GTScotT

Sorry Martin, wish I could help with the cams.. Stao do you think that housing will be as accurately made as an original TS housing? Especially the shape and sizing of the two scrolls towards the nozzle area.

Sorry I mean't the SR lol, I want to know so I can set expectations for my own

That SR is insane. Is there anything special about it that we don't know? Running VCT or non VCT? Definitely making me think hard about where I want to go with mine

Have checked stock SR compression rings today. Both rings are 1.5mm thickness. Top ring 3.05mm width, bottom ring 3.75mm width. now you check if those will fit in your ACL slugs and go down to Nissan if they do.

He's quoted me on repairing the GT30 core with a G3 core and reusing the compressor side and housings... But turbine would change and cost is up there with a replacement core. am liking the kando more atm due to availability and cost effective replacement if anything goes wrong. Knowing this motor its likely to root another turbo, and knowing Stao he's likely to want to fix it for free every time. This is just a cleaner arrangement and I can maintain a good relationship too. am potentially looking at a tial .63 housing on one of his L2 74mm items for the SR though. I think he's onto something awesome there

LOL im worried that will somehow be laggy. No T67 love for the old pootron? What about a TD06H 25G?

All you had to say is that it got bad leak down results lol You didn't need to prove that the catch can isn't the problem once you confirmed it had bad leak down. We only questions the catch can because we didn't know the leak down results. Anyway. It has been said that other people have not had this problem before (with thinner ring piston kits).. So why not build it yourself this time? Get the block you want to used checked for bore size and follow the machinists recommendation for what size piston it needs. Buy the pistons in a kit and grind the rings to the exact specs your happy with. For reference my CP top rings had a maximum gap of 17 thou, which was good enough for me to work with. Most had a tight 16 thou. Anyway, with any luck you could re use the ACL set with a different brand of 1.5mm rings. To get you out of trouble on the cheap. As noted some of the OEM Nissan rings look to be that thickness, have a check with your own spares and see what you can work out, otherwise buy another set. end>thread/

Can you tell us a little more about this comment? I understand that a leak down was done, but the comment of pulling the motor down being pointless based on the results is confusing me. Did it have pathetic leak down results or was it fine? What's the story? What others are currently suggesting is that your octo breather pussy party setup may not be helping what you are experiencing.. I think you should rule this out for everyone so that we can continue to try and help. I for one do not want to encourage you to build another motor if you dont need to.

They do but for some reason they only sell them as hybrids of the two. Ie 3560-1 or T04R82. I'm leaning toward a simple T67 atm as its not far off what he had in all ways and is cheaply and easily replaced.

We know this. My point is factory has many grades of parts, and factory built motors are as good as they are for that reason. I could be wrong and the bores have plenty of room to hone and suit the new pistons, its just something that crosses my mind when considering a build. Get the block checked by your machinist before going further to make sure he agrees it will suit an 86mm piston of generic type.

Depends how much less they are and if they are less they are. I've just heard too many horror stories where people have built to factory sizes and failed, scares me off i guess. I use what I said above as a rule of thumb when considering a build. Surprisingly I have had a new OEM block with forged internals be PERFECT compression wise with stock sizes (was an SR) but the shop who put that together rushed the rotating assy and it died in many weird and wonderful ways, a few tries over. If its not one issue its another lol.

If your willing to go new pistons over and over why not just get a set of oversize pistons and start fresh? I don't believe in going factory size when building unless its being built with full access to all factory parts. Which means I'd never forge at factory size anyway. I want my machinist to have enough meat to grind so that the quality of the bore is entirely on him.

LOL! the GT30 was similar... it almost always has boost. it only really developed a 'turbo' character when he put a massive stage 5 cam in it.

I already know why it died. The reason for the change is that it is expensive to repair the garrett when these things happen, not because it's necessarily the turbos fault. Garrett themselves no longer make a rebuild kit, so the only things to salvage are the front and rear housings. A new core is $850+ and being the 3rd one the car has had we are finding them to be a little too delicate for the agricultural spec Astron 2.6.. So its time to move to something which is cheaply replaced/repaired in the event of failure (spare T67 cores are about $350 delivered). A Kando is $750 delivered and I can cheaply replace it when he blows it up, which he will. He doesn't need/deserve a ball bearing turbo on there let along the Kando anyway lol

So my brothers GT3076R packed it in. He's been through a few now so its time to give garrett the flick royale. Throw some opinions around guys. Is it T67 time or TD06H 25G? Is for a Sigma 2.6L which made light work of spooling the 3076R .63 (spooled very early, very easy).

Yeap, I wasn't sure about the GTT as I know it comes 6 speed lol couldnt recall if there was a 5 speed model also, but am sure they would use the same box as the 33. The smaller 5 speed is definitely pretty fragile in comparison, but shouldn't feel like its going to explode. Should just feel lighter to work with than the bigger boxes, and like I said should shift easier/quicker with less effort.

wrong. Its the same box as whats in most of the 5 speed RWD cars, except R33 GTST and Z32 twin turbo IIRC. It shouldnt feel like that, if anything it should feel better than an RB25 box on quick shifts. Lighter gearsets and components would make it easier to change between cogs. That box has a problem. I can shift like an absolute MOFO in my S14 (and every other 5 speeder I've driven) and it is the same box. It could be the clutch, but you should take it back to the mechanic and get them to sort it out.

Exactly what was it doing?

Try the original rings in yours and see if they fit. No issue with stock rings in forged pistons, they are just rings. Usually made from the same material anyway. It's just about fitment.

Like i said try do it with a set of used rings first. I have a set of detonation damaged SR pistons at home if you want to try, im sure other members have RB sets lying around if you ask. If your in NSW your welcome to come grab one of my spare pistons and try your luck. hey are a simple thing. Has width and depth like what it says on the ACL site. If the width is right, and the depth is the same as or slightly less it will be fine. I would just make sure you use the ACL oil control ring. Also, is it both your top and bottom comp rings that are too large or just the top?

No mate, I'm saying I have a set of stock SR20 pistons at home (used) which have rings that appear to be 1.5mm thick. What I am suggesting is that you try put the stock SR20 ring on your piston and if it works then order a set of stock SR20 rings for your ACL RB30 pistons. I am suggesting this because you said ACL rings are not available, and they are 1.5mm thick for an 86mm bore, and other brands are thinner IE 1mm or 1.25mm.. So in theory if the OEM SR rings are 1.5mm thick, and they fit on your ACL pistons without fouling the piston itself, you will be able to buy a set of SR compression rings which should have gaps tight enough for you to work with. Let me know if were on the same page.

Well that's just shit. Did you pull the motor down and check the gaps to be the said 19 thou? Definitely the rings which are letting the oil through? Take the manifolds off and see what the valves look like. If the inlet valves are soaked it would indicate its coming from higher above. Not assuming you don't know your stuff, just trying to be helpful. FYI I have a set of SR pistons at home which appear to have a 1.5mm ring from standard. 86mm bore, stock Nissan item. Want me to get a caliper on it on the weekend? I could send you the set and you could get your ACLs checked to make sure they will accept the ring. If anything they may need a minor rework.

22 isn't too big but once you hone the shit its going to open up. I wouldn't be afraid to run 22 and 26 thou ring gaps (top and bottom). I am running 18 and 22 on my street motor which is tighter than.... I won't say.

Good work mate! You deserve the fruit to come

Maybe I will come with you and try kick start a new scene ;-) we can be China's new street gang