I don't know if this is too late, but im trying to organise a group buy for the gt28rs (disco-potatos) from an ebay user. ill have a price soon.
They are too big matey We are only driving them with 1500cc. Check out the earlier link to Z1 motorsports in the general forum about the GT28R. They had to change turbine housings to the same size as the GT28R to get the thing to work at lower revs. But far be it from me to put you off. Its your car. :thumbsup:
Specs Are these the same size as the standard S15 turbo? Someone told me they may be bigger which would give more lag - ie on boost at around 4000rpm instead of around 3500rpm. Can you confirm please. If they are the same, I definitely want a pair.
Re: Specs the A/R is the same as the S15 from wot i can find out. The gt28RS is bigger which is the reason not to use them. I have posted the specs sheet so I think if you do a bit of googling you will find out the definitive answer and then you can tell us all.
Here is the TTzed order link guys http://www.ttzed.com/products/products_detail.cfm?CFID=16283656&CFTOKEN=5&cat=30&grouping=6&grouptitle=Specials&PartID=923&page=1&title=Turbo%20Upgrades&do=detail Please check all the conditions etc. And order away. Please note: the specs are the ones written on the side of the order page. (which is the same as the ones posted by me earlier) The data sheet picture on the TTZ order page isnt correct. Graham
Hey Graham, this might confuse a few people The photo that is on TTzed shows a GT28R with circular rings for the compressor side for both inlet and outlet. But on the first page of this group buy post, you have the photo of the turbo with the 2bolt inlet and 3 bolt outlet. Im hoping the turbo that we are getting in this group buy is the one with the 2/3 bolt setup and not just a circular flange. Could you please confirm which one we are getting. Cheers Michael H
Re: Hey Graham, this might confuse a few people The one we are getting is the one on the page I put up earlier on in this thread. I think Simon uploaded the wrong picture, cause the figures are all wrong in the pic, but right in the text. The picture is the GT28RS disco potato. The one we dont want. Its way more expensibe anyway so we wont be getting that one in any case. I will see him tomorrow and get him to change it. I have to pick up my FMIC
I think I stuffed up the link Sorry guys, See if this one works http://www.ttzed.com/products/products_detail.cfm?CFID=17144689&CFTOKEN=93802087&cat=30&grouping=6&grouptitle=Specials&PartID=923&page=1&title=Turbo%20Upgrades&do=detail If it doesnt. The deal is under "Specials" then "turbo upgrade" Its the only one there.
I might be in, I will let you know soon. I want to make sure my manage can garantee me the hours to cover the costs thats all. If i can get the shifts worked so that im doing enough over the next 6 weeks i will be set.
Re: I might be in, I will let you know soon. Cool, the more the merrier matey. When your ready log onto TTzed and sort your order out. We are all gonna be looking for a dyno day later this year to test our new toys out.
Re: Turbos I am not sure, I am gonna put a thread on the Skyline and Sylvia forums as well. I was talking to Simon today, Including mine, we are up to 4 sets. :thumbsup: I am reassembling the zed at warp speed so its finished by the time these come to us so I can stick them straight in. Cant wait to get the 300KW kick in the back.
I am definetly keen however i just wanted confirmation that these turbos are same as what John (Unique Zed) are running in their zeds, or if i can get confirmation that the garrett gt28r turbos are exactly the same as the nissan oem s15 bb turbo, i know both use the gt28r centre but i was wondering if the nissan housing or any other part of the turbo is different, also the mexico and japan argument, are the garrett turbos in this group buy japanese made/ assembled or is this done in south america? Thanks Jeremy
Re: I am definetly keen however I Just had a look at John's profile. It says he is running GT25RS, This is the disco potato turbo NOT the one we are talking about here. The RS, depending on which one he has. Is actually too big (if he has the AR.8 version) for a stock engine. It allows for boost up to and over 30 psi. So unless you have an engine with forged internals and is heavily worked to run at 30PSI of boost. It isnt the right turbo. Its also way more expensive than these one's by about double. If he has the one with the slightly smaller turbine it would be quite good but as I said its twice the price of the ones in this group buy and to use its potential, you have to boost to 30PSI and over. Our stock engines cant do that. I have no idea what the part number of the S15 Turbo is (I said this earlier in this thread actually) You would have to find out yourself. I have a Z32 not a S15 so I have no clue about this. If you look at the thread in the general forum. I posted the graphs with the curves for using the group buy turbos on a VG30DETT. They look fantastic. I dont know why people keep looking at this in any case as the S15 is a 2 litre engine and the amount of exhaust gas is 25% greater than half a VG30 at 1.5 litres. There is no direct comparision that can be made in any case. These group buy turbos (according to the graphs) would actually appear to work better on a 2 litre engine like a SR20DET, But they will work fine on half a VG30. Lastly, I dont know where these are going to be manufactured. To a large extent I dont really care. Fact is, I think Garrett would not in a million years sell any product with their name on it that wasnt good enough. So I am not worried where they are made (though Japanese would be nice) :thumbsup:
UAS Race Car A look at the UAS site http://www.300zx.com.au/specialssold.htm USED S15 BALL BEARING TURBOCHARGERS THESE TURBOS HAVE BEEN USED FOR 1,000 KM'S ON OUR RACE CAR AND COME WITH HPC COATED EXHAUST HOUSINGS. AVAILABLE WITH EITHER S15 LARGE SIZE ACTUATORS OR SMALLER ONES TO SUIT 300ZX. WILL SUIT S13,S14 & S15, OR 300ZX WITH MODIFICATIONS PRICE: $1800.00 THE PAIR SOLD! (I am not shouting this was a cut and paste from the site)
Some mathematics in support of your case Graham..... The amount of exhaust gasses produced by a s15 is 33.3% greater than that of half the VG30, so that further supports your case for the smaller turbos on a stock zed. Good luck with the GB, they definately look the better choice as a "road" turbo.
reply warning long i was asking because i am almost 100% sure john used jspec oem s15 nissan turbos in his slot car, and even had a pair in the for sale secion on his website see zxz32t post above a couple. Now i know these turbos use a gt28r centre section and i havent been able to find exact specs but i know they are very similar, so the gt28r would work well i dont doubt that, my concern is that maybe the oem s15 bb gt28 would work a little better (this is only i personal thought please prove to me otherwise) because nissan are able to do so much in house testing and change little things to improve the engine and turbo performance before they begin to manufactor a vehicle. I guess and example would be and in our case probably not as severeas this but when nismo created their N1 turbos for the GTR's they sourced garrett bb centre sections and developed a turbo that spec and details were not publised and that garrett could not reproduce for any other of its turbos. Like i said our situation is not as severe however my argument is that garrett may just produce the gt28r and list is specs for off the shelf application of course they would to lots of testing, whereas nissan would take the turbo bolt it to there vehicle and possibly change little things to improve the overall performance. Of course it can then be argued they did do this but it was for the s15 silvia and not the zx so their testing is irrelevant i agree however the results John Porter and darkstorm gave would argue these are a great turbo. In closing i have no doubt that the gt28r will be a great turbo upgrade i just want my own doubts confirmed that the s15 oem gt28bb will not perform any better. I will get in contact with John to try and confirm this. below is a link to the turbos i am talking about this link provided by hakentt from twinturbo.net http://www.performancenissanparts.com/catalog/product_info.php?products_id=1399
Here's some info for the GB & maybe an answer for chewy..... This info was from ttnet a long time ago. And also this link CLICK
