Colt Stage II cam community dyno vote

darkhorse said:

For what it's worth, I have pulls with my car that compare the stock cam with the Colt Stage II. Not much change in peak but considerably broader curve.

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Sweet, that was mostly what I was interested in.

Could you please post / link to Dyno? I am interested.

stock cam

Colt cam

Do you have any higher-quality images? Can't even read the numbers.

So I managed to backtrack those images to your pics account on the forums and look at the less-lossy JPEGs. I have mirrored the imaged on my server and if you click the code you'll be shown the graphs he posted.

Stock Cam

Code:

Date of Pull:	May 3rd, 2012 @ 12:11
Peak Trq:	319 ft*lbs	Avg Trq:	277 ft*lbs
Peak whp:	194		Avg whp:	165
RPM Range:	2000-4200

Almanac Data
Low:	59°F
Mean:	68.7°F
High:	79°F
Press.:	29.79"

Colt Cam

Code:

Date of Pull:	September 20th, 2012 @ 13:08
Peak Trq:	310 ft*lbs	Avg Trq:	242 ft*lbs
Peak whp:	198		Avg whp:	144
RPM Range:	1600-4400

Almanac Data
Low:	50°F
Mean:	57.4°F
High:	66°F
Press.:	29.87"

darkhorse, your dynos have some validity, but they're less applicable than what we're going for, mostly because they're for a PD engine not the VE engines, aka commonly the 1Z and ALH, which is what we'll be testing it against. They're also done months apart thus unstrapped from the dyno. This has been noted in long standing to cause variations in the results.

Here is ValiPowder's old chart comparing the 3 with basic profiles:


TDIMeister's data:


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In other news, I have an updated tune from my tuner correcting a couple of things and prepping for the dyno day. Small stuff that I've adjusted my right foot for, but will cause variations in the dyno.

I'll need to check with him again to see if he can adjust the MAF to where we can pull applicable data from it, though asking about adjusted tune for the cams, he's in the same ball park as I to where the effect of the cams should be done with 1 tune and see what the output changes are. Yes, EGTs and smoke typically go down, but making them go back up again to account for the better breathing is just another perspective on the same data.

Just so you guys know, and I'll produce the procedure used when all of the data is collected, I'll be keeping the same lifters that I installed in the car 20K miles ago and the shop does have a WBO2 sensor available. Localized weather collections of temperature, relative humidity, and barometric pressure will be done for each dyno run along with other data logging, which still needs sorting.

I'm also waiting on a replacement socket for my burner because a pin became irreparably damaged and I cannot burn the new tune . I might have a surprise on the dyno day too, but I'm not sure of the specifics just yet so I'm keeping quiet. Yeah, this is a tease, deal with it.

Your observations are valid but the shape of the torque curve is the pertinent factor. The power comes on sooner & lasts longer. The stage 2 is not billed as a performance cam but an improvement over the stock in durability.

darkhorse said:

Your observations are valid but the shape of the torque curve is the pertinent factor. The power comes on sooner & lasts longer. The stage 2 is not billed as a performance cam but an improvement over the stock in durability.

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Emphasis mine.

True, and that was the issue with the PD cams to begin with.

As for the shape of the curve, with everything not behaving properly, mine isn't too dissimilar to yours with my OE cam:

looks like the lower two curves are the stock engine hp and tq readings

What would you guys like to see if someone was kind enough to donate a Dbilas 260 to testing as well?

DC-
I'd be interested to hear how you plan to accomplish the advance/retard of the cam. Can you shim under a cam lock on one side to rotate it one way or the other? Will that be enough? Seems like with the pin in the IP, rotating the cam instead of the crank might be easier? Even that 2 tooth 5.4 degree flywheel rotation would translate to 2.7 degrees camshaft rotation which you might be able to do with shimming the cam lock.

Well I found you can't do it with shims under the cam lock. On a 1Z the ALH Colt II when straight up has room for .003" feeler gauges under each wing of the lock plate. I got mine straight, then bolted a degree wheel to the snout with a wire pointer. I then removed the lock, and advanced the cam (clockwise) 2 degrees or 4 crank degrees. Now I just have to fabricate a 2 degree angle locking plate to hold it still when putting the timing belt on and for checking it after.





My understanding is that for these cars with mild (like mine anyway) mods, advancing the cam a degree or two (cam degrees) is beneficial to mitigate against the loss of low end. I have a Franko6 AHU Stage II cam too that I will switch to after I drive the Colt for a few thousand miles for comparison, but it won't be on a dyno. I'll be interested to see how yours does.

Yblocker,

Do you have any specs for the Frank06 stage II cam? Wondering how they compare to the Colt stage II cam. Anyone have that information?

It's funny, Yblocker and I have been discussing that very thing offline recently.

I only have rough measurements anyone can take with a mic. The Colt lift (lobe height) is at about .363" while Franks is .360". The base circle of the Colt is at about 1.500" while Frank's cam comes in at 1.440". Frank's cams are re-grinds so the reduction in base circle is needed to re-profile the lobe and get the additional lift. The lobe separation would be the same for both. Further up in this thread (post #34) the intake and exhaust open/close timing is listed in the table for the Colt. I don't know what Frank's are and I think maybe he's reluctant to share that information.

If someone could send me an aftermarket cam, then I should be able to get all the measurements, angles, and visual comparisons. I already have a stock cam in my spare head so if interested then I can test this and show the results.

Looking at the dyno for the Stage II, granted the shape is a little better but you're giving up some tq and hp, not exactly what you'd expect,

The stage II is touted as a performance cam.

There were several things off with that dyno. The pulls that'll be completed this month will give more definitive results hopefully.

Ok, sounds good.

I know I had a bad lobe with the stock cam but the stage II made a noticeable difference in the way she ran, I like it.

turbovan+tdi said:

Looking at the dyno for the Stage II, granted the shape is a little better but you're giving up some tq and hp, not exactly what you'd expect,

The stage II is touted as a performance cam.

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I ran across some old posts by Chill. He had been testing the Colt Stage II cam and said it cost a couple of horsepower. Don't know if that was definitive or preliminary. That I why I am interested to see the cam tests on the same car, same day, same dyno, and the same tune.

The real question is what EGTs are at. 2 hp loss and a 200° EGT decrease probably yields more than 2 hp once the fuel is turned up to use the extra air.

john.jackson9213 said:

I ran across some old posts by Chill. He had been testing the Colt Stage II cam and said it cost a couple of horsepower. Don't know if that was definitive or preliminary. That I why I am interested to see the cam tests on the same car, same day, same dyno, and the same tune.

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That would be interesting.

Colt stage 2

I have seen 10hp increase results on a pd with colts stage 2 cams.The profile of the stock cam is too aggressive hence the excessive wear. (Omega renegade)

I've not used the Arduino platform before, but with my background and what online it shouldn't be too hard to cook something up. Here are the localized hardware specs of the electronics that I will be logging from:
MPL115A2 - barometric pressure - 1.5 mBar accuracy
HTU21D-F - relative humidity & temperature - 2% RH accuracy, 0.3°C accuracy
MAX31855 - K-type thermocouple - 2-6 °C accuracy depending on probe
Aircraft Spruce's EP132 EGT probe

I'll need to talk to the shop in person to see if there is a way they can timestamp RPM for me so I can correlate EGT to RPM as it won't be a simple linear fit.

Time to break out the hot air rework tools and the Arduino suite for some USB data logging. After tomorrow's events and the collation of data, I'll be posting the results in FUB's thread, Camshaft Data.

It's definitely easy to log with the arduino. I just spit out a CSV file to the console and have that saving you disk. Simple!

I guess getting an RPM signal is a little more difficult. There are plenty of places on the car to get it but they're all being used by the ECU already. It would be fairly easy to build an optical tach with an Arduino using some reflective tape on the IP pulley or harmonic balancer?

I'll warn you the Adafruit MAX31855 library is brutally slow in its stock form. You're not doing closed loop control so it probably won't matter. It wastes 65ms per reading, mostly just in delays. It can read in less than 1 ms though.

I'll tap it with my scope or meter later to see if its 5V or 12V. I almost picked up the gear from SparkFun, but the sold out of two of the boards the day before my order. I like their home-spun atmel board with native USB instead of going through a FTDI chip. Coulda used a PIC32MX I have on hand, but I've not have time to spin a board and it's quite a bit of overkill. This'll be sufficient and this Metro board is running at 5V.

I just love reading things in foreign languages, even if I don't understand them.

I consider myself fairly intelligent but you guys are geeking out on a whole different level.

Abacus said:

I just love reading things in foreign languages, even if I don't understand them.

I consider myself fairly intelligent but you guys are geeking out on a whole different level.

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Yes, you can blame me for getting DC started on this stuff at an early age lol well dad & myself. Either way, I find it interesting to see whatever language he speaks, written down on the forum. Fairly quantifiable data & theories posted here.


Sent from my iPhone.

For the sake of completeness, you can find the results here:
OE Camshaft
Colt Camshaft
Dyno Notes & Files
VCDS Logs