• Got the Contributing Memberships stuff finally worked out and made up a thread as a sort of "How-To" to help people figure out how to participate. So if you need help figuring it out, here's the thread you need to take a look at -> http://www.corvetteflorida.com/forums/showthread.php?t=3581 Thank you, everyone! Rich Z.

The tuning chapter...

I would think that a vehicle speed sensor would have something to do with this also.

On a side note, it's really kind of funny. I used to think some carburetors were complicated(especially when I took the top off my first Quadrajet and springs and ball bearing flew out). And when fuel injection came along in 1985 It was intimidating because we knew so little about it and we couldn't adjust it. But it has proven so reliable that we seldom give it a second thought. At least until I get behind a 1970 Chevelle at a red light and you have to turn your A/C to max air because you're choking on the fumes from a rich carb condition! Probably not too many that can/will work on a carb motor these days. Or setting the points on the ignition. My, haven't we come a long way!?
 
Took the car out for a shake down cruise to Mexico Beach with some of the local Crawfordville crowd. Round trip was just under 200 miles, and the car ran really well the entire trip. So this is the longest trip made yet with the car, and it passed with flying colors. :thumbsup:

Oh yeah, it was even driven through heavy rain and didn't melt on me, so that's a good sign....
 
I took the car out for a drive today as a sort of final test drive. The changes I made concerning the idle problem I had appear to have done the trick. Idle remains stable around 900 rpm +/- 10% no matter what. Throttle response is excellent. Gas mileage is VERY good, sometimes hovering at 30 to 31 mpg while cruising. The log file traces look very good with no strange humps or valleys anywhere. I didn't run it up into boost, though, and I don't think it is necessary. The tuning changes I made since the last time I did that shouldn't have affected anything with the fuel mixture or timing, and it looked fine to me then.

There was another problem I had a while back with the DIC giving me a Reduced Engine Power message on engine startup every now and again that I believe I have fixed. It appears I was affecting how much vacuum was in the manifold by how I was playing around with the tables that control engine starting. From what I can figure, if then engine starts up too "weakly", there isn't much vacuum in the manifold and by association, the brake booster, when the PCM runs diagnostics on the brake system. So I think the PCM determines this is a fault in the brake system which is exhibited as a fault in the ABS and traction control systems. So the PCM basically shuts down the engine with a REP fault. At least that appears to be the case by the changes I made to the startup tables. Time will tell, I guess.

Anyway, unless something else shows up, I'm stamping the tuning chapter as being DONE. I'll be pulling out the wideband sensor stuff and consider the car as finally FINISHED.

BTW, the car drives REALLY well. Real tame coming off of a dead stop and even nearly all of the low speed surging is gone. There is still some, but I think it is just the nature of the beast. Heck, even my C6 Z06 does that time to time, and from what I can recall, so did the stock LS6 I originally had in my C5Z. I think it is just amplified by the suspension mods in my car, plus the Pfadt polyurethane motor mounts taking out all the drivetrain slop that rubber grommets and bushings cover up.

So, as best I can tell, FINALLY done.
 
Last edited:
Rich I think you'd put the "pros" to shame with what you have learned of their business in the last three years. BTW I am discarding the bad memories of some of the azzholes who claimed to be experts and cost you a damn fortune for just muckng up the build.
:shrug01:
 
I think that the BIG plus in all of this "crap" has been Rich's ability to learn
more about the inner workings of his Vette in 2 + years than the rest of us
probably ever will know. It's GOTTA be a good feeling to feel some surging
and say to yourself........"I know what that is, and how to fix it"! Me......
all I can say is "WOW some surging............better get this bad puppy to Rich
REAL QUICK!" :lmao: I compliment you on your perseverance, and attention
to detail, Rich! :thumbsup:
Andy :wavey:
By the way, and NOT to hijack the thread, but how's the Tiger Shark
front end coming along.......?
 
Yeah, it's been interesting, to say the least. And DEFINITELY a learning experience in a whole lot of ways. Mostly about how naive I was at the start of this project, and certainly gullible about what people would tell me. I am astonished at the blatant bald faced lying people are willing to do to grab a buck. I presume that they didn't think that I WOULD find out the truth. Or maybe they just didn't care, knowing that really nothing could be done about it. Heck, I tried to send Chris Harwood to jail and the Calhoun County Sheriff's office wouldn't do it even with black and white evidence. They did get me back some of my money, though, so I guess it wasn't a complete loss. But in my opinion, Chris Harwood DESERVED to go to jail for what he did to me and a bunch of other people.

As for Aaron Scott, honestly, looking back on it all, I feel like I was looking at two sides of the same coin comparing Aaron Scott to Chris Harwood. For all his supposed good reputation, I certainly learned that he was not at all above lying to me. With some things, in my opinion, he HAD to have been either lying to me or incompetent.

All I can say is that I sure can pick them....

As for the tigershark front end, it's still sitting on my work table in the garage. I did talk to a guy at the last local Crawfordville cruise in who owns a restoration shop out near the airport. I'm planning on stopping out there one day to take a look around. But I'm not in too much of a hurry with that. The wet sanding I did gave me a great shine and the car looks super from 6 ft. away. It's only when you get close up that you can still see the cat claw scratches that the car suffered at Aaron Scott's shop that I was afraid to try to sand out and burn through the clear coat. When I mentioned to some people I wanted to get the entire car painted they looked at me like I was nuts. Some thought that it HAD been recently repainted.

In any event, I'll deal with that bumper fascia when I feel like it. In the meantime I want to do some driving with the car without it being all wired up for data logging. Early on I was not only data logging, but running a mounted camcorder for every trip so I would have a visual and audio record of when the expected explosion happened while driving the thing. Fortunately that didn't happen. :thumbsup:
 
Last edited:
Glad the journey is over Rich. Enjoy your car! I have appreciated the story but glad it turned out the way it did. What a ride, right? Quite the roller coaster. Your perseverance is admirable. So what do you do for an encore? What is your next challenge?
 
85vette said:
So what do you do for an encore? What is your next challenge?
Click to expand...

Well, if I want to maintain the same quality of life I've been through most of the past four years, I'm thinking about maybe taking up homebrew root canals on myself while I'm flushing hundred dollar bills by the handful down the toilet. I guess I've gotten kind of accustomed to that feeling......
 
Rich Z said:
Well, if I want to maintain the same quality of life I've been through most of the past four years, I'm thinking about maybe taking up homebrew root canals on myself while I'm flushing hundred dollar bills by the handful down the toilet. I guess I've gotten kind of accustomed to that feeling......
Click to expand...

:lmao::lmao::lmao::lmao:

I hope you're laughing as hard as I just did! I have a friend that's an Alligator trapper. I could see if he will let you wrestle one from time to time so you won't lose that feeling that you've become accustomed to! :rofl1:
 
Aargh...

Yesterday Connie and I took the C5Z out to Apalachicola and St. George Island to meet up with Mike and Donna for lunch. Car ran just fine. Up till we stopped in at Myway Seafood to stock up on some shrimp. When we were getting ready to leave, I kept getting Reduced Engine Power faults at startup. Had to try it several times before the error would go away.

Anyway, I went and made some adjustments in the tables that do the comparison of actual airflow to predicted airflow (C6101 and C6102) and raised the values 30 percent. The car started up fine after flashing the new tune, but obviously I need to run it for a while to see if that fixed the problem or not.

There is another value I need to fiddle with that controls the conversion of throttle body stepper motor steps in relation to the amount of airflow per step. Changing from the stock throttle body to the 90mm LS2 version changes this formula and there is a value (B4349) that is used to enter a scaler value. Stock is 0.0255. I have mine set at 0.0330. Some people say the value should be SMALLER for a larger TB, like 0.192, but when I use that value, the engine will not stay running after I blip the accelerator.

Since this REP is happening at startup, it's possible that the airflow values at that time are not correct, triggering that fault. Or it could also be an actual hardware intermittentcy. The only error code I can pull up is a P1516, which indicates a throttle position mismatch between commanded and actual throttle blade position. So it's possible that the throttle body blade position sensor might be flaky instead of something programmable in the tune. I guess I need to find a description of exactly what the PCM is testing upon startup to get a better feel for what this is telling me exactly.

Ah well, guess I don't want to get too bored with everything running perfectly on the car....
 
Yeah, looking at all these tuning tables and settings controlled and referenced by the PCM, it seems like a miracle that cars used to even run back then. Of course, none of the cars back then could even come close to the horsepower to cubic inch ratio easily attained today and still get 30 miles to the gallon on the highway.

Kind of makes you wonder what engines will be like 50 years from now.
 
Rich Z said:
Kind of makes you wonder what engines will be like 50 years from now.
Click to expand...

probably no better off than we are now if the EPA keeps pulling their stunts and keep adding more and more emissions crap to the engines while requiring less and less CO and other emissions....
 
Rich Z said:
Yeah, looking at all these tuning tables and settings controlled and referenced by the PCM, it seems like a miracle that cars used to even run back then. Of course, none of the cars back then could even come close to the horsepower to cubic inch ratio easily attained today and still get 30 miles to the gallon on the highway.

Kind of makes you wonder what engines will be like 50 years from now.
Click to expand...

Yes it sure does......
:shrug01:
 
As indicated in another thread I posted (http://www.corvetteflorida.com/forums/showthread.php?t=102142), I think I've got the tuning stuff pretty much the way I want it. The improvements I made to throttle response were pretty dramatic so I'm happy with where it is now.

Lately I've been playing around with developing a "valet tune" because I will likely want to get that new tiger shark bumper fascia I bought a while back mounted and painted, which will mean leaving the car there for several days. I certainly don't want to worry about someone joy riding the car (or stealing it, for that matter), while it is away from home.
 
You must log in or register to reply here.
Back
Top