Here’s a short vid of Tubi 2.7 355 headers https://www.facebook.com/369043820589076/posts/612609166232539/?vh=e&extid=0
Looks nice! Except anyone that's actually welding thin wall stainless isn't going to stall in the same position for 50 seconds unless they want to overheat/turn grey the last inch of material they welded
I liked everything I read about the Larini exhaust products but I questioned Larini’s response about the 321 upgrade as well. Some welders that I have talked with may or may not weld stainless but if they do, they did not say which grade they would or wouldn’t work with. When I had mine built I had the choice of either 304 or 321. At the time I don’t remember if I asked if they would build them in Inconel, or if it was mentioned I got the impression it would be significantly more expensive. The price to upgrade to 321 from 304 was not significantly more for that upgrade. I think it was a $200-300 increase.
The one thing I do very much like about Inconel besides the weight savings is the way it patinas with a blue hue, while 304 SS tends to look smoked and “old” after about 1,000 miles.
Jimmy, the only difference to the fabricator would be the gauge they are working with. Easier to fab/weld 16ga anything vs 20ga inconel but should really not be any issue to move from 304 to 321 IMO. I would be impressed if anyone could compromise a properly constructed set of 304 stainless F355 headers. 321/inconel Iwould think you told me they are destroyed after the last 5 years of continual track use..
Kline Innovations Inconel Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Here’s a Novitec Inconel shielded set for the 458 Speciale. $20k https://www.vividracing.com/-p-150841317.html?gclid=EAIaIQobChMIqcaUnOK_7AIVERvnCh2W0QopEAQYAiABEgI8xfD_BwE
Larini mentioned they started to offer Inconel shielded products some time this year. I’m having a damn hard time finding any samples of shielded Larini headers for any car. But I did find this... @ttforcefed excited? I am . Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
As soon as I get around to it I'm putting the stock muffler back on. Then maybe I will be able to tolerate, and let's start calling it what it is, that bumble bee sound emanating from the rear of the car. I figure if I keep the revs below 6k I won't get stung. Image Unavailable, Please Login
On a serious note, if Tubi is indeed using aluminum for their shields I think Larini and Tubi are using different approaches to heat shielding. Inconel is a poor conductor of heat compared to aluminum but a factor of 15. On the other hand aluminum has lower emissivity and will radiate less heat. The Larinin headers appear to be wrapped in inconel with the inconel in contact with the header tubes. The poor conductivity would then require a large temperature difference between the inner and outer surfaces of the inconel. Thus the inconel would seem to act similar to a ceramic coating, keeping the heat in the header. The Tubi shields seem to stand off the header tubes. Thus radiation would seem to be the primary means of heat transfer between header tubes and shields. Since the sheild has low emissivity it must have high reflectivity (reflectivity = 1- emissivity). Therefore any heat radiated by the header tubs will be reflected back towards the tubs keeping the heat inside the shields. e by free convection anAs far as heat getting into the engine bay, that would be by free convection and radiation. convection will heat the air circulating in the engine bay which will exit the rear deck (and challenge grill) and isn't the problem with, for example, alternator failure. That is more of a radiation problem. But radiation also depends on the outer surface temperature and the surface area of the shield. We know that the tubi (and OEM) approach, radiation shielding, works. Since Larini headers would seem to compare more the ceramic coated headers, how well do other ceramic coated header work? Make sense to anyone?
I am not a welder, but what you are saying makes perfect sense about the thicker gauge being easier to weld than thinner gauges. So as you mentioned welding one type of material if they are in the same class(304 316 321 vs aluminum vs steel vs Inconel) isn’t as important as the gauge of the material used.
THE METHODOLOGY - Bulky single skin exhaust shielding is used by OEMs to safely 'manage' engine bay temperatures. Larini evolves that application further to aid overall vehicular performance. Larini uses superior, lightweight, ultra-thermally efficient Inconel shielding to protect engine bay components from damage by the massive heat generated by the F355 exhaust line. However, by Dual Shielding, keeping the lightweight inconel shield tight to the exhaust AND double insert-insulating the exhaust component, overall 'performance' now increases too... Keeping the heat within the exhaust by limiting external dissipation as much as possible, means the hotter the internal expelled exhaust gas is - the faster it flows - this is physical law. Faster expulsion of exhaust gasses results in less pressure backing up to the engine, and vitally- increased engine performance. Dual shielding is an overtly complex and labour intensive technology to apply. Yet, Inconel Dual Heat Shielding Technology is the barrier favoured for use in F1 engine component packaging by Manufacturers - obsessed with chasing durability AND outright performance in the thermally volatile demands of the modern Turbo Charged/Hybrid era. Primarily, without doubt, as it is unlikely to fail to perform to an elite level, under prolonged and aggressive heat cycling. (It will not wear away or fall off, being durable enough to endure repeated physical handling and use under the pressure of competition). PLEASE NOTE - The use of heat-safe shielding is used on the stock exhaust manifolds themselves. Due to the internal packaging and critical operating temperatures of the F355, aftermarket unshielded large diameter exhaust manifolds may risk exposing the surrounding engine bay components to 'heat soak' damage. When replacing the manifolds on a F355 - the driver must be sure of the credibility of the aftermarket thermal barrier on the manifolds being used. A paint-based barrier IF not applied correctly, may not suffice as a longterm option in this instance. (Every thermal barrier has its place on the thermal spectrum - but must be rated accordingly and applied correctly, as per thermal requirements - many 2nd tier re-sellers tend to be unable or unaware of this as they rarely work on the project vehicles themselves).
That is great hat they offer it in that material but contradicts one of their previous statements about wanting to stick with the the 316 ss.
Just making my point about OE headers. Here is a shot of another car in for service at Autohaus of Boston posted last Friday. I know nothing about the car, but it still has OE headers. Having owned a Ferrari for 35 years, two for the last 8, I can't help but wonder how much money is spent fixing things that aren't broken,....because they might.