Jaybird29

I have to get my heads fixed for valve issue and plan on port work. Not sure If I should leave camshaft alone or upgrade? Anyone port their heads and just tune based on porting with no other mods?

MTPZ06

I know there are plenty of guys on here who have done nothing more than a CAI and some mild port/mill work, along with a tune to complete their "fix" of the heads. I've also seen guys do every supporting mod (H/C/I/LT's/TB) and retain the stock cam.

There's no right or wrong way to do it...it all depends on what you want out of the car. Stock power levels good, or go for max HP, or something in between. Street-able and reliable, full blown race car with some sacrifices on the street, or again...something in between. I would just say be honest with yourself and what your present and future goals are for the car. Plenty of people wish they had done something "while they were in there", and others find out what it means to go "too far" and wish they had left well enough alone.

BigVette427

I ended up having Kohle perform his high-velocity street porting when I ordered a core set of heads from AHP not too long ago, and I'm sticking with the OE LS7 cam. Moldstar 90 guides, Ferrea F2042p exhaust valves, and PSI 1511 valve springs. I'm going to do a full custom tune while I'm all into everything and figured a custom tune would pick up all the increased flows at all RPM's. I also reasoned that theoretically, the heads would be done if someone after me really wanted to swap cams, while they would have to pull the heads again, they would already be done.

The cylinder heads (intake flows in particular) are actually the beauty of the LS7 and I figured I may as well get them to flow as well as they can while I was swapping them out and going through all the trouble. Can't wait to get it all together and compare the dyno pulls between OE stock and the new heads.

0FrankensteinE.D.

Jaybird29,


It all comes down to what YOU want out of your Z06. With that being said are you trying to make all the power in the world, a milder heads cam intake build, or just have a great handling car with the factory bugs worked out?


Richard Doggins has made 490whp with heads only from us, while Matt K made 613whp through us with Heads/Cam/Ported MSD intake. The options are endless!


Richards heads only c6 Z.


Matt K's c6 Z.


-Russ

MTPZ06

Where did you finally land on your choice of retainers...Ti?

VPcabs

My 06 currently has ported heads, fast 102, NWTB, haltech and is on the stock cam. Makes 507 to the wheels.

BigVette427

Yes. With the 1511's I just went with the PSI Ti retainers that Kohle suggests and routinely uses with those springs.

Jaybird29

I am looking for mild to moderate performance increase but keep reliability/drivability as stock. It makes sense to me to port heads especially exhaust fixing known issue. My plan is minimum: port heads, replace valve beehive springs with dual spring, rocker trunion upgrade & tune. Still deciding on whether to replace cam as I am not looking for maximum HP for track use.

Macattack

Had mine done in 2012, no cam but did port work on top of LT headers, CAI, TB got around 500rwhp. This year I threw in a BTR cam stage 2 with a MSD, added 50rwhp and it drives amazingly well with a conservative tune. I was concerned about drivability in 12', if I knew now how nice it drives/sounds I would have done it in 2012 but no regrets kinda nice to have an added improvement 5yrs later to make the car more interesting. Good luck- you really can't go wrong unless you get over aggressive cam with a bad tune.

BigVette427

Nothing wrong with beehive valve springs, either. Katech did some spintron testing with a handful of scenarios and proven beehives stability.

How to Maintain Valvetrain Stability - LS7 Exhaust Valves
http://www.superchevy.com/how-to/140...xhaust-valves/

You want added durability, move up to the PSI 1511 valve springs. PSI is essentially the performance division of Peterson Spring that started back in 1996 with just one customer: Hendrick Motorsports. I look forward to resting easy on my OE LS7 cam with (additionally) ported and polished GM LS7 cylinder heads outfitted with Moldstar 90 valve guides (also used in NASCAR), PSI valve springs, and the hollow gun drilled stemmed Ferrea F2042p exhaust valves. Oh, and I also picked up a CHE LS trunion kit from Texas Speed and look forward to swapping them out, too.

There are a lot of great folks around here in the forum that do a great job on LS7 cylinder heads, you really can't go wrong with any that frequent this forum. Just depends upon what your trying to do. However for me and my goals, even if it was a tad overkill, I wanted Moldstar 90 guides and there is only one place that I know of who can offer those on the LS7 heads: American Heritage Performance.

The Spring That Revolutionized Nascar
http://www.popularmechanics.com/cars...ascar-6643778/

Ferrea Competition Plus Hollow Stem Valves

MikeOC

I'd swap out the cam while you're in there BUT if you're not sure what you want, get an extremely streetable cam. You won't regret a streetable cam and you won't feel like you wasted breaking open the heads. Then later if you want a high RPM cam with low speed trade offs you will know for sure that a streetable cam wasn't enough for you.

zx12rider

I gained 31whp and 35 ft lbs of torque just by going with AHP ported heads and tune - given this is with A&A blower (5-6 psi) and B&B PRT, but with stock cam and stock exhaust manifolds.

MTPZ06

Precisely the rebuild I went with from AHP...MS90 guides, F2042p ex valves, PSI 1511 beehives w/Ti retainers, CHE trunions, stock cam. I wanted stock driveability with better than stock reliability, and I feel that's what I have now.

Jaybird29

This is the route I am leaning toward, except using dual valve spring. I am nervous about single spring like beehive. If single spring fails...well you know what happens.

murf257

After a stealer "FU" I had Kohle polish my heads with nothing else done!

As a side note my stealer gave me a lot of lip service but NOTHING in writing!

MTPZ06

I don't believe I've ever heard of a single instance where a properly installed PSI 1511 spring failed...or even improperly installed for that matter. (I understand anything can break though) I have heard of, and have also seen plenty of dual spring failures. The trick to duals is catching it once the first spring fails, because the secondary spring wont hold up for very long...especially if driven hard, which could result in valve float.

Having said that, I believe Kohle's go-to spring upgrade for his typical package 4 heads are BTR duals; but I had requested he install the PSI 1511's. I think either is probably fine...I just like the stellar reputation that the PSI 1511 has in LS motors.

v8sten

my car with FRH heads and my friends with AI heads both made around 500 whp.

newchevyman

I had AHP ported heads, milled .020 with stock cam. With those heads, 2" ARH/3" ORX, Vararam CAI, and tune it made 503 rwhp and 483 rwtq. Made more power and torque from idle to redline. Never tracked the car but felt like it ran hard with those mods. Definitely will feel a seat of the pants difference.

Michael_D

Only you can decide on the cam part....... Rowdy camshafts come with pro's and con's.

Regarding port work, if you retain the stock camshaft, there will be very minimal gains, if any, from port work. In fact, there may be off idle and lower rpm losses in performance from port work. There are two basic reasons for port work on LS7 heads; 1) improve intake port flow for increased intake valve opening (+ .650"), 2) increase exh port flow to allow less exh duration when using an aggressive camshaft that has more intake lift and duration. Number 2 is the most important. OEM heads really need about 20 deg more exh duration (or more) than intake duration. They just don't carry power without a large split. With a killer exhaust port (from porting), you can reduce this split, which means less valve overlap, which ultimately improves drivability.

Gains you might hear about from end users who buy and install "ported" LS7 heads and retain stock camshaft, are mostly attributed to an increase in compression from milling, as well as an increase from tuning.

trogdor

i initially went cold air, headers, stage 2 WCC, and a torquer 116, nw 102 and MSD... but i got tired of setting off car alarms and had issues pulling through drive thrus and idling through parking lots... i was at 560rwhp 500rwtq... i had them put my factory exhaust and cam back and stock intake and throttle body back and im happy i did... now im at 500rwhp 450rwtq but the car cruises way better