ez2cdave

GUYS,

I am looking for a cam that will provide very high torque in a broad, flat band with a lot "under the curve" ... 6000-6500 RPM MAXIMUM ... Looking for long component life, reliability, MPG, and street-able POWER & STEALTH !

SPECIFICATIONS

(1) APPLICATION:

1995 Pontiac Trans Am (full weight), 4L85E A4 Transmission, Strange Engineering 12-Bolt rear end with 3.08 gears (3.42 - 3.73 ONLY if absolutely necessary), 25.66" diameter rear tires (315/35/17), Kooks 1 7/8" long-tube headers w/cats, Magnaflow Cat-Back exhaust system ... K-Member swap, etc, etc, etc.

*** Car MAY have to pass emissions, if I ever move to another state ... Visual only, for now, in NC for 1995 and earlier model years !

(2) ENGINE COMPONENTS:

BORE 4.125" X STROKE 4.000"

LS7 Engine Block, ARP studs throughout, CNC LS3 Heads (2.165" / 1.59" LS3 Valves), Callies "Dragonslayer" 4340 Forged Crank, Callies 4340 H-Beam Rods ( 6.125"), MAHLE pistons (11.1 CR w/ 70cc), Comp Cams Ultra-Pro Magnum Rockers (1.8 Ratio), F.A.S.T. 102mm Intake w/ 102 mm TB, 42lb.hr fuel injectors, etc, etc, etc.

(3) CYLINDER HEAD FLOW SPECS: (CFM)

.200 .300 .400 .500 .600 .650

INT 153 225 280 324 350 355

EXH 118 180 201 217 230 236


(4) CAMSHAFT:

I have been considering the following cams:

LINGENFELTER GT-11 215/231 @.050" .666"/.680" w/1.8 118 LSA

KATECH TORQUER LS3 224/236 @.050" .615"/.636" w/1.8 113 LSA

KATECH TORQUER LS7 220/244 @.050" .651"/.686" w/1.8 110+4 LSA

E.P.S. LS 214/232 214/232 @.050" .640"/.633" w/1.8 117 LSA

E.P.S. LS 222/242 222/242 @.050" .632"/.640" W/1.8 117 LSA

CUSTOM ???

I would especially like to hear from Patrick G. and other custom cam "guru's", but everyone is welcome to add their thoughts.

Remember these are CNC LS3/L92 heads, not LS7 or "aftermarket", per se . . .

Thanks,
Dave

ez2cdave

...... ..... .... .....

Patrick G

iTrader: (14)

A 7.0L is going to want 12-14 degrees more duration than a 6.0L would. Most 6.0L stealth cams are around 215-220 duration on the intake side with a small split to the exhaust to keep the overlap low. With this in mind, I'm wondering why you're looking at these cams with tiny intake durations and big exhaust durations? That's not really the stealth approach.

I'd recommend something around 230 on intake and between 230-238 on exhaust with a fairly wide LSA to keep the overlap low and the chop less dramatic.

ez2cdave

************************************************** ********
Hi, Patrick.

My interest in those cams began with the GM High-Tech Performance Magazine article "Battle of the Bumpsticks" . . . They tested various "street cams" on a 6.2L LS3 crate motor. (Link Below)

http://gmhightechperformance.automot...son/index.html

I like the smooth idle characteristics ( less than 35-40 kPa MAP @ idle ) and ability to pass emissions, if necessary ( the LPE GT-11 has a -13 deg. overlap).

I am looking for a smooth, quiet, "near stock" idle with massive torque right off idle and having a broad, flat torque curve. Maximum RPM would be 6000 - 6500 and I don't want to have to run steep gears or a high-stall converter.

Basically, a "sleeper" that is definitely the wrong car to "try" at a stoplight, without "tipping my hand" to the other guy or every cop I end up next to in traffic.

The "EPS" cam lobes sound very interesting, but I don't know anything about them other than the little I have read online. Can you please tell me more ?

************************************************** ******
From what you said, it sounds like you are thinking 225-230 / 228-238 @ .050", right ? What about LSA (113-117) ?

Given the head flow data, I am thinking lift to be .600"-.650" w/ 1.8 ratio rockers . . . Does that sound right to you ?

What EPS lobes are available ?

Do you have any "ballpark numbers" for torque & hp, as well as RPM range for this combination ?

I am thinking between 550-600 ft./lb. max.torque . . . HP will depend on Torque at any given RPM, of course. Peak HP is not my goal, at all !

************************************************** ******
Many Thanks,

Dave

ez2cdave

Patrick,

After looking at the EPS website and this cam and its specs, it looks like a custom cam is the only way to get what this motor truly needs .

http://www.engpwrsys.com/index.php?a...&productId=109

Does EPS have a list of cam lobes to choose from ?

I just want to be sure I get it right the first time, since camshafts are something of a "black art" to me .

Thanks,
Dave

Patrick G

iTrader: (14)

The cam you need does not exist on anybody's shelf. It's going to be a custom cam for sure. The EPS lobes work very well with 1.8 rockers and the valvetrain components you spec'd. If you'd like me to spec you a custom cam, just click the cam help link in my signature and follow the instructions.

Oh4GTO

iTrader: (46)

The Katech Torquer would fit the bill for torque and near stock idle.

ez2cdave

************************************************** ********

TORQUER LS3 or TORQUER LS7 ?

Dave

Oh4GTO

iTrader: (46)

LS7. Ive seen a lot of dyno graphs on these and it is nice. Katech also runs these throrugh their spintron and picks proper valve springs (beehives in this case) for best valvetrain stability.

Patrick G

iTrader: (14)

Some of you guys are thinking that the LS3 needs some kind of wild 15-20 degree split between intake and exhaust. This is not good thinking for this application. Remember, he's got a large motor, but limited rpm range. A smaller split to the exhaust will allow him to run more intake duration (which will help overall power) and run a smaller exhaust event which will keep overlap lower (improving street manners and stealth).

Stage7

iTrader: (1)

Have you heard the Katech torquer cam at idle? Not stealth.

Ryne @ CMS

iTrader: (10)

i would do a 231-239 or 231-235 on a 115+2/3, this is a off my head guesstimate.... if you want more stealth drop it into the 220's on the intake

smok'nZ

iTrader: (160)

who cnc'd the heads

ez2cdave

Hi,

Sorry to have dropped out of the thread. I pulled some muscles and partially tore the collateral ligament in my right knee, playing softball on Friday.

The heads are the SDPC (Scoggin-Dickey Performance Center) CNC LS3 / L92 heads.

http://sdparts.com/details/scoggin-d...-center/sd8800.

Dave

ez2cdave

Patrick,

I am going to fill out the form and get you to spec out a cam for me, but I have a favor to ask.

If it wouldn't be too much trouble, please spec out both a 427 (4.125" x 4.000") and a 454 (4.200" x 4.000"), both with the same 6000-6500 max RPM, as there is a chance that I may be able to pick up an LSX block for half price !

All other components will be the same.

Thanks,
Dave

pink_bits

Is that price for one head or 2???

ez2cdave

That is the price each, $750 . . . So, $1500 / pair

Flow numbers basically equal the LS7 heads, but a LOT cheaper !

Get their catalog, it's free.

Dave

ez2cdave

Would there be any cam spec changes required for a cast-iron block vs. an aluminum one ?

I am thinking in terms of detonation, etc.

Dave

RyanSws6

iTrader: (72)

Pat spec'd a cam for my 408 with LS3 top and nailed the idle I was looking for! For sure you'll need to go custom cam. He spec'd it 9mos ago and slid it in couple weeks ago and love it. You'll pull more because of the extra cubes you have. For sure I'll be close to mid 500s n/a...once I get my good tune in...

ez2cdave

Ryan,

Thanks for the info . . .

That is a very nice-looking ride !

Dave