'93 454 TBI in California...

[Andrew7]

The only non-catalyst legal systems I've ever seen involve an EPA exemption. A friend of mine has a Ford truck with no catalysts, and an exemption sticker on the radiator support--I think it's essentially a no-fire-in-tall-grass "farm truck" exemption.

Johnny Franklin is begging for a $10,000 fine; or series of fines.

ok I had that wrong it’s before 1975

 

[Andrew7]

That's not legal in any state.

ok I had that wrong it’s before 1975

 

[Busted Knuckle]

Hi guys -

I am wondering if anyone has any recommendations for California legal bolt-ons for a '93 454. This is not in a GMT400, it's in a P30, but this always seems like the best resource when it comes to TBI truck motors.

I'm looking for improvements in the mid-range ... Freeway RPMs hover around 2500, and I'm hoping to thicken that up for better hill climbing etc. Being in CA whatever it is needs to have a CARB EO# ... Being old engines, those parts are often hard to find and documentation is outdated etc.

I'm thinking along the lines of intakes and headers... Seems like that's the easy place for improvements. Any thoughts?

The Edelbrock intake isn't worth it. The engine already has plenty of flow. Exhaust wise, make sure its a full 3" after the Y in the system. I like Magnaflow muffler and cat, 95509 cat - 12579 muffler. Change ALL sensors. Change the distributor if over 150,000 miles. Be aware the dist is a ***** to stab with the engine in the truck. Switch over to the 1996 Vortec fuel pump (Delphi) and clean up the fuel pump to chassis ground. Change the fuel filter every 10,000 miles.

 

[Schurkey]

Or TEST the sensors, only replace what shows actual problems. O2 sensors have a known service life. The rest can go ages and ages in most cases.

If you need a fuel filter every 10K miles, you need a different gas station. I don't change OIL filters that often. I bought a '97 K2500, 180K miles on it, that had every sort of neglect you can imagine. Fuel filter was so seized to the metal fuel tubes that I couldn't unscrew the flare nuts--had to cut the tubes and splice in new sections of tubing with new flare nuts on a new fuel filter. I considered that it might be the ORIGINAL filter (but I have no idea how old it may have been.) I was just sure that was the cause of my low fuel pressure. Once I got the old filter out...I had no trouble blowing through it. Yes, there was some rust in it, but it wasn't plugged at all. Kind of a bummer, now I have to trace the real cause of low pressure.

I've had issues with TBI distributors; specifically the permanent magnets that ride alongside the pickup coil crack and become weak, leading to ignition problems. The problem is that the aftermarket is flooded with Chinese garbage. Most any "replacement" distributor is going to be questionable. I salvage used but good-working Delco distributors in preference to "new" Chinese stuff.