xHairyBuffalo

EDIT:

First of all, I would like to thank everyone for their input. Instead of replying to everyone's comments individually, I'll post my updates here.

Coming from the FI world, it seems like the E85 gains I anticipated are not plausible with a mild cam NA LS7. Looks like 600whp is in fact, not possible with the drivability I want. However, I will still go with e85 since it is still a cheap guaranteed HP/torque boost.

I've also decided to expand my budget and include a head job (hehe) and valve alignment. And, since the motor will already be opened, have the cam set installed at the same time. So, it's looking more like a $6-7k endeavor since I'll be paying for labor. Speaking of labor costs, about how many shop hours should a head job and cam install run?

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Hello,

I recently purchased a completely stock 2007 z06, and am mapping out my mod list based on cost-per power benefit. I plan to do all installation on my own, which is where the majority of the cost cutting comes from. I also plan to cut out all exhaust modifications, since the true power benefit of headers is still debatable (and everyone knows cat-backs are just noisemakers). The car also has only 17k miles on it, and is up to snuff on all recalls. My goal with the car is to make cheap, reliable power with all motor and maximum drivability for Sunday cruising. So, here is what I came up with:

1. Hi-Flow Air Filter ($79). To be honest, the most restrictive part of the stock Z06 intake is not the intake itself, but the material in the filter. The functionality of the intake with the hood scoop should suffice for any NA motor builds.

2. Lingenfelter GT-19 cam ($386.95). Street-able, and still able to make 520whp with 93.

3. ^ Valve Springs / retainer kit for said cam ($1,175). Some say you can reuse your stock springs, but because of the next mod on my list I would rather pay the monkey now...

4. LMR Houston's e85 kit ($500). This is an interesting kit, as it is able to read your current fuel and adjust your engine parameters accordingly. So, if this works as advistised, it eliminates the need for purchasing a hand-held tuner ($500) and the hassle of having to switch tunes when you cant find e85.

5. LMR custom tune ($550 with e85). I ran e85 in my Scooby, and made roughly 20% more HP and 25% more torque (granted the scooby is FI) than what i did on 93. From what I've seen, it looks to be the same case with the ls7.

6. Head / valve alignment ($1700 quote from LMR). After additional research and comments (thanks guys), it seems like this is an inescapable mod for anyone who wants to make reliable power.

So, for a whopping total of $2611.95 $4311.95, it looks like (on paper at least) I can push 600rwhp. If you have any suggestions or advise, please let me know. Thanks!

AzDave47

Have the heads been redone so you have good alignment of valves/valve guides? If not, then that should be your first priority. Just having the heads redone is about $1300 and then add another $700 if you want special porting. There are a choice of good forum vendors that do this work.

xHairyBuffalo

No, the car literally sat in a warehouse for 8 years with occasional drives to update recalls. I agree that redoing the heads would be beneficial, but is it absolutely necessary? probably not. Although most tuners would say yes, since they can make some good labor rates from it.

RGT

You will need to mill the heads to achieve 13.5 to 1308 cr if you want to make big power with the E85 set up. Also, I think there are better cams out there if your goal is to reach 600 rwhp. Check out the cams that are offered by BTR or Vette-Air.

xHairyBuffalo

I checked out the Black Mamba, but nothing by BTR. The GT-19 seems to be one of the best options for drivability, which is why I'm, leaning towards that. As far as the BTR cams, do you have any recommendations similar in lift / overlap to the GT-19? Thanks

AzDave47

Even brand new replacement heads have had valve guide measurements taken by a skilled owner and have been out of spec. Also several forum members have reported out of spec guides with less than 4K miles on it. Your car is beyond warranty. I would not consider risking an $17K engine replacement on an out of warranty engine. Looking at doing a budget HP build, I'm guessing you don't have $17K sitting around waiting to buy a replacement engine.

xHairyBuffalo

Thanks for the input, but personal finances are not of concern. I just like being efficient in my purchasing, since modifying a car is one of the worst investments anyone can make

djfury05

I doubt the stock fuel system is even adequate for E85, never researched it though.

How is a valve spring and retainer kit $1175?!

TRSCobra

I can't imagine the stock valve guides would hold up too long with the GT19 cam's valve lift. Not with the stock rockers, at least.

The airaid intake would give more power than just an aftermarket filter, especially buying one used. And to my knowledge, nobody's ever got 600whp on the stock manifolds, either (without going with a supercharger).

xHairyBuffalo

Here is the spring and retainer kit direct from lingenfelter... http://www.lingenfelter.com/mm5/merc...2#.VUF8KCFVhBc

As far as the fuel system goes, even my tuner said the stock fuel system can handle e85 with a cam no problem

djfury05

Those springs and retainers are way over priced. I'd steer clear from the GT-19 as well there are better cams out there. BTR, PAC, or PSI springs are what I'd be looking into.

xHairyBuffalo

So it seems like redoing the heads and getting the valve guide alignment is becoming a must at this point. I'm still not sold on an intake though... I had to go aftermarket on my WRX since it had such a huge box on it. not to mention i had to run 26lbs of boost...

jitsu10

you cant get to 600 with those mods and if ya did and didnt get the heads done you would be a fool.

Josh B.

Like already mentioned, I'd repair the heads first and enjoy the endless WOT of 505hp. Then, if you still have the itch, grab a big cam and the supporting mods.

However you get to 600rwhp, the LS7 clutch will be short lived, so I would say that your $3k budget is too optimistic.

If you can do it though, once you are done, I'd be interested in reading your budget breakdown to show what can be done without spending a great deal. I was just mentioning to another Z06 friend that Texas Speed headers look like a good deal at $750, especially when you can get $300+ for your factory manifolds on ebay, I even got $40 for my LS7 cam.

xHairyBuffalo

LMR said they could do a custom comp cam kit good for a .675 lift for $1200, but would do the install which is what racks up the labor costs. I'm assuming that springs and retainer kits are specific to the specs of the cam, which is why Lingenfelter can sell a $370 cam but charge a ridiculous amount for the supporting modifications. Seems like the LMR cam kit is my best option, if I can cut down on the labor costs

djfury05

Who cares if they're specific to the cam the rest of the combo isn't. If you want to spend $1175 for some $300 springs fine, or you can expand your horizons and buy all the stuff on your own and install it yourself like you said. Plenty of sponsors on here would be more than willing to help spec a combo without having the requirement to let them install it and cost a bunch of labor. Your call good luck.

Vito.A

You must get the valve guides done. You have to remove the heads to change lifters anyway, so send the heads to either WCCH, or American Heritage.


The others are correct. $1175 for springs and retainers is way over priced. Also, those are 1.800" height LS1 springs and retainers. LS7 spring install height is 1.959". You can use LS1 springs, but it is not optimum.


Most recommend you stay under .650" lift with OEM rockers.


What is so special about 600 RWHP? What about torque curve? You can achieve 600hp peak, but what about power where you drive the car the most?
I'd rethink your goals and methods of achievement.
Best of luck!

C5 LS7

Vito A nailed it. The heads need to be addressed.

The car makes 505 hp now. Its already a rocketship. A few $$ spent on sticky tires and some driving lessons would pay huge dividends. Learning to drive the car REALLY fast on a track would be way more rewarding then another 100hp. Street tires barely can handle the power output now at 6000 rpms plus. When you can keep the throttle floored 75% of the time, you MIGHT need more HP LOL.

djfury05

If your going to spend $1700 through LMR to get new guides done and whatever else they're doing, you might as well send the heads off to WCCH or AHP etc to get a full CNC job for that money.

xHairyBuffalo

Thanks for the tips, definitely something i need to look into more.

There's really nothing special about 600rwhp, it just seemed like a good estimate for a cam and e85. As I said, my goal is drivability and inexpensive power, which is why i prefer a more mild cam.

My other car is a 480whp Subaru that doesnt hit max boost until 4.5k, so I've experienced the pain that comes with driving a dyno queen.