sampaschal

I have read several post regarding the benefits associated with doing a ZR1 cam swap in the LS3. I presumed, because of the nature of the swap, this was being done in 6spd manual cars....

I gotta know, can this be done in a 6spd automatic..will the transmission accept the added hp/torque...torque converter swap???....can the shift points be worked to use the cam's potential..just asking at the point...

any idea of cost...for a complete swap?

Mez

There is a thread I started a couple of weeks ago about a friend that did this cam swap. The reason this cam was selected was it is from GM, it was used in the ZR1, a A&A supercharger kit would be installed right away, and it was cheap.

This cam is best suited for an engine with a supercharger. You can look it up, but I recalled it made about 24 rwhp more than stock after tuning. Because of the very wide LSA, it has as much or more low rpm torque, so it is fine for the automatic transmission.

TLTONEY

old motorhead

My experience with wide LSA's is totally opposite. Wide LSA's do tend to smooth things out, but favor the upper RPM band at the expense of the low end. A cam with those same LS9 specs, with a narrower LSA (LS7 cam), is going to be better with an auto tranny. LS7 cam will cost a few bucks more unless you find one pre-owned.

Mez

You are right.

What I should have said, the LSA makes for a smooth idle due to reduced overlap. I think the LS9 cam has something like a -22 overlap. That's about the most negative I ever seen.

The wider LSA makes for less overlap with cams having identical duration. If I were going to choose between the LS7 and LS9 cam for a NA car, I would get the LS7.

sampaschal

Part numbers please...track down someone that has done this...I like to think I am a pioneer, but would like to have someone that can talk details. Cams with greater lobe separation tend to kill low end torque but make horespower in the upper range of the power band...that said, you usually need to upgrade the valve train components to survive. Heads have to breath and upgrade exhaust usually comes with the package...to reach the potential of the head improvements...Can it be done at some reasonable price?

tomiboy

Sam, keep in mind you won't get the valve lift like a Z06 because the Z has 1.8 rockers and the LS3 has 1.7

JoesC5

Very true, but the aftermarket has 1.8 rocker arms for the LS3.

old motorhead

Then you need springs. The LS9 cam loses its appeal when you have to add springs. To me, it has value as an inexpensive upgrade if you're not expecting much and can use the stock springs. When you have to go to all the trouble of a spring swap with aftermarket rockers, you might as well spec a cam that will fit what you're trying to do. No need for aftermarket rocker arms that way.

JoesC5

Will the stock LS7 #12578457 valves springs @ $5.87 ea, work?

Loaded08

The 1.8 rockers themselves are probably 5X the price of the cam. But looking at summit, it looks like the LS7 rockers aren't any different.

The SLP units are $650.

gunterwalker

The ZR1 cam is ok and I agree with all you guys have said but I think it is really a waste of time and $$$ to install that cam. If you are going to do a cam swap get some power out of it and dont waste your time with that cam unless you have a blower.

0Brian@RPT

All that is needed for the swap is the cam, 3 bolt cam gear, cam gear bolts, balancer bolt and any gaskets you find that need replaced. The stock springs can handle the LS9 cam since the same springs that are installed on the ZR1.

This cam will not be for everybody. What the cam provides is more gains than headers and idles, sounds and drives like stock. I have had the cam installed in my 08 Vette and it was what I was loking for. Plus, the ramp rates are not valvespring breakers and do not need replaced. There are gains from this cam, just not as much as aftermarket cams.

With that said, if you want to take a step further get the LS7 manifolds and H-Pipe. With the LS9 cam and LS7 Exhaust, I gained 51 rwhp over stock. Can't even tell I did anything to the car. The exhaust was $350 shipped and the cam was $126

Loaded08

Did you tune the car to realize those gains? My guess would be yes. I already have the LS7 manifolds and I'm totally with you on the "bang for the buck" ~500 bucks for 51HP is insane cheap with a C6 corvette.

sampaschal

Now we are making some sense from this...amount of investment...and return on investment...increased HP for $$ invested. Cam is worth X$$$ ... the manifolds...X$$$ and aftermarket exhaust up grade...X$$$ with some return in RWHP....now you can assess value. I agree 51 RWHP for about $500.00 and some cost for a tune....that ain't too bad. The car's valve train in not stressed...streetability may actually improve....and no loss of efficiency...Now can someone please include part # and sourcess...that would be nice...

sampaschal

The higher ratio rockers on the Z06 will provide a nominal increase in lift over the lower ratio LS3s...that said...does it warrant moving to the Z06 rockers given that springs and other valve train components can stand up to the higher lift??

Loaded08

I think they are the same rockers. They are one of those parts where GM updates parts for multiple engines. Someone please, keep me honest, but I think they're the same. (What may have been two part #s originally is now a single part)

Edit: Google part number 10214664 (exh) and 12569167 (intake)

RLSebring

^^^^^
I basically went the same route. I pulled the HOT CAM out and installed an LS7 cam retaining the stock springs and rockers. For 2 years I could not stand the erratic, to say the least, behavior of the idle and slow speed drivibility with the Hot Cam.

The LS7 satisfied me to a "T". Stock idle and about the same Torque feel that I had with the HC. Drivibility is a dream now. Although I'm not a barn burner it gave me what I was looking for and for cheap.

old motorhead

LS7's have 1.8 ratio arms. All other LS engines use 1.7 arms. LS3 intakes use offset intake arms similar to the LS7 intakes, but the ratio is different. From what I understand the LS7 rockers are not usable on other LS engines.