COMP 127550 owners come in here please

[redstangs9308gt]

With the comp 127550 cams, what is your vacuum@idle? Please include what your idle rpm is set too. I am getting ready to remove these cams. They are not adgreeing with my setup for some reason. The car will idle fine, BUT the idle has to be set above 925rpm not to have any stalling issues. This is with Open atomospheric breathers on valve covers and pcv ports plugged off on throttle body. Give all your experiences with these cams and tuning and driveablity please. I am a hundred percent sure I do not have a tune issue.

 

[niner555]

With the comp 127550 cams, what is your vacuum@idle? Please include what your idle rpm is set too. I am getting ready to remove these cams. They are not adgreeing with my setup for some reason. The car will idle fine, BUT the idle has to be set above 925rpm not to have any stalling issues. This is with Open atomospheric breathers on valve covers and pcv ports plugged off on throttle body. Give all your experiences with these cams and tuning and driveablity please. I am a hundred percent sure I do not have a tune issue.

95% of the time, idle issues are tune or dirty throttle body related. I don't have the specific vacuum information you are asking for, but those 127550 cams, properly installed, idle down just fine in my experience......

 

[YoungPony]

Later tonight i'll take the car for a drive and get you the vacuum at idle (I think it's around 10). I know my idle is set at 750rpm. If it's really cold the car will have trouble idling and i'll have to hold the rpms at 1500 for 30 seconds or so then it'll idle fine. When I first got the car back it had problems with idle even when warm and I cleaned the throttle body and it's been great ever since. My car has long tubes and the pcv system is not vented to atmosphere. As far as driveability, so long as it's up to temp it drive good, that's mostly in the tune though.

Joshua Ross

 

[klaw]

My car is around 9" at idle (about 750RPM I think). I have a catch can on the driver's side breather loop (tied back into the inlet after the throttle plate. The Passenger side makeup air is tied into the Whipple tube downstream of the MAF but upstream of the throttle.

Two keys to making these cams work are:

1) As light a spring as possible in the boost bypass actuator.
2) A very good tuner.

Youtube video at idle

 

[redstangs9308gt]

Thanks guys. I am going to move on to a custom set of cams. I am going for the same to better intake and exhaust lift, great idle, more vacuum. I love the lopey idle but if I can't drive my car whats the point of it. Here is my break down information in case anyone ever cares.
1. Idle with pcv system hooked up is 850rpm@10psi of vacuum
2. Idle with open pcv is 925rpm@almost 11psi of vacuum
3. The car is very sensitive at idle. The engine fan comning on surges the rpms down low almost to stall then it will recover back to normal idle.
4. Cams are comning out. I want a custom set but if I can't get it took care of I guess I will go with a 127350, or 127450.

 

[YoungPony]

Just got back from driving my car. Vacuum at idle is right at 10psi (2100 feet above sea level). Sorry to hear you're having so many problems with these cams. I love them in my car, but to be fair, my car is only a fun weekend car. I noticed you mention you are 100% sure it's not tune related. Would you mind saying why you're sure it's not?

Joshua Ross

 

[BruceH]

Thanks guys. I am going to move on to a custom set of cams. I am going for the same to better intake and exhaust lift, great idle, more vacuum. I love the lopey idle but if I can't drive my car whats the point of it. Here is my break down information in case anyone ever cares.
1. Idle with pcv system hooked up is 850rpm@10psi of vacuum
2. Idle with open pcv is 925rpm@almost 11psi of vacuum
3. The car is very sensitive at idle. The engine fan comning on surges the rpms down low almost to stall then it will recover back to normal idle.
4. Cams are comning out. I want a custom set but if I can't get it took care of I guess I will go with a 127350, or 127450.

That's plenty of vacuum. 10psi = about 20 inches of mercury or HG.

 

[tmcolegr]

Are you absolutely sure you don't have a vacuum leak at the brake booster or Evap system?

 

[redstangs9308gt]

evap?

 

[tmcolegr]

Evaporate Emission System

 

[redstangs9308gt]

I am not sure how to test for it. Any common problems that you can point out?

 

[tmcolegr]

Not common problems but if you do have a vacuum leak the Evap system could be a source of the leak you have overlooked. Need to rule the Evap system and brake booster out before you proceed with other repairs.

 

[redstangs9308gt]

Ok, draw me a picture. are you talking about the vacuum line that runs from your manifold to this round looking thing on the driver side strut tower?

 

[tmcolegr]

Yes
That is the purge valve, one of many pieces in the Evap system.

 

[redstangs9308gt]

There hasn't been any codes to come up other than p0191.
I have replaced fuel filter, fuel rail pressure sensor.

 

[Marc s]

Mine idles at 11 inches and my idle RPM is 900. When I first installed the 127550's, the car would sometimes die when coming to idle. My tuner work with the idle integrator and decay rate and now it's fine.

 

[redstangs9308gt]

Well I don't think vacuum is a issue any longer. I started tearing down the engine tonight. I am removing front cover just in case when I pull the valve covers and see all hell broke loose I can remove the heads without delay. I did fine a problem maybe a slight vac leak here but if it is leaking air it must be silent. This is on passenger side, right where the ac compressor mounts up. Timing cover meets oil pan

 

[lito]

Nick, you don't waste any time, lol.

Best of luck with that. Let me know if I can be of any help.

 

[redstangs9308gt]

I love you lito. Thank you

 

[lito]

I love you lito. Thank you

Wait, I care for my reputation here, lol.

Lostsoul will come after me now.