976speed

what is an obd1 converstion and is it worth it. also what is obd2?

Dave '97 Z28 M6

OBDII (OBD2) is a more powerful car computer (PCM) that can monitor the function of catalytic converters and track missfires. OBDI cannot do these things, thus the OBDI conversion for your car would ignore your rear O2 sensors (or probably sims in your case, since you have no cats), and the crankshaft position sensor (missfire detection). In terms of our cars, and from a performance perspective, some of the pros and cons are as follows:

OBDI pros: - gets a few more HP, according to tuners
- good variety of cheap/free software for datalogging/tuning
- less pesky fault codes

OBDI cons: - lower RPM limit than OBDII
- PCM sometimes has trouble with high-stall TC's

OBDII pros: - higher RPM limit
- a cure for many people's high-stall TC issues

OBDII cons: - tuning software is much more expensive

In reality, both the early (OBDI) and late (OBDII) systems in the LT1 F-bodies work quite well and are emminently tuneable for any modifications.

Now....... to answer your question: An OBDI conversion is an OBDI PCM, modified internally to work with the different knock sensor used in OBDII applications. This OBDI conversion will ignore the rear O2 sensors, as well as the crankshaft position sensor (CPS). OBDI conversions are typically "plug and play", meaning you simply remove your old OBDII PCM, connect the OBDI conversion PCM, and you're done.

I'm happy with my OBDI conversion. Is it worth it? That's up to you. Are you planning on doing your own tuning?

Hot94Z28

If you plan on doing your own tuning and/or want less expensive software go for it

Tricked-Out-Toy

Can you just grab a ODB1 PCM from a wrecked car and swap in the knock sensor from the OBD1 car and be fine? Ill be doing all the tuning so thats not a problem Im just trying to figure out if you can swap them back and forth? Ive already eliminated the rear O2's so what else does the OBD1 PCM see that needs to be added?