Ohh Snap! On a more technical note, I've noticed that this product has been developed off the results of testing on a Stagea, which to my knowledge came with the RB25DET, and in the Autech models a RB26DETT. I'm guessing it was for the former, so a single turbo setup. Would it be logical to assume that the wastegate gasses (velocities, temperatures, volumes etc) on a single turbo I6 would be completely different from a twin turbo V6 with similar sized turbos? Anyone at uni got some spare time to do a quick CFD of both types of dumps? Your thoughts Greg? I'm not convinced that the pricing is a true reflection of the end product, as far as I can see you have split a fancy mandrel bent elbow and tacked in some filler pieces, you make more than 10 at a time and the price would be likely cut by a half with suitabe jigs. Stainless tube aint that expensive (yes I work with it every day). Big thumbs up for the R&D though (mainly D, but the R will be coming soon enough )
I think the Street Machine Issues were October and November 2003 (I can't find a link to them) and yes back then there were only 22 different brands and styles of extractors to suit the Gen 3 Commodore that were made in Australia. Of course now, there are many more available. And yes, he tested all 22 types/brands. The articles took up around 10 pages in each of the 2 issues of Street Machine. Sam's Performance has gone from working on all types of cars - mainly V8, to almost exclusively working on Gen 3's, Gen 4's, etc. ie no earlier model Commodores, no Fords, no V6's, and no carbi's (he was a carbi expert as well) etc and he is flat out.... It just shows you how much the 300zx is the poor cousin. ie no Australian made extractors or turbo manifolds, & no testing etc. This is the type of Dump Pipe that was the "Ducks Guts" 18 months ago. If you look at how the pipes have to be cut along the length and the tig welding that goes into them, you can see why they are expensive. Different size pipes and also different angles welded together. The volume of this pipe is also much greater than a Bellmouth These are the split dump pipes off the DriftZ. Unfortunately the engine was not reliable enough, or in the car long enough, to do any testing with and without protruding dividers into the turbo, bellmouths, etc. I can't find ours to measure them at the moment, but the first 15 - 25mm may have been smaller than 3" to allow for the bolts to be accessed and fit the turbo, but from then on it was a 3" pipe plus and 1-3/4" pipe. These were also quick 1 off pipes. The flange plates were also 16mm thick and oversized to prevent warpage and leakages. The bellmouth design is split into 2 parts and from the measurements posted above, the wastegate has a bigger opening than the turbo. The extra size on the bellmouth is only for the first few inches (half of which is reduced because of the divider) and then it becomes a single 3" pipe. The split dump is 3" + 1-3/4" for the first 500mm at which time the exhaust gasses have had a chance to expand and contract. As I said previously, we haven't done any back to back testing, but we are also not professing to be experts on 300zx and saying one is better than another. We would not do this without back to back dyno testing.
Rob, I am not a 300zx expert, and even though we have worked on lots of Zeds, this is not our main target market. We work on all types of car exhausts, but we target V8 VT onwards Commodores (NA, single turbo, twin turbo, supercharged, NOS, etc). We have all sorts of dyno sheets, video clips, etc for all types of combinations on these cars - because they are our target market. We are also sponsors on the LS1 forum, we advertise in the Street Commodores magazine and our website is targeted at Gen 3's. However, if we were to develop a product, we would try the different combinations and dyno test them before we released them, or said that one was better than the other. Have a look at the VE page on our website. We spent 3 weeks of testing different combinations on the one car, getting the performance, sound and no drone. This brand new car had more dyno km's than it had road km's. Who paid for this??? We did, as this is our target market. UAS asked me 18 months ago to make the 3 designs on the one car, do back to back dyno testing, make an extra set of the winning design, make jigs, and then supply them to him exclusively. Who did he want to pay for all this work and testing? Us! 18 months later, he is saying the bellmouth is the best performing design over all the other types, but he has not tested or made any of them to come up with that conclusion. John may be right !!! but who knows??? If anyone made statements like that on the LS1 forum without dyno proof they would get shot down in flames. LS1's are different animals. There are probably 20 LS1 experts in every major City and most have their own dynos, whereas there are probably only 5-10 300zx specialists in the whole country. This has nothing to do with my past problems, and I am not having a cheap shot, I am just making a comparison. Have a look at the LS1 Community and you will know that you are not being looked after as much as you think you are. If a business derives its income and stakes its reputation on a type of car, they have to do the testing that goes along with it to stay on top of there game. Lets face it, when it comes to a 300zx TT there are more workshops that will turn you away than are prepared to work on it, and some of the ones that do accept the work, really shouldn't. Workshops that do work on 300zx, can and do, charge a lot more for the work they do on them. How can you make claims about a product that was tested on a different car, different engine, single turbo instead of twin turbo, etc and claim that it is better than other designs that you have not had made or tested? In his opinion bellmouth. . . ., in my opinion split dump pipe . . . ., someone else's opinion is an expansion type . . . . , etc. Everyone has opinions. Opinions are like a$$holes - everyone has one, and most stink !!! All I am saying is there needs to be proper testing done before outlandish claims are made. And I am not talking about testing a 3" dump against a 2.5" dump, or a short dump. I am talking about apples with apples - ie all 3" long dumps that go all the way to the cats. This will only benefit the forum members and will be good technical reading. Once this is done, then you can make all the claims you like - as you have the proof. I am not singling out UAS. This was an exhaust thread and was of interest to me. It would not have mattered who was making or selling the product, I still would have made similar comments. Any product that claims performance gains should be accompanied with proof, this is what helps to sort out the fact from the BS. Cheers Greg
Is it just me or has this thread turned into a big pissing match. Yes it started off factual but seems to have gone off on a topic tangient and the VG30 is being compared to holden V8's now I have been fortunate enough to have been around while most of this was happening and know the history with the DriftZ and UAS aswell so feel somewhat qualified to enter a response here. For starters most people who have had extensive dealings with JP will realise he is a pretty straight shooter when he stays focused enough on the topic at hand lol, having said that he has been in the business a long time and has got to see first hand what works on a varied range of cars not just 300zx's. Overall design has more to do with flow calculations, pressure drops, temperature drops and generally getting something to fit in the already cramped Z32 engine bay. I personally think a full divorced flange setup with wastegate gases vented straight to atmosphere via external gates is the best but not road legal and trying to get that to fit is hard, so there are compromises as there are with all designs. At the end of the day whomever produces them need to make sure that A - they dont actually hurt performance B - They fit and dont rub anything anywhere C - Are competitively priced to be attractive to the market and actually sell To compare the VG30 to Gen 3 is crazy IMHO they are two totally different engines, totally different cars and access is alot less restricted in a commy. Even with experts doing it I think it would take a good full day to pull a zed engine remove and refit dumps and exhaust then dyno test etc. It could be done but as Greg mentioned someone has to foot the bill for that R&D and then it will be passed onto the consumer. The market for that type of thing in Australia is really small most simply cannot afford to spend 4k on a turbo kit then another 1k or more on dumps to suit so to get a product that works and is cheap takes a little more thought for the Z32 than for the commy. I think that is where UAS thoughts are. They have taken info based on another car with similar turbochargers and are now trying to adapt what they have learnt to the Z32 and VG30 which I think is great. If it works and they are cheap they will sell. If they made up 3 or 4 different sets tested them all and spent two weeks doing it ($100 x 8hours for 2 guys over two weeks plus materials and dyno time) its big bucks and is probably the reason both UAS and Sureflow decided not to pursue anything like that 18 months ago. Playing the blame game between each other is just childish. From a business point of view testing on that scale for such a small market is false economy in my view. If this bellmouth setup works out we (as consumers) will have a varied choice of setups to go for and it will be up to the individual to choose what they want based on there preference and how deep there pockets are. As far as dyno sheets go well I dont think we will ever get a true back to back comparison even if full scale testing is carried out variance in the dyno and temps etc can see wildly different readings at the treads and may be so small a difference it may not even be noticeable. Well thats the end of my rant
That covers it Well put and pretty well covered Jason. The main problem is there are not many buyers for this type of exhaust to cover the costs of doing back to back tests, which as you know takes time for even simple things. Unlike the huge Commy market. We will do the test on my car, apples for apples. In the short term I am happy to supply some of our bell mouth type if someone wants to test. If we do it will be independent as always, as my staff or I don't fudge things and we sell both types and simply looking for the best overall for flow, weight, fitment, and ground clearance. Interesting Dyno testing is ideal but not viable on all products and many products including Nismo dumps are bolted up to cars everyday with no dyno testing or results. I know our design in theory makes sense and as mentioned earlier this is exactly how Nismo make dumps for GTR's. HKS make separate pipes though. Both could be right for stock turbos although could well be different for larger turbo's. It is like the debate on front mount intercoolers over large corner mounts. We sell both and argued until the cows came home that front mount was clearly better. I explained why technically, physically etc and got all sorts of contrary with stats from USA dyno comparisons etc. We finally spent best part of a day testing it and proved it. The subsequent UAS designed intercoolers we sold, did not make up for the cost of doing these tests, not even close. With intercoolers and heat soak it was important to do back to back to back tests otherwise you get false results. Yes Thunder that is the best design dump as has best of both theories. That pic is from our site, link below, it is HKS GT2835 Pro for Skylines. I don't think there is enough room in tight engine bay to make like this though. Also you might check those pipes as I know there is not enough room to have a 3 inch pipe, and a separate pipe anywhere near the flange for the turbo. The pic you put up shows this. It flares up to 3 inch after the right angle or might be a 45 that comes off the flange to the turbo. The separate pipe is probably not 1/2 a metre either. I am at home and can't check but anyway the more critical requirement is exiting the turbo into a largest area, where it is the fastest and hottest and wants to expand and free flow, and why the much larger opening of a full ID of flange bell mouth type should be slightly better than shooting into two pipes, although mainly with larger turbo's. Also 16mm flanges, are you sure? If so that is huge heavy thick things and not needed. We have never had a prob with 10mm flanges including our race car, better than being too thin I guess but. http://gtr.com.au/pricelists/pricelist_skylineturbos.htm By the way we were a bit shocked to find rough jaggered edges on the inside of these HKS dumps, where the pipes re join. We used our die grinder with the extra long bur to grind this smoother and reduce turbulence for the customer prior to fitting.
