Jay wrapped up the tops this weekend, and I'll be picking them up after the holiday. I can't wait to see them in person.
For anyone interested, Jay has done a bunch of videos about how he made these. They are full of TONS of info.
Jay wrapped up the tops this weekend, and I'll be picking them up after the holiday. I can't wait to see them in person.
For anyone interested, Jay has done a bunch of videos about how he made these. They are full of TONS of info.
Done is never really done...
Updates to the rear aero can be found here - https://grassrootsmotorsports.com/forum/aerodynamics-presented-nine-lives-racing/prepared-rear-spoiler-how-badly-am-i-compromising/176944/page2/#post3146410
Had a great weekend for the Camaro. I took a ride on Saturday and managed to make great progress on two projects.
Larry at 20sqfab fixed up my end plates on the rear spoiler for the Camaro. The original design had a fundamental flaw that made the rear deck lid hard to remove, so we did some fixes there. You can see everything we've done with the rear aero here - https://grassrootsmotorsports.com/forum/aerodynamics-presented-nine-lives-racing/prepared-rear-spoiler-how-badly-am-i-compromising/176944/page1/
I also stopped by Jay's place and picked up the new t-tops for the Camaro. The original glass tops, even after stripping them down for the mold, were around 17lbs each. These new ones are just a tick over 2lbs each. I still need to work out the mounting system, so these are just set in place, but let's just bask in their glory for a moment:
those look pretty fracking awesome... nice work!
Without a doubt, that is the best a t top has ever looked. Well played.
Man, this car is so rad. Hope we get to share a grid again soon :).
Wrapped up the rear spoiler on the car. Really stoked about how it turned out. It's at the edge of the rules, but every way I have checked it's legal. Excited to see if I notice a difference.
Just a quick video recap of how the rear spoiler came together, and some info on the t-top plan. Excuse the lateness, as this one has been sitting on the old hard drive for a while. I should have another one out soon.
And a quick preview of what's in the video coming out next week.
Including a little "science."
Not a Camaro update, but I did help some friends get their project further down the road.
Been keeping busy getting ready for the dyno and doing other weird stuff.
The homemade "oven" is for curing the carbon fiber t-tops.
Video on the rest coming soon.
Home stretch for the new season/dyno. Here is a deeper dive into the new breather setup:
I also noticed that the area behind the front tires of the car were becoming gravel traps, so I quickly made some small inner fenders to help prevent that. I forgot to take "before" photos, but I grabbed some from earlier in the thread so you can see what I'm covering up.
I just used the same ABS plastic that I used on my front air dam.
Waiting on confirmation today, but we should be back at the dyno at the end of the month to wrap up the tune. I should be waking the car up from it's slumber either this weekend or next.
Yeah, I have been thinking about putting screens over the sidepod inlets for the Fmod. Right now its a standard post-race activity to vacuum the sidepods out for gravel. Lots to be said for simple things that keep it clean.
Dyno is scheduled for the 27th. Fingers crossed that we got all the bugs worked out.
Dyno is still on for next weekend. Doing the important things before then...
In reply to Gimp (Forum Supporter) :
That is a superior touch. Well played.
Love this build thread. So many ideas to crib for my Challenge build.
DeadSkunk (Warren) said:Love this build thread. So many ideas to crib for my Challenge build.
Crib away!
In reply to Gimp (Forum Supporter) :
I'm trying to come up with fender flares kinda like yours, but I don't feel like doing all the work you did. I've been thinking I might just buy a steel trailer fender and use the inside surface of it as a mold. If I can end up with my Corolla sending off the same sort of vibe this car does I'll be quite happy. It'll just be at 2/3 scale. 
DeadSkunk (Warren) said:In reply to Gimp (Forum Supporter) :
I'm trying to come up with fender flares kinda like yours, but I don't feel like doing all the work you did. I've been thinking I might just buy a steel trailer fender and use the inside surface of it as a mold. If I can end up with my Corolla sending off the same sort of vibe this car does I'll be quite happy. It'll just be at 2/3 scale.
I'd love a mini-me.
Dyno day has come and gone. The good news, the car is home and (almost) in one piece, and it made more power than ever. The bad news - we haven't fixed the issue we had last time, and I learned I'm not always as smart as I think.
Before the dyno session, I did a few things, some you've seen in this thread:
- Holley Dual Sync distributor
- Nut/bolt/oil change
- Raised the limiter on the MSD box
- Fixed exhaust leaks and removed the spiral muffler inserts
- New plugs gapped at 0.045
- Replaced voltage regulator on alternator
- PCV delete
- Checked valve lash
- Replaced secondary wideband (Innovate MTX-L Plus) withe new AEM unit, which might already be dead
On Saturday, I brought the car back to Kinetic Autoworks. When we were here last, the car made 370hp (the most it had made on a dyno was 380hp, about a decade ago when Randy had the motor), but had an issue at 6600rpms where the car would go rich and lose power. This time around we did much better on power, but still have the same issue at 6600rpms.
We made our first pull and hit 390hp. Frankly, we all thought that was probably going to be around our best number, based on last time. The difference this time is Mike finally had really good timing control, and he went to work.
(all the pulls for the day overlaid - you can see the consistency of the 6600rpm issue)
After a dusting of timing and some fuel cleanup, we got our best numbers. 420hp/413tq.
Here is the unedited, most power run:
We did learn some important things.
This car has never had a charging system, and that's totally a huge oversight on my part. When I installed the alternator, I installed it as a one wire alternator without realizing, it isn't.
I'm kicking myself. A trip to nationals, a few local events, a tour, a dyno day, installing a new voltage regulator, and I still didn't notice. Mike and Larry get all the credit for discovering this issue. I had never seen full charging, but assumed that I had to rev this alternator to get it. Nope, it never charged. The first few runs were all at 12.2v. Mike and Larry rigged up the alternator to make it charge, and it did, but we still never saw over 13.1v, even at full song, and the issue wasn't (sadly) fixed.
So we wrapped up the session, and walked away with some things to fix and some theories. I'll get to those in a moment.
So, obviously the alternator is out. I have a new one on order (one wire this time) and a new coil on the way, just in case. I'm also simplifying things at the back of the car (removing one battery) to help troubleshoot things.
So, there are a few theories/ideas here:
1. Charging system not up to the task means spark going out at high RPMs. We know that we are having a charging issue, so replacing the alternator and coil don't feel like throwing parts at the problem. We are thinking the lack of charging, and low voltage, mean the coil doesn't have enough time to recover at that high of a demand. The coil (MSD Blaster) might still be good, but they are cheap enough to have a backup.
2. Valve float. This motor has made peak power at 7300rpms before, but the valve springs have been on that motor for 15 years. They could be weak and causing valve float. The only thing that doesn't convince some of us is the little uptick in power at the end. Usually, valve float means it's done done.
3. Lean misfire. We may be dropping fuel pressure at 6600rpm, and that could be causing a lean misfire. It would still show rich on the wideband because of the unburnt fuel. We will be putting a camera on the fuel pressure gauge next time.
So what does it all mean and where do we go from here? Well, alternator and coil are going to go on, and if I then see 14 volts or more with the car running, I know I have solved that issue and we schedule another session. We will run a camera on the fuel pressure gauge to make sure the pump is keeping up. If we still have the issue, I'm going to assume it is valve float, set the limiter to 6500rpms, and send it for the year. Realistically, I don't need that much RPM for most events on the east coast, and at Nationals, I'll have plenty of other factors against me. Come winter, I'll pull a spring, test it, and maybe do top end rebuild (and probably do something stupid like a bigger cam).
That about sums it up. I'd love to hear your ideas and theories. Anything I may have missed or need to check? Let me know!
I have the logs now, and since someone in another thread asked:
At 6674rpm, just before things drop:
Injector duty cycle: 64.6%
Fuel flow: 285.2 lb/h
AFR: 12.1
Battery: 11.6v
MAP: 99kPa
At 6827rpm, the bottom of the dip:
Injector duty cycle: 45.4%
Fuel flow: 171.7 lb/h
AFR: 10.6
Battery: 11.7v
MAP: 91kPa
The fact that your voltage was more or less constant leading up to and at the bottom of the dip tells me that isn't your issue.
Why does the injector duty cycle drop off and the AFR increase though? Are you running closed loop with an AFR target? That's suspicious for sure...I'm pondering that if your valve springs are clapped out and hit a grumpy harmonic allowing for some float with a little rebound at the redline, that might result in going way rich since open exhaust valves would let unburnt air/fuel out. And that would trigger the ECU to pull fuel as you show in the logs. It's total speculation on my part though...the one time I dealt with valve float it was much as you described: at the point that they start to float there was just nothing the higher you went in engine speed.
If you suspect the valve train is worn out...I'd go after that next. It's sounding like something you need to do anyway, so do it and see if it is solved.
Does the ECU you're using have a separate table for voltage adjustment? If not, you're going to get to do your fuel all over again once you have an actual charging system. 
I assume you're fine here because I can't remember the last ECU I tuned on that didn't compensate for voltage.
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