masoch

I've been doing a lot of research about how to go forward with a cam installation on my '09 Z06. It has full exhaust, halltech, ferrea valves/upgraded guides and tune already. I've got some questions I'd like answered by people more knowledgeable than me in the LS7 world(which is just about everyone here).

I think I've decided to go with the LPE GT19 cam, as the car is almost a daily driver street manners are important. Would this cam's higher than usual lift be an issue with stock rockers? Everything I've read suggests that it should be fine but I can't help but think it might be a bit much. I don't want this cam eating up the valvetrain. I'm open to any additional suggestions in the cam department; I really want a cam that is going to strike a nice balance between power and reliability.

I'm also wondering if I should do an intake manifold at the same time. From what I can tell my choices are basically the FAST or the MSD intakes. My question here is what is needed to compliment an intake manifold installation; will the fuel rails fit? Do I absolutely need a new throttle body? If a TB isn't needed, how much power would I be leaving on the table by not doing it now?

I've also been told that a trunion upgrade with the cam would be a good idea. However after some searching on the forum I've found some differing schools of thought about whether or not it's worth doing. I'd really like to hear some more opinions on that as well.

Unreal

Stock trunions are fine.

Lifters, pushrods, good studs/bolts.

masoch

On the subject of lifters. Which would you recommend and why?

Unreal

Johnsons

Because they work and are a nice upgrade. Morels are nice too if you want to spend $500+

Drew03tx

As unreal said I think the stock trunions are fine. I'm about to have a bigger cam installed from a reputatable vendor on the forums and he told me to save my money on upgrading the trunions, just buy oem rocker arm replacements if it's a must.

masoch

Thank you both for the opinions. The car has just under 8k miles of fairly easy driving so I'm thinking that the rockers are probably fine. I'm definitely going to be looking into lifter replacement. Can lifters be installed without head removal? Excuse my lack of knowledge here.

Unreal

No, lifters cannot be installed without head removal, but you should never do a cam without doing heads, so not really an issue.

Mordeth

I currently run the GT19 cam. Generates a metric **** ton of power and torque under the curve with great driveability. Good lope, sounds wicked, only a little surge and runs like a bat out of hell in a racing environment. However, due to the high lift and aggressive lobes, it puts a serious beating on the valve train if raced. Plan for regular checks on the entire valve train if you run this cam. I pull my heads a few times a year for refreshing so it doesn't bother me much. It likely would bother most other people.

If you are just tooling around town or blasting up expressway ramps, it is a nice cam. But if you race it or beat on it, like I do mine, prepare to chew through guides, rockers, springs, lifters and valves. My dual Ferrera springs were hosed after about 500 track miles. Same with my already repaired heads. I tossed in some Moldstar 90 guides and PAC1209X springs just so I could finish the season without completely tearing into the motor.

Over the winter I'll be pulling the motor, forging the bottom end, refreshing the whole operation and likely ditching this cam.

As for your other questions:

Go with a Mamo ported MSD for the intake manifold. Nevermind the FAST. Mamo MSD is worth 25-30hp and even more torque across the whole RPM band. Fuel rail will transfer over with no modifications.

For another 3-5 hp go with a Nick Williams 102mm throttle body. Mates well with the MSD.
​​​​​​
Stick with stock rockers and stock lifters (if they pass an inspection). There is no reason to spend money here. None WHATSOEVER. They work perfectly fine for your application. If the heads aren't coming off then just inspect rockers and springs and wiggle the valves for piece of mind.

Do you have a CAI? If not, might as well toss on a Halltech 103 or 108 for another 10-15hp.

As for an alternative cam, contact Kip at Cam Motion, Texas Speed or Pat Guerra for a custom grind. Don't take advice on cam selection for your car/application from random people on the internet, and don't just buy an off the shelf grind because someone else did.

Unreal

And agreed, for a mild setup, I would just run stock lifters, but if you want to spend money, it isn't a horrible place, but definately not needed.

MTPZ06

Too much lift for a daily driver with too aggressive of a lobe design IMO; and as Mordeth said, be prepared to do periodic maintenance on your valvetrain. Can you run this cam with good results...sure, but you see what Mordeth has to contend with.

My recommendation...keep your lift under .635", as the stock rockers move outside the range of an ideal wipe pattern beyond that; which causes side loading and over time that will cause excess guide wear in an hourglass shape. Roller rockers can alleviate this, but there's no good options for those short of a very expensive shaft mount system that requires machining the rocker pedestals on your OE head castings. YellaTerra makes bolt on roller rockers (mini shaft design), but I'm not a big fan of those with an aggressive cam, or really anything other than stock...just a personal preference here.

As for intakes...Mamo MSD hands down.

Contact Kip at Cam Motion...they offer much better lobe designs that are less taxing on your valvtrain and will exhibit excellent drivability.

racerx3317

How hard is a cam swap for a DIY? I wanna do a BTR stage 3 when I do my heads. I'm thinking of doing it myself. Never done a cam before.

Unreal

For some people swapping tires is hard.

So no way to answer that. Read a guide, and see if it is something you want to do. Nothing hard about it, just takes a day.

racerx3317

Lol, maybe I should have been more specific. Reasonably experienced and very mechanically inclined. I rarely go to a mechanic for any reason. Haven't done much work on Corvettes and never did a cam. Just wondering if there was anything vette specific I should know.

Mordeth

Cam swap is a bit of work. Takes me a solid full day or a lazy weekend. Unreal could probably do it faster. Vette specific? Well you will either need to drop the cradle or remove the steering rack. Your choice. I drop the cradle as dealing with reinstalling the steering rack is a major pain in the ***. And the oil pan doesn't need to be dropped to get to the oil pump, but I loosen a few bolts to get it back on. Make sure to mark your balancer.

Bag and tag everything. Take pictures.

81turbota

TB isn't needed but it will help with driveability a little. My car has a CMS stage 4 cam, it put 575rwhp on a Mustang dyno with a stock TB. The car drives like a big cam car (I'm an old carbureted guy at heart) and has a few cold start issues (like 1 in 25 starts). It's barely noticeable, it doesn't bother me and CMS said don't bother with the 102 TB. They said it would help the cold driveability but it would only be worth 2-3 rwhp on my setup.

Also, I didn't see you mention a clutch. You'll be playing with fire on a stock clutch.

Many people suggest a reduced maintenance interval for your heads based on how aggressive your cam is. BTR stage 4 guys have been talking 20k spring/guide inspection intervals. It makes sense, these are pushing over .600" lift. Do that in a Gen 1 small block and I would be checking springs at 10k or less. I emailed CMS about their recommended maintenance interval for their cam profile, I will find out soon. Their cams are made by CamMotion.

Unreal

Dropping the rack is the only crappy part. Other than that, it is simple bolt on/bolt off stuff.

Any big cam, or aftermarket valve train should get 20k inspection/maintenance. That is just part of owning a big lift cam.

Buddy A

Like others have stated the rack is the biggest PITA. Removal isn't as bad as reinstalling it. Power steering is another PITA. 1/32nd of a revoluion at a time to remove a couple bolts. Rest is pretty straight forward. Move condenser up and slide cam out. No need to touch refrigerant.

BigVette427

Don't you need an alignment if you drop your steering rack? Also, suggest that you ditch the OE GM balancer (look it up on C5's and other C6's that need it replaced) Consider a PowerBond Race Series PB1503SS - it's far and away superior to the OE balancer and can be had for under $300. Dynamically balanced. You can always spend more ATI and others.

Unreal

Alignment isn't a bad idea, but most don't. Then again, most corvettes are no where near aligned properly.

Mordeth

As I mentioned earlier, just drop the cradle and don't screw around with the rack. 6" will do it and give you enough room to get the balancer over the rack. As for a balancer, IW makes the best one - period.