94 lt1 to a 97 need help quick
08-15-2018, 02:14 PM
#1
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94 lt1 to a 97 need help quick
I have a 97 trans am I’m putting a stock lt1 back in.the motor going in is from a 94.i was going to switch the reluctor ring and etc over but the distributor from the 97 will not fot in the hole in the cam.its not deep enough.i switched the timing gears over as well.my question now is can I put the 94 cover on and use the 94 distributor? Will the 97 distributor cap vented work on the 94 non vented? The 97 is new is why I ask.can I leave the crank sensor unplugged and it run till I get it tuned? I have the 94 computer but I don’t think I can use it. Please help thanks
Last edited by Jason62371; 08-15-2018 at 06:41 PM.
08-15-2018, 03:53 PM
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Re: 94 lt1 to a 97 need help quick
I know I have seen pictures comparing the two, but for the life of me cannot find them (Fred or Shoe will likely jump in). To change from a non-vented to a vented, check out Shoeboxes site: 4th Gen LT1 F-body Tech Articles
08-15-2018, 05:19 PM
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Re: 94 lt1 to a 97 need help quick
I just re-read your post.
As far as I know, both distributors work in the same fashion, regardless of vented/non-vented. The vent was added to help prolong the life of the distributor by venting ozone out of the distributor by pulling clean air from the intake elbow through the intake manifold. The computer requires the cam signal, and will not run without it.
I am not sure if the cap can be swapped between a vented/non-vented, but new or not, I wouldn't bother unless there is an actual issue with the cap. If you really want to do something, do the full swap to give yourself a better overall setup.
As far as I know, both distributors work in the same fashion, regardless of vented/non-vented. The vent was added to help prolong the life of the distributor by venting ozone out of the distributor by pulling clean air from the intake elbow through the intake manifold. The computer requires the cam signal, and will not run without it.
I am not sure if the cap can be swapped between a vented/non-vented, but new or not, I wouldn't bother unless there is an actual issue with the cap. If you really want to do something, do the full swap to give yourself a better overall setup.
08-15-2018, 09:21 PM
#8
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Re: 94 lt1 to a 97 need help quick
If you put the 97 cap on the 94 Opti base, you will only have one vent connection on the cap. You also need a second connection on the Opti base for the system to work. 94 Opti base (factory) doesn’t have that connection.
To put the 97 reluctor gear on the 94 engine, you would have to change the timing cover to the 97, because the 94 doesn’t have a crank position (CKP) sensor. The 97 only uses the CKP to facilitate the misfire detection required by OBD-2. The CKP is not required to run the engine, but you would need to have it programmed out of the 97 PCM to avoid codes.
And you can’t put the 97 timing cover on the 94 unless you also use the 97 Opti, the 97 damper hub (shorter to allow room for the reluctor), the 97 timing set and the 97 cam. If you use the 97 Opti, you have to use the 97 short Opti harness because the harness connectors are different.
You also need to swap the 97 knock sensor to the 94 engine. The 97 PCM will set a code with the 94 knock sensor, and retard the timing.
Then there's the 97 EVAP system vacuum monitor switch on the passenger side that the 97 PCM needs. And the 97 engine harness has a single coil connector, while the 94 engine has a dual connector coil.
This article has photos of the different timing covers:
LT1 Engine - Chevrolet Rebuilding
Shoebox also has a good guide to the differences in all years from 93 through 97.
http://shbox.com/1/4th_gen_f-body_ye...onversions.pdf
To put the 97 reluctor gear on the 94 engine, you would have to change the timing cover to the 97, because the 94 doesn’t have a crank position (CKP) sensor. The 97 only uses the CKP to facilitate the misfire detection required by OBD-2. The CKP is not required to run the engine, but you would need to have it programmed out of the 97 PCM to avoid codes.
And you can’t put the 97 timing cover on the 94 unless you also use the 97 Opti, the 97 damper hub (shorter to allow room for the reluctor), the 97 timing set and the 97 cam. If you use the 97 Opti, you have to use the 97 short Opti harness because the harness connectors are different.
You also need to swap the 97 knock sensor to the 94 engine. The 97 PCM will set a code with the 94 knock sensor, and retard the timing.
Then there's the 97 EVAP system vacuum monitor switch on the passenger side that the 97 PCM needs. And the 97 engine harness has a single coil connector, while the 94 engine has a dual connector coil.
This article has photos of the different timing covers:
LT1 Engine - Chevrolet Rebuilding
Shoebox also has a good guide to the differences in all years from 93 through 97.
http://shbox.com/1/4th_gen_f-body_ye...onversions.pdf
Last edited by Injuneer; 08-15-2018 at 09:27 PM.
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