DoughBoy

Why are there 2 dots for the AX53B70P28?

2530's have been around for ages compared to the new Apexi's. A user on the SkylinesDownunder forum (Tyndago?) has dealt with a car with the AX60's on it - it got 540awhp(~400awkw) with 280 deg cams on an RB26. They sound like a pretty good turbo though.

PM sent.

Gah, don't make me pull out the cam and start taking photo's again. Wasn't discussing the performance, design or flow characteristics of the Jun piece, just the fact that the internal parts of the manifold are not machined from factory, and that the only polished part is the external.

R34 CAS is different. To use a 33 or 32 CAS you need to change exhaust cam. AND the inlet plenum is shiny. Ball bearing turbos too. Oh and the important thing, red rocker covers!

HKS sell them for 258,000yen (~$3500) including a wastegate. It's a T25 flange though. Most fabricators or exhaust shops would be able to hack one up - RNZ11S posted about them costing $800 in stainless. Should be able to make any turbo fit that with a small adapter.

Have to disappoint you, but the Jun plenum for the RB26 isn't smoothed out as much as you think. The only part which has been finished after casting (besides the bolt holes) is the outside. Go Go rice factor! After saying that, there is plenty of meat in the runners for them to be ported out. Jun may feel that anyone going to spend that kinds of dosh on a plenum will pay someone to matchport/ enlarge the runners anyway.

Don't hesitate in buying it then. The cost of the stainless and getting it mandrel bent in 1 piece would cost alot more than $800, let alone the flanges + welding it up.

Hi guys, Due to difficulties in my RB26 engine buildup I am offering up my pistons + rods for sale. Apexi 86mm V-Max SPL pistons - these are the top of the line pistons, rated at 1200ps+ and come with larger 22mm gudgeon pins, rings and a manual in Japanese to stick on your mantelpiece. Rec. retail for these are 240,000Yen - around $AU3000. HKS step 3? rods - the top of the line rods, only due to the larger pin needed for the above pistons. Made by Carrillo. These retail at ~200,000Yen, or $AU2500. I bought these at near retail price for my own use. They have not been installed in any motor yet, rods have surface discoloration from sitting around and being handled alot (people always want to "just hold them a minute" supposedly to feel their weight). Will only part with these for $4000 firm. Please don't try to barter on them, or make outlandish offers as they cost me a touch over $5000 landed here.

Hi guys, I'm in need of a standard RB26 crankshaft. Preferably R33/34, but would consider an R32 one. Must be in good condition (have 3 bummed out cranks already). Please contact me at cbaloglow@netspace.net.au . Thanks!

Ah ok, just as a side note the HKS manifolds to suit T04 work as well - same stud pattern. Also the genuine HKS articles are made from 1 piece - no welds in any of the runners to disturb flow or provide a break point.

$800 is a pretty good price for a genuine Trust manifold. The last time I checked they were 190,000+ Yen rec. retail.

What about turbo efficiency? Exhaust manifold design/efficiency? What if the engine is highly tuned to operate at a specific rpm (powerband)? I'm not sure if you are formulating a generic calculation to determine wastegate sizing or just providing a guide to wastegates based on current data.

What about a scenario where more boost = more power, but the amount of exhaust gas used to bring about more boost is by far less than the volume of exhaust gas created by the additional boost? Just to throw in some (hypothetical) numbers, say 5lbs more boost (on a turbo just entering it's center efficiency island) creates 200cfm more exhaust gas, but only requires 30cfm to put out this additional boost. I know these numbers are way off, but just wanting to illustrate the situation I am trying to describe. Edit: Also, about this "response" of a wastegate. Just say you are "coming on boost" very rapidly (as most larger, aftermarket turbos tend to), wouldn't you think that a wastegate that only needs to travel ~5mm to maintain the desired boost level (i.e. a large gate) as opposed to a smaller wastegate that would need to travel ~10mm to vent the same volume of gas would be able to do this faster, hence be more "responsive"? I concede the smaller one would be able to be more accurate in it's flow limiting, but then again wouldn't an "intelligent" boost controller be able to manipulate these regardless?

Hi guys, just need a bare RB26 block. Only bolt on part I need with the block is the crank girdle that came with that motor. Otherwise, can be completely stripped. Please contact me at: cbaloglow@netspace.net.au . Sydney preferred, but would ship from interstate.

HyperRev #37

Although the price vs performance is an important factor, it's not really going to help a company that exports from Japan much. Garrett being much more of a global company would have more resources and opportunities to reduce overheads manufacturing these components. I wonder what retail prices of Garrett turbos are in Japan?

Uh ok.. well I got out the measuring tape... you sure you don't want to go first Sydneykid?

The HKS rod is for an RB26, the bent rod is out of an SR20, the rod with the piston on it is from an RB26 - tore down the motor over the weekend. The few RB25 rods that I have seen break at the 'neck' area just where it contours down to the beam of the rod - high revs being the cause.

OMG you violated my personal web area! I feel so used.

Oh OK!

RB26 rod!

Heh while I was typing that essay you beat me to it Roy

SR20s have a T25 flange. Ah la RB26. The single bolt-ons for RB20/25's have larger compressor/turbine housings. Maybe they need to flow more considering they are a larger motor? Yes it is a second hand turbo. Yes I have had brand new turbos in the 25xx range bought from a HKS distributor in Japan...and they are the same. JNR32R from these forums bought one - if you are still in doubt ask him. Rick Shaw also bought one for his personal car. MRK25T is another from this forum. Ask Croydon next time you are there... but I'm not sure if they have dealt with budget single turbos like these. I've got some articles from HyperREVs with pics of these, I'll scan them in later for your amusement. As another point, the new GT-SS and GT-RS just use Garrett compressor + turbine covers. Yes I've had some come through here, I even showed you a set of GT-SS. Are you going to claim they are not HKS turbos now? I think the bottom line is that because they are not illustrated in the HKS catalogue or on the website and the fact that few people are using them leads to posts like this...

Low km rods = rods from a motor that has not been used much.