This thread has been inspired because of YOU. Those of you that love the Corvette you drive. Those of you that have decided that a supercharger maybe awesome in its own right, but have desired the sound of a cam. That exhilarating thrust and pushing back into the seat they feel when you enter that power band. The way heads turn when you pull into that parking lot.

I don't know about you, but I certainly can't afford six grand right now. That's about the average to put one in yourself, anyway. And I have heard about many that have that power, yet have Mr C5 right at their side during a "skirmish" off the line because they can't hook up. This thread is not intending to put down supercharging or turbo charging in any way. I just don't have the money....lol.

So it begins here. It begins with the parts I have been slowly purchasing from William L. Morris Chevrolet in Simi Valley California. It begins with my 2007 C6 Z51. Atomic Orange Metallic. My first Corvette.

 

Up to this point..... I have only modified the car in this way: I converted the stock intake to the intake used on the LS7 and eventually the LS3. By the way, I am in no way an expert here. I am just learning, reading, researching....etc. I am just an average Joe, but with a Corvette. I appreciate all cars and desire to put none down. Anyway..... I realized that the stock LS2 intake is very restrictive, so through the above mentioned and friends, changed it to the above. I put on an Elite oil "catch" can. Vette Air Scoop. I purchased from Granatelli Motorsports their cat back exhaust. It really is nice you guys, nice sound and very light. Granatelli coils, wires and roller tipped rockers. Let's see, what else...... Pfadt 16 way adjustable shocks along with their sway bar bushings. And of course have had tuning to the engine and transmission. No HP numbers to give but the car is faster than a stock LS2.

My intentions with this thread:

 

There are many of you that have already done it...... Added a cam, etc. And for those of you that are thinking about doing it, I hope I can inspire you. Once again, it is because of YOU that I decided to do it. I don't know what the final outcome will be. I am sure that many of you will have your opinions, and I will listen. However, I have somewhat set my mind as to what I am going to do and will post it as I go. Those who wish to offer verbal help, please do. I have been looking forward to doing this for a long time, so please, this is supposed to be fun for me, so hopefully any criticism will be kept to a minimum.

 

I want to use LS or GM Performance Parts and stock GM parts only. I need to find a set of headers, preferably with O2 sensors, if they even make them. Haven't looked much into them as yet. It's all about money that I don't have, remember?...Lol. I would like any of your suggestions on that.

Okay..... This is what I am going to do, and I have no idea how long it will take. I may change a few things along the way, based on your suggestions, and of course.....money.
I am working with a 2007 C6 Z51. I am not going to be modifying the block at this time. Only after I blow it up......... Lord help me if I do....Lol.

I am going to put in a GM Performance Parts Stage 2 cam. It has a lift of .551 intake and .551 exhaust. However, with recommendation from GM Performance reps, I will be using LS7 springs, retainers, and rockers as they are 1.8 ratio. Thus lift will be .583 intake and exhaust. Duration is .227 intake and .239 exhaust with a lobe separation of 108 degrees.
I am changing the heads and intake manifold to LS3. I have been advised to CNC the exhaust chambers only. The LS3 intake was acquired from someone who could afford a supercharger. The heads and cam from William L. Morris along with all other needed parts as previously mentioned.

TO BE CONTINUED..........

 

Those cam specs seem a bit aggressive for a GMPP. A 108 centerline is gonna have a real tough time idling, especially with 18 degrees of overlap. Is there a reason you have to stay with GM parts? There are numerous cam choices out there that may be a better fit for your goals.

Also, are the LS7 springs rated to at least 0.600 lift? If not, I wouldn't use them.

Maybe others can chime in and back me up.

 

Cam specs can be found on page 206 in the GMPP Catalog. According to, and that is all I can go by, research, and more so the reps at GMPP whom I should be able to trust since they RR'd the cam, it will idle roughly, but should start right up and run at least though not well until tuned. And I believe they know what they are doing though they may have various backgrounds, those with street rods, early seventies vehicles, etc.

I know that many of you have already tried many things, and have been quite successful and have a proven thing going, but I wanted to try something different. Something I have not seen, or at least read about, though I am sure it is probably out there somewhere. I want to trust GMPP and General Motors and its products. I want to see what an LS2 engine will put out with LS3 heads and an intake. Someone out there must be interested.... For this small build, GM and GMPP parts only.

As far as the cam is concerned....The "hot" cam or ASA cam was not radical enough for what I wanted to try. The LS376/480 supposedly puts out 480 horsepower 475 lb.-ft. of torque from an LS3, just cam change and tuning. I have heard that "that is the east coast. They have better premium with higher octane", blah blah blah. I don't know.

The LS7 Beehive style coils are supposed to be good for lifts over .600. Again, GMPP recommended them. The LS7's rockers at 1.8 ratio will give the .583 lift.

 

Okay..... As soon as I can I will post pictures of the car. As far as the rest of the parts I will be using GMPP high performance roller lifters, new guides. GMPP high performance chain with 3 bolt sprocket, crank gear and balancer bolt. New pushrods, new tensioner and bolts. Replace all gaskets with new ones..... intake, throttle body, timing cover etc. Again, all GM.

I still need headers. Does any one have or know where I might find any used ones? How much?....etc. If new which brand is best?

TO BE CONTINUED.....

 

and your expecting this engine to pass CAFE standards and CA inspections?

the ASA cam does not look like much on paper, but a sealed ASA LS6 race engine will blow the doors off most LS7s and almost all LS3s

 

On the east coast you typically see 87 89 and 93 octane. Some crappy gas stations will stock 91 instead of 93, but Im not sure why (cost to them?).

Anyway, you can use specific chemicals to raise your octane. Toluene and Xylene will both work. Toluene is harder to find pure, but you can buy Xylene from lowes in 1 gallon cans.

BTW youre not the only one who wants to keep to GM parts. knowing you can destroy the car (or your kids/ grand kids can) in 2030 and still be able to find the parts to make the car exactly as it was is a nice feeling.

 

What's a "sealed" ASA LS6 race engine?

 

ASA Stock Car Engine.
American Speed Association

Here is an engine example http://www.schwankeshortblocks.com/s...?i=1554&c=1084

http://en.wikipedia.org/wiki/American_Speed_Association

video
http://www.youtube.com/watch?v=aj1PdP_F7cY

More race engines
http://www.schwankeshortblocks.com/shopping/?ic=1084

 

The OP forgot to mention the vehicle is for off road use only and those standards and inspections don't apply.

The only way you're ls6 would blow the doors off a LS7 is if they left the doors open.

 

Blow the doors off? not really but you may be surprised what driver skill will do.



if it is for off road use then get a better then a GM cam

 

You better double check on the ls7 rockers. I think the geometry is different.

 

Since you are in Ca. I would get a Z06 exhaust and mate it to your current mufflers and have a cam spec'ed for it. With a lobe separation of 108* it will idle rough and be difficult to tune with a MAF. The ASA guys don't care about idle quality, and they use Speed Density tuning, this works better than MAFs for lumpy cams due to reversion.

The VDO of the ASA race are the wrong cars.

Use the C5R timing chain from Katech or a double roller.

ARP balancer bolt. Beats the hell out of the factory torque to yield during install and can be reused.

Shave the heads to retain your compression. Look into SLP for the heads already done or buy local from someone like RPM or WCCH, both venders here.

LG, SW,ARH and Kooks all make headers and are venders here.

 

Good advice for the OP, keep it coming.

 

They are different in the fact that they have a 1.8 ratio, and that is what will give me the lift of .583. Their design is slightly different in that you can see that they are capable of much higher stress. The LS7 intake rocker is offset. The LS3 offset rocker design was taken from the LS7 also. GMPP recommended them and on this build I put my full trust in the suggestion from them.

 

I am going to use long tube headers with o2 bungs and extensions. The brand that "reads" best to me are sold by C5racer.com. I will continue to research them but at the moment I don't remember the brand. They have cats and are thermal coated with 1 7/8 primaries, o2 bungs with extension connectors, X-pipe and plug wires. I really don't need the wires.

When I was referring to "ASA", I was referring to a cam designed by GMPP. The cam gear is a new 3 hole from GMPP as is the high performance chain. I have not heard or read of any modified LS engine breaking this set up.

I will be using LS3 heads with what is being termed as "stage 3" CNC porting to the exhaust ports only. I am going to use only GMPP and GM parts. The headers will obviously not be. The Intake manifold is from a 2008 C6 that was to be supercharged.

As to shaving the heads, can you explain to me why? I do understand what you mean, but, if you read the beginning of this thread, I am using my stock LS2 block. The compression is rated at 10.9:1. The LS3 block, though stronger, is rated at 10.7:1. The combustion chambers of my previous LS2 heads were 65cc. The LS3 heads combustion chambers are 68cc. Won't it actually calculate to a wash? Or, perhaps my ending up being slightly ahead? I'm not completely sure of the answer.

Thank you for your comments. I do want to purchase headers. So, whomever has some for sale, feel free to advise. I must have them to accomplish what I hope for. I might also be interested in anyone who has a great set of used headers. Preferably a complete set from header to cat with o2 bungs and x-pipe.

I thank all of you......

 

They are different in the fact that they have a 1.8 ratio, and that is what will give me the lift of .583. Their design is slightly different in that you can see that they are capable of much higher stress. The LS7 intake rocker is offset. The LS3 offset rocker design was taken from the LS7 also. GMPP recommended them and on this build I put my full trust in the suggestion from them.

 

Son, I think your math is a little mixed up.
3 more cc's in the chambers will lower your CR, like the LS3 is.
The smaller piston diameter in the LS2 will also lower your CR.
If you call LOSE, LOSE a wash, I guess it's your motor.
Also that cam you're going to be running is going to stumble a bit on the low end. Now you've got LOSE, LOSE, LOSE.

Shaving the heads is a good idea, get your CR back to 10.9 or 11.0:1

Now you have to be careful about the valve to piston clearance, you did say you're doing it yourself?

This issue of the simple math problem in your head configuration lends me to believe you might be getting in over your head.

Just be CAREFUL friend.
In my business it's 'measure twice, cut once'

Just my $.02