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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
If you haven't heard, LS7's are popping like flies from the rod coatings taking out the rod bearings. Add my 2007 Z06 to the list (42k miles, not abused, no track time). A few weeks ago I was cruising on the interstate with the wife and out of no where sounded like my engine let go and rods were bouncing all around. The engine stayed running but I killed it and coasted to the side of the road. I called up Joe @ Cordes Performance which is local to me and he said it sounds like the rod coatings wore off based on my description (spoiler: he was right). I drained the oil later that week, and found lots of metal flakes in the oil (see picture). So, it was time for a rebuild.
First, huge shout out to Joe@Cordes Performance, Anthony@HPR, A&A Corvette, LME, Thompson Motorsports, Unreal (Nick), and anyone else I called and spent countless hours on the phone learning from. I'm not from the LS/V8 world at all, so I had a huge learning curve though I am familiar with building other cars. I was originally going to let Cordes handle it but I didn't want to wait a couple months and ended up just diving in and will be doing everything myself (with my awesome friend's assistance). I've had a built SRT4, MK4 Supra, GTR, Viper, among others. I knew that when I was going to have to rebuild the LS7 that I wanted to not just dump the money in vain and would rather have something with more power. Previous power adder mods were really only AHP Stage 4 heads, so I basically am coming from a stock Z06. I have considered everywhere from just throwing in a used LS7 to building something upwards of 800whp.
After a few weeks of research, I have decided to go a homemade 447ci NA Build. I am aiming for a street driven setup that is fun and around 600whp on pump 91, 625whp on E54 (probably conservative numbers but happy with anything around or above that). This car will be on E54 (highest we have in AZ) most of the time but have a flex tune available for 91 octane. Budget is roughly $25k and looks to be coming in a couple grand under. I may regret doing this at home rather than going with HPR, but I have a few friends that have built a number of engines and I'm looking forward to doing everything hands on rather than a shop so I can guarantee success (or blame myself).
447ci Long Block (12:1-12.2:1 CR) - 4.125" Stroke, 4.155" Bore
Darton Sleeves
Callies Compstar Forged Rods
Callies Compstar Forged Crankshaft
Wiseco Pistons -2.8cc w/ upgraded pins
King XP Rod and Main Bearings
Durabond Cam Bearings
ARP Main Studs
C5R Timing Chain
GM LS9 Oil Pump
ARP Cam Bolts
ARP Head Studs
Cometic Headgaskets
Johnson 2110R Lifters
Cordes Performance Gamma custom billet camshaft
Powerbond Race Harmonic Balancer (OEM Size)
WCCH Stage 2 Ported Heads, 69cc
Manley Ti/Mo Intake Valves
BTR Chromoly Pushrods
Platinum BTR .685" Valve Springs w/ Ti Retainers
Performance
MSD Airforce Intake Manifold
NW 102mm Throttle Body
Airraid CAI
ARH 2" Headers w/ 3" Xpipe
Mighty Mouse Mild Catch Can
Prospeed Dual Fan Kit
DRM Valved Bilsteins
Flex Fuel Tune from NicD @ Cordes Perforance
Transmission
Monster LT1-S Twin Disc Clutch
TickShift Billet Release Bearing
Remote Bleeder Line
Fuel
60lb Bosch Injectors
DSX Flex Fuel Connector
Walbro 450 Fuel Pump in-tank
Racetronix Fuel Pump Full and Intermediate Wiring Harnesses
This past weekend we pulled the engine from the Z06. I am only working on the floor of my garage so we pulled the engine from the top. It really wasn't too bad, just a lot of learning in the process. We disconnected everything that looked important, dropped the front crossmember a tad and popped her right up.
Of course on disassembly it was confirmed the rod bearings were completely toast on the rods closer to the back of the car. The rod coatings were worn off on the last two rods which I'm sure led to metal in the oil and taking out the bearings.
Next step will be to send the block and heads to a local machine shop to have them a) install darton sleeves b) Check out the condition of my AHP Stage 4 heads c) balance my rotating assembly.
I just today made my first purchase, the rotating assembly (K1 Rods and Crank, and Wiseco Pistons with upgraded pins). The wallet will be thinning out soon enough!
Yup that is the plan, at least until I get too deep in the hole hah.
Originally Posted by Unreal
I think your making a big mistake.
Anyways, if if you need a hand or anything just give me a shout. My new motor just shipped and I've done this more times than I can count.
Still think NA is the way to go? I just kept getting hung up on the fact that I could never go for more power if I wanted more because everything would be designed around NA.
Yup that is the plan, at least until I get too deep in the hole hah.
Still think NA is the way to go? I just kept getting hung up on the fact that I could never go for more power if I wanted more because everything would be designed around NA.
Lets grab a beer and talk about it.
Yes i would go na unless it is strictly a weekend race car toy. I would change a lot of parts and add a ton more. I think that budget will be tight for a legit 750rwhp setup.
I think Unreal has been down this path before go have a beer with him. Also with your heat out there and blower you will need some prospered fans to keep it cool.
I would change at least 50% of the parts selected and add a ton more. Then again i would go na if doiing it over again. Some good stuff listed, some bad stuff, some waste of money stuff, some stuff that isnt needed and many missing items. For an actual reliable usable 750 he needs to bump the budget or just enjoy the limits of az pump 91 which would be ~650ish. Since we dont have e85 at pump and the few e54 stations are at risk not sure i would plan a ethanol based build.
Sorry about the engine failure. I recently went through the same thing, but my cam core wore down and ended up wiping my main bearings. To my surpise the rods were pristine (20k miles). Car was a H/C/I making 620whp on 93 oct for a couple years. I decied I wanted to keep it N/A and improve upon the build while its out so I decied to do a full fresh rebuild utilizing factory bottom end with the addition of CP pistons designed to work with factroy rods. I too battled with what to do as far as keep it NA or full forged build and go nuts. In all reality my budget wasnt as high as yours so I decided to keep it NA with the ability to run low boost for around 800whp later on with Meth injection. I'll have a total of around $8k into it all said and done with doing it myself. Once you go down the rabbit hole of where you're going, the hole may tend to go deeper and deeper past your $25k budget.
My build:
Freshened SBE with additon of CP Forged pistons -4.6cc
Calico recoated the rods after big end needing a light hone after the ARP rod bolts
AI 280 heads being refreshed by LME
RPM B3 cam
ARP Main studs and Rod Bolts
Keeping Monster LT1-S twin disc
If it were me in my opinion I would go with the Monster Triple Disc LT1-S. Also you can't use ARP flywheel bolts as you need their GM bolts that they modify to clear the clutch assembly.
I've been following Unreal(Nick) on FB page as well and can see he's also been down the path. Seems to have been there and done that. But at the end of the day it's all up to you. Enjoy your build and I look forward to the end result.
Last edited by spartan8270; 08-15-2019 at 10:26 AM.
Yup that is the plan, at least until I get too deep in the hole hah.
Still think NA is the way to go? I just kept getting hung up on the fact that I could never go for more power if I wanted more because everything would be designed around NA.
I guess it all depends on what you plan to do with the car.......cruiser-street car that see an occasional trip to a drag strip and/or 1/2 event, or will it spend time on a road course too ?
You craving more power to be used racing the car, or just for the bragging rights ?
My HPR 468 is getting ready for it's first startup, but I knew all along I was staying N/A and drive it on the streets of Phoenix in our brutal summer temps.
Sorry about the engine failure. I recently went through the same thing, but my cam core wore down and ended up wiping my main bearings. To my surpise the rods were pristine (20k miles). Car was a H/C/I making 620whp on 93 oct for a couple years. I decied I wanted to keep it N/A and improve upon the build while its out so I decied to do a full fresh rebuild utilizing factory bottom end with the addition of CP pistons designed to work with factroy rods. I too battled with what to do as far as keep it NA or full forged build and go nuts. In all reality my budget wasnt as high as yours so I decided to keep it NA with the ability to run low boost for around 800whp later on with Meth injection. I'll have a total of around $8k into it all said and done with doing it myself. Once you go down the rabbit hole of where you're going, the hole may tend to go deeper and deeper past your $25k budget.
My build:
Freshened SBE with additon of CP Forged pistons -4.6cc
Calico recoated the rods after big end needing a light hone after the ARP rod bolts
AI 280 heads being refreshed by LME
RPM B3 cam
ARP Main studs and Rod Bolts
Keeping Monster LT1-S twin disc
If it were me in my opinion I would go with the Monster Triple Disc LT1-S. Also you can't use ARP flywheel bolts as you need their GM bolts that they modify to clear the clutch assembly.
I've been following Unreal(Nick) on FB page as well and can see he's also been down the path. Seems to have been there and done that. But at the end of the day it's all up to you. Enjoy your build and I look forward to the end result.
Soooo, I ended up going similar to this route. I completely ditched my original build and switched to a NA setup. I have edited the original post with the new build.
Thanks to Nick for letting me blast him with messages and getting knowledge in return.
I know my new build probably isn't perfect and there may be some other items down the road I'll have to add and touch up when more funds come in. But I think it will be super fun on the street, allows me the option in the future to beat on it in drag, 1/2 mile, autocross, or road race events if I so choose (not competitively, but just to enjoy the vehicle). The larger cubes should hopefully get me a little power and torque under the curve to make it feel fun around town, and hopefully will mostly be bullet proof for the future. And will be a lot of fun to compile the parts and piece it together myself with some friends over the next few months.
Everything is ordered and on the way. Now it's time to wait on everything to arrive, the machine shop for the block, and Advanced Induction on the heads (approx 4 week lead time)!
I keep going back and forth but think I'm going to move forward with WCCH heads over AI. Half the lead time and have received better customer service with some questions I had, so just going to move forward with them even if I leave 5-15whp on the table.
I've been horrible about updating this thread, but things are moving along. All the parts have been ordered and arrived, however still waiting on the darton sleeves/machine work to be completed.
In the meantime, I have been doing a number of smaller things. I just received in my heads from WCCH. They said my valves were ruined from AHP because they lapped them when they should have left them alone, so I got some new del west ti/mo intake valves installed.
Last weekend I installed a Walbro 450 last weekend and got that just about buttoned up but haven't connected the crossover tube yet, I'm not sure how I'm gonna tackle that properly. This weekend I installed DRM struts all around, lowered the stock bolts, put on a new ZR1 rear sway and bushings. I prepped the radiator with the new fan setup and the new AC condenser, I had my friend clean up my sump tank and a few other parts from the metallic goodness of bad bearings. I'm getting my headers ceramic coated. I'm also working on painting my headlights black while everything is down. Many other little things too...
So basically it's crazy right now. I was hoping to be done by now but in reality that was never gonna happen. I probably should have just dropped it at Cordes and kept it simple, but I've learned a lot and hopefully will feel accomplished when it's done. It is very satisfying having a car work day and knocking out a whole bunch of stuff. Once the machine work is done I should be able to just crank through a whole bunch of stuff and get this bad boy on the road again.
08-14-2019, 07:19 PM
My Rod Coating Failure Build Thread
