New 345 SV engine data

[Craig]

Ok after what seems like an eternity I got the rebuilt 345 engine fired up.. 30 over pistons and stock cam, light porting on the heads(air injection hump removed) 2 barrel manifold. 2 1/4" exhaust going back to a Y pipe with a 3" dynomax muffler.
This is both a fuel and timing controlled system.

I followed the setup procedures. Turned the key on and set the TPS to .57 volts, followed by setting the IAC, and setting the timing to 0. Fuel pressure 13 psi. I log data the whole time the engine was running, but once I got all the setup stuff done, I log some data for a couple minutes. The engine is brand new and tight, so I am only running it a few minutes at a time. Letting it cool down a bit. I used an IR gun to check temp and everything is looking good so far.

Here is the data after doing Bills initial setup procedures.

[Bill USN-1]

Data looks pretty good.
The TPS is still high at 2.6%.
You also have a TPS and an EST error.
Recommend you clear the faults before the next log run. Also uncheck the raw box.

Then when done save the BLM table too.

Install looks good.
Looks alot like mine but with a pretty alum intake.
What chip are you running?

[Craig]

Thats is Jeff's red paint job on the engine, the flash makes it look a lot like yours. Its killing Jeff that I had him install a faux aluminum intake. ( just painted with silver hammerite) but I like the 2 barrel design for adding a TBI unit.
using a stock TBI off a 92 caprice, and the ECM from a truck with the stock chip.

What should the TPS be at? (Edit.. 0 ) I also noticed that at WOT (engine off) the voltage was 2.5v vs 4.5-5 v I have about 5 TPS sensors ( new style) that I have collected and they all read about the same. (Edit.. will double check to make sure TBI is opening up all the way Doh, as I was in the cab using the pedal)

Will save the BLM table tonight. Current display setting is Latest narrow. and I uncheck the raw data.

[Bill USN-1]

A faux finish on an intake......that's just wrong. Stay off the DIY network while working on the scout.

The BLM table saves all of them. I normally view the wide avg when logging.

Looks like you answered most of the others.
Make sure the throttle is going full open and full closed.

For the ecm to set the idle mode it looks for the TPS to be below 1.2%.
The IAC numbers didn't look bad so it should be more of a TPS adjustment then the min idle screw.

[Craig]

Originally Posted by Bill USN-1

A faux finish on an intake......that's just wrong. Stay off the DIY network while working on the scout.

No not a faux finish, just a "fake" aluminun manifold (painted silver ) I just tossed in the French word for fake/faux LOL

Does it make any difference what size the holes are in the manifold? Meaning there are spread bores, vs 2 barrel, vs bored out to 2" two barrel manifolds?

[Craig]

Ok I warmed up the motor for a couple minutes and here is the log file after warming up the motor.

[Bill USN-1]

To be efficient the holes should blend in.
I ran my first one just bolted on to the stock 2 barrel.
I now run the 2 barrel with the holes bored to match the adapter.
I did it when the manifold was off duri ng the rebuild.

Data looks fine.
I need to look up the code to check idle speed. seems a little high.

[Craig]

Forgot to list my injectors, it's what came with the TBI unit when I pulled it. GM part # 17084327 for the 5.7L Cop Car Flow lbs/hr @ 13psi 65

I have a second TBI as a spare (untested at this point)and it has GM part # 5235279 for the 5.0L Flow lbs/hr @ 13psi 40

So next step is a test drive if the data looks good.
When the IAC was disconnected, I set the rpm to 500.

EDIT.. So much for a road test, I just finished installing the rear driveline and a new hub on the rear 14 bolt axle. Still need to add oil.
Now for the bummer part, tomorrow I teach a night class, Thursday is Valentines day, need to take the wife out and Friday I fly out of town for work, so there won't be much progress until I fly back next Wednesday . I will have access to the Internet.

[Craig]

Back in town, and got more data. I drove around the neighborhood for about a mile and then let it cool a bit and then back out for more drive time. Varied the speed a lot and everything seems to be running fine. Still being easy on it.

I cleared the table at the start of the day, but just keep hititng save after that.

[Bill USN-1]

Data looks good.

[Craig]

Just to clarify, being easy to me means not a lot of drive time before letting the rings cool down a bit. I got an auto so I gas it in first and shift to second manually. Sunday I got in some more drive time, but noticed the BLM's vary a lot now that I'm gasing it a lot more. I'm doing short burst to seat the rings. stop sign to stop sign. I plan on driving to work Tuesday once the mud flaps are installed.

[Craig]

I drove the Scout to work, about 20 miles on the hwy. I'm trying to understand what all the numbers mean. Bill I know you been doing this a long time and I have a big learning curve.
I know that a BLM of 128 is the correct air fuel ratio.

Can you post one of your BLM table and log data? Trying to see how the data varies as you drive. Maybe I'm barking up the wrong tree here.

[ldo_marlin]

Your wide average BLMs look OK for now. Read up on Bill's Faq for tuning notes. It's easy to do. 128 is 14.7:1 air/fuel ratio.

Here is what I do. Get it below 128 (a tiny bit rich). Go tune timing at this point. Once you have timing dialed in ( you can spend eternity doing this) . Go back to correct the fuel. Again, I try to stay a little bit below 128. I feel the motor runs better a bit below 128.

By the way, during the timing tune, you will notice your motor will sound "different". Quieter, smoother but it will roar like a race motor. This is a sign of timing dialed in. Use the 80/20 rule and don't pull your hair out trying for an absolute perfect tune. Remember that the tune should be robust in all conditions (air temp, fuel quality, elevation, towing a load etc....) If you tune it too perfect for a certain condition, you will be tuning again and again and again...

[Craig]

Originally Posted by ldo_marlin

Read up on Bill's Faq for tuning notes.

I looked for his tuning notes, Got a link? I did not see one about timing or tuning. Looking on the Thirdgen now, but get side tracked with other FAQ items

[Bill USN-1]

Basic Chip adjustments