nikleondis

I got a 2012 grandsport I'm looking to do cam/headers on. I've talked to a few speed shops3 and they said the stock heads r good up to 600whp and the power gained is from the cam. I'm looking to be 575 ish whp.
parts are
-brian tooley ls3 229/244 cam
-660" platinum spring kit with to titanium retainers (stock guides)
-pfadt 1 3/4 headers
-halltech super bee intake
-tune by Jannett racing.

I'm hoping stock clutch with hold up for weekend driving/some high ways pulls. If not I'll throw the rxt clutch in it.

Do I really need to re do the heads?

Speedforhire

I hate to be the bearer of bad news, but your current parts list will only net you about 475rwhp (+/-). If you add ported heads you can get close to 500rwhp. I don't think there's an LS3 out there that is getting 575rwhp from a N/A setup only. You will need boost to get there..........or spray. LOL!

nikleondis

Yeah that was a typo. Ment 475

nikleondis

I'm just wanting to know is the stock heads will be sufficient for this build

hungryhippo

475 is definitely realistic. Milling the heads should give you another 10hp and better midrange, but you might have to flycut the pistons. Then if the heads are off you might want to get them ported as well. Decide what you want and do it all at once.

Speedforhire

...........

nikleondis

Good to know, appreciate the info

Joe_G

I wouldn't touch the heads nor the intake. Save your money. Cam, headers and popping the shroud and you'll be making your HP goal.

Here's my friend JustinJor (now Juic3d on the forum, but not when this run was made), cam only, after he spent some time learning the Driver mod. Stock clutch following the Ranger fluid method.

www.rangeracceleration.com

He has some threads on his cam only ls3 build if you'd care to search for them, he learned a lot in the process.

tennblkc6

damn...that's haulin the mail

petsur

I got 469 RWHP with a similar build but smaller cam. Real happy with the low end as well as the entire RPM range.

dev1360

Gotta go with him on this one. The right cam in an LS3 will get you at, or slightly over 500whp with stock heads.

The stock heads are already borderline too large for the cubes. Porting them takes from the average and adds to the top. Average numbers>peak for a street car. Milling them is an option, but not worth the added cost when you're just wanting to do a cam swap.

JUIC3D

Thanks for pointing me to this thread Joe.

Stock LS3 heads are some of the best GM ever created. They took what they learned on the early LS7 heads (thankfully the valve guide issue didn't follow) and applied it to the LS3 so you're already 1 step ahead of the game to make big power n/a.

My car made 517whp with a cam and bolt-ons. The heads were factory untouched aside from the valvesprings I installed for the cam.

I had a pretty beefy cam which made driveability in parking lots and such a little more of a chore. Knowing what I know now, unless you want bragging rights of "cam only" then I would go a smidge smaller on the cam and leave yourself enough piston to valve clearance to mill the heads .030 for some added compression ratio and quench. You'll still have ~500whp or more but you would retain slightly better manners when the rpms are < 1600 which will make the driving experience (assuming you're a manual trans) much more enjoyable.

Just my $.02.. good luck!

Joe_G

^^^ Justin that is sound advice.

How does his cam in the first post compare to yours?

JUIC3D

Mine was a motorboat cam (literally for a motorboat)

230/238 .600/615 113+2 spec'd by Pat Guerra.

Without knowing the lift and LSA it's hard to compare. Mine had right at .080 PTV @ TDC which was close enough for me.

Here's the dyno and cam card

Joe_G

^^^ Justin his cam is a LOT bigger than yours. That thing is a hog.

OP you'd do well to chat with Spinmonster on this, he has no axe to grind, isn't selling anything, and did some testing with bigger vs smaller cams in the ls3. I'll see if I can roust him from his teaching career to chime in.

Speedforhire

Yes!

..........and if I may offer some advice? GO BIG or GO HOME!

Choose the cam that you think you want and then go one step bigger. Once you get it all together and tuned for the street you may find yourself somewhat disappointed.

I know I am with my build. Don't sell yourself short.

dev1360

I have a PatG 230/238 .629/.629 112+3 on CamMotion core and lobes. It's weird having such a similar cam but different driving experiences. I daily my car all day at 900-1200 cruising RPMs without bucking or surging. There are instances where I get some light surging, but nothing major at all for a 10* overlap cam.

10* of overlap is my cutoff. I wouldn't want to drive anything bigger.

JUIC3D

I forget what lobes my cam had. Keep in mind this was about 3 years ago so perhaps it's an outdated cam. The car was a runner and performed very well for the relatively small amount of mods. Driveability is a very subjective topic my nature anyhow so what I considered annoying, might be perfect for you. It all just depends.

I just think with a slightly smaller cam and some milled heads the car might have made 525-530whp which would have been very impressive. It was also the first car I really tuned so there was likely some left on the table. I've learned a lot since then.

Joe_G

There's an understatement. Post a pic of your current whip launching....lol

JUIC3D

Lol I think if I did, I'd get banned. I don't think fords are allowed to be posted here...