Test Pipes or Hyperflows?

Hyperflows - expensive, emissions compliant, very nice refined sound, no check engine light.

Test Pipes - inexpensive, much louder, check engine light.

You should listen to and take a ride in cars with both set-up's before deciding if possible, hope this helps.

 

when I ran test pipes, there was always a strong smell of exhaust. With Hyperflowss that has smell went away.

 

Hyperflows smell only a bit when cold, then totally disappears, at least on my 95. I don't think I'd want to smell the fumes, and I've read here that there really is no performance gain by using test pipes over Hyperflows.

Change 'em quick, clogged cats are not good for your motor.

 

Not positive, but pretty sure that if they glow red after a good run then they're in rough shape. One thing I've heard from a few mechanics is that if your cats are trashed, you have bigger fish to fry upstream... Meaning there is something bad happening before the exhaust gases make it to the cat, causing the cat to fail. Usually unburnt fuel making it's way into the cat. Don't get all freaked out, I don't really know what I'm talking about!

Maybe a dumb question, but could be a good thing, are you sure you don't already have test pipes? Ferrari cats are huge, not very pretty and unmistakable in the engine bay, right after the headers. Sorry if you know all this... You also may have a small fuel leak or exhaust leak if you indeed have good cats and still get the stink. My car had a few bad valves, a burnt cylinder, and some oil/power steering res leaks and I smelled all kinds of stuff before I sent her to the sick bay. Never really knew what I was smelling, but after the rebuild I don't smell anything except on cold start-up, never while driving.

Hyperflows will sound a lot more growly and mean than stock cats. I drove with both back to back on my nero/tan 95 F355 B that is equipped with Fabspeed headers and Cap 3, and the difference in sound between stock cats vs. Hyperflows was HUGE particularly below 4K rpm in higher gears, though still drastic throughout the driving range. I imagine test pipes would be even more gnarly. Supposedly the Hyperflows flow within a percent or two of most test-pipes, but I could be remembering numbers wrong though I know they're really close. So many threads over the last 6 or so years...

Glad you're having fun with the car. Seriously, if you have stock headers with over 20K miles, change or rebuild 'em!! CV boots also like to let go on these cars. Checking oil is tricky. Your Challenge grille looks great on the red. Don't do burnouts. Parking brake is easily fried, just put it in first and don't let valets drive it. Porterfield 4S brake pads are dope and affordable, with great performance and streetability. Find a great indie that knows the F355. Re-read stuff, because there are so many things to remember about these cars. That's all I have for ya ATM.

Congrats on the car, it looks like a million bucks and you look just as happy in your pics as I was when I first got mine. Four years+ later and I still get the chills. You have great taste by the way, nothing like a 1995 F355 Berlinetta!! The best option for beginning Ferrari lovers who want some scary thrills.

 

Well, it may depend on other parts in the system......

I have Fabspeed headers / hyperflow cats and a Tubi. I get check engine codes 0432 0422 "Cat inefficient" lights due to the higher flow rates.

I can't tell you how off it is as emissions are not tested where I live.

 

Considering the damage you can do with clogged cats, it is worth the effort to look inside.

Pull the bumper, drop the exhaust and take a look at what's in there. Waiting or guessing at this one might get expensive. My crummy 2 cents anyway......

 

I had test pipes on my 348 and it stunk. Clothes, hair, etc. It was a pain. With HyperFlow cats on the car there is no fuel smell whatsoever, and the performance (to me) seems almost identical.

 

No CELs on the 95 cars.

 

I'm also a big fan of the Hyper-Flow setup, I just sold a pair for a gentleman with a F430 the other day. These cats are engineered to the highest standard, you'll get every bit of power that's available with an exhaust mod while having the emissions handled properly. The secondary effect is that because they are better flowing you do get a sweeter exhaust note than stock.

 

my experience:
I have test pipes running to a factory muffler and it sounds great, gives great throttle response and no lights are on. There is also no unpleasnt odor.

 

The choice is very simple. Straight pipes will always have the least resistance and therefor more power. If you have a 2.7 system then the straight pipes is the obvious choice. If you have a 5.2 then some sort of sport cats are the only choice. Remember that if there is no smell then the cats are doing their job so obviously there is going to be some restriction and a small loss of power.

 

Hi Yassa,

Fabspeed makes test pipes and sport cats for the 355. They are both made in the USA from T304 stainless steel and are mirror polished. I have both items in stock. Please email or PM me to see my special Fchat pricing or if you have any questions. Thanks!

Jeff
[email protected]
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I have Larini test pipes on my 355 and wouldn't have it any other way! There is no smell in the car and the sound is awesome. And the tailpipe flames are even cooler!

 

With test pipes when accelerating over 3000 RPM Isn't better to run the car with the bypass valve closed, so the flow goes directly to the test pipes and out the exhaust instead of the y-pipe? Also when you have no CATS isn't leaded gasoline required for the engine?

 

I have Fabspeed headers and the test pipes. I don't get any check engine lights coming on. But mine is the 2.7 version, 1995 Ferrari F355 Spider. I don't have any problems with smells, but it is loud! Love it.

Also a tubi exhaust at the end.

 

Hi Rorie,

Thanks for the feedback! Enjoy!

Jeff

 

Completely normal, the cars run a more rich fuel mixture at idle AND it takes some time for the catalytics to get up to temperature and start working.