VidViper

OK, I've got a 98 Vette (A4) with a Vararam, ported LS6 manifold and TB, LG Pro headers, and 3.73 gears.

The 853 heads are going to be ported, and I need to decide on a very mild cam. I am primarily looking at an LS6 cam or the LPE GT2-3 cam. Can someone approximate performance numbers for both setups? Preferences and all input appreciated.

I know there are better head options out there, but I have reasons for going the way I am going on the heads. I just need advice / details on the cams.

Thanks guys

Bounty

Same vehicle...1998 A4. Currently has an LS6 intake, LG longtubes, ZO6 Ti catback, K&N FIPK II, and a tune from Norris Motorsports (yes, that Norris). It currently dyno's at 338 rwhp.

After a long conversation with both my tuner and installer/close friend going over my needs, wants, and desires for the end product we decided on a package with the LPE GT2-3 camshaft and P&P'ed 243 casting heads. The heads are being milled to produce 62cc chambers giving a nice little compression bump. You can't go to the 59cc heads with this camshaft as it raises the dynamic compression ratio a little too high for 93 octane pump gas. Of course this includes all supporting mods...i.e. ported oil pump, upgraded valvetrain, etc.

Both have told me to expect in the range of 45 to 50 rwhp increases after final tuning putting me in the 380 - 400 rwhp range. Figure with the LS1 heads you might be a few ponies down from there depending on where you started from. It's not unreasonable to expect an additional 40 rwhp or so from your combo.

And for some free advice...add the 3.42 gears at the same time. Even without a converter it will help you get into the upper rpm's (where you make power with the GT2-3) much faster and keep you there between shifts. Good luck and let us know how it turns out for you...

redazz

i have a 99 6spd coupe with gt2-3 ,ls6 intake and exhaust manifolds, stock ls1 heads with 918 springs and a tune by 21st century muscle car.i got 365 rwhp 360rwt

idles like stock with just a little lope.zero issues after 20k miles
john

californiakid

I just ordered that cam for my 2001 Z06 after speaking with one of the tech guys at LPE. I informed of my desires and future plans for my car (Maggie install) and he said with the LPE GT2-3 cam alone you will pick up around 20-30HP, but with the addition of a blower they have seen packages net anywhere from 520-540 crank HP with a Z06 and that cam.

It idles like stock and allows you to keep a stock tune if you want to, if you are racing though the springs will need to be replaced every 10-15 thousand miles otherwise the high lift of this cam could cause a spring failure. It passes emissions and is a sleeper cam as well, no one will be able to tell I have a cam in there until I start hitting above 3,000 rpm and it pulls like a scalded rabbit.

Keep us up to date on when you install it. I will do the same. I have only seen one video of the GT2-3 cam in action, a guy at the GTO forum does an idle and a rev on angelfire or something like that.
Ciao,
Californiakid

californiakid

Forgot to add that I have a 2004 Z06 motor in their now. I was not looking for anything to crazy either, been there done that.
Ciao,
Californiakid

Bounty

Not sure where you got this info but the lift on the LPE GT2-3 camshaft is below .580 lift meaning you can actually use the stock ZO6 yellow springs. A set of Comp 918's will definitely insure you do not need to change valvesprings every "10-15 thousand miles" as it is not considered a "hihgh lift" camshaft at all.

Don't let someone talk you into spending more money than you have to...

californiakid

For racing purposes, I would not leave springs in there for a long time with pretty much any cam. I have changed my 02 Z06 LS6 spings every 12,000 miles when I was using the GM Hotcam, even with a very low .525/.525 lift. I started doing this because of my real world experience in previous configurations and racing. The LPE GT2-3 cam can use the same 02-04 Z06 spings as well and for the street great, but as any experienced racer will tell you any abuse in the valvetrain from racing will eventually warrant a spring change, where that spring life lies is the question.

I personally broke Comp 918 spings consistently when I was using the Katech racing cam with a .581/588 lift. I DO RACE AT HOCKENHEIM OFTEN and have experience with with 01 Z06 cams, 04 Z06 cams, GM Hotcam and Katech cam.

My test bed is Hockenheim, Germany and the autobahn. I know that the GM hotcam and the 01 LS6 cam were the easiest in the valvetrain at high rpm, whereas the 02-04 LS6 cam is harder and so is the GT2-3 cam.

When doing a cam swap it is just good practice to change the springs anyway, and that is a personal decision.

If the original poster is not going to race, then a set of 02-04 LS6 springs are what LPE recommends. You can choose what ever floats your boat, but just be aware of how you will drive the car and to what pain level you will be willing to accept later on because of a spring failure if you decide to race and pound the valvtrain. It happens to factory spings as well. If GM was willing to increase the spring rate to accomodate a .551 lift or something like that, then a .580 cam and racing would dictate some common sense.

LPE GT2-3 cam specs:
LPE part #: L210085297
Engine(s): GM Gen III & IV V8 engines except Displacement On Demand (DOD) & camshaft phaser applications
Firing order: 1-8-7-2-6-5-4-3 (per standard GM V8 cylinder numbering)
Intake Exhaust
Valve adjustment: HYD HYD
Lobe lift (inches): 0.337 0.341
Valve lift (inches): 0.573 0.580 with 1.7 rocker ratio
Valve lift (inches): 0.607 0.614 with 1.8 rocker ratio
Duration @ 0.006": 254 281
Duration @ 0.050": 207 220
Lobe Separation Angle (LSA):
Degrees of advance:
Valve timing @ 0.050" tappet lift: Opening Closing
Intake -16.0 BTDC 43.0 ABDC
Overlap angle -23.4
Exhaust 47.6 BBDC -7.4 ATDC
These specs are with cam installed at: 119.5 intake center line 117.5 exhaust center line
Recommended installation angle: 119.5 (intake center line angle)
Recommended valve springs: GM 2002-2007 LS6/LS2 valve springs (90 lbs seat/290 lbs open) 1.7:1 rocker applications
Comp Cams 26918 valve springs 1.7 or 1.8:1 rocker applications
Comp Cams 26928 valve springs 1.7 or 1.8:1 rocker applications
Notes:
LPE recommends always degreeing in the camshaft to confirm the camshaft location.


Have fun and remember modding can be an addiction, so be careful. I started with headers, not enough, then the katech head and cam package, blew a spring and shot up a motor, new motor GM hotcam and ported LS6 heads, DRM coolers for the tranny and diff, harnes bar, Hurst shifter, ram air, high flow cats, straight pipes, custom tune in Swizterland by a Callaway C12 company HeinzRoth Racing, DRM radiator with engine oil cooler, T1 suspension, Movit racing brakes, Autometer Cobalt gauges galore, and the list seems not to stop, carbon fiber roof, rear wing, custom race alignment for the Race Days at Hockenheim, usually the Vette/Viper shootout, highest placed was 4th.

I tend to change cams and depending on the event. The Porsche GT3's are easy prey and so are the new Z06's in the corners, they can't apply the power down as easily as a T1 equipped car in the turns at Hockenheim, it is crazy, I have vids of the new Z wiping out in a spin everytime I caught him in the turns. With the DRM coolers you can sustain high speeds and higher RPM's (think about the springs for a second) and keep the car cooler, they work real well and are an advantage at the race track, especially when you are road racing.

Sponsorsship from Movit, Pennigers Autobody and Tire Koth.

So tell me more about racing and my practical experience to make recommendations.

Ciao,
Californiakid

Bounty

I think the problem here is one of application and definition rather than knowledge or experience. To us here in the United States the term "racing" as used on this forum would generally be construed as street racing or weekend drag strip duty or occasional HPDE's...not dedicated race courses like Hockenheim, Nurburgring, etc or a dedicated race vehicle.

When offering advice to a poster I always try to carefully read the facts of where he lives, what he wants to acheive, and how much he can spend so I can offer the best possible solution. If the gentlemen is looking to stay with LS1 heads and go with a "stealth" cam he's obviously not trying to get every last drop of horsepower to run around test tracks in Germany.

As you yourself admit, LPE (the camshaft manufacturer) recommends the ZO6 springs for this poster's intended application. I personally would recommend the 918's for added security and peace of mind but there's no need for this combo to require valvespring changes every 10,000 miles.

I can appreciate your extensive experience with corporate-sponsored European road course racing and am sure if that was his goal you'd be the ideal person to turn to in that regard. Happy motoring...

californiakid

Its all cool man.

I am actually from San Jose, California, just doing time with Uncle Sam right now and enjoying what we all have in common, driving our vette and getting some sponsors while I do it.

This is a great place to get a lot of information and I do get a lot information from people who know a lot more then me. Most of the time I can search and surf here and find it, but sometimes you just have to ask.

Our club does get a chance every year to participate in Lemans so that is an event that is a must here.
Ciao,
Californiakid

See you in the fast lane.

Bounty

Definitely the forum is great for the vastness of information and extensive resources found here. Like I said, it sounds like you definitely know your **** when it comes to road racing and I bet it's a blast with the properly built car.

Thanks for your service to your country, by the way, as a former Navy corpsman I can appreciate the tough job you do!

rickhimar

Since we are on the subject of valve springs, can anyone give me their opinion on the PSI springs versus Comp or PAC springs? Planning on using either the hotcam or LPE GTE 2-3 cam with 243 stock heads on LS1.

Greg_E

Between the two cams, I would say go with the GT2-3 with upgraded springs. At idle, you can't even tell you have larger cam, and you will get better performance than the stock LS6 cam.
I have similar mods on my '99 FRC and with the LPE cam and GMPP LS6 CNC'd heads it made 403HP/386TQ. Those numbers were with Blackwing, stock LS6 intake manifold, LPE (B&B) LT headers and stock cats.
With the 853 ported heads and A4 you will probably be a little lower than those numbers but it should give you a pretty good idea where you will be.

Bholifield4901

I have a 2000 6spd FRc with goodies coming in tomorrow. I also am going with the GT2-3 cam. The price for the cam alone is $386, with the cam and the springs LPE has in a kit together is $440. Not too much for the springs, so I bought the kit. From what I am told from a friend who is a tech at chevy it will cost about $150 for a professional shop to install the springs. I'm adding a vararam intake, LS6 intake manifold, GT2-3 cam and LG street headers all at one time. Im hoping for it to seem like a completely new car when I get it back.

typeav

You have to be crazy to believe that, just to install the vararam is $500 anywhere chevy or performance shop. The springs is another $500+, the cam is in between $1000-$1500 and for the headers is another $500, I have done enough work with performance shop and chevy dealers to come out with this conclusion. Almost everybody's rate is around $100 by hour to start working on your vette. Do the math

vettenuts

PSI are excellent springs. Have used them twice in the past.

CalvinMD

Id love to hear from somebody who with an LS1 has actually DROVE their car using both these cam..preferably an A4 car and tell me if they truly think the performance diff of the LPE on the street over the Z06 cam was worth the extra money...lets face it a new LPE is much more $$$ than a new GM cam and tons more than a low mile slightly used take-out bump stick...my car is a 2000 Z28 SS and I want an extra litl kick in the pants with just a lil more nasty exhaust note...hope someone has actual experience doing just this very swap

Fastbird

The GT2-3 will sound more aggressive than the ZO6 cam. To my knowledge it's got more aggressive ramp rates which help bump it's power/torque. Is it worth the cost over a ZO6 take out cam or something? That's up to you. Makes great power though, especially on my twin turbo setup.

This was the car at 760 RWHP before the LG Turbo's and Fast manifold among other things. The turbo setup tames it down some you can hear just a little burble coming from it and more than you would a ZO6.

Photobucket is messing up for some reason. Here's a directly link to the vid:

http://vid72.photobucket.com/albums/...e/MOV00038.mp4