Initial Baseline - High RPM

[newbaufish]

All -

I was able to connect to our car last week for the first time with HPT to start it and get a baseline for how it starts/runs. It's a LS Swap, stock components 5.7 with a Magnuson 2300 blower kit added on it which ran in the corvette a while ago. I have several things we need to tune but I'm trying to keep it basic and take it slow as I got overwhelmed quickly with the layers trims which can change fueling/spark.

I'd appreciate initial thoughts on how to control the RPMs directly after start as it goes to almost 2K RPM, which isn't ideal when Oil isn't fully through the engine. if this log isn't detailed enough, what PIDs would you add to investigate what is running up the RPM? whether the car is 70 or 180 degrees it behaves the same way on startup.

I won't bore you with the long voyage I went through to slow it down with idle settings and removing trims to see what can be done and learning along the way. I was able to get the RPMs down but it was too low to maintain oil pressure and couldn't raise it again, then I ran out of time...I would love to settle it down first so we're not panicked and can make small changes along the way!

Thank you in advance for the thoughts.

Tim


log after idle changes.hpl
1966 Magnuson Base Jan.hpt

[Alvin]

Did you change the throttle body to something else?

I do not see anything in that tune to cause a high idle other wise. Check for vacuum leaks.

The tune needs a lot of help...

[newbaufish]

Checked and throttle body is Stock GM # for the 2000 corvette. I did notice the LTFT's were 25% today when reviewing the info. that can't be helping.

[5FDP]

What your fuel system like? Fuel pressure? What fuel injectors are those and do they have the data for them?

Needs a 2 bar map sensor too. Needs to be running the 2 bar OS too.

That engine will grenade with those timing tables too.

[newbaufish]

I will check on fuel pressure, that's a good point. I don't have the injector data, as we bought the engine and my uncle heard it run before taking out of donor so we assumed it should just run the same and need fine tuning given the Magnuson system was in place. Of note, I can see the flow rates in the tune are over 2X the stock and the timing is only off by 1-3 degrees from a corvette 5.7 tune from repository.

Thanks!

[newbaufish]

Injectors are the #60 Deka Siemens. #107962.

[5FDP]

Needs the proper injector data and you need to install a 2 bar MAP and the 2 bar OS for tuning this.

[newbaufish]

I did change the 2Bar and it's stable now without trims running. THanks for the eyes. Will go back and verify the injector data as it seems way off on initial investigation but it's hard to validate 100%