Didn't pass emissions. Help?

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DoubleDingo

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LMAO I'd love to

You do and then you have to pass even stricter emissions standards. Stick with stock, LS is for those that have money to burn to build something and then tinker with. Stock, you dial it in and run it.
 

nabeshin

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How am I able to tell the RPMs without a tach? Is there a tool I can buy?

I passed emissions with all of your guys' help, but I still need to adjust my carb correctly now. I leaned it out as much as possible with the engine still running smooth. I got home and tried adjusting to max vacuum with the gauge and now it smells really rich. Maybe it is because I have a lot of vacuum leaks, so I might try adjusting it like how you said.

Some multi-meters can be set to read RPM with an inductive pickup. It's what I use.

You cannot tune the carb effectively with vacuum leaks all over. Timing needs to be done in combo with the carb tune as well.
 

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How am I able to tell the RPMs without a tach? Is there a tool I can buy?

I passed emissions with all of your guys' help, but I still need to adjust my carb correctly now. I leaned it out as much as possible with the engine still running smooth. I got home and tried adjusting to max vacuum with the gauge and now it smells really rich. Maybe it is because I have a lot of vacuum leaks, so I might try adjusting it like how you said.

You can buy a used tachometer gauge that mounts in the truck and either mount it in the truck or just wire it up to give you the reading and leave it in your toolbox. You can also buy an old mechanics tach meter and get the RPM reading.
 

thecantaloupeman

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You do and then you have to pass even stricter emissions standards. Stick with stock, LS is for those that have money to burn to build something and then tinker with. Stock, you dial it in and run it.
Yeah I’m never gonna ls swap it. I won’t have the money for quite a while. I’d much rather rebuild the stock 350. I guess I was dreaming lol. But come to think of it I’d much rather have a modded 350 than an LS.


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hoagster

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You do and then you have to pass even stricter emissions standards. Stick with stock, LS is for those that have money to burn to build something and then tinker with. Stock, you dial it in and run it.

In Cali if you have the right model, no smog required and it's just as expensive to build the right 350 as it is to do a ls swap!
 

Frankenchevy

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In Cali if you have the right model, no smog required and it's just as expensive to build the right 350 as it is to do a ls swap!
Or if you live in the right zip code there aren’t emissions tests, or any inspections for that matter.
 

DoubleDingo

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81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
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Carb'ed Vortec 350; 1972 L48 350
In Cali if you have the right model, no smog required and it's just as expensive to build the right 350 as it is to do a ls swap!

Or if you live in the right zip code there aren’t emissions tests, or any inspections for that matter.

True, and true. If I lived in my home town I wouldn't have to do emissions testing on my newer stuff. The OP does live in an emissions testing part of Colorado, so an LS would cause the stricter testing.
 

Bextreme04

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How am I able to tell the RPMs without a tach? Is there a tool I can buy?

I passed emissions with all of your guys' help, but I still need to adjust my carb correctly now. I leaned it out as much as possible with the engine still running smooth. I got home and tried adjusting to max vacuum with the gauge and now it smells really rich. Maybe it is because I have a lot of vacuum leaks, so I might try adjusting it like how you said.

I paid a little extra for a digital timing light with tach. It has come in handy quite a few times. Alternatively, you can look for older tach/dwell gauges, or get a used tach if you can find one.

You CANNOT effectively get it running right or tuned properly with vacuum leaks. The best, and probably cheapest, thing you can do to get it running right is find and fix all of your intake or vacuum leaks. Once you have found and fixed all leaks, THEN properly set up and tune your carb.
 

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Catbox

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I have picked up used Tach's at the swap meets for as little as $5.
I have some speaker wire and alligator clips connected to one that is just for things like this.
Find the right places to connect it and you are in business.
 

Chevyguy

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Yeah I’m never gonna ls swap it. I won’t have the money for quite a while. I’d much rather rebuild the stock 350. I guess I was dreaming lol. But come to think of it I’d much rather have a modded 350 than an LS.


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I'ed convert to fuel injection. The way they keep adding more alcohol to gasoline eventually carburated engines won't want to run due to all the carburetor seals getting destroyed by the alcohol.

Clayton

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