Ecotec Cam Replacement

[positron]

More tech talk..

I visited with the shop that dynoed the Ecotec in the HotRod article because I have the itch for cams next year. The Comp cams mentioned turned out to be a safe hydraulic upgrade and a good solution for a improvement on the upper end. My belief is that the street cams peter off at what is the expected rev limit of 6,500, which we can operate well into that. So I set out in search of a high sustained power band, in the 4,000 to 7,000 range.

It turns out that the off the shelf cam set mentioned is one long and one short cam. So I've been in contact with Comp cams to produce a long/long cam same as the one used for this article (see page two). Found here Article Link

In studying the charts the torque is lower on the bottom end under 3,500 which may not be desirable for the street only folks. Looks like it shifts the peak over to the 4-7k range which is better for where I tend to operate. I don't have any desire to rev over 7k, I don't see the need for it, although I have the valve train for 8k.

Anybody out there beat me to this with any info before I commit? /flame suit on/

*cough* Silver - there are several mentions of more boost = more hot..

[NormLarson]

From my reads of the Cobalt forums Bates Engineering have cam blanks http://www.batesengineering.info/  714-612-3639 or 714-545-0159 for $205.00, I have never verified.  I am going there soon. 

This is a quote that I had saved, "Get a set of 2.2 blanks and get a true set of custom cams made to a perfect grind for yourself.  Just forget about using the cam sensor.  If your really dead set on keeping the cam sensor, then find a machine shop to angle the hex correctly as per GM drawings in the exhaust cam, so you can still use the cam sensor."

Basically the direction that I will head off to with the ported head is finding the GM-R cams or getting Bates Cams and regrinding them to the Comp Cams Blower grind.  Another quote that I saved "Just more base circle is taken off the GM-R's compared to the 272 spec, so the head doesn't self destruct.  Any base circle regrind cam should honestly run the BLE lifters to take full advantage of and be reliable."

I know, ... random thoughts, but, it is all I have yet as you are going into the cam issue before me

[positron]

The theory I'm working with CompCam now is to take the long shaft blank and put the short shaft profile on. Then I should have the best of both. I really don't want to delete any on the sensors.

Also wanting reliability and to stay with hydraulic lifters. At this point I'm wanting plug and play. Crazy cams tend to push the usable power band higher than I operate. Since this is not a drag car I'm after the 4-7k range which is higher than the usual Cobalt high school kid burn out in the high school parking lot.

Also FYI take a look on Ebay there is a slew of GM dealer tools right now, I found the cam holder fixture for this project for like $14. Found almost all tools listed on special tool page for under $200.

[NormLarson]

Good info about eBay!  Have they given you any lift / duration specs?

The factory Cobalt time attack cars track cars used stock cams with adjustable gears.  There may have been a reason for that, I haven't researched yet.  Sounds like you and I are looking for the same power band regardless

[DarthChicken]

The adjustable gears sounds promissing to me... but what to adjust them to, that's the question.  Any idea's what they advance/retard to? Adjusting on they dyno is obviously out of the question with them being under the valve cover.

I'm with positron though - all sensors must still work, the car has to be able to be reliable, and tearing up the head is not ok.

[positron]

There appears to be two schools of thought, adjustable gear timing and cam change. With very few options off the self for our cars which may be the reason for the former. I don't have the time or dyno money to dial in a set of cams. Since my car is a track only car my test time is very expensive so I'm searching for plug and play.

Here's the HotRod cams specs found here.

This is a known grind but on unequal length blanks. Link The link to the camshaft specs goes to the wrong place, I've also told them about that as well.

So it's basically this one from Summit Summit Link But what you'll get is a long and a short cam for the 2.4L

What I'm asking Comp to do is grind this on both the intake and exhaust profiles on long blanks. It's working it's way through engineering..

*Note of caution to stock valve spring folks, I've already upgraded to Bates dual springs and titanium keepers so I can make no assumptions for compatibility to stock springs and durability etc etc..

[silver]

FWIW on a Honda I used to own I did cam upgrade / adjustable cam gear...........gained 0 hp.  it was a N/A application and I was young and dumb and blew $4000 on engine upgrades for pretty much nothing.

[positron]

But what fun would that be.. especially since Bolus is gone to watch spend his money..

[silver]

just throw a smaller pulley on the damn car you WUSS!!!!!!!!!!!!!!!!!!!!!!!!!

hahahaha

old man trying to do things the hard way 

oh wait my car doesn't even start.  still haven't tried to jump it.

looks like i won't be in danger of using too many miles this year

[positron]

I'm not so old  that I can't hear the crickets chirping in your garage..

Step up and buy a charger..

[silver]

yep I wish I could say it's me being lazy but I'm too busy with work that doesn't pay me enough to afford to fix the car right now.


currently at work and will be working through the wekend.

[positron]

being able to be "at work" is a good thing.. 

[positron]

Cams in and relatively sorted out.. car on trailer headed for LS tomorrow.. we'll see..