355 Fabspeed Headers

When I spoke with DH about the header issue, he stated to me that OEM's are by far the best. His statement was made based on contruction and flow. He's not a fan of the aftermarket ones, at least that's what was said in our conversation.

At that time, to my knowledge, his statements has no bearing on any new improved design. If they did, he did not say that.

Remember, DH believes the header failures are related to excess fuel getting burned off in the headers via poor electrical connections and the ECU getting poor info and responding poorly...

 

For small displacement V8's a tri-Y design has proven countless times in the record books to give a better power band for road racing. For drag racing 4 into 1 will produce more power for the drags. Tri-Y will give you better milage also. Decades of R&D have proven this.

 

Thanks Dave, that is what I thought based on reading header threads in the past. I had mine constructed based on the experience of this group and what they believed to be a proper header solution. Keep OEM design(4-2-1), improve the s/s used, and keep the heat shields.

If I am one of the skeptical ones it is only because the vendor that I spoke with about these never mentioned that these were improved oem headers or answered my questions about their construction. I don't want to beat a dead horse, but I spent a lot of time doing research with just about every vendor out there that makes 355 headers. Getting specifications on the s/s used, tube thickness, design, and primary tube diameter, and type of bends used. I also contacted 5 custom header builders.

 

Well stated Tim. The 355 doesn't have a lot of torque, so it needs all the help it can get.

 

When NTSA has a safety recall they can point to specific issues and show a specific faulty part that fails near universally in the product. Anyone ever owned a chrysler product? Once I had a jeep. 2 things always failed middle exhaust hanger and washer bottle. Go to parts counter and ask for either of thee parts and the guy reaches under the counter and produces them. That is how fast and often they fail. What we have with 355 valve guides and headers is random failures throughout the entire model run at a level higher than Ferrari normal and the same meltdown of headers or guides on other ferrari models very randomly and wuth lower frequency than the 355. That fact, by itself validates something happening like DH theorizes. There is no denying some contribution by poor header material choice or valve guide composition choice where "all" operating parameters where not accounted for. But what if DH is right and people got their 355's to stay in a small operational (ideal) range would the headers and guides stay together? We could get some real clues to what is really going on with a well designed poll.

 

I have Fabspeed headers with a Nouvalari Supersport exhaust and I've never heard a car sound better than mine except for the ones equipped with a Capristo 3.

 

Mille Miglia on mine, sounds like a million bucks.

 

As far as the stock header design being best = BS in my opinion.

The 348 and 355 share the same stock header design. They are both tri-y's, and they both have the primaries nonsequetially paired. With the difference being the 355 headers have the exhaust bypass in the second collector, and the 348 does not. The nonsequential pairing has the primary collector "seeing" the exhaust pulses every 360°. The primaries on both the 348 and 355 are short, and the secondaries are REALLY short. At the higher rpms this may be okay because the harmonic frequencies will be such that they will help in cylinder scavenging, and help peak hp. But from what I have seen that only helps the torque at the lower midrange, higher midrange, and for a short power band, 3500-4250/rpm and 5500-6000/rpm. The primaries are so short that it's the secondary collector that sees the pulses most of the time, all the pulses from all the primaries. So in my opinion what's the point of even having a tri-y/4-2-1 design if it's only gonna be good for two small 500-750/rpm windows?

I have a custom set of headers that are still tri-y, but follow a different philosophy. The primaries are paired sequentially, meaning the primary collector sees the exhaust pulses every 180° of crank rotation. My primaries and secondaries are both much longer than the stock design, and are stepped. The longer length helps keep the exhaust speed up, and the stepping helps reduce restriction at higher rpms. Did a comparison dyno of stock headers, stock cats, and stock single can muffler VS my custom headers, free flow cats, and custom muffler. The result was bottom end torque between the two headers 2275-4200 was the same. At 4200 my custom headers took off and never looked back. They made more torque all the way to the rev limiter. Peak torque was only 4.7lbft more @ 6000/rpm but under the curve is where they REALLY shined. While the stock headers had started to dip at 4300 bottomed at 5000 then peaked at 6000, my custom headers made 12.6-lbft more torque, and had a MUCH better torque band from 4200-5600, and never lost torque to the stock tri-y design all the way out to 7750/rpm. Having said that, both torque curves simply DIED over 7000/rpm, but I think that has more to do with the stock cam design.

Then there are dyno graphs of Fabspeeds headers making more power than the stock headers.

So that is why I call BS on the stock header design being "best". I have done the dyno testing on my car, and have seen the dynos of other cars, which proves that is simply NOT the truth. The ONLY "person's" word I believe on this matter is what the DYNO says.

Stock suck!

 

That is all very interesting Ernie

My car will never see a track or a Dyno. It runs great and had more than enough power for me just the way it is. Sounds great, looks great , runs great. Couldn't be better.

OEM Ferrari headers rule!!

😜

 

LOL! I call BS on your BS. I was at that dyno day. Your giant sample size defeat of 3 other 348's each with different modifications/configurations for very small gains is not an impressive endorsement for your position. I saw the graphs. You don't even have big enough difference to definitively draw conclusions for 348's.
A 355 is not a 348. Ever watch the movie twins?
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Never tought I'd see the day someone say that on Fchat...

How about another first:

Ferrari interior plastic black coating rules!

 

Serious question. How many people have seen good picture of the stock F355 headers with the the heat shields removed? It is shocking how poorly made they are. I haven't seen stock headers of lower quality on any car I have EVER seen.

From what I have read and seen headers like Fabspeed make more power in the mid range as a 4-1 design than the stock 4-2-1 design just on quality of build alone.

The Fabspeed headers are not perfect, but thinking that the OEM headers are somehow the only good option just shows a lack of understanding of the whole header issue on 355's.

 

My eyes have seen way to many headers....lol
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Yes you where there THAT day. Between three of the modified 348s yeah the power wasn't all that great of a difference, and there were actually five 348's there that day. But you where NOT there a few months later when I when back to dyno test the stock exhaust system. That day Church's did a graph over lay of the stock system vs my dyno for the "dyno day" test that you where present at. Those are the results I'm talking about.

However, since you want 355 vs 355 compairison here's one for you to chew on. Gothspeed had his 5.2 355 dyno'd at Church's and he put down 367hp to the hubs. The Dynapack dyno at Church's only has an -8% loss because it's bolted directly to the hubs. Taking that -8% loss into account Ozzy's 355 is making roughly 399hp at the crank. The stock numbers for the 5.2 are 375hp, meaning Ozzy's 355 is making +24hp over stock. And take a WILD guess who headers he was running on that pull?????? FABSPEED's!

So from more dyno results the stock headers, and on a 355 this time , the dyno has stated loud and clear.........stock suck.

Here is a question for you.

How many stock headers have we header of melting? Lots.
How many Fabspeed headers have we heard of melting? ZERO to date.

The build quality of the stock headers sucks. Again why I say stock sucks.

But hey, whatever's clever. If you wanna believe stock is best have at it. I'll believe what the dyno says, and what the UNmelted headers say.

 

Dude...go do some homework on dynos. You can make 24hp just by picking a cool day to run the test. I could pee in front of Church's giant fan blowing on your car and get you more horsepower on the dyno. I really don't care who's headers are better. What I do care about is dissemination of advice with poor data and lacking information.

 

"poor data" and "lacking information", that's a laugh. I have a feeling that even if I where to post up the dyno sheet proving what I say you'll still try and find something to wrong with it. Dude.......quit being a piss ant, and take a chill pill.

I do care about who's headers are better, as do many, many others. Which is why companies like Fabspeed, Capristo, and Tubi have a business selling after market headers for the 355.

 

I also care about which headers are well made. I wouldn't have followed in Bruce's (BCWAWRIGHT) and your path if I didn't want a quality product by having them custom built with 321s/s. If the new OEM headers are supposedly improved someone should be able to provide definitive answers on the improvements. I have not heard that yet.

If Ferrari did upgrade the s/s used to 304 (Tubi and Fabspeed) at the very least and increased the gauge then I would think that these headers would definitely be a good option over some of the others especially at that price point.

If more hp is what you are after, other cars should be considered.

 

I agree with you. Problem is why is 321 or 304 an "upgrade" or proper selection? We have no data. We don't know what Ferrari engineers know. We don't have data for operational parameters or the range of these parameters over the entire fleet. We don't know where the Ferrari bean counters cut corners. We still can't even agree if the the underlying cause for new headers is headers or mixture control or something else. There is too much we don't know and have no data for.

Without these kinds of data and information you can't optimize for the "system." You can take a sledgehammer to the problem and trial and error what works like 304ss and thicker heavier walls but that is like putting a racing harness in your streetcar thinking you have improved the safety. This is kicking the can down the road engineering until the next weak link is found. This is only owning a hammer and all the problem's answer's start looking like nails.

A person or two here think they "know." I don't have those magic powers and I am not arrogant enough to think I know everything either.

 

Your right that we don't know if other issues are causing header failures and I have read posts about this, but I have not read too many posts from owners talking about their Tubi or Fabspeed headers failing even if these other issues exist. Usually people are happy with their aftermarket headers. I am sure that there are some failures as with any product. Quicksilver and JPExhausts just re-tube the primaries and have not had too many failures. Both of these companies upgrade the s/s to 304. You have to start somewhere. Upgrading the material is a good starting place. If you know the product is built well, using good materials with competent people building them and are still having header problems then further investigation is needed.

 

With regards to the Tubi headers, 304s/s, tube thickness is 2mm. 2mm = .0787"

JPExhausts and Quicksilver rebuilt primary pipes are 304s/s and are 1.5mm. 1.5mm = .0590"

16 gauge thickness is .063".

18 gauge thickness is .049".

Older OEM headers are 409s/s, tube thickness is 1.2mm. 1.2mm = .0472"

New OEM. Materials and gauge unknown at the present. Any information on these would be appreciated.

 

Here are a couple pictures for Bruce just to silence the "scam" insinuation on the new parts

They sure look pretty down there and I love that Ferrari logo on them so plainly visible

No need to tear the heat shields off original ones or wonder where they were made.

At this price point they are a valid alternative.

I will write and call some people and see if anyone can provide specifics of design/material changes that were made from 17 years ago.
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Another
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That would be great Bob. If they did upgrade the materials they would be a valid alternative at that price point. The original design seemed to work well. Fabspeeds make more power up on top but there is a dip in power in the midrange. Fabspeed primary tubes are 1.715 or 43.58mm which are up a bit from OEM which are 1.57" or 40mm.

 

Contacted a couple of Ferrari dealers the other day about the new OEM headers. Both dealers heard there were updates but did not know what they were. One of the dealers thought that Ferrari changed vendors.

 

Good of you to do some digging Jimmy. I'm still very happy with my factory Challenge Stradale Headers on my 355 but I understand its not an option for everyone.