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Back from nats. Everything seems to be okay. While John turned the MAP cut up, it was still hitting it so we took the wastegate apart to find that one of the banjo fittings had been improperly manufactured and had no hold in it. Fixed that, wacked in a 10psi spring, and went for a burn with Cam at the laptop. I didn't get to see the numbers as I was driving, but he said that it was running a bit rich on idle, bit lean off boost, and fine on boost. We noticed that the extractors were getting pretty hot, like glowing red, after long cruising. I assume this is due to the lean off-boost driving. Gonna have a proper go to re-tune it in the next few weeks.

P.S. I appears that if I drive calmly I can stay off boost all together. This might change when I have Thriller + luggage in the car, but not by too much.

Thanks for the replies guys. And a MASSIVE thanks to John (CGXPWR) who tonight not only welded a mount for the wideband to my dump pipe, but also had a quick look at and fiddle with the tune to make sure it was safe enough to drive to Palmy. He seemed to think that it was a relatively safe tune regardless, so I'm interested to hear other's opinions on Friday

Bring a note pad, baby.

I've already got the spring, and I was planning on softening the spring anyway, so I may as well put it in, I won't be tempted to go crazy with the threat of an expensive rebuild hanging around. Physically the turbos look the same, but the comp has gone from 0.40a/r to 0.63a/r so obviously less of a restriction.

Yah, we were using Win7 last night. A HUGE thanks to CXGPWR who is going to weld an O2 sensor fitting into my exhaust tonight.

Does anyone coming to nats actually know how to tune a link?

That's a possibility, got a million holes in the boot. Well, pretty much what I'm going to do is reduce the boost. It's not the BEST option but it really is my only one in the short term to get to Nats. Long distance driving is generally done off boost anyway. The car is tuned for this so I assume it will be safe enough to drive at 100kph off boost.

It sounds like a plan, assuming Cam is okay with this and thinks he knows what he's doing How does the wideband attach/fit in though? I'm not sure I have a bung in the new setup.

I don't own it anymore

I wish I had that time, but sadly no. And no GC who has any idea what they are doing, only Thriller, and we all know that he's an idiot

Thanks Fred. All this is pointing to me not being able to drive this fucking thing to Nats. I have purchased a smaller spring to get me away from the MAP cut for now as I'm not a fan of it leaning out chronically and having something go disastrously wrong. MY last tune was using an AFR of around 13.0. I believe this is rather high? While I have no way of testing this, the turbo is not hugely bigger than the old one so potentially I will not be increasing my air volume by too much, therefore not leaning it too much. I understand that the compressor maps, etc will cause different amounts of fuel and timing to be needed at different rpm/throttle position. I do not have time to get a wideband and go road tune it. I don't have time to do screen shots and post them up. I am out tonight and tomorrow night am meant to be driving to Palmerston North.

Oh I can read it on the gauge. BUT, thinking about it now, you are right about the MAP cuts, Boe-rad. The MAP cut is set at 200kpa which is 2 bar (29psi). Atmospheric pressure is 14.7psi and the turbo is boosting 14.7psi = 29.4psi = above the MAP cut. Now wonder it doesn't like me putting my foot down. I have bought a new spring for the wastegate 9-10psi, should keep it happy(er).

Thanks so far! Brad: I completely understand what you're saying there. I am pretty sure that I'm overboosting as the car is tuned for a turbo which makes 12.5 psi, and it's now running 14.7psi (the boost gauge in fact seems to go over 15psi). I definitely DO NOT want to grenade the engine. We did have a fiddle with the MAP and RPM cuts last night and it did become much more drivable when we made them higher. However, I am fully aware that this not the best option in any circumstances. A retune is on the cards, but I do need to make it to the Nats! Cam: You sound so optimistic! I am happy that the engine can handle the boost levels, that's no problem, it's whether or not the ECU is giving it enough fuel at this higher level. We looked at the MAP cut and it seemed to be set very high, like 200 kpa but I feel we were reading it wrong (although maybe I saw it hit 250kpa at one stage, but that's like 36psi and I doubt the turbo can even push that/the boost guage says about 15 and there is a wastegate there that I have heard working). I think that the smaller wastegate spring is probably the safest way to go at the moment - what say you people?

Would you recommend that I pull my boost pressure down to what it was originally tuned for (or below)? P.S. I always though that ECUs were meant to be smart and add more fuel if you change boost pressure, etc. People are adding boost controllers/other turbos to standard cars all the time.

Let me preface this by saying that I know very little about EFI tuning, and have only seen the software running once (last night). Hey guys, I've just put a new turbo setup on my car. Old setup: RB25DET T3, internally wastegated, 12.5psi New setup: Master Power GT28, 38mm external wastegate, 14.7psi (if not more). The problem is with my ECU, it's a LINK LEM G3. It appears to have both an RPM cut (soft and hard) and a MAP cut (soft and hard). With this new turbo, the car has become somewhat undrivable if you are flooring it. For example, in 5th on the motorway, if I put my foot down, they turbo will spool but what I assume is the MAP cut will kick in before I even get to 110kph. If I slowly put my foot down I can get up a lot faster. The cut is fucking violent, it's like I'm hitting a brick wall. Is it possible that the tuner set the MAP cut to just above my old wastegate level? And now that I'm going above it it's not having the best of times? The RPM cut is similar. The car feels like it wants to rev above my current hard cut but it cant. This is more obvious if I rev up slowly then hit the cut. It cuts at around 6000rpm. NOW: I had a look at the maps. It appears that the car has been tuned to 8000rpm. Will I have issues if I change my rev cut up to 8000rpm? What about the MAP cut? Any ideas what I can do here? I am toying with the idea of chucking a 10psi spring in the wastegate just to keep it happy... Obviously I'll get it professionally retuned at some stage, but... Not being able to put my foot to the floor sucks!

Yeah man, gonna cost moneys though! Good to know there is a helpful workshop nearby though

Tis all good, the Grey Lynn radiators place is gonna sort it.

Will they actually let you do that?

Too far away, I want to get it fixed before I go back up there on the weekend. Plus he'll kick my ass because he only just installed it and I farked it.

I've cross threaded one of the -10an fittings on my oil cooler and rather than buy a new cooler I'm keen to just weld another fitting on. Can anyone close to Auckland central help me ASAP? Like, before next weekend? Cheers Leon

Shit yeah, I am interested in trying to make some CF Chevette bumpers.

Bring it to Tony's on Saturday, I'm keen for a geeze.

I don't think that we will get to Hams in time to get a convoy going. We'll be leaving Auckland at around 5-6, then will sit in traffic for 2 hours on the motorway.

Straight after work on Thursday, earlier if possible.