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Fuel economy...downside. Love...upside. Cost...downside. Love...upside.

See my signature
 
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In my signature...Matt's GPTuning 2.5 with upgraded valvetrain mods. Just got back from a 4th gear pull on a quiet highway and hit ~200kmh. Pulls like nothing I've ever driven at elevated speeds, and that's with factory heads!
 

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In my signature...Matt's GPTuning 2.5 with upgraded valvetrain mods. Just got back from a 4th gear pull on a quiet highway and hit ~200kmh. Pulls like nothing I've ever driven at elevated speeds, and that's with factory heads!
Go onnnnnnnn. I'm listening.

At some point I'll be looking camward.....
 

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Go onnnnnnnn. I'm listening.

At some point I'll be looking camward.....
I have his stage 2 because it isn't as lopey.
 
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Go onnnnnnnn. I'm listening.

At some point I'll be looking camward.....
I liked a bit of lope at idle and I prefer to drive at elevated engine speeds no matter what gear I'm in. Talking with Matt, his 2.5 seemed like the best fit for me, and especially for when I save my birthday money and get better heads.
My initial tuning required some driveability tweaks because of some low rpm bucking, so now I have no issues. It's got the get up and go torque punch that pushes you into the seat, and that's exactly what I was looking for.
Others complain about mileage......it wasn't good to begin with, so what did you expect by putting in a more aggressive profiled cam? 😄
 
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Video of the idle?
 

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I have found 2.5 is the right choice for about 80% of the SBE LSA guys. A couple outliers will be more suited to Stage 2 or 3.
I had my reasons for going with his stage 2 cam and I'm very happy. My goal/expectation was very low 11s (11.1) and I'm on the 10s before E85. Sound clip in previous post.
 
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I had my reasons for going with his stage 2 cam and I'm very happy. My goal/expectation was very low 11s (11.1) and I'm on the 10s before E85. Sound clip in previous post.
Not that I do 1/4 miles, I like to just punch it on open road, I won't know my 1/4 mile time until I install the G-Force axles with 11" rears.
 
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Video of the idle?

This was in the fall of 20 I think. Don't mind the lid fittings, I had to cobble some fittings together while waiting months for the proper 90* ones. :rolleyes:
 
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Blown376,

Have you done paint correction? Just curious as it looks awesome!
 

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Blown376,

Have you done paint correction? Just curious as it looks awesome!
Thanks! BR is not for those who shy away from work.
I did it once with a 2 step correction using Chemical Guys V series of pads and compounds/polishers, then a sealer and glaze, plus 2 coats of Swiss Vax. It was overcast, so black does look better in that flat light. It's due for another one before summer starts.
IMG_20150813_121922.jpg
 

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Do it.

One could argue its "maintenance" to replace the GM lifters, rockers and timing chain.

Sent from my SM-G991U1 using Tapatalk
 

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Increasing the airflow through an engine should produce
about 1.0 fwHP for every 1.5 cfm the engine inhales.

-making a few assumptions-
Assumptions such as the cam lobe is symmetrical, and the
lash ramps and flank acceleration rates are the same, and
the engine has sufficient compression, as well as the cylinder
heads flow sufficiently, etc. then. . .

An LSA 376 CID Engine, having a 2.165” valve, will have a
circumference of 6.80”.

The Stock LSA has an intake lift of 0.480” at the valve,
The stock LSA has duration, at 0.050” of lifter rise of 198°.

-on an na engine-
If the valve lift is increased to 0.600”, and the duration is
increased to 231°, then the air supply can be increased by
about ~296 CFM.

That could amount to a fwHP gain of ~197 fwHP.

Most usually though we will apply an efficiency coefficient
to the CFM, amounting to anywhere from 85% to 92%,
depending on the calculated efficiency of the engine.

The above coefficient values fit well built Street / Strip cars,
on up to all out performance engines.

However, street cars fall can fall below the 85%, as they don’t
have such things as sufficient static compression nor cylinder
heads which flow well, especially at the higher valve lifts.

Those types of inefficiencies then negatively impact the potential fwHP. . . .

To further calculate for additional fwHP improvements
from an FI Engine, then you simply multiply the above
CFM values, by the density ratio change, which is related
to pressure and temperature changes within the cylinder.

While we tend to use CFM on this forum to relate to air flow,
or the CFM Flow Rate which relates to the volume of air flow,
another term used to define the above is Mass Flow Rate, which
relates to the weight of the air, which is given in Pounds over time.

Cheers,
RD
 
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One could argue its "maintenance" to replace the GM lifters, rockers and timing chain.
This is going to be my exact "justification" for it as I get closer to 100K. :)
 
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