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Discussion Starter #1
I currently have an LT1 out of an Ex-Police 94 Caprice Classic. I will be rebuilding it and putting it in my 1948 Hillman (pics on my webpage)
My question is, How much of the emissions controls can I remove from the engine. I don't want to run Catalytic converters, do I still need to run all 4 O2 sensors? I primarily want the engine for performance and fuel injection.

Thanks
Marty
Mesa, AZ
 

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You can safely remove all of the emission stuff but you will need to have the PCM reprogramed to remove all the functions that the emission pertain to. PCMforless.com will do it for aroud 100 bucks. If you are doing any upgrades like a cam, injectors, or head work they can tweak the computer for that as well. I have not had mine done by them yet( currently doing an LT4 conversion), but I have heard great things about them. Thier web site has a Q&A and a price listing . Good Luck

The Wolf
 

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48,

I don't really think you can remove all/most of the LT1 sensors and still have a viable and reliable result. The computer needs those inputs.

I've got a similar engine, a '95 9C1, that I was going to use. However, I guess I'm a little too "old school" and decided not to tangle with it.

I would suggest contact/research with the tech folks at one of the ECM sites.

Good luck.

I was just on another board and found this link which might be helpful:

http://www.lt1swap.com/links.htm
 

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LT1

You can remove a few things from that engine.
You can remove the EGR tube and EGR valve and block those ports off at the intake using block off plates. You can also remove the A.I.R. pump, as well as the cat converters. Since yours is a '94 its an OBD I car and should only have 2 O2 sensors, not four. The two sensors are located in the exhaust before the cats, so removing the cats is not a big deal but you need to keep the 02 sensors. If you have four sensors then you may have an '96 OBD II engine, not '94. Do you have a crank trigger sensor at the bottom of the timing cover? OBD II cars had that. The 4 sensor cars had the second pair of sensors after the cats so you would need to do one of two things
1) get O2 SIMS (simulators) to plug in place of the second pair, about $90 I think
2) convert to OBD1 computer.
You also may need a simple program adjustment to compensate for the removal of the EGR system. At least to keep the check engine light off if you wire that back in place.

md
 

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Discussion Starter #5
Re: LT1

Yes, its a 94, my bad, only 2 O2 sensors. No crank sensor.
I'm sure I will need to do a bit of reprogramming of the computer?
Check Engine line will be re-installed on the Hillman. as will the rest of the harness.

Marty

y5e06 said:
You can remove a few things from that engine.
You can remove the EGR tube and EGR valve and block those ports off at the intake using block off plates. You can also remove the A.I.R. pump, as well as the cat converters. Since yours is a '94 its an OBD I car and should only have 2 O2 sensors, not four. The two sensors are located in the exhaust before the cats, so removing the cats is not a big deal but you need to keep the 02 sensors. If you have four sensors then you may have an '96 OBD II engine, not '94. Do you have a crank trigger sensor at the bottom of the timing cover? OBD II cars had that. The 4 sensor cars had the second pair of sensors after the cats so you would need to do one of two things
1) get O2 SIMS (simulators) to plug in place of the second pair, about $90 I think
2) convert to OBD1 computer.
You also may need a simple program adjustment to compensate for the removal of the EGR system. At least to keep the check engine light off if you wire that back in place.

md
 

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Remove the cats, block off the egr, tie off the loose lines and get a chip reflashed to account for this. You can keep your smog pump if you wish or dump it and get a free spinning pulley in its place.

The conversion isn't that difficult.
 

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Discussion Starter #7
Siggy_Freud said:
Remove the cats, block off the egr, tie off the loose lines and get a chip reflashed to account for this. You can keep your smog pump if you wish or dump it and get a free spinning pulley in its place.

The conversion isn't that difficult.
The smog pump on this car is driven by an electric motor and not the engine. Found a fellow that will flash the computer quite reasonably. PCMFORLESS.COM

Thanks guys....my buddy who is a mechanic keeps insisting I should keep the EGR system to help with knocking under hard acceleration. Will the knock sensor from the LT4 help with this?
 

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If the sensor detects knock its going to change the timing like it would on the LT1. The chip reprogramming should help readjust your system to account for no EGR. If everything is blocked and sealed, and the chip done correctly, the sensors should do the rest.
 

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Discussion Starter #9
Siggy_Freud said:
If the sensor detects knock its going to change the timing like it would on the LT1. The chip reprogramming should help readjust your system to account for no EGR. If everything is blocked and sealed, and the chip done correctly, the sensors should do the rest.
Thanks for the info, much appreciated.
Marty
 
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