Econo camshaft?

[06T200]

Since there are 2 different cam profiles specified in the manuals depending on what manual, some list the camshaft lobe lift as 7.2mm, and some list the lift at 8.51mm. While I had my 06 Aveo LS apart, I measured everything to make sure nothing was off spec, and the cam lobes measured 8.51mm on both the exhaust and intake cams. Both cams are the same grind as well. So I am not sure what lumps the 7.2mm cams come in, but I assume earlier Daewoo 1.6's - such as a 2001 Lano's is one application that used the 7.2 cams from what I have found in the bone yard.

My question is, (if anyone has even noticed the difference in cam profiles) has anyone tried swapping in the smaller 7.2mm cams into an Aveo to see if the MPG's improve. I would think one would see a pretty noticeable difference in efficiency, but im not sure what this would equal in terms of MPG. Just throwing the idea out there, a search found nothing on the topic, at least not in the context of economy.

Thanks

[joshwasataylor@gmail.com]

@06T200 that sounds like it's worth a shot.

[iceman]

would one be for cars with a/c and one for cars without? I know some older cars had a grind to compensate for power loss of the compressor.

[Daox]

They compensate for A/C use by increasing idle rpm these days.

[MetroMPG]

I've done this in my car ... but not an Aveo, sadly:

It's in the pre-Aveo... when GM's previous entry level model was the Chevy/Geo Metro.

Even though the car was already pretty efficient, they did an even more efficient "XFi" model with an economy cam and a bunch of other features like taller final drive gearing, 1 less piston ring, revised ECU, etc.

Someone I know spotted an XFi in the junk yard and pulled the cam out of it. I dropped it in my non-XFi Metro (Firefly, actually... Canada only variant same as a Metro).

The cam shifts the torque peak lower down the rev range, and you can feel it. It works well with taller gearing (I've swapped my final drive ratio as well), meaning you can upshift sooner and cruise in taller gears without bogging/downshifting as early.

The difference in the cams is lower lift, lower duration & advanced timing:

XFI Model
Standard camshaft lobe height is 39.628 to 39.788 mm
(1.5602 to 1.5665 inches).
Wear limit 39.528 (1.5562 inches).

Base and LSI Models
Standard camshaft lobe height is 40.415 to 40.575 mm
(1.5911 to 1.5974 inches).
Wear limit 40.315 mm (1.5872 inches).

Also, the XFi cam is "6 degrees advanced from the stock cam, based on measurements of intake centerline."

[06T200]

Apparently the smaller cams were for the 1.4 lumps, and they both use the same head casting. However I have still yet to find one over here in the states. The XFI metro days is where I got the idea in fact! lol (shamefully I still have a rag top metro with an XFI setup sitting in the shop).

Metro MPG, you are the KING of MPGeeez and a past record holder if I am not mistaken..? Not to toot your horn, but many in the auto world look up to your accomplishments to say the least.

[MetroMPG]

Oh stop. No records that I know of, but I've done well in a few economy competitions.

XFi convertible... nice! I picked up a vert a couple of years ago too which has been sitting in the garage awaiting work. Only 100k kms on it (60k mi), but the floor is rusted out pretty badly. I will need to brush up on my welding abilities before it's roadworthy again. Oh, plus find the free time among all my other projects. I don't have the econo cam for that one, but I do have a 1.3L SOHC swift 3.5 final drive transmission.