TableLeg

Can anybody confirm or deny that this is the LS2 cam used in the carcraft article?

http://www.gmpartsdirect.com/results...umber=12574519

I don't know if there is more than one LS2 cam and the price for that is crazy cheap compared to the aftermarket.

TableLeg

Can anybody please comment on how you think this cam would perform compared with some of the others we have discussed? Especially the exhaust duration at 230.

Emissions Friendly Camshaft for LS1 & LS6 Engines
218/230 | .59x”/.60x” | LSA117+2
-10* Overlap
Basic Operating RPM Range: 1400-6200
Expected Horsepower Gains: 20-30RWHP over the stock camshaft in a well-optimized setup
Aftermarket Headers Required: No (although emissions-friendly headers will allow maximum power gains)

99Bluz28

iTrader: (35)

You'll probably only notice gains above 5000rpm.

TableLeg

Thanks 99Bluz28 for the reply,

Still trying to get my head around all these cam numbers and how they interact with each other.

Could you please explain why you believe I'd likely only see gains above 5000rpm?

Is it the lift? the duration?

I'm very interested in trying to understand how this works.

I thought that the 117 LSA would give it a very smooth stock like idle, and I thought that the exhaust duration at 230 would benefit the restrictive exhaust port.

Like I say I would like to understand what is going here better.

rigid

iTrader: (5)

I recently went to a much smaller cam in my car. I had never really liked the stink of mine from all the overlap. Plus I had been searching for jobs out of state, and fearing I would have to pass a sniffer test I went with a cam that could most likely pass emissions. I went from a cam with +11 overlap to one with -9. I tested mine with a handheld emissions analyzer, untuned, just to see where it came in. And as long as the catalytic converters could get up to temp my emissions numbers were pretty low. Anything in the -8 to -10 of overlap range should really have no problem passing. Any more than that and you will have problems passing CO or unburnt hydrocarbon tests. You'll need to make sure you have a good tune, make sure it can go closed loop, make sure your air/fuel ratio is switching around stoich, and make sure the catalysts are close enough that they can get to temp. If you can manage all that you should be fine.

The cam I went with is a 226/228 on a 118+2.

I have a bit more displacement than you, but here are what my numbers looked like on my car:


If the car just warmed up and I didn't put any load on it, the emissions stabilized in the 400-500 PPM range. But get the catalyst hot and they started doing their thing. You can see I also tested the emissions inside the car, I used to have some leaky headers and the exhaust would come right in the cabin. Those numbers were just to make sure I wasn't still getting fumed out.

And just for comparison sake I also tested my 2013 WRX:


My combustion temps are probably a lot higher on the LS leading to the higher NOx numbers, but it could also be a lot of other things, such as the fact I tested the car without a tune after putting in the smaller cam. Or it could be the catalyst wash coat is probably much better on the OEM Subaru catalyst over the high flow ones on my other car.

I would suggest you get something custom ground. I had my cam custom spec'd by Geoff at EPS and I'm real happy with it.

TableLeg

Rigid,

Many thanks for that reply especially taking the time to post up those emission results pictures

Blackpanther99

iTrader: (8)

Ls6 or LS9 cam.

99Bluz28

iTrader: (35)

It's the wide 117lsa combined with the wide split. IMO, I'd drop the exhaust duration down, the lsa down and give it another 1* or 2* advance, along the lines of a 218/228 116lsa +3 or a 218/226 115lsa +3. You might be perfectly happy with the 218/230 117lsa+2 ,but I really don't know for sure.

TableLeg

Thanks again 99Bluz28 for the reply,