F355 Questions about High flow cats. - Ferrari Life
 
LinkBack Thread Tools Display Modes
post #1 of 18 Old 05-13-2014, 03:41 PM Thread Starter
Owner
 
Ready321now's Avatar
 
Join Date: Dec 2012
Ferrari Life Posts: 150
Questions about High flow cats.

Ok, so I anticipate cat failure in the future. Why? Seems to happen all of the time to 355's.

SO...I have my eye on Nouvalari cats. I have Nouvalari manifolds and Sport Exhaust, so I figured maybe just do the cats with Nouvalari.

Here are my questions:
1.Should I expect a new flock of CEL's and SDL's with high flow cats? If so why, and what can I do to avoid this?
2. Will I need to "re-map" the ECU or anything crazy like that?
3. How do high flow cats affect the sound and power?
4. Will there be a gain or a dip anywhere in the RPM range?

Thanks in advance if anyone can answer this for me...
Ready321now is offline  
Sponsored Links
Advertisement
 
post #2 of 18 Old 05-14-2014, 10:00 AM
Owner
 
Join Date: Apr 2013
Location: Floriduh
Ferrari Life Posts: 357
1 No
2 No
3 Yes......greater flow = more power (not massive) and greater sound (cool)
4 not sure about what you are asking.

Bottom Line it is a positive and will sound great

348 spider with Nuvolari exhaust and cat test pipes:

https://www.youtube.com/watch?v=l83S5vRi4Z0

By the way love the color

Last edited by FCBanned4Life; 05-14-2014 at 10:26 AM.
FCBanned4Life is offline  
post #3 of 18 Old 05-14-2014, 11:09 AM Thread Starter
Owner
 
Ready321now's Avatar
 
Join Date: Dec 2012
Ferrari Life Posts: 150
Quote:
Originally Posted by FCBanned4Life View Post
1 No
2 No
3 Yes......greater flow = more power (not massive) and greater sound (cool)
4 not sure about what you are asking.

Bottom Line it is a positive and will sound great

348 spider with Nuvolari exhaust and cat test pipes:

https://www.youtube.com/watch?v=l83S5vRi4Z0

By the way love the color
thanks for the feedback I appreciate it. Question number 4 I basically was wondering if I am going to lose any mid range or bottom end or anything like that? I guess I'm not exactly sure how high flow cats effect the RPM range as far as power is concerned...some Systems seem to scoop power out of the midrange and put it on the top of the RPM range. This might be due to the header configuration rather than the cats though. overall I am expecting to gain power just not sure where
Ready321now is offline  
 
post #4 of 18 Old 05-14-2014, 04:54 PM
Owner
 
Join Date: Apr 2013
Location: Floriduh
Ferrari Life Posts: 357
All you will do is gain...nothing to worry about.
FCBanned4Life is offline  
post #5 of 18 Old 05-15-2014, 01:15 PM
 
Join Date: Jan 2014
Ferrari Life Posts: 24
I just went through this entire exercise with a 348. I pondered and researched. I asked questions and in the end I was making a mountain from a mole hill. Paul is the man. He knows. I don't think one has to have named high flows. I bought mine on E-Bay for 400. new and they work great. I did a reset on my ECU and drove off. There is a noticable drow of engine room tempature. That is good. Andy
awilson is offline  
post #6 of 18 Old 05-15-2014, 03:01 PM
Owner
 
Join Date: Apr 2013
Location: Floriduh
Ferrari Life Posts: 357
The ecu's will learn changes and adjust as long as they are not to radical, simply disconnecting battery and then reconnecting will force an immediate relearn but really not require...just forces the issue. That's the whole ideal of exhaust gas monitoring (o2 sensors) is that it is always happening and feeding that data to ECU's to adjust to changing conditions. The 355 went to pre and post cat o2 sensors with 5.2 bosch system in 96 (OBD2) in 95 they used 2.7 as did late 348's with just post cat o2's.(OBD1).
FCBanned4Life is offline  
post #7 of 18 Old 05-18-2014, 11:16 AM Thread Starter
Owner
 
Ready321now's Avatar
 
Join Date: Dec 2012
Ferrari Life Posts: 150
Good info, thank you. My present cel and SDL seem to be connected to cat temp and bypass valve. I have not been able to figure out why. My bypass valve seems like and sounds like it works just fine. Perhaps new catalytic converters would make the other code go away
Ready321now is offline  
post #8 of 18 Old 05-18-2014, 01:01 PM
Owner
 
Join Date: Apr 2013
Location: Floriduh
Ferrari Life Posts: 357
Quote:
Originally Posted by Ready321now View Post
Good info, thank you. My present cel and SDL seem to be connected to cat temp and bypass valve. I have not been able to figure out why. My bypass valve seems like and sounds like it works just fine. Perhaps new catalytic converters would make the other code go away
The SDL sensor ecu's are notoriously known to send false alerts and those ecu's cost about $400 each if my memory serves me correctly. I unplugged mine (348) before I got rid of cats as they would trip and shut down one cylinder bank or the other for no reason and a few minutes or an hour later the bank would kick back in. The best solution in a state without emissions testing is just to go cat bypass pipes, otherwise highflow cats are the way to go.
FCBanned4Life is offline  
post #9 of 18 Old 12-21-2014, 01:47 PM
Owner
 
Taz355's Avatar
 
Join Date: Mar 2013
Location: Alberta,california
Ferrari Life Posts: 379
Quote:
Originally Posted by Ready321now View Post
Good info, thank you. My present cel and SDL seem to be connected to cat temp and bypass valve. I have not been able to figure out why. My bypass valve seems like and sounds like it works just fine. Perhaps new catalytic converters would make the other code go away
Could be many diff issues. If working correctly you wont get any lights other than a check engine maybe every 3 to 6 months. And even then sometimes its from other systems. I have a 355 99 with tubi headers, previously factory, cappi twin valve and hyperflows. No check engine lights and california 2013 compliant.
Sometimes its thermocouples, sometimes its o2. Sensors, so,etimes its connections, and in my case its always the secondary air pump circuit about once. Per year now.

It can be frustrating but it will work when setup properly and all components are working.

Last edited by Taz355; 12-21-2014 at 11:37 PM.
Taz355 is offline  
post #10 of 18 Old 12-21-2014, 11:25 PM
Owner
 
Join Date: Mar 2012
Ferrari Life Posts: 138
Ditching the temperature ECUs (sdu) for the aerospace logic unit was the best bang for my money. They send the right voltage to the ECU and eliminate the random SDL problemI had in a permanent way,plus give me actual exhaust temps.
Markp is offline  
post #11 of 18 Old 12-21-2014, 11:40 PM
Owner
 
Taz355's Avatar
 
Join Date: Mar 2013
Location: Alberta,california
Ferrari Life Posts: 379
I guess thats one way to handle it. For me in california i needed to replace my cats so i went with hyperflows. The system was always working so i just make sure it keeps working.
Taz355 is offline  
post #12 of 18 Old 01-09-2015, 01:30 PM
 
Join Date: Jan 2015
Ferrari Life Posts: 156
I have hyper-flows and love them. I went to a test pipe style and it sounded like a Hondararri. I had my hyper-flows rebuilt and I'm putting them back on. I never had a CEL with the Hyper-flows but did with the other ones... I had to run O2 extenders. I still have them if you need them
shootfighter65 is offline  
post #13 of 18 Old 01-09-2015, 10:50 PM
Owner
 
Taz355's Avatar
 
Join Date: Mar 2013
Location: Alberta,california
Ferrari Life Posts: 379
Your rebuilding yoir hyperflows??
My understanding is they were good for life
Taz355 is offline  
post #14 of 18 Old 01-10-2015, 07:59 AM
 
Join Date: Jan 2015
Ferrari Life Posts: 156
Quote:
Originally Posted by Taz355 View Post
Your rebuilding yoir hyperflows??
My understanding is they were good for life
I don't think anything is good for life..When I took them off one was rattling so I had to send them out. They came back looking amazing...I think the warranted for 2 years.
shootfighter65 is offline  
post #15 of 18 Old 01-10-2015, 08:22 AM
Owner
 
silly's Avatar
 
Join Date: Feb 2012
Location: SoCal
Ferrari Life Posts: 269
Quote:
Originally Posted by Markp View Post
Ditching the temperature ECUs (sdu) for the aerospace logic unit was the best bang for my money. They send the right voltage to the ECU and eliminate the random SDL problemI had in a permanent way,plus give me actual exhaust temps.
What unit did you use?

94 F348 Challenge
95 F355 Challenge x 2
97 F355 Spider
silly is offline  
post #16 of 18 Old 01-10-2015, 09:37 AM
Master Mechanic
 
ECSofVirginia's Avatar
 
Join Date: Dec 2009
Location: Austin, TX
Ferrari Life Posts: 1,219
I have only ever used the Hyperflow cats on Ferraris, so I can't speak for the Nuvolaris. If the cat core is spec'd correctly, you will not get SDL's or CEL's. You will probably gain 10HP or so. Engine bay temps should decrease slightly too. You won't experience any dips anywhere with proper cats. The reduction in backpressure will improve HP/TQ across the whole range.


A tune is not "necessary" in most cases. However, it is ideal to have the AFR's checked and verified on chassis dyno and have the ECU tuned accordingly if adjustments are needed. I will say that you stand to improve the longevity of the high flow cats by having the ECU's tuned. These cars run very rich maps, particularly @ WOT and the excess in raw fuel will accelerate cat core degradation. If you have the ECU tuned and the AFR leaned out slightly for maximum HP/TQ, there will be less excessive fuel running through the exhaust, thus increasing the cat cores life span.


ECSofVirginia is offline  
post #17 of 18 Old 01-10-2015, 11:29 AM
Owner
 
Taz355's Avatar
 
Join Date: Mar 2013
Location: Alberta,california
Ferrari Life Posts: 379
This was reprinted from hyperflows site



Since all catalytic converters must meet standards established by the Environmental Protection Agency, (EPA) their efficiency in controlling pollutants is a given - provided a particular converter is installed on the type of vehicle for which it was designed. Longevity is also comparable from brand to brand because EPA mandates require the converter case to be warranted for 50,000 miles and the bricks for 25,000 miles. That leaves flow - and horsepower - as the only major characteristic that varies to a considerable degree.


(Reprinted from TURBO & HIGH TECH Magazine.)
Taz355 is offline  
post #18 of 18 Old 01-10-2015, 02:30 PM
 
Join Date: Jan 2015
Ferrari Life Posts: 156
Quote:
Originally Posted by awilson View Post
I just went through this entire exercise with a 348. I pondered and researched. I asked questions and in the end I was making a mountain from a mole hill. Paul is the man. He knows. I don't think one has to have named high flows. I bought mine on E-Bay for 400. new and they work great. I did a reset on my ECU and drove off. There is a noticable drow of engine room tempature. That is good. Andy
Real cats for $400? Or the cheap Chinese test pipes with an outer shell that looks like a cat ? I think materials to build an actual cat is close to $400. I had those or a version and it ruined the sound of my 355
shootfighter65 is offline  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
Copyright 2012 ONE Media, Inc.
FerrariLife is independently run with no affiliation with Ferrari SpA
Ferrari for Sale | Maserati for Sale