Nacho SS

iTrader: (4)

Haha exactly man. I like going fast/modding pretty much everything I own

Most likely I'll just keep the MC for DD duty and then fear possible tranny replacements in the future.

06 SS

@NMP went rummaging around this internet place and found this test graph of constant duration/varied LSA: http://www.chevyhiperformance.com/te...ual_plane.html

They don't start the pull until 2500, but theory says the tighter LSA should make more power all the way down to just above idle (and certainly well below the stall speed of our t/c's.)

nmp0098

Nice article, and it definitely illustrates a case where widening the LSA just kills power and doesn't buy anything usable on the top or bottom. That's the problem with speaking in generalities; you are always going to be wrong for some cases. In the text they call out two important points. First, they ran into valve float before the wider LSA would have helped the powerband hang on. Second, they point out that a smaller cam (that was in the 250's for advertised duration) would have shown better the advantages of a wider LSA. But for this case, you are right that its better to just go smaller than widen the LSA to tame the engine.

Anyway, I like something in the 111-113 with about 220 degrees advertised for our engines too. My engine only operates below 2000rpm when cruising at low speeds on level ground. Once the TCC unlocks, the engine tends to rev to around 3000rpm. If you have a fairly loose stall and don't want to spin your engine really high (which requires more expensive parts) you will get better performance with a tight LSA.

Given that, I still have Jesse's Car Craft where they pick up about 50HP with that GT2-3 cam in a 5.3. I'll put up the numbers when I get back from visiting family this weekend. I also think you'll see pretty good mileage with that cam. It may not be the best choice, but its a good cam.

JDMC5

iTrader: (3)

hey, when are you installing all the stuff?

nmp0098

I still need to order some parts (like the cam for one), and I'm trying to get my brother in law to come up for a weekend to hang out and help. I'm probably gonna order the last of the parts next week.

91LT16SpeedFormula

iTrader: (60)

Seems like not many guys have cammed these cars?

I like the cam Mixerda chose but wonder if you could go just a tad bigger? How would I find out what the most you can do w/o issues but yet keep drivability?

New to the LS4 stuff sorry

JDMC5

iTrader: (3)

that depends if you want to keep your DOD or not, if you do your options are pretty limited. If not, your driveablity will probably go before you run into problems. As far as standard cam choices go, you can run pretty much anything the other LS engines run, save for a few exceptions.

JDMC5

iTrader: (3)

sounds good, give me a call when you know what's going on.

nmp0098

OK, so here's the numbers on this cam from CarCraft, using a very similar engine (except for the intake, which is much better than ours). They were running dyno headers too, and they went with Comp 918s once they upped the cam.

Stock LQE (300HP, 9.45:1 All Aluminum 5.3L used in the SSR):
Intake: Stock Truck
Heads: Stock (1.89 intake, 1.55 exhaust)
Cam: Stock (190/190, 114LSA, .456"/.464")
HP: 323@5200
TRQ: 355@4000
TRQ @2000RPM: 318
Vacuum: probably about 24" of mercury at idle

LQE with LPE GT2-3
Intake: Stock Truck
Heads: Stock (1.89 intake, 1.55 exhaust)
Cam: GT2-3 (206/220, 118.5LSA, .571"/.578")
HP: 378@6000
TRQ: 366@4800
TRQ @2000RPM: 308 (less than stock until 3300RPM)
Vacuum: 20.7" of mercury at idle

LQE with LPE GT1-1
Intake: Stock
Heads: Stock
Cam: GT1-1 (229/242, 114.5LSA, .631"/.631")
HP: 413@6600
TRQ: 369@4800
TRQ @2000RPM: 281 (less than stock until 4300RPM)
Vacuum: 10" of mercury at idle

LQE with LPE GT1-1, LSX Intake, Ported Heads
Intake: Comp Cams LSX
Heads: Ported Stockers (2.00 intake, 1.55 exhaust, bump to 10:1 compression)
Cam: GT1-1 (229/242, 114.5LSA, .631"/.631")
HP: 458@6600
TRQ: 392@5800
TRQ @2000RPM: 294 (less than stock until 3200RPM)
Vacuum: probably still 10" of mercury at idle


Notice when the compression comes up and the intake/heads match the cam in being aggressive, you pick up a lot of the midrange that was lost when just the cam was too big.

Here's a link to the second article in the series. You can read about them upgrading the injectors to match the big engine too:
http://www.carcraft.com/techarticles...ine/index.html

Sittingmongoose

iTrader: (1)

Well if this is right for our engines too, i should gain about 50-75hp from the cam i am putting in Lets hope you are!!

GXP25

iTrader: (3)

I always like reading that article.

I can't wait to see the results from the camshaft swaps (along with the intakes).

By the way, isn't the SSR engine known as the "LM4?"

GXP25

iTrader: (3)

I believe this is part 1:

http://www.carcraft.com/techarticles...ock/index.html

DavidGXP

iTrader: (14)

10" Hg of manifold vacuum at idle will make your car very un street-able. That is a bull **** cam and for dynos and track use only. Have fun with your restrictive intake, small tubed air intake piping, shorty headers with a single 3" collector. Small valve heads, small bore and stupid gearing. Peak HP at 6700rpm will require a 7200rpm shift point. Waste!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!

1CL3ANSUP3RSPORT

iTrader: (23)

What do you guys think about Lunati cams?

I've been looking into two of there cams...

Duration
In:204
Ex:214

Lift
In: .420"
Ex: .443"

Lope is 112,and the power band is 1000-5000

Or

Duration
In:214
Ex:224

Lift
In: .443"
Ex: .465"

Lope is 112,and power band is 1500-5500

I'm still learning about cams and wanted to get your guys input,thanks.
Dom

****EDIT****

Part # for first cam listed 10000LK

Part # for second cam listed 10001LK

neilownz

I don't think those are lunati ls cams.

http://www.lunatipower.com/ProductGr...?id=288&cid=60

Part 60510 is the smallest with a .531 lift.

1CL3ANSUP3RSPORT

iTrader: (23)

Ahhh,I saw SBC and assumed it would work out...Ill get the part# tomarrow,I saw it off some ad in a car mag...

nmp0098

I think the easiest way to get started is to look through a catalog, pick the duration to fit the power band that you want, and then get as much lift as the rest of your valvetrain can handle. Much over 0.6" and you'll want to go with dual springs and aftermarket rockers, but under that upgraded beehives and the stock rockers should be fine. There's a ton of things that go into cam design, but that's why most people buy pre-made cams from respected grinders. Whoever you buy your cam from should be able to tell you what else needs to be changed to handle the cam. If they can't, don't buy it.

tomszwajkos

I am considering replacing my Corvair engine with an LM4 aluminum block engine. The only issue is engine rotation. The Corvair engine rotates in the opposite direction. What is involved to change the rotation of the LM4 engine to match the Corvair rotation? I would be bolting the engine to a 1964 Corvair transaxle. I am also concerned about torque. Any suggestions would be appreciated.

06 SS

I would suggest you don't do it. My buddies 'vair twisted the stock frame with it's puny stock air- cooled 6. I can't imagine what would be needed to make it live with 300+ lb-ft.

AlabamaGuy

iTrader: (5)

You'd probably want to do an intake rotation. The big ordeal will be modifying the oil pressure sensing unit to clear the intake neck of whichever intake you're using.