[terrydennis]

I'm a bit uneducated. I currently own a 2011 CTS-V. I am wondering what it would take to make a V3 (2016 etc) CTS-V
perform as well or better than a CT5 Blackwing. I would rather spend less money on a used CTS-V and mod it a bit than buy a Blackwing out right. I'm also considering California compliance, but it's not that critical. So what would do it? A pulley and a tune?

 

[Heavymetals]

Nitrous.

 

[Ctarb1]

It’s the Same engine right so shouldn’t be to hard

 

[pfram]

I think it will be pretty easy. Just 1 bolt on of choice may do it, certainly 2 should. Cai, pulley, tune, long tubes, flex fuel etc.

I went very mild with rotofab, 2.3 upper only, flex fuel sensor and tune, and am at 620 something. 596 without the flex fuel. Don't know what baseline was. Would imagine the blackwing would show around 550-570 maybe? No idea, I'm sure the numbers are out there somewhere.

 

[Rubber Duck]

Engines having DD / PD Blowers make it easy, because you can open up the LSA / LCA, add duration & make more HP. But you will not be increasing what is called the Overlap Triangle. This is because by widening the centerlines, or the distance (given in degrees) between the Intake and Exhaust lobes (see below), you will be opening up the distance between them, and thereby decrease the overlap, which in turn is what makes engines with high duration camshafts, fail the smog test.

-decrease the distance between the intake and exhaust lobes but
adding duration is required to meet CA Smog and make more hp-

A small pulley change can then help. If we remember that boost is simply a restriction to air flow, a small pulley change can now also help. If you want to, you can add an CAI, but at your desired HP, you don't need it to get to your desired HP.

Now, you have most likely reached your goal on the inlet side of the engine. But what about the outlet side? Where you headed for HP, really does not require a full set of headers (non are approved for CA to my knowledge) simply put test pipes on, or change to a better muffler.

For these engines I always recommend at least 'Flex Fuel'. This is because Ethanol's (E85) being an oxygen based fuel, has a high latent heat of vaporization, which is excellent. This greatly aids in generating hp, and should amount to at least 50rwHP in your case.

Here is a more complete graph, which some will get a headache from..lol but will help others.

Cheers

 

[Lt1z]

…

 

[papi]

I was told that anything other than a stock tune will not pass california smog anymore. Any engine mods that do not change the stock tune have to be carb approved also.

Only good thing is if you buy new, first smog won’t be till 8 years later. Unless it’s a diesel truck, then you have to go every 2 years from new.

 

[Rubber Duck]

Im not sure why you would say that? Any and all camshafts are for competition use. Overlap is meaningless with how tests are run. Please edit so people don’t find inaccurate information.

They can fail you because of the idle of the car. . . .
Both / Either for Chop, or high Engine Idle Speed!

Does not the overlap of the cam, play a large part in the tune required?

Don't high overlap camshafts not pull sufficient vacuum at lower engine idle RPM,
requiring the engine idle speed to be decreased 'Anymore'?. . .

To me; Engine Tuning, is directly linked to Camshaft Tuning!
And tuning for high overlap camshafts, is highly linked to what camshaft 'Should Be Used'.

---------------------------------------------------------

I worked with one person, some years back.

The local smog guy failed his car, because of a slightly high & still somewhat rough idle.
***He had tuned the car that way on purpose, not desiring to have to a really high idle on smog day.

Changed the cam, made about the same power on the dyno.
And oh yes, used another tuner. . . Then his car passed!

---------------------------------------------------------

You wrote:
"Any and all camshafts are for competition use"
And if anyone coming up on this forum is looking for serious power, the camshaft is usually one of the first things they replace! So to me; this is a 'Mute Point' and is serving you as some sort of 'Rhetoric'. . . .

Matt,
I suggested to the OP he use you, no problem I would think!

Sorry my friend; possibly I should have considered more, as I think I wrote to much.
For that I apologize. . .

But I do still stand by my technical points!

 

[Rubber Duck]

I was told that anything other than a stock tune will not pass california smog anymore. Any engine mods that do not change the stock tune have to be carb approved also.

Only good thing is if you buy new, first smog won’t be till 8 years later. Unless it’s a diesel truck, then you have to go every 2 years from new.

And I believe I covered this in my reply to Matt.

Cheers

 

[Lt1z]

…

 

[Rubber Duck]

You seem to be missing the point. Im just asking that you edit the mis information out of your post. We offer nothing for an LT4 that would be compliant.

Very good, I did not know this Matt.
Problem solved!

As you know; I always suggest people seeking this type of help should contact you.

Again, I apologize Matt.

-------------------------------------------

However, you originally wrote:
"Overlap is meaningless with how tests are run. Please edit so people don’t find inaccurate information."

Perhaps you simply got mixed up?
But that pretty much is why I responded to your earlier post in the manner I did.

Take care,
Bruce

 

[Lt1z]

Very good, I did not know this Matt.
Problem solved!

As you know; I always suggest people seeking this type of help should contact you.

Again, I apologize Matt.

-------------------------------------------

However, you originally wrote:
"Overlap is meaningless with how tests are run. Please edit so people don’t find inaccurate information."

Perhaps you simply got mixed up?
But that pretty much is why I responded to your earlier post in the manner I did.

Take care,
Bruce

No I didn’t get mixed up. Simply wanted you to
Edit your post saying we offered something that we do not.

 

[Rubber Duck]

Below is a few simple cut and pastes I just made from a topic on Speed-Talk
Re: Why does overlap make a rough idle?

As I only responded above with a simple vacuum versus engine idle speed, I thought I would cut and paste this post, as it goes into the reasons much more deeply. While not deep enough for some, I believe it will serve well here.

Again, I am doing this simply for those that might not understand why overlap is critical to (but might desire to understand why) not only making HP in IC Engines, but also to how an engines tune might also have to be modified.

The blow-down issue which Bill relates to, is highly critical with these engines. Header Pipe Size, as well as fuel one is going to run, is critical with these engines, and relates right back to the Exhaust Valve Opening (IVC).

***This is why some of the smog guy's turn you away, if your idle speed has been consciously modified from stock

Post by engineguyBill » Fri Mar 23, 2012 11:28 am

Virtually all four cycle engines, even in stock form, have some valve overlap. Rough idle is the result of increased duration, which results in much longer overlap period. Intake valve is opened earlier and exhaust valve is closed later in the cycle, which results in exhaust gas diluting the intake mixture at low engine speeds. At higher engine speeds the engine smooths out as the exhaust gasses flow out much quicker, the result of some exhaust "blow down" when the exhaust valve opens while there is still some combustion pressure in the cylinder. The quickly exiting exhaust gas also results in a slight negative pressure which may even pull intake mixture into the exhaust system at very high RPM. Overlap can be the engine's friend, as well as an enemy.

Post by PackardV8 » Fri Mar 23, 2012 11:46 am
To expand upon this, "At high RPM overlap can be horsepower's friend, but overlap is always an enemy of a smooth, efficient idle."

Rick360 » Fri Mar 23, 2012 1:18 pm
At idle the intake manifold vacuum is high so it will draw from the cylinder anything it can when the intake valve is opening.

 

[Rubber Duck]

No I didn’t get mixed up. Simply wanted you to
Edit your post saying we offered something that we do not.

Matt,
Why are you 'Forcing this issue'?

Your now going back and deliberately editing your earlier posts?
Some now show no content. . . .

But you could not edit this:
Lt1z said:
Im not sure why you would say that? Any and all camshafts are for competition use. Overlap is meaningless with how tests are run. Please edit so people don’t find inaccurate information.

I have done what you requested of me!
You don't sell camshafts for an LT4. . . Got It.

However, the overlap triangle is highly meaningful, regarding not only the tune required of that camshaft, but also serves to bring suspicion to 'some' smog technicians. The smog technician then simply makes a judgement call, and 'if?' in his opinion, the engine idle has been consciously set to high, then even the smog technician knows "Overlap is not Meaningless".

My response to this poster, is the same response I have given to many members in the past. Those who have low post counts, and are looking for help. I simply decided to add a few technical reasons this time, contemplating a few questions which might arise with those reading my response.

However, if there is any valve events, or how they might change the performance of a 'Live Engine', which you would like to further discuss with me, which you might not agree with, simply 'Ask'. . . .

Cheers

 

[Lt1z]

Matt,
Why are you 'Forcing this issue'?

You now going back and deliberately editing your earlier posts?
Some now show no content. . . .

But you could not edit this:
Lt1z said:
Im not sure why you would say that? Any and all camshafts are for competition use. Overlap is meaningless with how tests are run. Please edit so people don’t find inaccurate information.

I have done what you requested of me!
You don't sell camshafts for an LT4. . . Got It.

However, the overlap triangle is highly meaningful, regarding not only the tune required of that camshaft, but also serves to bring suspicion to 'some' smog technicians. If the engine idle is, in his opinion, consciously set to high, as even that smog technician knows "Overlap is not Meaningless".

My response to this poster, is the same response I have given to many members in the past. Those who have low post counts, and are looking for help. I simply decided to add a few technical reasons this time, contemplating a few questions which might arise with those reading my response.

However, if there is any valve events, or how they might change the performance of a 'Live Engine', which you would like to further discuss with me, which you might not agree with, simply 'Ask'. . . .

Cheers

Feel free to DM or email. You seem to not understand what Im saying or why nor have you edited what I asked you to out of the post which is the mis information I was referring to not your overlap pictures. Im not debating what overlap is with you.

 

[Rubber Duck]

Feel free to DM or email. You seem to not understand what Im saying or why nor have you edited what I asked you to out of the post which is the mis information I was referring to not your overlap pictures.

Please cite what I have allegedly written wrong. . .

And also, please explain all of the deletes of your posts, which certainly
tend to help both mask, as well as confuse this issue.

 

[Lt1z]

Please cite what I have allegedly written wrong. . .

And also, please explain all of the deletes of your posts, which certainly
tend to help both mask, as well as confuse this issue.

First sentence of post number 5 in this thread is incorrect and my only concern having to do with this thread.

You can email or DM if you need any other explanation. Otherwise, carry on

 

[Rubber Duck]

First sentence of post number 5 in this thread is incorrect and my only concern having to do with this thread.

You can email or DM if you need any other explanation. Otherwise, carry on

Matt,

Matt, I stated that I was wrong in an earlier post.
I also apologized for making that statement, Oh Maybe. . .1000 times.

If we are good now regarding overlap, then I suggest. . .Let's move on!

 

[Lt1z]

Matt,

Matt, I stated that I was wrong in an earlier post.
I also apologized for making that statement, Oh Maybe. . .1000 times.

If we are good now regarding overlap, then I suggest. . .Let's move on!

Im not looking for an apology. Im asking you to remove that sentence from post 5 so it is no longer there and does not lead to me having to spend time telling people who read it that it is false.

 

[Rubber Duck]

Im not looking for an apology. Im asking you to remove that sentence from post 5 so it is no longer there and does not lead to me having to spend time telling people who read it that it is false.

The terms 'Edit and Remove' seem to carry different meanings between us Matt.