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86 350 swap to 383 pass ca emissions?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by AntAZBlaz, Jun 30, 2003.

  1. AntAZBlaz

    AntAZBlaz 1/2 ton status

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    I'm ready to buy the enigine and i was wondering if any one has passed emissions with this type of set up. i realize that some work would have to be done but would it even be possible? I'm looking at the gm performance 383 crate engine. and i have not chosen a carb yet so does anyony have some sugestions. This would be an 86 cali truck being tested in AZ. thanks
     
  2. dyeager535

    dyeager535 1 ton status Premium Member

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    I'll start off with the response you will get 99% of the time here: Q-jet if staying carbed.

    You can make almost any engine pass emissions sniffer testing, you just have to try harder. /forums/images/graemlins/smile.gif

    Visual is usually the tougher of the two to fudge, but if you have all the external stuff in place, it's pretty unlikely they will check the block numbers, even then, doubt GM (if you are talking about a crate motor) marks their 383's externally with anything that tells their displacement.
     
  3. AntAZBlaz

    AntAZBlaz 1/2 ton status

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    Not having the experience of using various carbs why do you suggest the q-jet? do different people make q-jets. is there a particular cfm that should be used on this application.
     
  4. supersize75

    supersize75 1/2 ton status

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    I believe they came equiped with them, but I may be wrong as usual /forums/images/graemlins/thinking.gif
     
  5. AntAZBlaz

    AntAZBlaz 1/2 ton status

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    I checked the specifications page and it only listsa 350 as the largest gas engine for that year unless something is missing?
    king
     
  6. dyeager535

    dyeager535 1 ton status Premium Member

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    Q-jet will work on everything from a 250CID motor to 455+.

    Only two *stock* CFM's, 750 or 795. (800 some say) Edelbrock makes an 850, but thats overkill for most. Difference on the 750 and 800 is made up with the primaries, so economy suffers some with the 800.

    Stock on GM vehicles from 1965-1990 in various forms. I like the '75+ "emissions" carbs myself, but anything that isn't computer controlled (unless thats what you want) is fine. Cars '81+ all had CCC (computer controlled Q-jet+ other stuff) but trucks didn't necessarily, all the way up until 1987 on the SBC.

    Reasons for Q-jet are the small primaries (250 or 300CFM depending on 750 or 800) for economy, adaptability (fit just about any engine), ease of use (they are NOT complex, regardless of what some think), commonality, and reliability. (both for off-road use, and in general)

    The Q-jet can have some quirks to it if purchased used. Some may bolt on and run fine, but the settings and usage was so varied, that the jetting could be off enough that you might run a bit lean or rich at cruise, and secondaries almost always can benefit from fine tuning. The *tuning* part is where some would say that the Q-jet is complex, and that is really only because of the myriad of parts available to do so. Many primary rods and jets, different power piston springs depending on engine vacuum, many secondary rods and hangars, as well as idle mix and choke.

    I'm putting that in there because it's fair to you. You MAY be able to get a used one and run it no problems, or you MAY have to do some tweaking with it. But either way, it's still an excellent carb, IMO the best *all around* carb there is. Some may be the best at some things, the Q-jet does everything well.
     
  7. BorregoK5

    BorregoK5 1/2 ton status

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    I passed my 415ci stroker as a 350ci in Southern Cali. Your 383 should be more stealth and built right should do just fine. What they may look for are A.R.B (Air Resource Board) numbers on items like the exhaust and intake manifold or an aftermarket carb. These numbers reference an items ability to be as good or better than the original polution tested equipment. With all the visual stuff in place you should be fine at the tail pipe if you dont get too radical inside. I set mine up for all out grunt with Towing style mods and a Q-Jet carb. While you can get other carbs that are ARB certified, you'll find that the Q-Jet has some of the best off-road characteristics without going fuel injection.
     
  8. AntAZBlaz

    AntAZBlaz 1/2 ton status

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    Thanks for your feedback I just wanted to make sure that it was possible to get through emissions with this type of set up. I didn’t want to have to wait a year just to find out that there was nothing that I could do to pass with a 383. Thanks for the input on the carbs too if you have anything else to add about it please let me know.

    king
     
  9. AntAZBlaz

    AntAZBlaz 1/2 ton status

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