djr81

If you have that lot you still need more parts that GAry will not have supplied. Read this is you havent already. http://www.skylinesaustralia.com/forums/topic/374385-bilstein-coilover-conversion/

I understand your point. I just dont agree with it. $40 billion is not a drop in the ocean. It is a shtload of money much of which will be wasted on excess capacity and connections that people wont ever use. Money that could be used far better elsewhere.

There is a vast gulf between saying most people use the internet (which they do, clearly) and saying that most people need NBN sized download speeds so that the latest pirated episode of Star Trek can be downloaded in less than 2 minutes. (which they dont) If you want to make the argument about infrastructure then $20 billion buys an awful lot of Hume Highways or hospitals or schools or universities. Maybe even enough that there will be road leading to your local uni so you can actually attend it in person. Instead of a mass of IT infrastructure that may (MAY) be fully utilised some decades into the future.

There are any number of things that can be argued about - indeed there are 46 pages of oil control for RB motor discussions in another thread that would suggest people arent entirely on top of the issue.I dont want this thread to fire off into the wilderness as I am trying to sort out a piston with good sealing - better than the average aftrmarket package. But I would offer the following observations. That forged piston and ring combination tend to be less tailored to individual motors than the manufacturers would have us believe. There are very few built motors with rings that are fatter than 1.2 1.5 3.0. ACL were one of the few vendors and they stopped making them some years ago. If you dig about you will find some endorsements of their product. The overfill of stock sumped RB26's is as much about the small oil capacity (four and a bit litres) and reducing oil surge as anything else. The contention is that for a similar amount of blowby as another turbo motor (pick one it doesnt really matter) and RB will suffer from oiling issues to a larger extent (Because of the small cross section of the oil return drains). So the idea is to have less blowby than other motors. A reduction in blowby will reduce the amount of oiling mods needed or alternatively allow the motor to run for more kms until they become an issue. That is my contention anyway. If I am over engineering the rings/pistons then so be it but if there was one area of an RB26 you would want to over engineer it would be that.

The drainage efficiency is affected by blowby. In engineering terms it can be assessed by a Froude number. Too much blowby retains the oil in the head of the motor. The issues are linked. The RB26 doesnt have much in the way of area for drainage. Hence it is more affected by blowby than most other motors. Anyway that is my theory.

Well almost no one I know does that, which is probably why I know them - because they occasionally get outside their houses. The overwhelming majority of people just dont want or need the kind of speeds the NBN purports to have. It is only the IT fanbois who are making all the noise and getting all bitter and twisted between 100Mbps and 25Mbps.

It is mostly because I want to see what sort of difference it makes. I have come to the conclusion that RB26's have an inherent problem with oiling that is caused by blowby. Once you reach that point you kind of want to make sure you fix it and that the fix is going to last. So rather than just follow what everyone else does and have the issues everyone else has I thought I would try a bit harder and see if I can do a bit better. Or screw it up entirely which is the more probable outcome. Anyway the custom piston is not complicated. All you need to do is to tell them how you want the grooves for the rings done. Everythiing else stays the same.

Ordered some new rings from JE - had to get two packets of four as per the above part JC2904-3386. Anyway that will give me a couple spare to send off for test. The other avenue is rings from Pacific Engine Parts. A nice old bloke called Trevor is working up an alternative with either 1.5 1.5 4.0 ductile iron rings or the same with a steel top ring at 1.2mm. Not sure what I will do yet - may end up with a mix and match combination. Can get CP pistons made to suit either option.

Well the closer you are to the original rates the less concern you would have but basically there isnt a problem with the 7/5 or 8/6 either. Why not get some Bilsteins and use the rates you want to?

Cant get the file uploader to work but if I could I would attach a quote from JE. For for half a dozen 86mm piston. Basically a modified version of these (Modified for a thicker top ring and an 86mm bore) http://www.jepistons.com/Catalogs/Sport-Compact/Nissan-Infiniti/rb26dett.aspx NISSAN R32-R34 SKYLINE RB26DETT Dome/Dish requires no deburring or preparation 2618 T6 high tensile forged aluminum JE designs are specifically engineered for extreme applications up to, and including, professional competition. In this environment, the higher compression ratios, highest boost or heavy nitrous usage necessitate the higher tensile strength 2618 aluminum alloy. Dome and dishes feature smooth flowing radii for excellent flame travel. 1.2 x 1.5 x 3.0mm ring widths. .827 x 2.250 straight wall carbon steel wrist pin provided. Pin fitting and wire locks included Rings Now Included Rings are as JC2904-3386 package. basically these but six not four. http://www.summitracing.com/parts/jep-jc2904-3386 Cost is $1050 USD. Thicker wall pins are $11 ea extra. Plus shipping and GST for the lot. Have another local option to work through too.

If there is nothing wrong with the pump pressure just leave the thing alone.

Helmut Marko does not hinder Red Bull, insists Christian Horner By Jonathan Noble Tuesday, April 30th 2013, 09:45 GMT Helmut Marko's presence at Red Bull is a help rather than a hindrance to the Formula 1 outfit's ambitions, insists team boss Christian Horner. Although Marko's outspoken views have often stirred up controversy - especially because of his close ties with Sebastian Vettel - Horner claims that Marko's Red Bull advisory role assists the F1 squad by giving it the independence it needs. With the recent 'Multi 21' team orders row having prompted fresh intrigue about the management make-up at Red Bull, Horner argued that he is freed up by Marko's responsibilities with Red Bull owner Dietrich Mateschitz. In an exclusive interview with AUTOSPORT, Horner said: "I have full responsibility for the operation of the team trackside and in the factory. Horner interview: I'm here to win, not be popular "I report directly to Dietrich, who has always been tremendously supportive. He sets high standards. "Helmut has responsibilities elsewhere with the young-driver programme but he has no operational responsibility or input into how we operate as a racing team. He's an advisor to Dietrich, and he's obviously an experienced hand. "Part of his role is that within the Red Bull corporate world, now that it's such a large company, he has enabled Red Bull Racing to retain its independence. That allows me to operate with the freedom to manage the business and manage the team how I see fit." Although ultimate decisions on Red Bull's long-term plans are still down to Mateschitz, Horner says his relationship with the Austrian is on solid ground, and he has never had anything but full support. "Dietrich is the chairman and a major shareholder, so of course I answer to him," said Horner. "But he gives me the autonomy and he has a trust in me that I represent the team as well as I can, and he gives me very much a free hand to run and operate the team; to recruit, to operate the team the best way that I see fit. "Of course I keep him updated. And of course with any major decisions be it on the drivers for example it will ultimately be with him. "But he has always followed and backed the team whether that be an investment in capital expenditure, or be it in an engine change."

Failure of the oil pressure sender unit is common. Check and/or replace that before you do anything else.

Well the ACL pistons got sent back so I am currently pistonless. But I have a couple of options left unexhausted for non stock 1.5mm rings and will see how they go. Will make sure the block is viable at 86mm before I order any pistons.

The leakdown numbers are large - too large to believe that any amount of catch can/breather set up will help the issues and too large for me to want to wind any more hp into the thing - which was the whole point of getting a built motor. The comment was simply that I didnt think it was worth pulling the motor apart to diagnose the problem. There is too much blowby is the core of the issue. Dont need the motor in a bazillion bits to know that. I dont want to trouble shoot the breather system. When first built it had the same breather system as the stock motor - basically a Nismo catch can and that was all.This set up was fine with the tired original motor. With the built motor it puked litres of oil into the I/C and fouled the AFM's so much that the thing would lay smoke screens down the straights. Every change to the breather/catch can system has been after establishing there was a fundamental issue. It was simply an attempt to find a bandaid fix for a motor with too much blowby. To an extent that has worked. But it wont ever be enough. I need to build a motor with good blowby numbers in the first place. When you talk to builders over here they get all nervous and will only ever volunteer 15 - 20% leakdowns. So I have no real confidence that just doing what everyone else does is going to work well enough. Hence the 1.5mm rings which I would have been happy with. Unfortunately the ACL rings didnt fit and I cant find a piston with a similarly thick ring. Hope that is clear?

And there I was thinking I had done an awesome job of disguising just how monumentally frustrated I am. Other than referring to the car as the Exxon Valdez and carrying on like a pork chop about it all the time, obviously. Yeah it looks like an octopus orgy. But please understand it started with a couple of vent lines from the breathers in the rocker covers to the catch can and grew from there. To be fair it works at Wanneroo. Just not Collie because there are too many left handers for the content of the catch can to drain back into the sump. The take off for the vent to the can is well above the oil level so I dont believe it is coming out there. It puked oil before I fitted the vent - at Collie and Wroo. Stopped at Wroo afterwards. In any case it fills the 2 litre or thereabouts can in two to three warm up laps of a track that is a mile long. The last time there was oil all over the engine bay, on the quarter panel, the side skrits, all over the front suspension, wheel, windscreen and the puddle under the thing was the size of a family pizza. So not a small amount. Catching it with anything smaller than a 44 gallon drum wont work. Sump capacity is only 9 litres so even the P76 boot mod has its limitations. Anyway none of this is getting me closer to a piston with a 1.5mm top ring. Or a suggestion (Other than somethng with total seal rings) for a piston otherwise.

5W50 which I have always used. Never had a problem with it.

Well its going to get honed - just to 86.0mm not out 86.5mm. Not going to chuck it together with the finish it has straight from Nissan. Pistons wouldnt fit down the bores anyway.

I have bought a new N1 block for the new engine build so I am starting fresh. It has bores less than 86mm. So why not use 86mm pistons?

So JE won't do you a 1.5mm top ring your saying? I asked them for a ring with the same dimensions as the ACL one. They said no. The next step may have to be asking them for a custom piston for a 1.5mm ring of their own dimensions. Is $$$'s, I would guess. They don't do an 86.0mm piston and like alot of people start at 86.5mm. With everything you've done it shouldn't be a problem even with a 1.2mm top ring. It sounds like it was possibly screwed together poorly? Slap happy job? Ring gaps all probably not measured or done or who knows? I dont believe it was a slap happy job. In fact quite the opposite given the circumstances I beleive the shop in question tried bloody hard to get it right. Which is perhaps even more of a concern. Was the block torque plate honed do you know? Yes, believe so. Also what oil are you using? Mineral oil for run in and then Mobil 1.

Well listening to the race commentary & interviews last night (yeah I know I cbf'd watching it Sunday) Webber basically said Marko placed the Porsche story in the media. So I would suggest Marko is worse in that he appears to be actively trying to undermine one of the teams drivers. Why do they employ that clown?

Yes that is why I want the thick top ring. I had a standard motor running 450 horsepowers and it didnt have any issues. After the rebuild it has more issues than Readers Digest. The fundamental difference between a tired stock motor (With no head drain, standard restrictor,no big catch can) and a brand new build forged motor (which over time collected all of the stuff listed below) is in the pistons and more particularly the ring thickness. I tried JE who do custom rings - just not custom enough. I have fitted: A drain from the back of the head. A small restrictor. Mines baffles (Which I dont think help anyway). A Nismo catch can. Another big catch can with a return to the sump. A dash fitting in the sump to help vent blowby straight to the catch can. In getting to that point I have been through umpteen iterations.

Here: http://www.aclperfor...rgedPistons.htm

Nah NSW is a bit of a drive from WA. I have the original pistons/rings from my motor so could check those. But like I said stock rings with forged pistons?

I see what you are saying. I could try a set of Nissan rings for an RB26 - not sure what they have available or how they match up with forged pistons. Has anyone tried this?