I have a stock 99 LS1 with 45,000 miles. I am planning to go to the Z06 Intake and a set of Kooks long tube headers with cats. I like to do a Cam and Head swap. I know the Z06 heads perform well on a all street application which is what I'm after I will never road race and maybe run down the strip once just to get a time. What after market heads would give me good all round performance like the Z06 heads? I hesitate buying used heads do to hidden cracks damage of the like or I'd buy a used set of the Z06 heads. Yes I want more performance but I don't want to kill the driveabliity and mileage. What I am looking for here is actual expirence. If you have bought aftermarket heads and cam what did you buy and why? What problems did you run into? How did your car perform did it meet or exceed your expectations? Would you do it again?

 

I just did a cam upgrade. I already have the 243 heads and am still trying to see if anything like AFR is really worth the money on the upgrade for street applications. I am unsure it is.

I got the TSP 233/239 cam on 112lsa. I had a 216/224 in the car prior. The difference in drivability to me, is not much at all between the two cams. If I were to do it all over I would go with something in the high 220's or 30's right away. There really isn't much difference in terms of drivability between the 2. My car is also a daily driver. I just did it myself and used ls1howto as a good guide. Definitely worth the upgrade!

 

Aftermarket heads will be quite a bit more expensive than a pair of ported GM heads. Either ported 5.3 or LS6 heads are a great budget choice. But I'll have to say I've been very happy with my AFR 205s, and I haven't seen anyone here locally that has matched my dyno numbers (471 whp) with their ported GM heads. It will boil down to how much you are willing to spend. The aftermarket heads will run up to $1000 more than ported GM heads so it just might not be worth the extra money for many people. I bought my AFRs used for $1,700 so it wasn't much more money compared to ported GM heads. Trickflow 215s would be another great choice.
Driveability will all depend on the ability of your tuner. After a lot of reading, trial and error, etc, I have worked out a decent tune for my car. Keep the cam selection somewhat conservative (valve overlap @ .050" under 10°), and you will end up with +100 to 150 extra hp and no problems with daily driver duty. I have logged nearly 70k miles since adding the heads/cam and only extra maintenance was to change valves spring once as a preventive measure. Only downside for me was a loss of ~ 2 mpg in my daily commute (still average 23 mpg with mixed driving) - but I would totally do it again for the extra performance. My avatar picture says it all for me - spanking an old school Mopar with my daily driver running 7.5 eighth mile...

 

Guys thanks for your responses this is the kind of information I am looking for. Not all of us are road or drag racers. Most us use our cars as drivers or weekend toys. That said we still want good performance. I have a friend with a 92 with a centrifugal supercharger at a 65 mph start he could barely pull away from my bone stock LS1. Next time that won't happen. Can anyone give what to look for in buying a set of the Z06 heads used. It seems that there must be less of a chance in getting bad heads then the old steel ones.

 

There is a lot to look at when buying heads used.
*You need to know the combustion chamber volume is in order to calculate your compression ratio and select the best head gasket thickness.
* Plan to buy new valve springs unless you are confident on the condition of the used springs.
* Plan to replace valve seals when replacing those springs
* Inspect all threaded holes to look for thread damage
* Inspect all valves for possible contact with piston
* Inspect the valve tips for uneven or excess wear from rocker arms
* Inspect the deck for damage and check with a straight edge for flatness

 

Love my AFR 205's as well. I Don't really get much time to hit the track or dragstrip, but still love how my combo performs on the street. It really is a matter of if you think the extra HP is worth it to you. Long tubes, LS6 intake, ported GM heads and a nice cam would still be a great combo. If you plan on staying NA them milling for some extra compression is pretty cost effective too.

Only problems I ran in to with my heads was that I had to notch the heads a little to get enough clearance for the back of my Yella Terra rockers. I also had Tony Mamo port my heads for me. I saw a drop in a few MPG after the swap, but nothing crazy. I went with the AFR 6016 cam which is by no means wild, so I didn't see any loss of drivability or street manners

 

This sounds like the way I think i'd like to go. I looked at the spec's for these heads and they are designed for a mild street application. They also reccomended the LS6 intake which I already have. They only way I would go with LS6 heads is if I could find a set from a trustworthy source.

 

The 5.3l TSP heads are a great budget head as they bump compression ~.75. I picked up 30rwhp over the stock ls1 with a small cam. If you want to run a big cam be sure and have them back cut the valve seats for more PTV clearance, but it doesn't sound like you're wanting anything crazy. I'd recommend something along the lines of a 224/230 XFI 113+2 for a great all around cam.