New to forum with fresh tbi install.

[damanx]

I suppose I should introduce myself. I am a jack of all trades and a master of none.....

Now that the intro is out of the way, I'll jump right in.

It started out as a worn 2.8L 2 barrel carb engine in a 1985 S-15 truck. When that engine gave up the ghost, I put in a 3.4L from a 93 Firebird with 120k on the clock.

Here is a picture of the engine going in:



After a while, I realized that the old worn 2 barrel Rochester Varajet just wasn't cutting it, I upgraded to an Edelbrock 4 barrel manifold and a 390 cfm Holley carb.



Well, after fighting with the carburetor long enough, I decided it was time for another option.

TBI.

So, I did the research and realized that doing a TBI install would not be anything more than time consuming. Here are most of the parts, most of which came from a 1988 S-10 with a 2.8L. Then began the throttle body rebuilds and cleaning of everything.



When I finally broke down a got into wiring, everything went well. I did have to make an adapter plate for the TBI. I could have bought one, but I was concerned with the TV cable and throttle cable and location of transmission dipstick giving me an issue, so I offset the throttle body for those to clear, as well as wanting to use this intake and not the stock. Once all the wiring was installed, fuel pump put in and sacrifices made, it was time to start her up.

I'll be darned, she started the first time. After tweaking the timing and idle speed, and some time driving, I knew I made the right choice. I just wish I had made it sooner..........

I still need to tidy up the wiring.




Then came the fun of using Winaldl. So I happened to have this old Win98 cf-28 toughbook that I got from a local swap meet for 5 bucks. The touchscreen even worked as well as the battery. I just had to add a hard drive and an operating system. Once that was done, I built the vehicle powered aldl cable and was able to use the laptop to watch the readings. For a couple days until that laptop crapped out. Then it was off to the local computer shop for a usb to serial cable for my current laptop which does not have a serial port. After messing with port speeds and playing with the program, I got both TurboLink and Winaldl to work.

I was finally able today to get a report while driving home.

To preface the following pictures of the data, the plugs look on the slightly leaner side of tan. I am running the 2.8 throttle body with the 4.3L injectors. After verifying the fuel pressure and possibly upping it a little, I'll see what the numbers do then. I do need to get an eeprom reader.

Here is the BLM info:

Wide Latest
RPM \ MAP 20 30 40 50 60 70 80 90 100
400 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
800 0.0 144.0 164.0 128.0 0.0 0.0 0.0 0.0 0.0
1200 0.0 146.0 147.0 0.0 0.0 163.0 172.0 0.0 0.0
1600 129.0 141.0 142.0 159.0 162.0 164.0 169.0 0.0 0.0
2000 129.0 0.0 156.0 161.0 165.0 170.0 172.0 0.0 0.0

Wide Avg RPM \ MAP
20 30 40 50 60 70 80 90 100
400 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
800 0.0 135.3 131.0 128.0 0.0 0.0 0.0 0.0 0.0
1200 0.0 137.0 137.4 0.0 0.0 154.6 141.6 0.0 0.0
1600 127.0 138.3 154.7 163.4 168.4 164.0 166.1 0.0 0.0
2000 126.6 0.0 161.4 163.1 169.2 159.6 172.0 0.0 0.0

Here is the INT info:

Wide Latest RPM \ MAP
20 30 40 50 60 70 80 90 100
400 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
800 0.0 132.0 130.0 129.0 0.0 0.0 0.0 0.0 0.0
1200 0.0 133.0 133.0 0.0 0.0 158.0 149.0 0.0 0.0
1600 128.0 118.0 127.0 123.0 146.0 158.0 140.0 0.0 0.0
2000 128.0 0.0 126.0 145.0 129.0 145.0 158.0 0.0 0.0
2400 0.0 0.0 0.0 0.0 0.0 158.0 0.0 0.0 0.0



Wide Avg RPM \ MAP
20 30 40 50 60 70 80 90 100
400 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
800 0.0 136.5 128.5 129.0 0.0 0.0 0.0 0.0 0.0
1200 0.0 127.8 129.7 0.0 0.0 142.6 155.0 0.0 0.0
1600 128.0 124.3 127.2 127.4 138.5 148.7 156.4 0.0 0.0
2000 128.0 0.0 124.3 134.2 134.3 145.8 158.0 0.0 0.0
2400 0.0 0.0 0.0 0.0 0.0 155.4 0.0 0.0 0.0


Here is wide average for o2 sensor if that helps:

Wide Avg RPM \ MAP
20 30 40 50 60 70 80 90 100
400 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.451 0.000
800 0.000 0.525 0.090 0.004 0.000 0.000 0.000 0.000 0.000
1200 0.000 0.377 0.351 0.000 0.000 0.011 0.004 0.000 0.000
1600 0.224 0.418 0.422 0.462 0.490 0.307 0.190 0.000 0.000
2000 0.216 0.000 0.462 0.504 0.559 0.457 0.513 0.000 0.000

Anyways, thanks for reading and if you have questions/comments/advice, please add!

[EagleMark]

Nice work!

Don't think I've even seen a TBI on backwards?

Couple comments... try to move spark plug wires away from EFI wires, can cause feedback issues. Where is your MAP sensor hooked up? SUpposed to be on the rear (front) of TBI between fuel lines.

Your data is showing going leaner as RPM increase. Check fuel pressure!

TunerPro is like WInALDL on Steroids, and it will do the bin editing too...

[Playtoy_18]

Lol, S10 with camaro engine and fiero valve covers.

Looks like fun,i'm building a 3.1 turbo hybrid now.
Still haven't decided if i'll try OBDII or $8f though.

[damanx]

The nice thing about the camaro 3.4l is that the block is nothing more than a bored and stroked 2.8L block, so everything attached to the block matches except for no provision for a mechanical fuel pump.

The map sensor is connected to that port between the fuel pipes.

I'm going to check out the fuel pressure and probably increase it a little to see what happens.

The other thing I am curious about is wondering what the timing is supposed to be doing, I have a timing analyzer that I had hooked up at if I recall correctly, it was running about 40 degrees at 2k rpm at cruise.

On the mounting of the throttle body, on the s-10 factory manifold, it actually sits where the throttle cable bracket is pointing more towards 10 o'clock.

I'm going to do the pressure regulator mod on the extra throttle body that I have and see what affects upping the pressure a little will do. hopefully correct the lean issue.

[fasteddi]

Nice. Cant wait to see this progress. Welcome to the site BTW

[damanx]

Thanks for the welcome.

Just got a new higher pressure fuel pump installed. The old one was only running about 7 psi max. The new one, 115 bucks later is running about 13.5 psi.

Will have to readjust idle and the start from scratch on the numbers again.