I am a relatively new vette owner. I've had my '99 C5 since Nov 2005. I love the car. I previously had a 69 and a 74 vette in my younger days, but their engines were definitely old school. I have installed the following mods on my '99 since 05: 1) vortex ram air box, 2) vortex power duct, 3) SuperMaxx header exhaust system w/ free flows and X pipe, 4) LS6 intake, 5) P&P throttle body, and 6) Borla Stingers. Thanks to MTI racing's dyno tune I'm running 340RWHP and 360RWTQ. I plan on putting in new timing chains, oil pump, water pump, Z06 injectors, 224/228 cam w 570 to 575 lift (I haven't decided which vendor to buy from yet, but that's close to what I want). Now to the question . . . I have a chance to buy some LS6 heads from a reputable company; however, I'm unsure if the intake runners are too large and I need some advice from the experts. The specs on the heads are:

P&P HEADS
REV 2.020 INT VALVES 1.570 EXH VALVES REV
SPRINGS GOOD TO .600 LIFT
230 CC INT RUNNER 60 CC COMB CHAMBER
METAL CLAD VALVE SEALS
REV TIT. RETAINERS
MANLEY VALVE LOCKS
RACE VALVE JOB
SURFACED & CCD

My question is: Will this be too much for my engine? Will loose a lot of bottom end? I learned the hard way when I installed the LS6 intake with my setup. Basically, the LS6 didn't do any good due to my stock LS1 heads . . . matter of fact, I lost some bottom end till I got my car over to MTI racing for a dynotune. Pls feel free to let me know what you think? THANKS . . . undecided.
Mike C sends

 

If it were my car I would go with a Cam such as 224/228 113LSA and around .590 lift. That combined with the LS6 heads should give over 400 RWHP.

 

TSAB,
Do you think I will lose any bottom end with the size of the intake runners? I like your cam specs . . . if it weren't for my wife taking rides on the weekend with me, I would definitely go with a little more thump. Unfortunately, I will probably end up sticking with the milder cam with a 114 LSA or higher sleeper cam. Thanks for the advice.
Mike C sends

 

Pls see above discussion . . . trying to see if the 230CC intake runners are too much for a mildly modified LS1. Any other advice. Thanks.
Mike C sends

 

I ran the set up with the LS6 intake with the cam spec's I gave you. I really didn't give up much low end if any. Idle was a little rougher than stock but nothing outrageous. Fuel mileage was still around 30 mpg hwy. A little thump is a good thing.

 

Thanks TSAB . . . super nice-looking vette. Well, I guess I will go for the Wergner LS6 heads . . . I just looked up the specs on a normal Z06 head and they are at the 230CC size. I'm guessing the intake runner not to be that big of deal. Again, thanks for the info.
Mike C sends