Test Pipes or Highspeed Cats on 1990 348?

Greetings All,

Me again! (lol) On my last two Ferraris, 1985 308, and a 1986 328 the first thing I did was remove the Cats. They both sounded great and ran fantastic! Now on my new 1990 348 we have two Cats! I have heard from several Ferrari experts, and Ferrari club folks that say don't put on test-pipes as you will have OBD 2 Issues, poor performance, and warning lights! Their suggestion was to put on Highspeed performance cats. (Fab-Speed) Please advise as to what should I do. I think getting rid of the cats the engine will run much cooler, and better. Please let me know your thoughts
here.

Again,
thank you for your help

 

Considering your car is OBD1, hopefully that provides your answer

 

I had no issues with test pipes....91 2.7. I certainly didnt have any OBD2 problems....

 

I ran 200 cell metal core cats on my ‘90 when I owned it.

On another car site someone did a dyno test of straight pipes vs 200 cell cats = a negligible 1/hp difference.

I hate the way raw exhaust smells, since there is basically no difference power I ran highflow cats. Plus you will be hard pressed to tell the difference in sound between the two. Also when I had to take it for emissions testing it passed easily.

 

High flow all the way. It’s not the 60s anymore.

 

I've had straight test pipes on my 1990 348 Challenge (along with the Challenge 'muffler' that's really not much of a muffler!), and the car runs like a top with zero issues.

That being said, I have a pair of brand new, unused high flow cats I might be selling if you decide to go that route. DM me if you're interested

 

Wow this is great advice! So, what I am hearing is if I put on test pipes, I will not have any OBD-1 issues, or performance issues, or warning lights? The car will be fine? Ok I see test pipes from FabSpeed that have places to screw in these Sencer wires, to match the ones on the cats. Once this is done that's it? No issues?
Just cat free great engine performance?

 

Yup!

 

no issues at all with test pipes on a 95 f355...and with headers and muffler it will sound insane

 

The warning lights are for cat temps and since you don't have them, there you go. The question is if you are going to run the O2 sensors or not. Personally, I would just install the free flowing cats along with headers and a single can free flowing muffler.

 

I don't know about 348, but I've had both on my 355 and I prefer the cats. The test pipes sound better, but the smell is just too much.

 

How can you not run the o2 sensors?

 

I think he could be referring to the second O2 sensor, after the cat? Since all 348s are OBD1 there is no secondary O2 sensor = no.
On ODB2 cars I do know that you can get a tune to ignore the second O2 sensor, or raise the valves so high that is should not trigger a light. For track use only of course.

 

But there is only one 02 per side on 348 right?

 

Correct, both pre-cat.

 

Doesnt the ecu need the pre cat o2 sensor to determine fueling?

 

You are right, neither the pre-CAT (fuel mixture monitor) nor, where used, the post-CAT (CAT health monitor) O2 sensors can be removed without some fairly serious reprogramming of the ECU.

 

Yes it does. The pre-cat O2 sensors stay.

 

Yeah, you need the pre-cat sensors, but I have heard that on OBD II cars, the after-cat pair not so. So, on a 348 yeah you got to leave them in. Sorry for the confusion.

 

This, I also removed the test pipes on my 355 for metallic core cats (top speed pro 1), not a fan of the exhaust smell at idle with the test pipes. They were a bit of a pita to fit but make a big difference when warming the car up. I still have the test pipes but they'll likely sit on the shelf next to the original cats and collect dust.