Interested in a sub 220 duration custom comp cam that made 397/391??? I can post a dynograph ....

 

The guy at MTI told me the Stealth I would idle smoother.

 

220/220 is a single pattern camshaft

I wouldn't bother swapping. They are very close...

 

Ok...

I do have some sound clips. I just never got around to posting them. I'll get 'em up.

I *think* that the .571 intake lift listed on MTI's site is incorrect. Mine was supposed to be .581 and I don't see any reason that they would have changed it. Also, both the 220 and 224 XE-R lobes are listed to be .581 unless they've changed that recently.

The Stealth I cam would be a better choice for a stock exhaust manifold car. The Stealth II NEEDS a great flowing exhaust to showcase it's advantages.

The "guy" at MTI was probably a salesperson. Sorry Wayne (guy at MTI that you probably spoke to), but the Stealth II has an LSA of 116 which pretty much makes up for the 4 degrees increase in duration. IMO, if you listened to my car with the SSII (sounds stock at the tailpipe) and swapped cams and then listened to the SSI in my car...you would not be able to discern any difference. The cams are just sooooooooooo close. A little duration here, a little LSA there...it all pretty much equals out in the idle department.

Valvtrain noise, YES there is valvetrain noise with the Stealth cams...or ANY cam that uses aggressive lobes. There's just no getting around it. And you don't have to open the hood to hear it either. However, I don't want to give you the idea that it's loud...it's not, but it IS there. You'll notice it most when the car is idling next to a concrete wall and you have your window down (such as at a drivethrough window.)

 

Wouldn't you agree that a set of shaft mounted rockers like Comp's would quiet things down a bit. Granted it's a big expense, but for a cam that revs till 6800+, I does also have its valvetrain stability factors.

 

I don't think it would help that much really though it's not like I've done this with no other changes with this setup. I once went from stock rockers in the 422 I had to Jesels and didn't notice any difference that I recall. Granted, there was a cam change in the process (went from an R1 to an S1.)

 

I have the Stealth I in my vette (for almost a year now!), and I have virtually no valvetrain noise at all (even with the stock rockers). MTI installs double springs in the valvetrain for the Stealth Cams. After the cam install last year, there was a slight ticking from the valvetrain, but that has now diminished to a level where it's hard to hear it at all!

Idle on my is at 800rpms and silky smooth, only thing you notice is a tiny tiny bit of door shake and that's if you're looking! I have Ti Z06 mufflers so the car sounds stock, idles stock, but sure does'nt run stock!!!

 

Long tubes, catted Y, Magnaflow catback.....In your opinion, are these mods a great flowing exhaust? Hence, good enough for the Stealth II?

P.S. Stock heads

 

"catted Y, Magnaflow catback"

The catted Y is fine so long as the cats are really high flowing ones. The Y-pipe needs to be of good size too. A 3" into a 4" collector does great! A 3.5 " collector will also work just fine if you're not into overkill like I am.

Magnaflow catback? I don't know how well that particular cat-back flows so I can't guess. Better ask a few people who've dynoed it against an open cuttout (a cuttout would certainly suffice.)

 

Would Comp 918's handle the Stealth II's lift and ramp rate? Also would you say the stealth cams have more off-idle torque than say, the TR224? Thanks.

 

since no one else responded to your post I'll bite...

Can you please post the dynographs and the specs of the cam? I could for sure be interested in a cam that can pull these numbers.

 

P Mack, the 918 handle my 231/237 cam so yes I would say they can handle the Stealth cams. Of course, next time I will install some stock dia. duals so I can swap out any cam I want.
Off idle torque, I am not sure on.

 

The cam is a Comp Cam XE-R
216/216 @ .050
.588/.588 w/ 1.7 rr
114+2 LSA
112 intake center line

The blue line represents the cam with the following mods (basically full bolt-ons):

1. [*]
2. [*]
3. [*]
4. [*]
5. [*]
6. [*]
7. [*]
8. [*]
9. [*]

The red line is the same as above but thru manifolds, ORY, and cutout



Notice the tip in issue ... most noticable on the Torque graph. You can also see there are several flat spots in the graph as well. I think that comes from the ported MAF ends causeing the computer to go into a Burst Knock condition. The reason I think it's Burst Knock is because the PCM is reporting no knock retartd throughout the run, but I do notice dips (6 degrees or so) in the timing curve. I don't think there's much more power left in the cam (without heads) due to tuing, but I think I can further smooth the timing and torque curves.

 

those are awesome numbers for such a small cam!!! How does it idle? (could it pass as stealthy?)

Also, what headers are you running?

I'm assuming its a M6 car with a LS6 intake

Again, very sweet!!!

 

It idles very, very smoothly at ~850 rpm. Most don't know I have a cam except for the light valvetrain noise. Around town driving is a dream and I usually get 20+ city mpg with 29+ hiway mpg.

The headers are Jet-Hot.

And yes, it's a M6 and 2002 YM so it has the LS6 intake.