, it could stay on the second cam in the next gear. If you want the cam to kick in at a lower RPM you will need to replace or flash the ECU...
Should I always feel that "jolt" in all gears / all speeds?

So in this scenario, if I hit 6200 rpm in 5th gear it automatically kicks in, correct? If it doesn't, that means there is some sort of mechanical failure?

I was...ummmm..."driving with" a corvette the other day on a long open stretch of highway...5th gear...last I looked I was somewhere near 6000 rpm, but I didn't take the time to actually look down...and was waiting for the second cam, but decided not to push too hard...the cam never kicked in...but now I think it's cause I didn't have the stones...and didn't trust the other driver.

Disclaimer: I don't drive like that "normally", but when you have the chance to take on an a-hole vette driver driving like an a-hole and it's an open straight...I mean come on!
 

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Should I always feel that "jolt" in all gears / all speeds?

So in this scenario, if I hit 6200 rpm in 5th gear it automatically kicks in, correct? If it doesn't, that means there is some sort of mechanical failure?
You won't necessarily feel a "jolt" when it kicks in, the higher gears seem to have less of a kick in my car. However, you should be able to hear it in the engine. I seriously doubt it's not kicking in. If that really is the case, you'd have to talk to a mechanic about it (or maybe charliex would have some insight, he is the ECU expert around here).
I was...ummmm..."driving with" a corvette the other day on a long open stretch of highway...5th gear...last I looked I was somewhere near 6000 rpm, but I didn't take the time to actually look down...and was waiting for the second cam, but decided not to push too hard...the cam never kicked in...but now I think it's cause I didn't have the stones...and didn't trust the other driver.
Before the 2nd cam kicks in 5th, you're probably going well over 100 mph (maybe even 120 mph), so I would understand if you slowed down before it happened.
 

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Youll need a 3rd and 4th cam to keep up with a corvette at those speeds!
 

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If your car is unable to switch to the second intake camshaft lobes it will not permit you to go above 6200rpm.

It will behave as a rev limiter at that point.
 

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Discussion Starter #7
You won't necessarily feel a "jolt" when it kicks in, the higher gears seem to have less of a kick in my car. However, you should be able to hear it in the engine. I seriously doubt it's not kicking in. If that really is the case, you'd have to talk to a mechanic about it (or maybe charliex would have some insight, he is the ECU expert around here).


Before the 2nd cam kicks in 5th, you're probably going well over 100 mph (maybe even 120 mph), so I would understand if you slowed down before it happened.
Yeah, I think I touched 105 and then said out loud "this is getting stupid"...fun, but stupid...so clearly I was not near 6200 rpm...I tried to figure it out driving last night...I was in 5th at approx 80-85 mph and I think between 4000 and 4500 rpm...looks to be about an additional 10 mph to each 1000 rpm in that range? Does that sound about right?

I think my "favorite" gear is 4th - good cruising gear, great acceleration potential.

On my nightly pleasure cruise last night I found the "kick" in 2nd - so there's nothing wrong - but realized there is less of a "jolt" in the higher gears...4th to be exact...still getting use to the car...I guess I was expecting the "jolt" in all gears like a turbo or something. It makes sense now.


Thanks for the help!
 

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Discussion Starter #8
Youll need a 3rd and 4th cam to keep up with a corvette at those speeds!
True...

I kept thinking about that Youtube video of "Elise vs. Corvette" while we were driving and saying to myself - man I wish there were some curves coming up!

YouTube - Lotus Elise (190 HP) versus Corvette Z-06 (505 HP)

In my opinion, I would take the lack of flat-out straight away speed versus the finesse and nimbleness of the Elise all day long...anyone can drive straight...especially a-hole corvette drivers...no offense if there are any a-hole vette drivers here...
 

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Yeah, I think I touched 105 and then said out loud "this is getting stupid"...fun, but stupid...so clearly I was not near 6200 rpm...I tried to figure it out driving last night...I was in 5th at approx 80-85 mph and I think between 4000 and 4500 rpm...looks to be about an additional 10 mph to each 1000 rpm in that range? Does that sound about right?

I think my "favorite" gear is 4th - good cruising gear, great acceleration potential.

On my nightly pleasure cruise last night I found the "kick" in 2nd - so there's nothing wrong - but realized there is less of a "jolt" in the higher gears...4th to be exact...still getting use to the car...I guess I was expecting the "jolt" in all gears like a turbo or something. It makes sense now.


Thanks for the help!
This should help
 

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Discussion Starter #10

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6200 RPM for all gears and speeds.
The only exception would be if you have a different ECU fitted. e.g. the Lotus sport ECU brings in the 2nd cam at around 5800 rpm.

.....much fun :D
 

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Awesome!

Thanks!
Also, keep in mind with this chart that it was someone else's car on a dyno and your speedo is in no way accurate. Redlining 3rd my car usually shows 100 mph on the speedo, but I am really going a little over 90 (you can verify how off your speedometer is with a GPS...sort of). Just assume your car is going 5-10 mph slower than it reads. So with the exact car/conditions as the chart, your speedo would probably show 110 or 111 when hitting the cam in 5th.
 
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