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[Function And Form] Sleeper DIY 10-Second Turbo C3… Part 13

Carl addresses a backfire then heads off to the dyno! Were the results satisfactory?

Carl’s 1977 Stingray build is on the road, but the troubleshooting and work left to get into the 10s is far from done! Before we dive into today, if you missed any previous episodes for Carl’s 10-second turbo build, (or need a review), here are the links: part one, part two, part three, part four, part five, part six, part seven, part eight, part nine, part ten, part eleven, and part twelve. Each episode is a quick read, with lots of pictures.

New Bonus Feature: Compilation of Carl’s videos at the end of each episode

Viewer Advisory: This build has some serious meat on the bones, as Carl has some crazy technical skills (especially with electronics), and he is going to tap into all of them to turn his 1977 Stingray into a 10-second quarter-mile monster!

Today’s first order of business is troubleshooting that backfire, as Carl explains, “I’ve been having an exhaust backfire since I put the car back together and changed over from the 5.3 to the 6.0. I assumed I got dirt into one or more of the 80lb injectors while I re-assembled the car. I changed over to 1000cc injectors (92 lb) yesterday and that fixed the issue. Engine sounds way healthier.”

Next up, Carl is working on boost control, strapping down the engine, and improving the cold air intake. Then he plans to take her to the dyno and then the track. His goal for the dyno is 700 to 900 RWHP, and he hopes to hit 10.0 seconds in the quarter mile at around 135 mph. Those are ambitious numbers!

Well, how did Carl’s expectations compare to reality?

Carl remarks, “It really didn’t go exactly as well as planned. I spent most of the time trying to have it make more than 1 lb of boost. Turns out I forgot to tighten one of my intake hose clamps. Of course it was one of the ones that are almost impossible to see. Anyway, finally found that and started making boost.

Got up to about 6psi and the rear wheels were slipping on the roller. So I strapped the rear down tighter and now the right wheel is rubbing the body on the passenger side while on a pull… Next time to the dyno and I’ll raise the rear coilovers to avoid this and also I’m going to shave some of the body over the wheel well.

So the only dyno charts I have are two incomplete pulls to about 83 mph (probably around 4500 RPM) and engine was really not tuned yet. Made 417 RWHP through the automatic. There’s a lot more in there.

Yikes, just 417 RWHP?!? Yeah, there is a lot more in there!

In an effort to explain the numbers, Carl says, “I didn’t get much time actually tuning, so it’s still running pig rich under boost and my boost control is not all there yet. But I do have lots of log data to take home and I’ll do some tuning at home, off the dyno, from all the log data I gathered. When logging, the AEM records pretty much all of the possible parameters every 1/1000 of a second that you can play back whenever.”

So, what does Carl have left to do? Here is his updated to-do list.

– Drove it the other day with the windows closed for the first time and it was a little loud on the right side. Maybe I’ll beef up the sound deadening on that side.
– Finish installing the A/C / heater.
– Gotta change the seals of the T-Tops to keep the rain out.
– Install a lock on the passenger side to fill the hole there now.
– Do a little more with the crankcase vents.
– Install a one way valve to keep boost from getting into the power brake reservoir.
– Install the door bar so I can go to the track.
– Install the passenger side door card.
– Get the windshield wipers working.
– Fix the high beam switch.
– Add some more interior lighting.
– Clean up the body at the nose and the tail where the previous owner glued on replacement ends and prime it to look like the rest of the unpainted car. I don’t think I’ll paint it for a while. People like the “patina”.
– Transfer the new calibration that I created from all the log data from the first dyno session.
– Gotta make some changes to the Dyno Mode screen.
– Raise the coil-overs and bring it back to the Dyno and put down some real numbers.

I’m tired just from reading all that! Aside from the skills, the patience from Carl required for a build like this continues to amaze me. This is a good time to come up for a breather. We have the fastest-growing Corvette community on our Facebook page, with over 159,000 followers (40,000 since January!). Come join other hardcore enthusiasts and let me know what you think so far of Carl’s 10-second turbo build, Douglas B.

Video Compilation

Video 1

From Part 2

Video 2

From Part 3

Video 3

From Part 11