Hi! My name is Jim, I live in the Albany area of NY. I used to own an 89 2.8 RS, put wayyyyyy too much money into it, and sold it last summer for 3500 bucks (major bummer). I just scooped up a 91 3.1 RS, and I'm looking to do it all over again. I do have a few questions about performance upgrades for the 3.1 and I figured I would just get it all out in 1 thread.

I plan on buying a hooker cat-back system and a high-flow cat.

I have heard about PaceSetter headers for the 2.8's. Will they fit on the 3.1? What kind of modification is required if I can make them fit?

With the EGR system removed, will the motor still run normally with no check engine lights?

I want to purchase and off-road Y-Pipe. If it does not have an opening for the O2 sensor... Does the oxygen sensor simply monitor emissions or does it control air/fuel ratio? Will it effect how my motor runs if it is removed?

Is it even worth spending money on the V6, or should I just do a motor swap? I have a 350 for the car, but I will need trans, rear driveshaft, ignition system, torque converter, etc, etc, etc.

My original plans for my 89 was to do a swap, so I bought everything thinking there would be a SB in there at one point. The only performance parts I had on the 89 were K&N filters (that I got for free) and cat back exaust (because I knew I could use it when i did a swap

 

As I understand it, any GM engine that utilizes an EGR system AND has an ECM/PCM will watch for a MAP/MAF change when the EGR system is activated. If this change does not occur, then it will throw a Code 32. You'd have to disable the EGR in the PROM. Check out: http://www.tunercat.com/tnr_desc/tnr_desc.html for tuning software.

It is a necessity to place an O2 sensor in the loop if you're running anything other than a carb or you'll get REALLY bad performance. The O2 sensor is the primary feedback sensor that the ECM looks at to regulate the Air/Fuel mix. You can buy from Summit an O2 sensor bung that will weld onto any exhaust pipe to allow the fitting of an O2 sensor. Check here: http://store.summitracing.com/defaul...=egnsearch.asp

It's not the easiest swap unless you understand the engine management system. The best way (in my opinion) to do a swap is to get a Painless engine harness that converts one engine to the other. This also has the added benefit of possibly fixing any age-related problems in the wiring that our older cars may have. When I do my 383 swap, I'm gonna replace the entire harness just for peace of mind because my 14 year old wiring is showing the first signs of its age...and I think most people on this board will agree that it's a GREAT idea to go for the extra cubes of the V8.

 

When I do the swap, it's going to be carbbed, I have done 2 TPI to Carbbed motor swaps in 3rd ges already, but never a V6 to carb swap. My problem is I'm not sure if I want it to be a race car, show car, or street car, or a combination of all of them. The motor I have was dynoed at 537hp and 562 ft lbs torque. If I decide to pull it from the chevelle and swing it into the camaro, I''m goin to need chassis work, and a totally new drivetrain.

On the other hand, I could keep the 3.1, and have another "all show, no go" car. maybe i'll just slap a crate 350 in the thing and call it a day... I guess we'll see when we ge there. For now, I have to do and endless amount of grinding, sanding, priming, and bondo. That will keep my occupied for a while.

 

pacesetter will bolt right in your car, no problem...even with the 3.1. the only thing is that they are only smog legal for the 2.8s. if they run the CARB number off of the headers at a smog inspection...they will catch that. physically, they fit the same, though.

removing the EGR will throw a code 32 but will not hurt anything. you can have that code disabled on your computer chip, if you want.

Y-pipe is included with the pacesetters. o2 sensor is a must!

These V6s can make decent power if you're willing to spend a little money on them and put a little time in them. no, its not going to be a real beast of a motor but you can make decent power with it.

 

If you are going to install an off-road "test pipe" as they call it, DO NOT plan on welding it in place if you plan on keeping the car legal, unless you know of a garage willing to overlook it. My car originally had one installed and I was forced to cut it off (it was welded in) because my shop told me I had to have a convertor to pass NYS inspection. However, they didn't say I couldn't gut the cat, which I have done...

:edit: I think I misread the first post... However, the same still holds true. Now, when I replaced my pipes (the y-pipe was literally broken in half by the previous owner and welded together rather badly and Ihe also cut the flange off of the intermediate pipe so I couldn't properly install the cat), I had originally bought a pipe from the J/Y that did not have any provisions for an oxygen sensor, probably from an older carbed 2.8, and did not notice any real problems with mileage or any codes. However, I did replace that pipe with a different one that has the 02 provision because there is a slight difference in diameter between the two pipes, with the carbed pipe being smaller in diameter.

 

Well there's no difference between these cars and any other non-v8 car for a v6-to-v8 swap if you're going non-computer, except for:

1. V6 radiator is too thin compared to a v8 rad
2. V6 front springs should be swapped for v8 front springs
3. Trans won't fit up to a v8, need to swap the trans too

What's nice is-

1. Driveshaft is "v8" strength
2. Rear axle is "v8" strength
3. Rest of suspension (other than front springs) is OK
4. Brakes are the same as V8s (you might want to upgrade tho)

And you'd probably want to add subframe connectors from either Spohn (one of our sponsor link graphics at the top of this page) or TDS (another sponsor, sells Alston connectors) to eliminate body twist.

 

A guy I know was telling me a story from years ago where he had a muscle car running straight pipes that also had a relatively clean exhaust. He had to pass a visual inspection so he went to a junkyard and grabbed one used cat. He split it own the side welds and then tackwelded one half to the bottom of each exhaust pipe. If you got down on your knees to take a look, you'd surely see that it wasn't a real cat, but when the emissions people look quickly with their little mirror...they'd never know...