Exhaust differences - 93/94 vs. 95+? (2 Viewers)

[gorbilax]

I am overdue for an exhaust refresh on my 94 1FZ (US Spec). I don’t have emissions testing. My PAIR is gone and I have my O2 sensors relocated to the exhaust manifolds where the PAIR was. From searching the forum, it seems like most of the difference between the OBD1 spec exhaust and the OBD2 spec exhaust seems to be the number/location of the O2 sensors and number of cats. Since my O2 sensors are already moved, is there any reason I can’t use a 95+ exhaust on my ‘94? Any other considerations in play here where things won’t match up? I don’t particularly care about keeping the cats intact either way since I won’t need to have the truck inspected, I just want to make sure the ECU is getting good data from the O2 sensors.

Edit: my main goal here is to find a bolt on exhaust I can install in the truck myself. I am decent with a wrench but I don’t know how to weld, so fabricating something is probably outside my skill level.

 

[MurderBird45]

Here’s what I used for a downpipe. Bolts right up.

MagnaFlow Direct-Fit Catalytic Converter HM Grade Federal/EPA Compliant 23120 - Stainless Steel Main Piping, 41in Overall Length, Bolt-On Inlet Attachment - Land Cruiser/LX450 HM Replacement Amazon product ASIN B004SH8CR4
As far as cat back, I had a custom stainless steel made. I think Borla is perhaps the only stainless complete kit available. For OEM- the 95 plus system should work, but you’d have to plug the holes for the O2 sensors. Same with the Magnaflow downpipe. Wits End sells a nice plug.

 

[gorbilax]

@MurderBird45 How’s the quality on that magnaflow? I was considering that and I keep reading all the “it’s really a bosal” horror stories. I live in the mid Atlantic and the road salt absolutely destroyed the cheap rock auto bosal exhaust I put on my ranger. Been through two exhausts in six years. Seems to be a “get what you pay for” deal with bosal…

 

[MurderBird45]

Quality has been fine on mine. I heard those stories about the bosal garbage as well, by the one I have was stamped with Magnaflow and I was also able to receive some replacement gaskets from their customer service because they sent the wrong size. I also live in the salt belt and have not noticed any corrosion after the winter.

 

[Dusten]

Here’s what I used for a downpipe. Bolts right up.

MagnaFlow Direct-Fit Catalytic Converter HM Grade Federal/EPA Compliant 23120 - Stainless Steel Main Piping, 41in Overall Length, Bolt-On Inlet Attachment - Land Cruiser/LX450 HM Replacement Amazon product ASIN B004SH8CR4
As far as cat back, I had a custom stainless steel made. I think Borla is perhaps the only stainless complete kit available. For OEM- the 95 plus system should work, but you’d have to plug the holes for the O2 sensors. Same with the Magnaflow downpipe. Wits End sells a nice plug.

Legendex makes a stainless exhaust for the petrol 80 series.

 

[BILT4ME]

I am overdue for an exhaust refresh on my 94 1FZ (US Spec). I don’t have emissions testing. My PAIR is gone and I have my O2 sensors relocated to the exhaust manifolds where the PAIR was. From searching the forum, it seems like most of the difference between the OBD1 spec exhaust and the OBD2 spec exhaust seems to be the number/location of the O2 sensors and number of cats. Since my O2 sensors are already moved, is there any reason I can’t use a 95+ exhaust on my ‘94? Any other considerations in play here where things won’t match up? I don’t particularly care about keeping the cats intact either way since I won’t need to have the truck inspected, I just want to make sure the ECU is getting good data from the O2 sensors.

Edit: my main goal here is to find a bolt on exhaust I can install in the truck myself. I am decent with a wrench but I don’t know how to weld, so fabricating something is probably outside my skill level.

You can install the exhaust from a 95 on your 94, particularly if you have already moved your O2 sensors and deleted the PAIR.

The 94 has dual side x side cats, then routes OVER nthe frame behind the cats.

The 95 routes with dual inline cats and routes UNDER the frame.

The resonator on the last section of pipe should still remain the same (I am not 100% positive on this), but you can do the install. You will have to create or add exhaust hanging brackets to your 94 to match the locations of the 95 exhaust.

There are a couple folks here that have documented doing this with their 94 but have not had a heavily documented change-over.

For Bosal / Magnaflow parts lists and info, see the following thread:

Bosal , your $200 cat-back option

I wanted to put this here for anybody thinking of re-doing there exhaust. When I started this project my exhaust was bad, really bad. It was leaking at the seal between the rear cat and the cat-back. Only one of the exhaust hangers had not rusted off and it was being held by some pipe strap...

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