Jump to content
SAU Community

Recommended Posts

I think Simon's suggestion at post #2 made the most sense given the OP is in the UK and not running E85.

Looking at this thread, if the OP's setup consists of bolt-on airflow modifications only (inlet pipes, turbo, FMIC, poncams and exhaust), I'd suggest his dyno might be happier than the typical Australian spec. 260rwkW from 13psi on an RB25 is not something generally seen.

It's 252RKW (301KW crank) @ 6300 @ .9 BAR /13PSI

In the attached file you can see how boost creeps out.

My target pressure was 18PSI

post-33912-0-89031000-1404943949_thumb.jpg

Hmmm looks like there is a real issue there, exhaust/inlet restriction?

Mine held 18psi near perfect with the Power FC boost controller. I did have a few problems with the bost fluctuating up and down between 15-18psi pretty rapidly but ended up sorting that out.

Hmmm looks like there is a real issue there, exhaust/inlet restriction?

Mine held 18psi near perfect with the Power FC boost controller. I did have a few problems with the bost fluctuating up and down between 15-18psi pretty rapidly but ended up sorting that out.

Hello,

Was your Turbo the HKS Pro S?

Mine is just a Hybrid rated at 380HP.

If I set it to say 14PSI target the boost curve would be more linear

I guess I am just asking too much from a small turbo.

I could double check if the gate opens too early but have no high hopes.

Otherwise I see no restricting factors.

Blitz FMIC

HKS DUMP

Tomei 4'' downpipe / Pon Cams

HKS 3'5 exhaust

The kai will NOT go 300kw on petrol.. Probably Wouldn't make the power you have now. As earlier stated your best/only real option will be a GT30 if you wanna do 400hp on the tarmac ;)

Thanks,

GT30 would mean high mount / ext gate then ...(?)

Would need to do some research on that I guess.

If the KAI would do 280KW+ that would be enough for me but I think it is rated at about 400HP?

Making less power than I have is not really an option :)

The Pro S was a better turbo and despite all information to suggest that the KAI should be better it does not live up to they stats HKS post. I was disappointed as I originally ordered a PRO S and Nengun said it was discontinued and the KAI was better. So I eventually moved on to a hypergear turbo. Was frustrated with the lack of support from HKS who basically said the turbo wasn't making the power because of the tune or something that I'd done and after only 1 or 2 replies began to ignore my complaints

The KAI is not a bad turbo, im not going to say that at all, it's pretty great for a street car. However it doesn't produce the power of the old PRO S so as above don't expect it to go to 300rwkw, even on E85 I don't think you'd quite get there. The most I've heard of is about 260rwkw on a 25 neo with poncams

How happy are you with Hyper-Gear?

Spoolup should be somewhat worse compared to the HKS.

Here the PRO-S making 320KW on E85

http://www.skylinesaustralia.com/forums/topic/412682-300-rwkw-gtst-top-shelf-parts-only-price-drop-for-members/?hl=hks+pro

Joeyjoejoe....'s result is often quoted for the Pro S, but I think even he admitted it seemed to be freakishly good compared to others. More common was around 260rwkW, and a touch more with cams.

I've spent a lot of time trying to find a turbo like Pro S, but haven't got there yet. Shame the Kai wasn't a worthy successor. Also, by the way you can buy the Garrett equivalent of the Pro S, but the issue is trying to find a decent turbine housing.

We have to remember what was available when HKS put those GT Pro S turbos on the market - SFA . There were no Garrett IW GT30 turbine housings then so you were pretty much stuck with a Pro S or an external gate . Or some bastardised machined out dinosaur T3 IW housing .

If you can't rat up a Pro S turbine housing then you may need to look at the GTX3067Rs , we haven't seen one yet on an RB with the 0.63AR IW turbine housing but its worth consideration .

The 2835 KAI looks like a band aid for the Pro S version . It's basically taking a GTRS and putting a cropped GT30 turbine in it so the value is a slightly larger and heavier turbine in a T3 flanged GT28 0.64 AR turbine housing . It bolts straight up and takes the standard dump flange .

I personally reckon that if you can't get a Pro S housing and its unique dump pipe (or make the dump) you are better off with a GT30 based turbo even if it means using the smaller 0.63 turbine housing . Once your set up for the manifold spacer and GT30 IW dump pipe you open up a range of turbo options you don't get with much else .

Had Garrett had the GT30IW housings back in the day there probably wouldn't have been Pro S housings and dump pipes .

Also consider Hypergears turbos , cheers A .

Im more than happy with the hypergear so far. Stao's customer service is great and he is always updating which means you can send the turbo back to be upgraded for better performance. Also when it comes time to rebuild the turbo, I dare say a hypergear would be cheaper to rebuild. The main problem with the 2835 is the price. If it was resonably priced they would be good, but I think I payed about $3500 for my HKS turbo where as the hypergear cost under $2000. Fair enough the HKS turbo comes in a kit but it's not worth the extra money as far as im concerned

The big issue for me as well is customer support. As I already said, expect Zero of that if you go HKS where as at least hypergear is local and Stao is willing to discuss issues etc. Customer support probably isn't an issue with the HKS but for me when I originally ordered a pro s, and had seen so many pull around 280rwkw, to then have mine under perform that I was kinda after some answers. I was rather unlucky in my Situation as I would have been one of the first to get one of these so Nengun didn't know it would be worse then the Pro S so I couldn't really blame them for selling me what was essentially a super seeded part

@89CAL ->

That must have been a disappointment. Especially after investing quite a bit of $$.

Would you have dynos of the HKS vs / and the Hypergear?

Does the HG introduce more lag ? (it should)

What is your current power?

My turbo make 14.4 PSI (1BAR) at 3500 rpm.

That's the benchmark I compare against for spoolup.

Edited by Torques

Hello,

I was hoping that the bridge between low lag and high power could be drawn easier these days.

So billet wheels and ball bearing would be of my interest.

All things being equal the HKS is a bit aged now and is 'only' rated at about 410HP (CRANK) or so.

Back in the day that that was good power.

I would need to do more research on available turbo options and how well they spool up on RB25.

Making huge power is no so difficult but I need my car to be torque rich and responsive.

My current benchmark is 1 bar (14.4PSI) at 3500 RPM and the new turbo should be in that region while holding 16-18PSI at 6500RPM.

I once did the maths for this leading to the required compressor map.

I will revisit Hypergears turbos as well .. Stao has many options available.

We have to remember what was available when HKS put those GT Pro S turbos on the market - SFA . There were no Garrett IW GT30 turbine housings then so you were pretty much stuck with a Pro S or an external gate . Or some bastardised machined out dinosaur T3 IW housing .

If you can't rat up a Pro S turbine housing then you may need to look at the GTX3067Rs , we haven't seen one yet on an RB with the 0.63AR IW turbine housing but its worth consideration .

The 2835 KAI looks like a band aid for the Pro S version . It's basically taking a GTRS and putting a cropped GT30 turbine in it so the value is a slightly larger and heavier turbine in a T3 flanged GT28 0.64 AR turbine housing . It bolts straight up and takes the standard dump flange .

I personally reckon that if you can't get a Pro S housing and its unique dump pipe (or make the dump) you are better off with a GT30 based turbo even if it means using the smaller 0.63 turbine housing . Once your set up for the manifold spacer and GT30 IW dump pipe you open up a range of turbo options you don't get with much else .

Had Garrett had the GT30IW housings back in the day there probably wouldn't have been Pro S housings and dump pipes .

Also consider Hypergears turbos , cheers A .

Edited by Torques

Ignore it, it means jack shit. I remember being shown that when I was being told the KAI was the new and better turbo

Didn't happen at all. I'd have to find my dyno sheet. My current setup needs an exhaust restriction removed then a re tune but hopefully will be around 300rwkw, touch more with any luck

Yes, already written off the HKS.

Not worth it judging from you replies.

Which Hypergear did you go for?

Ignore it, it means jack shit. I remember being shown that when I was being told the KAI was the new and better turbo

Didn't happen at all. I'd have to find my dyno sheet. My current setup needs an exhaust restriction removed then a re tune but hopefully will be around 300rwkw, touch more with any luck

Yes it was unfortunate and hardly honest of HKS , or their reps , to claim the KAI was going to be as good as the Pro S version .

I remember looking at pics of that turbo here and thinking hang on , no way the 0.64 AR GT28 T3 housing was going to flow like the Pro S one . The machined out turbine housing may flow a little better than it would with a GT28 turbine in it but from Garretts questionable turbine maps the efficiency numbers aren't very good .

I don't think any turbo with the cropped GT30 turbine ever worked terribly well unless it had one of HKSs GT30 turbine housings machine to suit . For some unknown reason Garrett haven't offered their GT30IW housings to suit this turbine , maybe there isn't enough material in their castings .

Just on power figures and 2835 Pro S , there was an optional 0.87AR Pro S housing if you didn't like the usual 0.68 one . Don't know the boost onset difference but power limits would have been higher with it .

A .

@89CAL: From following hypergear's thread, I remember you've got one of their testing ball bearing ss2. I have the same turbo internally gated. Obviously not as responsive as the 2835 but pulled 312rwkws on 98 fuel, 20psi by 3800RPMs. Its more of a 3076 in .82 turbo. They have made an vnt housing for it, unfortunately only for external gate. Buy that housing and it will pulling 24psi on 3500rpms and that will be about the same or better to a HKS2835 ProS while making heaps more power.

Edited by GeorgesR34

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Got started on the modification to make these splash plates fit over the long weekend. First the surprisingly time consuming task of swapping all the cam camp bolts to Tomei cam cap studs. I did the method of removing one bolt at a time, applying loctite to the stud, double nutting to torque as the manual described. Then carefully unlocking the nuts without disrupting the torque of the stud (and going back to re-torque a few times when it slipped). Finally applying the nut and torquing to spec. Repeat x28 Next up I went about removing the stock cam cover baffle so I could ensure it was fully clean after drilling for stud clearance.  As the blind rivets holding the baffle on were domed I used a punch to mark the center then used 4mm drill bit to carefully drill out the rivet without going too far part the baffle. As seen in other thread here is what is inside the stock baffles I decided on M4x6mm bolts to bolt the baffle plate back on with. I used a 3.3mm drill bit with some tape to mark the depth at ~8mm. Next was to tap the threads using a cheap bunnings kit M4x0.7. With the baffle removed I also drilled out the spot welds holding in the baffle plate oil returns. Unsure whether this was the best option or if I should have cut holes in the Hypertune splash plates to allow the oil drains to still function... time will tell. I then removed the the Hypertune splash plates so I could rest the cam cover on top and use a dab of grease to mark where the studs impacted the oem cam cover baffle. The most obvious spot was on the hump from the stock mesh is held. Using this hole as an anchor I bolted the oem baffle plate back into the cam cover and lined up the Hypertune splash plate. Marked the rest of the holes for the studs and drill those out too. Total 32 holes drilled and 12 threads tapped on the passenger side cam cover alone for this bolt on part that totally clears all OEM cam covers.. Drivers side next as well as some E85 safe fuel foam to fill the space behind the behind cam cover baffle plates. oh and some lock nuts for the splash plates of course.
    • I had the same previously, and it really shits me. They just run off red book averages or whatever as the maximum insured, there are never good quality cars available to buy for anywhere near those prices. I don't even understand why they do it. Sure having a customer overinsure then false claim is a risk, but how often does that really happen in the world, 1%? 0.1%? On the other hand, all 10-20% above redbook listed prices and charge 10-20% higher premium, surely that is more profitable for those cockroaches
    • My take on gg2 48mm, 54mm, 58mm, and 62mm compressor map for same size compressor vs gg1 : All gg2 only outflow gg1 above 20 psi. As all g gen 2 surge line at lower left of comp map move to the right, all gg2 sacrifice spool vs same size gg1, surge line move to the right worst for 54mm gg2. So for same size compressor if you want best response, use gg1, if you want max hp at >20psi use gg2 but you will be laggier vs same size gg1. Max compressor efficiency drops to max 75% on all gg2 vs max 76%-80% of same size gg1. Iirc lower efficiency means hotter iat less dense air so lower hp at same operating point of comp map. Also curious why gg2 is mapped to lower max rpm vs same size gg1 (only 48mm size both gg1 gg2 mapped to same rpm) : 54mm gg1 165,000 rpm  vs  gg2 160,000 rpm. 58mm gg1 150,000 rpm vs gg2 140,000rpm. 62mm gg1 145,000 rpm vs gg2 140,000 rpm. If gg2 can safely spin to gg1 rpm then they can flow a bit more than as mapped. Good thing that all gg 2 interchange compressor and turbine housings with same size gg 1. So gg1 owners can buy gg2 chra only if planning to boost >20psi.
    • My stuff is all with Shannon's, granted, I don't really have imports I'm driving on the road, however, I've had multiple cars at the same time with them. Presently we have the Landcruiser on laid up cover, Sarah's Kluger on full cover, and the house insured. About 18 months ago Sarah wrote her Subaru Liberty GTB off, insured with Shannon's, and the payout, and buy back of the wreck was super quick. In 2020 we had the VF Commodore totalled in a major hailstorm. Storm was on the Saturday, I called on the Sunday and lodged it, vehicle was towed on Tuesday night, assessment team called on Wednesday to say it was a total loss and get payout details, money was in the bank on Thursday morning. Have had a few other claims both at fault, and not at fault, over the years, and never had an issue with them.   Funnily enough, they're also the cheapest insurer I find for things like Sarah's Kluger.   I will say I'm less impressed dealing with them lately around "the experience", as a lot of their staff that you deal with aren't car enthusiasts. Shannon's has a much more main stream feel ever since they decided to become "big corporate", laid a heap of staff off, and then hired a bunch of non enthusiasts. At the same time they've been making a push to be less "call us and we'll personally have someone who cares help" to "hey, this computer can do stuff for you" and are trying to get more square pegs to fit round holes. (That's just the vibe I get from them). Again, have had no issues with claims with them, but get a bit of a "less personal" feel from them.
    • A thing I wasn’t happy with with enthusiast was during the initial phone call they told me they’d insure it for 130k but needed photos.   I then sent them photos and they told me $80k as there were other cars either similar modifications available for around that price, I told them to send me the links to said cars so that I can buy them. i then sent the modification list with prices of the parts (no labor) and the price then came to 115k, which is still shy of the 130 that was agreed in the initial phone call 
×
×
  • Create New...