Xleratorss

A quick background, I have a 73 camaro with a use complete stock LT4, but I only had a standalone harness for OBD1 setup sooo. Can I use a stock un modified 95 OBD1 computer to run and mangage my stock unmodifed 96 LT4?? The only thing I swapped was the KM. Will I have any issues with the 95 computer running this LT4??

whitehooptie

The knock sensor will not work. But it will run.

Daniel6718

yea..think they are differant tunes...lt4 has bigger cam ect...is say if its a true lt4 both wiuld not run optimal...but yes all you should have to chance is the km

Injuneer

The OBD-I PCM will run the LT4. You would need some programming. You already noted the need for the LT4 KM, but you also need to replace the 96/97 100kOhm knock sensor with a 93-95 4.5kOhm knock sensor. You will not be able to connect to some of the devices on the LT4 engine, like the crank position sensor (misfire detection), EVAP purge vacuum switch, etc.

whitehooptie

Not the module in the ECM but the sonsor on the side of the block. OBD1 and OBDII sensors are different.

Xleratorss

Thanks for the replies, I feel alot bette about my decision.

Whitehooptie: Yup,I did change out the Knock Sensor which I stole off of my 95 LT1.

Daniel6718: This is a true complete LT4 Top to bottom from a 96 Collector's edition Vette. So the injectors and Cam are LT4s


I found out the hard way that my LT4 OBDII computer will not work with my OBDI harness when I saw some "extra" sensors. I learned quickly that the LT4 is an OBDII setup. I then decided to use my OBDI computer and ran it that way. I can't tell if it's running correctly yet sence my 73 has not left the garage yet.

What kind of programming needs to be done??
Would the fuel map (not up on my computer programming) need to be changed due to the increase in fuel demand?? Is the demand increased because of the larger injectors? Maybe I can just use my LT1 injectors and be fine too??

Thanks again!

Daniel6718

tune for the lt4 cam...its completely differant

Injuneer

The LT4 cam isn't a lot different than the LT1 cam. The LT4 does not use the LT4 HOT cam. The big difference is the injector flow constant. The LT1 uses 24# injectors (programmed as 24.9 #/HR) and the LT4 has 28# injectors (I don't know the exact flow constant). Its goint to run very rich at WOT if you don't put the correct flow constant in the PCM.