J5isalive

If you are on Facebook you may have seen some of the below pics already; i tried to expand on some things because its much easier here than on Facebook.

I have a fairly robust post in the track section of the forum about the development of the car, admittedly I do need to do an update to that thread but I have seen that many people from the C8 community don’t venture into that section of the forum so thought it would be cool to show those how the other side lives 😉 This has been a project for a couple years now, its really getting good at this point and we have learned a ton along the way. A lot I have shared with the community and some I haven’t. The uproar from people as we pointed out the shortfalls and compromises made in the car when it was first released were very fun to deal with… the corvette community is certainly a special group of people, haha.

Feel free to go read some of what we learned here: https://www.corvetteforum.com/forums...-modified.html

Wanted to give some update some updates on the car since we have made some cool changes in the past few weeks that people may be intrigued by.

First, thanks to MRR for producing their new track wheel Forged FR43, its an 18x10 / 18x12 wheel with the perfect offsets. Months ago Carlos and I traded messages and notes with regards to the right offsets for 18s, using what I had learned and what Carlos had gathered after producing 1000s of sets of wheels he really hit a home run on these wheels. Fit is great. They are lightweight, and include an uncoated knurled bead to help hold the tire in place. I love my forgeline wheels but I was a little sick of running spacers to get the offset perfect so I’m pumped to get these on the car. Here are some pics….










The next update I have been working on was an intake update. I had been seeing some interesting data from track sessions; as we continue to push the car and shoot for laptimes we started to notice the car fall off after a lap or 2. I leaned on Cicio Performance a little bit to help diagnose but it didn’t take much, he knew the issue, IATs & the car pulling timing. The car is VERY sensitive to MAF readings. The car is completely over engineered from an engine cooling perspective, much better than the C7 in nearly every regard however the intake on the car is a bit of a compromise… It’s the perfect intake to maintain trunk space (Gotta fit those golf bags!) and be completely unobtrusive. My car being a track car affords me the chance to make some changes here and use some space to our advantage. Now before everyone claims I’m wrong here and starts preaching to me that “The cars at Ron Fellows don’t pull power” or “My C5 track car from 15 years ago makes me an expert”; please keep in mind I am not trying to sell you anything, I’m only documenting my journey, We didn’t get here by guessing either. Trying to extract every last 10th out of the car you start to micro analyze the data and things become apparent.

What I did was modify a K&N intake; the K&N intake comes with a heat shield that blocks it off from the engine bay and more or less seals the intake compartment from the engine bay… I took this design a step further, put more heat shielding on it, modified the MAF tube because the one that comes with K&N’s kit sucks… I sourced a MAF tube with proper air straightener to ensure the MAF gets a clean signal. You may recall in Paragons intake shootout they mentioned that the K&N had the worst MAF signal, this is because the MAF tube is right after a radius bend, I switched this out to a straight MAF tube with air straightener, works perfectly and idle trims and other fuel trims appear to be very happy.

The next piece of the puzzle was COLD air, we didn’t want any of the air from the side blades, the air from the side blades isn’t ambient… again, I’m not trying to start a war here with this comment… Sorry to burst everyone’s bubble, its not cold air coming into the side blades. I leaned on some friends here to help me solve this problem, I think we came up with a pretty trick solution. Taking a page out of the C8 Racecars play book we came up with a hatch scoop. 5 3D printed prototypes later we have a nice piece that I spent the weekend doing some body work on to make it look good enough. Still fine tuning it in the trunk, I’m using the scoop to provide cool air to both the intake and to keep my remote reservoirs on the MCS 3 Way shocks cool, without the scoop these would get so hot in the trunk that they couldn’t be touched until they cooled down after a track session. I’ll be building a full custom airbox but as it is right now the scoop is functioning quite well and doing what it was designed to do.



Here is what I used for motivation:







Here is the result:








Heading to Road Atlanta on Tuesday of next week. We have gone 1:29’s on a 200TW tire, we are hoping to dip into the 1:28s on a similar tire. Once someone comes out and says they have also run a 1:29 at RA in a C8 we’ll throw a slick on the car and really put down a time… so someone please come chase the time to give me an excuse to buy some slicks. HAHAHA.

Here is a full list of mods to the car, the power mods look cool but they do pretty much nothing, so don’t get too out of control trying to make the car faster with engine mods, make it sound how you want and be happy until a real tuning solution is available:I think that covers the bulk of it. May have missed a thing or 2 but the core pieces are there.

Kracka

Would you mind sharing some pictures of the inner workings of the modified K&N and how the scoop feeds it?

J5isalive

Since you asked nicely...an unfinished project in there.
Still need to order some carbon fiber to build the custom airbox. As of right now the scoop sits directly above the filter, and feeds directly onto the filter. My trunk is acting as a large airbox right now... not ideal but there is a huge temperature difference with the scoop than without. I'll build the airbox and change the filter design a bit but for now it will get the job done good enough but not ideal.

I actually ordered a bluetooth temp monitor and will post some results of with the scoop, without the scoop, sideblades intake air blocked off, sideblades intake air open. I hope to do that testing at the track on Tuesday.

Kracka

That is really interesting! K&N's filter is massive; too bad their MAF pipe is less than ideal. I'm guessing while designing & testing the concluded it was "good enough" for the average consumer and the fuel trims would compensate. I would agree that the intake design seems to be the main compromise in the factory layout while on the C7 it was probably on the opposite side being the exhaust manifolds (and of course the cooling system capacity). Thank you.

J5isalive

This is what the K&N comes with... needless to say it doesnt take a brain surgeon to realize this isnt going to work well. Also take 10 seconds and analyze the stock system and you quickly see how the stock system produces laminar flow across the MAF. I incorporated all those ideas into my modification to the K&N system. I think we got it right now.

Kracka

K&N got one of the key features right in their drop-in air filter: the internal air divider
Would have been nice to see them incorporate it into their intake design as well.

None of the aftermarkets duplicated the internal airflow straighteners from the factory MAF tube. Truth be told, I expected Halltech to. K&N really needs to go back to the drawing board with theirs, especially after Paragon's findings. Just feels rushed and incomplete. aFe could improve a bit too with larger filters (which I've since added to mine) and of course the airflow straighteners. At least Paragon found the aFe and Halltech MAF signals to be acceptable.

J5isalive

K&N got it right with the heat shield though. The heat shield is quite robust and fits well. I would have bought the kit just for the shield (essentially thats what i did). It fully blocks off the engine bay, its a very nice piece.

Racer X

OK, very interesting. I appreciate the hard work and tedious testing that you are doing. I assume this is primarily a track car. The added scoop doesn't affect the street look too much. As designed, I am guessing you do not drive in the rain. How did you come up with the inlet size and shape? What is the inlet area versus the MAF or MAF tube area? How did you choose the inlet height off the deck? Is in the laminar flow or clear of it. Are you an engineer by trade, or are you kind of wing it? Not that winging it is a bad thing, many very successful racers have done great things just by trying different things. Smokey Yunick comes to mind.

Good Luck!

Nice artwork on the driveway!

Kracka

I was curious about that, good to know. The pictures they published make it hard to tell. It was definitely one of my considerations before ultimately settling on the choice I made. It's funny, there is no perfect choice, but rather we all pick the one we feel like we can better perfect the best!

J5isalive

The boundary layer of air was considered in the design of the scoop. Unfortunately; that's kinda all i can say about it, the design wasn't a guess, it was flow analyzed, and we had input from some people that know a little too much that don't want to be named in the project. Was happy to get their help but also must respect that they dont want any credit here.

Just noticed I didnt answer all your questions... I'm not an engineer or remotely close to it, i'm an accountant. Lucky to have a long list of friends in the industry that have helped along the way, pro racers, team engineers, industry experts, etc. This entire car is a collaboration really, using everyone that Cicio @ Cicio Performance knows, using the team at MCS and their engineers, leaning on our pro drivers contacts for help. The amount of hands that have made an impact to this car cant be stated enough; i throw out dumb ideas and lean on my friends to help me make it a reality that functions.

I'd like to take credit for the artwork but there again; had to bring in a ringer for that work. My 7 year old daughter.

Racer X

Thanks for the answers. I appreciate the non-disclosure of people that don’t want it. The question was answered, not guess work. Just used to the old timey huge hood scoops like on the Boss 429 Mustang that made similar power with headers. it is good to have friends that know stuff, and can do stuff you can’t.

J5isalive

I hate the answer as it feels like a cop-out, but its the truth. Nothing on the car has really been done at chance. Have way too much data on the car, but now as we have finally breached the 1:30 barrier at Road Atlanta i just think all the data is that much more valuable. Its been a fun project.

A lot of the time spent on suspension tuning should translate well over to the Z06, so i'm excited for that as well.

Just realized i forgot a couple mods; i'll edit the above list.

NoMatter

As always great work.

Still need to throw some slicks on and see what times can be had.

Nimbustwo

John, I bought my car with the engine appearance package which looks like it might somewhat restrict engine heat from being extracted from the engine compartment. I’ll be doing Spring Mountain in a couple of weeks and temperatures will be in the 90s. I’m tempted to remove the trim. Do you have any thoughts on this?
Thanks for the update on your car. I’m very interested in seeing how well your cold air intake works.
Also thanks for Verus side skirts info. I think I will go with that setup. Rocker panels already have picked up a lot of rubber.
My car is back at the dealer to resolve my CAN bus 1 problem. Hopefully they’ll find something this time.

J5isalive

I dont think they necessarily restrict getting heat out of the engine, heats going to rise up regardless, open your hatch after each session to let heat out of the engine bay as the fans bring cooler air into the engine bay. The main issue (From my perspective) about tracking with the appearance package is the extreme heat impacting the appearance package, from what i remember those pieces have a little heat shielding on the bottom of them, i'd take them off just to ensure that the heat doesnt change the color of the clear coat on the piece negatively. Keep them for street driving.

The verus sides are fine... they help a little at keeping rubber off the side of the car, but also just keep in mine they are flat pieces of carbon infused plastic... its just a few rivnuts holding them onto the car. They arent substantial really. I like how they look though! Took all of an hour to install them.

I'll keep everyone posted about the Cold Air Intake. I received my temp probe to get some better testing over the cooling characteristics and will try to get some IAT information to go along with that.

J5isalive

Gonna need you to throw down a low number! We'll run the slicks eventually this year i'm sure... just trying to decide if i want to change the color of the forgelines before throwing slicks on them.

Nimbustwo

Good advice John. I checked with the dealer today and they think they found a short to ground in the CAN bus 1 at the rear of the car. They’re still trying to isolate the exact location. Hopefully it will be fixed by next Thursday so I can do the PCA event at Spring Mountain.

GSpeed

You guys have done a great job with that car. Benchrace me for a bit: What would it take to get to 1:19?

J5isalive

1. Thanks for the help with the bearings!

1:19 at Road Atlanta? I wouldnt even know where to begin there..... need to lose 750-900lbs for starters, slicks... and even then i think thats just deep into the 20s, still probably need a **** ton more power to get to a 1:19.... not many cars running that pace. Lets go off C8.R, i think they ran a 1:16, at a weight of 2,700lbs. haha, thats a real uphill battle to get to those levels.

You have really made me think hard on this as its now my second edit...haha.... Lets say a set of slicks netted us a mid 1:27 (thats giving us a 2.5 second advantage over a super 200 tire), we'd still need to get 7 more seconds... at that point we'd need massive power/power to weight... lets say we are able to hit 150 on the front straight and 170-175 down the back straight... i still dont think that the best lap time there would be much better than a 1:23-1:24. The level of refinement to the car to get any deeper than that would be pretty intense.

GSpeed

Its a pretty massive leap to get to a 1:19, you are right. Ive built C6s that have been 1:19, 1:23, 1:25, 1:27. Your 1:29 we all know is really impressive, so if you were to give it the "race car treatment", I think you are pretty close in your estimation on what it would take. 500-700lbs less would net a sub 1:25 as it sits. Add motorsport ABS and slicks and I think a 1:21/1:22 is an easy goal. Add 200 whp, and I believe a 1:19 is in the cards for sure.

We are building one swansong C6 this year, and then after that, it will be mostly focused on the C8 from the race car development standpoint.