CorvetteForum - Chevrolet Corvette Forum Discussion - C7 Tech/Performance

How do I "backup" a tune from the previous owner?

z2810inch — Mon, 18 May 2026 15:25:50 GMT

Hello,
Recently purchased a 2014 Z51 Yellow Convertible M7 that somewhere in its former life had a Magnuson Heartbeat Supercharger, long tube headers and Borla full exhaust. (Yes, she scares me).

She runs great with the installed tune (has a plaque on the engine that says "Professionally Tuned by Lashway Motorsports") but I am worried about what to do if I need a software update, etc from GM.

I have zero tuning experience. Do I just buy HP Tuners software and it'll be self explanatory?

Thanks in advance!!!

Squeaking sound coming from the pulley assembly. Does anyone had this sound before?

apsc — Mon, 18 May 2026 07:44:42 GMT

I changed the belt and tensioner 600 miles ago to fix this squeak. It went away, but now it's back.
It only squeaks after spirited driving when the car gets hot. If I drive gently, it’s perfectly quiet. Any ideas what to check next? Thanks in advance.

Here a link to the video of the sound, also added it as an attachment: https://www.facebook.com/reel/1529414198815136

Attached Files

IMG_5937.MOV (10.83 MB)

G M Tries to Screw Me

xlr8rvette — Sun, 17 May 2026 18:26:16 GMT

I have Novi Stretch Bras on both Corvettes. For ease of installation I braised a piece of metal to the bottom screws that need to be removed and replaced on the lower air dam resulting in a wing nut for easy on and off by hand. After 51000 miles the wing nut on the passenger side broke off. I went to the local Chevy dealer to buy two screws to rebraise a new wing nut onto. THEY WANTED $20. for 2 of the tiniest screws made !!!! I cordially refused their offer and drove 15 miles to another Chevy dealer who GAVE me the 2 screws saying "enjoy".
In reality the additional 15 miles to the other shop plus 15 miles home plus the 10 miles I drove to the first dealer totalled 40 miles.
Monetarily I drove 40 miles of which a portion was well over the speed limit...Lets say 2 gallons of gas at $5 = 10 The end result is I saved $20 by getting the screws free, however, still got screwed by paying $10 out of pocket for $5 worth of gas.

Torque wrench

kodpkd — Sun, 17 May 2026 13:06:04 GMT

If you use a torque wrench, have it checked for accuracy. Both of mine were way off.
I purchased a torque calibration tool.
I can calibrate your wrench if you are local. I am in Loveland CO.
I have a really good HazeMaker IPA in the fridge. :cheers:

Whats the trick to fitting a Katech 103mm?

Damnit, Laverty — Sun, 17 May 2026 04:44:16 GMT

Put my MSD Airforce on today, and when I went to bolt up the Katech 103mm, I couldnt get a second bolt in- the TB seems to be hitting a standoff on top of the water pump, circled below. Nobody's ever mentioned having to trim the water pump, so what am I doing wrong? Help!

o2 sensor issue

9sec — Sat, 16 May 2026 18:23:55 GMT

I have been battling a p0132 code for weeks if not months. bank 1 sensor 1 heater inop. randomly I will get a bank1 sensor 1 high voltage code but the inop heater is constant.

started chasing it and found the o2 sensor connector burnt from the header. I swore I would never do headers did them and knew this would happen!! so I bought a new upstream o2 sensor cut the burnt connector out of the harness and using a duetche connector I repaired all 4 wires.
wiring went as follows
sensor in header. ------------------- wire harness
blue wire --------------------------- violet/dark stripe wire
white wire -------------------------- tan wire
black wire ---------------------------- violet / blue stripe wire (found this to be switched power )
black wire --------------------------- black wire

now all I read the 2 black wires aren't polarity specific so they can be interchanged doesnt matter

this worked fine for 1 10 minute session. next day started car and codes are back afr is all over the place until the car is hot then they fall in line

questions I have for now are

1. is there only 1 power lead?
2. are the back wires ground?
3. looks like violet wires are signal wires correct?

if I have these wired properly why does the o2 sensor heater not work? new ac delco o2 sensor not eBay cheapies

I found this diagram but honestly I dont know how to read it I see the violet /blue stripe as the power I confirmed that but my colors aren't the same as this diagram

any help to lead the blind would be appreciated. im sure its something simple or stupid I did but im lost at this point. I do have an oem gm connectrpor and pins but to install it will require removing the header which is a major Pia and I dont see the difference between duetche roll pins and gm crimp pins
I also used a power probe to confirm with acc on the violet/ blue stripe wire is the only switched power source. the other 3 wires aren't lighting up the probe. should there be another power source?

doing more research and keep seeing g this in the description of the sensor itself. "saying special programming needed'. I ASKED MY TUNER AND HE SAYS NO IT DOESNT. could this be the root cause?

https://parts.gmparts.com/product/gm...ineBaseId=5920

Torque tube failing?

mharris1984 — Fri, 15 May 2026 14:24:06 GMT

I've had my C7 3LT A8 2016 for about four or five years now. And it's always had this shuttering or clunking noise That sounds like it's coming from the back, but lately it's been getting worse. It almost has a clunking sound like whenever you seat a torque converter onto a transmission, for anybody who's ever installed a transmission or a torque converter. It's kind of that dull thunk. At idle in Park or neutral It does get a shaky idol. I'm worried that it's the torque tube failing and if it's vibrating and making that noise with the torque converter. And if that's the case then I'm really worried about it destroying the seal on the transmission for the pump. Is there any signs I should look for to see if it's failing? I have a lift available so I can put it up and take off the plate to inspect. But I wasn't sure if their signs of failure that I can look for.

However at speed, the car and drive trane and everything runs smooth as glass.

I know people have talked about the shuttering of the A8 and the elusive triple flush thing. My car is going to roll over to 70,000 mi today and being 10 years old is definitely no warranty lol.

Any help would be appreciated before I go and remove the bottom plate and do some inspection. If anyone else has experienced these sounds and had something wrong or something for me to look out for with the torque tube. She is my daily driver, and I sit in the car for almost 3 hours a day In traffic and at just under 90 mi a day to working back, I definitely want to keep her running at her best!

( NEW ) PCV Valves not working ?

meikel24 — Thu, 14 May 2026 11:16:11 GMT

Dear fans, as asked in the previous post, to my knowledge, the PCV valves don't work on older models. Unfortunately, the PCV valve, just like the new ones I ordered, has no function after installation other than acting as a hose. If you suck into the removed valve from the intake side while the valve opening (engine side) is facing upwards, it closes. However, this is the wrong direction, and of course, it's not installed that way. If the valve opening points downwards, as it does when installed, no valve function can be reproduced. The new valve hoses on the right and left are no different from the ones previously installed. Could this be a design flaw by GM, since the valves were changed later? It's a Stingray Z51, which still has the two PCV valve hoses on the right and left. The hoses are simply clipped in and can be removed in seconds for testing. Perhaps the experts here on the US forum can answer this question.

2016 z51 M7 tuning

Headbomer — Wed, 13 May 2026 21:54:37 GMT

I'm looking to see how realistic tuning with different Maps is, I have had some German stuff and I know with a lot of those you can have different maps for burbles, flames, different power levels. Is that a possibility with a c7s? I've been told by a couple people that it's not something they can do but I don't know if it's something no one can do. Or for example having it where if you lightly hold the gas it burbles but doesn't otherwise

LT4 supercharger conversion on C7 LT1 Stingray HPFP wire harnesses?

Allen650HP — Sun, 10 May 2026 04:21:30 GMT

Hey guys. We will be doing a LT4 supercharger conversion on my C7 Z51 Stingray M7. Can anyone tell me if the existing LT1 HPFP wire harnesses plug's into LT4 HPFP ? Or do I need to prepare in advance and buy a LT4 HPFP wiring pigtail adapter harness for the swap? Highly appreciate your time in advance. Have a blessed weekend

2019 7 SPD Z06 - Gear Slipped Message - Help!!

Mr Ski — Sat, 09 May 2026 17:30:50 GMT

I have a 2019 Z 7 SPD, 5000 Miles
I changed clutch fluid and a new battery along with other fluid changes
Got a message on my dash when driving in Touring Mode- Gear Slipped?
What is this?
How to fix?

I did feel a slight grind between first and second earlier to this
I thought this was my fault, however I now think it might be connected?

Thoughts on both??

Moderators, I mistakenly posted on Z06 Tab

Valve spring replacement.

kodpkd — Sat, 09 May 2026 00:05:55 GMT

I will be replacing my valve springs soon. I am going to hook up my compressor with 150 psi, to the spark plug hole. Has anybody ever had a valve drop into the cylinder using that much pressure?

Dot 3 brake fluid

Vicorniner — Fri, 08 May 2026 13:43:02 GMT

Anyone hear about the delco dot 3 recall ? For particles in fluid? Does this mean since I just flushed my brake system I have to do it again? If so what to use? Ugh thanks

C7 hooking up a Battery Tender connection under the hood.

tednphx — Fri, 08 May 2026 02:48:58 GMT

Just purchased a 2016 Z51. Have Battery Tender brand maintainers in use in my garage. Connecting the maintainer to the truck battery is not an ideal solution. Is there any place in the engine compartment to connect a positive and a negative lead to charge the trunk battery?

C7 Z51 Ball Joint Part Numbers & Recommended Brands?

fonatig — Fri, 08 May 2026 02:47:35 GMT

Hey guys, I�m looking for part numbers for front and rear ball joints for a C7 Stingray Z51.

Also wanted to ask what brands people had good long-term experience with.
OEM / ACDelco? Moog? Mevotech? Anything else worth considering?

Thanks.