This won't help exhaust manifold life.............in fact it will be even harder on the exhaust manifolds as greater gas temperature wil be retained inside the manifold.............the turbo or turbos will respond more quickly though the manifolds will fail earlier due to the increased thermal load.

The only long term answer for reliable exhaust manifolds is to utilise the correct material in the first place.

Peter

APS

 

This has been a great, very informative thread. In addition to the longevity concerns cited here, I wish Turbonetics would supply a new manifold so that the cats can be retained. I'm subject to my states emissions program, and it's not feasible for me (as I imagine is the case for many people) to rip my car apart every two years (every 1 year for some guys) to get past emissions testing. I don't consider a kit with this requirement 'streetable'.

Peter, if I may ask you one rather awkward question (and I am in no way being confrontational) can you talk a little about what justifies the higher price tag for the APS kit over the GReddy kit? The GReddy kit is more proven in the market, is reportedly very complete, and many shops are more familiar with it's inner-workings.

I'm very interested in going F/I next summer, so I'd like to be as informed as possible about the various products and there's nobody more qualified to speak about the APS kit than you.

Thanks for your time.

 

Cool Peter, I did want to know what you thought about this issue that I brought up in that post though:

With my engineering degree in my hand, I would still like to understand how the exhaust temperatures are different from an SC to a turbo (a turbo setup like this on where the turbo is not on the manifold). With exhaust flowing through the system of a turbo, it can increase it some, but the main thing that is unclear is with the turbo in the same location as an SC, with both compressing air, is the turbo that much hotter on the exhaust side than the SC to cause this problem with the manifolds?? Also makes you think twice bout turboing if it is so.......as there seems to be no such problems with the manifolds in SC applications and all the extra heat does for an N/A stock engine is wear the engine even more.

 

I think I can help you gain a better understanding since Peter explained the most important part people are missing.
"The turbo exhaust manifolds are subject to much higher thermal loads due to increased exhaust back pressure between the exhaust ports and turbocharger."

Basically on a SC, the headers go out through the exhaust and exit quickly. On a Turbo, the exhaust goes to spool the turbo and then out. This causes a higher back pressure versus your usual CAT and thus higher temperatures. I have to assume the temps are less in this single turbo application versus dual but probably not enough to make the headers reliable.

Feel free to fix any errors Peter.

 

I can see the large increase in backpressure being a factor when the turbo is located so close to the exhaust ports but I still don't understand why that would factor in here considering the placement downstream of the turbo. You are essentially blowing the exhaust into a turbo that is after the headers, cats, and y pipe. Thats a lot of realestate piping wise...

 

I spoke with Brad this morning and he will be on here later to share some very good data. I'm sure it will clear up any questions you guys have on Turbonetics kit. I should add that I applaud Turbonetics for their stance on information. Rather than release data or create expectations before a final answer is available they choose to wait until they firm engineering data before making a response. After talking with Brad today regarding the things that APS brought up I am 115% confident in their kit. I think when you all read Brad's response to this you will be more than satisified. While I do respect APS for sharing their concerns before the community I think that in retrospect they might have let Turbonetics share all their data before assumptions were made. Some of the statements have cast shadows on the Turbonetics kit that I feel were very unwarranted especially after the data I got from Brad today. I have the utmost respect for Peter and his company but to me personally as a consumer I feel that it was very unprofessional to talk so strongly against the design of a competitor in a public forum and under the pretense of helping the entire community. If this was not the intention then let me be the first to apologize about this statement but this is how myself and some others viewed what was said.

 

Well, I think that when a new product is announced without this data people will speculate based on their knowledge, maybe the data should have been released at the same time as the info about the kit to prevent speculation about the effects of the kits on stock parts. I don't blame Peter he just made, what I and others think, were valid points based on his experience.

 

I completely agree he made some valid points. I do not agree that all info is expected to be release when a kit is just announced and not released. Turbonetics is not done with their kit and there is still a lot of data to be given. APS did the same thing. Announced they were making the kit and then gave updates as significant data was available. Turbonetics has done nothing different. However I did not see Forced (Vortech) or Unlimited Tuning on here telling people their percieved flaws of the competitors design. I have no problem with speculation about a potential issue. I do see it as improper to INSIST their will be some sort of significant failure in a competitors kit without the data the company used in making their decision. While I can respect Peter's knowledge of turbo design and his willingness to help the community I do not believe that the wording or insistence of failure used was appropiate. He has already readily said that he is very familiar with Turbonetics and that they know their stuff. Many people who have been in the import world have heard of Turbonetics and Fmax and know their products have always been topnotch. It is therefore in my opinion unreasonable to assume that at some point they did not think of the same issues that were brought up and had valid data to support their decision. It just seemed (Beats dead horse) that for a company to INSIST on the failure of a product that is being produced by a competitor in a thread that prior to it had no mention of that company is unprofessional. If I am wrong in viewing it as such so be it. But many other companies have been flamed for less. I remeber not long ago people jumping all over J Ritt for simply posting valid information about a vendor and even worse for posting in a thread about Wilwood. To me the best thing to do is to point out valid points about the system YOU are producing and leave the HEAVY worded opinions to us the consumer.

 

I think you're getting somewhat confused here on this issue. I am not discussing any product that Turbonectics are producing rather I am simply pointing out that if the the stock nissan manifold or manifols are retained within the turbo application..............the Nissan manifolds will be a problem as the stock manifolds are not designed to cope with the extreme thermal loads from turbocharging.

I have seen this approach (retaining stock exhaust manifolds) utilised in bolt turbo turbo systems for over 25 years in many different countries and in every instance that I've seen the manifolds fail (crack and distort) simply the stock exhaust manifolds are cast in a lower material and can't cope with the constant heat cycling.

Now I have said previously that I have a great deal of respect for Turbonectics and that I know the founder of the business very well and I 'd be the first to say that Turbonectics are a great people...............this discussion however is not about people simply it's about engineering and the stock nissan exhaust manifold reliability when utilised in a turbo application.

If Turbonectics think differently to me on this issue then so be it, I don't think any less of the Turbonectics business or people and Brad is a terrific guy............we'll just agree to disagree on this one issue.

Thanks

Peter

 

Just out of curiosity I talked to Doug at Crawford today about the possibility of having stainless 321 1/8 wall headers made. He said it was a no go. The stainless does not have the ability to be shaped to meet the collector like the steel does that they use on their standard headers. I asked if Burns stainless had anything and he said he had tried to source the stainless parts when they originally started their header R & D.....but with no success from anywhere. Doug suggested the best option would be Jet Hot coated thick wall headers. That's the best he could come up with.
I guess stock manifolds or another aftermarket header are the only way to go with the Turbonetics kit. Hopefully they can put the manifold issue to rest with their engineering data MIAPLAYA had mentioned.

 

Now that sir, is a statement I can respect. I appreciate you explaining that a little more in detail. To me and several others the whole thread seemed a little awkward. Now that all that has past we can get onto the good stuff. Like making boost....

 

Cool.

No doubt it's always awkward when discussing another turbo design approach and it's more awkward when you know the people/business involved...........hey credit where it's due I always respect people who are having a real go and producing a FI product................simply more choices for the Z community.

I really pleased that a decent business like Turbonectics is producing the Big Single turbo system...............this product will be an excellent alternative to centrifugal supercharger system

Hope you enjoy the blast.

Thanks

Peter

 

Oh I will.... Thanks for clarifying. I think you guys make topnotch stuff as well but Turbonetics is more my style... I was pretty happy to hear about their involvement as well. Jahme is really talented and when i found he designed this kit I KNEW it was what I wanted. I have some first hand knowledge of his stuff from SE-Rs and I've always like his work..Now if I could only find that $5k I stashed away....

 

I don't think anything is between the stock manifold and the turbo except piping??? If fact it doesn't have CATs.
I'm interested in Turbonetics response and engineering data on this. Hopefully the temps are low enough since this is a nice option for a lot of people.

 

Would this still be the case if they were coated correctly, i.e inside and out of the manifold?

The heat wouldnt be absorbed by the manifold and it should be sent to the turbo helping it spool quicker.

 

hahaha. i think you got your point across.

 

Ceramic coatings on exhaust manifolds act as insulation to keep the heat inside the exhaust gases, but they do not protect the manifold themselves from the high exhaust tempertures. For instance if a coating where to reflect 95% of the heat back into the exhaust, it would still allow that 5% of the exhaust gas heat to escape into the manifold itself. If there isnt enough air cooling the manifold from the outside, and there isnt much on the 350Z, sooner or later equalibrium of the manifold and the exhaust gas tempertures would be reached. Once the manifolds cool, they have just cycled a prosses of heat expansion and if this process repeats a definate amount of times an exhaust manifold w/ the wrong materials will fail like Peter said.

This is one of the reasons i picked a centrifugal SC. A single turbo setup is just too difficult to implement on the 350Z. Look at HKS, even they discarded a single turbo for a centrifugal SC. They just implemented a system to optimize the SC gearing to give the centrifugal system early boost almost like a single turbo. Im sorry but a good single turbo on the 350Z is just too cost prohibitive IMO. Go TT.

 

Jesus christ, bloody server, thats got to be some record for f'ed up posting.

 

Enron Exec Wrote:
Ceramic coatings on exhaust manifolds act as insulation to keep the heat inside the exhaust gases, but they do not protect the manifold themselves from the high exhaust tempertures. For instance if a coating where to reflect 95% of the heat back into the exhaust, it would still allow that 5% of the exhaust gas heat to escape into the manifold itself. If there isnt enough air cooling the manifold from the outside, and there isnt much on the 350Z, sooner or later equalibrium of the manifold and the exhaust gas tempertures would be reached. Once the manifolds cool, they have just cycled a prosses of heat expansion and if this process repeats a definate amount of times an exhaust manifold w/ the wrong materials will fail like Peter said.

This is one of the reasons i picked a centrifugal SC. A single turbo setup is just too difficult to implement on the 350Z. Look at HKS, even they discarded a single turbo for a centrifugal SC. They just implemented a system to optimize the SC gearing to give the centrifugal system early boost almost like a single turbo. Im sorry but a good single turbo on the 350Z is just too cost prohibitive IMO. Go TT.


Are you saying that even if we reduce the temps by 95%, that the 5% heat will still heat the manifolds all the way up to the 100% level it will just take longer to happen?

I know it is hard to do but people are doing it. Look at TopSecret.

 

Quadruple postage...