CK5
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Blazer K5 1985 SMOG story

TBI is good stock. Start getting away from stock (in terms of engine modifications like cam, headers, etc) you can start to have issues. Don't need to get into the technicalities, but it cannot adjust fuel accurately outside of a small window where the O2 sensor is used, not when you need more fuel.

Really just about ANY OEM EFI system isn't going to handle much in the way of modifications without tuning, and the TBI systems aren't any different there. However, they can be easily tuned to accommodate changes, but one will still likely run into issues when it comes time for emissions checks if that's needed. I did that for years when I was playing with 1st gen S10s, though the problem today is that they're such old systems that it may be difficult to find someone able and willing to do the tuning, especially considering none of them are flashable. The ECU needs to be opened up, and have the memcal inside changed out.
 
though the problem today is that they're such old systems that it may be difficult to find someone able and willing to do the tuning, especially considering none of them are flashable.

Yep. Tuning over the internet is possible, but takes way more time than anyone trying to make a buck is going to take to get it perfect. When you start talking about buying the equipment to do it yourself, and the learning curve that goes with, most just aren't willing to make the effort.

I cant recall what chip is used with the TBI stuff when going the DIY PROM route, but the SF512 chips aren't even made anymore, which is what TPI used. So the systems are getting archaic enough that even the tuning hardware is going the way of the Dodo. There are alternatives, but more cost, and CA doesn't make anything deviating from stock easy.
 
But how do you know it's 1991 and not 1992 or 1993? There is bunch of crate engines around and the thing with them is that hey don't originate from specific year vehicle.
You have to have the complete engine out of a later model and all the smog that came with it, You cannot just put a crate engine in it, as it is still an 85 no matter which crate engine you buy.
 
I cant recall what chip is used with the TBI stuff when going the DIY PROM route, but the SF512 chips aren't even made anymore, which is what TPI used. So the systems are getting archaic enough that even the tuning hardware is going the way of the Dodo. There are alternatives, but more cost, and CA doesn't make anything deviating from stock easy.

Same thing we ran into with the Fieros. I have a small stash of PROMs sitting on the programming bench for just this reason (even though my Fiero is long gone, lol), and there are compatible EEPROMS available, though they're not a direct plug and play interchange. They socket correctly, but there are some programming changes that need to be made. Well, available at least when I last played with them a couple years ago, anyways. They weren't exactly sourced out of the surplus clearance bins then, so I'm sure they'd be available today as well. There's a guy by the name of Bill Howell doing TBI swap kits for non GM vehicles, particularly the International Harvester trucks, and I seem to recall that he was doing some TBI tuning for these applications. So I'd assume that there are still options out there, but outside of stuff like his swap kits, it may well be a case of diving into a rather steep DIY learning curve.
 
You got a junkyard close by?
Go take stuff off and take a LOT of pictures to show you were it all goes.
Use the carb you have and JB Weld some fake fitting on to accept the hoses a CCCarb would normally take. Also, stash wires up under the air filter hat so they look like they go to the carb.
Make sure the tech can't see the check engine light on your dash, take the gauges out. BAM, it never came with a computer. If they ask say "hahaha dude, it's a carburetor, no light that I know of".

If you need a pump, get a pump or better yet grab a whole serpentine belt system. This truck can be smogged for $100 (price of serpentine belt system, junkyard addmission fee, and manual)

The smog referee will run the numbers on the engine block and see what year engine it is.

A smog referee is a person who will make sure the engine swap was done correctly and all smog equipment is correct. He is not a smog tech. If you make what you currently have work, you do not need to see a referee. Just go to a smog station and pay the $65 for the inspection.
 
Make sure the tech can't see the check engine light on your dash, take the gauges out. BAM, it never came with a computer. If they ask say "hahaha dude, it's a carburetor, no light that I know of".

Even here in Arizona that would never fly. Their computers tell them which cars came with a CEL, and if that light doesn't come on properly at KOEO, BAM, instant fail. Regardless of what is blowing down the tail pipe.
 
No, you hook the light to the oil pressure sensor. Key on, light must work, start engine, light must turn off. Unplugging wont work.

You can always register your rig in Tuoloumne county...no smog for the life of the rig until you sell it. The kicker is the po box fee (100$ annually).
 
See, that is a useful rebuttal to my reply. This is not rocket science and doesn't have to be hard.

Jebus Chris!

Get this thing going and then worry about your TBI swap while you have 2 years to figure it out.

Welcome to smogging older vehicles
 
No, you hook the light to the oil pressure sensor. Key on, light must work, start engine, light must turn off. Unplugging wont work.

You can always register your rig in Tuoloumne county...no smog for the life of the rig until you sell it. The kicker is the po box fee (100$ annually).

As an aside, whether helpful or not, does the CEL on CCC setups also "blink" with KOEO before staying lit, like TBI and TPI does? And is that part of the smog test? Or do they not get that specific?
 
Never seen it, wouldn't doubt it these days. I still think the smog free county is the best option.
 
It needs a smog test to register to a non smog county, then no more smog.
 
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