I want to install a maggie next year sometime. Would it be better to install a set of 2004 Z06 heads now (which I hve access to)or have my 2000 LS1 heads worked on? Which cam should I install with the heads given the intent to put on the maggie at a later date? Looking for a little rump rump in the idle or should I just wait, install the maggie and leave the valvetrain alone? I already have done the LTH Hi flo cats and Corsa Pace car stuff along with a ported TB and Blackwing and dyno tune.The car is just a street stomper and probably will not go to the dragstrip except for a couple of passes for bragging rights. Am I making any sense here?

 

If it helps, the LS6 motors seems to make about 50 more RWHP than the LS1 motors with a maggie with the same boost. So if you can get some LS6 heads at a resonable price, then I would say go for it. The LS6 cam seems to be a good cam too for a Maggie. But there is others. You have to pin the crank pulley, so it's a good time to change the cam, oil pump, and timing chain.

 

The very thing that gives you lope (rump, rump,) is overlap, and overlap will hurt you on a blower cam. I'm not saying it won't work, but you will get more power out of a cam with less overlap (larger LSA.)

 

Your stock LS1 heads have 66.5cc chambers giving you 10.1 compression while the stock LS6 heads have 64cc chambers which would bump your compression to 10.5.1. The lower 10.1 compression would be better for a boosted application, although I would see nothing wrong with running the LS6 heads on there. I would suggest having your stock heads cleaned up a bit, possibly ported & polished, and not mill them any to retain the lower compression ratio. If you know you want to run with a lot of boost then I would suggest the 6.0L LQ9 317 heads, they have 72cc chambers and will lower your compression close to 9.1...from what I recall. However, from what you posted I believe you will be happy with the P&P stock heads, with a blower specific cam, and the stock out of the box Maggie...

As far as a cam I would suggest a proven blower grind from LGMotorsports, East Coast Superchargers(ECS), or A&A. Some in the low 220's is a good blower grind...220/224 or 224/228...Hope this Helps.

 

Ok, this all makes sense but why change the oil pump if it is not broke?

 

So as I understand your sugestions: P&P my heads and install a blower cam now, then when I get the maggie I will be good togo? What about rockers and springs?

 

Because you are already there, and oil pumps are cheap, compared to the time / labor to replace it.

 

DO NOT, use the LQ9 heads. You will lose power. Ask me how I know this. You don't NOT need to run low compression on a Maggie. You're not going make that much boost. Now if you could get 14-16 psi of boost, then the LQ9 heads would make sense.
You will make more power with the LS6 heads. That's a fact. Just look at all the people with Z06's with maggies, and compare them to the LS1 motors. You can run less boost, and heat the air up less (which is a good thing). LS6 heads with about 6-7 psi and a LS6 cam or a GT2-3 should get your around 500 RWHP with a MN6. The LS6 cam is a great cam for F/I because it has a very wide lobe seperation angle. If you want more proof, start a thread in the F/I section asking Maggie owners to show there power and specs.

 

Now that makes sense. I understood about the timing chain, I just was wondering why to change the oil pump.Should I upgrade the pump, and if so to what?

 

Ok, I'm asking how do you know this. I do not want to waste money on a P&P for my LS1 heads if I can just buy some low mileage LS6 heads and freshen them up. What about the LS6 rockers and springs,leave them alone or change them?

 

I am using one from GM, I think it's for a LS4 motor. And it's only about $60-$70 from Fred Beans I believe. It gives be between 60-70 psi of oil pressure. I have heard someone from SDPC saying it can suck the pain dry. But I have never had that problem. And I know others on LS1tech that has been running it with no problems of that.

 

I know this because I have a set on my car now. And at 10 psi, I am only making 425 RWHP thru an A4. I did a calculation for me DCR yesterday, and it's only 7.56:1 with my GT2-3 cam. Andy at A@A told me unless I am going to run over 14psi of boost, I don't need that low of compression. So I got a set of AFR 205's coming with 66cc chambers, and a set of .040" gaskets, which should give me about 10.25:1 compression. Now I only have around 9.6:1 compression. These guys that are running the 317 LQ9 heads are the guys running higher boost. So it works great for them. The Maggies love compression.
I would defently at least put in a fresh set of springs. I have a brand new set of LS6 springs that came with my cam, and has never been taken out of the box I will sell you $60. Or, get a set of Patriot Gold Springs. That's what I have on my LQ9 heads. They are very nice springs for about $250, that has Titanium retainers, and double valve springs for a extra peice of mind from the fear of ever breaking a spring.
The stock rockers are good rockers. There has been a few people have the needle bearings come apart though. Harland and Sharp has a fix for this for around $250, they will rebuild your rockers. The stock rockers are very light. I'm running Yella Terra myself, mainly because I didn't want to wait to have mine rebuilt, and I didn't want to chance a needle bearing falure.

 

A year or so ago, I was bored and did a test using a set of LS6 Z06 (had lightweight valves and yellow springs) heads on my maggie.
Oh, BTW, YMMV

Read my post here to see what the results were.http://forums.corvetteforum.com/show...t=maggie+heads

 

That's interesting. But if you didn't retune the motor, then that may be why there wasn't much of a power increase. Of course, you wouldn't think a retune would make that much differnce. It's interesting that you was able to run the same timing. What cam was your using with it?
I know from looking at LOTS of Maggie dyno charts from people on here the last 2 years, the LS6 motors always seem to make about 50 more RWHP than the LS1 motors. And the only difference between the two is the heads and cam. But maybe they are just a good match for one another. Which is why I asked what cam you was running. Heads and cam needs to match with each other.

 

I got a set of AFR 205's coming, so it's going to be interesting to see what difference I get from the LQ9 heads. I'm going to go and do a base Dyno run on the person that will retune it, so I can have a accurate comparisson.

 

I was using a factory 99 C5 cam.

Me thinks the majority of the improvements is in the cam. From my understanding the 3 major differences engine wise between a LS1 and a LS6 are:
1) Heads
2) Cam
3) Intake

Obviously intake doesn't apply for maggie cars.

Like I said, everyone's mileage may very. BTW, my 317's (LQ9) run about the same as 853's. With the lower compression I could probably increase timing a bit, but haven't had a chance to test that theory out on the dyno.

 

Ok, what the heck is YMMV?

 

I can only get about 14 degrees of timing with my LQ9's, and even with that, I get about 2 degrees of knock retard sometimes. This is with 91 octane crap though. I am also making 10 psi of boost, which is heating the IAT up a good bit.

 

Your Milage May Very............I think.

 

The LS6 heads I am getting only have 1500 miles on them, should I still replace the springs? I like your idea of the Patrot ones with the titanium retainers. I might just go with an LS6 manifold for now unil the maggie in the future. Is my ported TB ok for this right now? I have an automatic by the way. I was also going to do the GM converter #24208645, a little higher stall speed without having to do a cooler.