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I thought I best get around to starting a build thread on here, I did introduce myself a while back but as things are really moving along with the car now, so I need to start ingesting the wealth of turbo knowledge on here.
Over the last 12 months I supercharged the car (don't kill me yet) and recently got offered a turbo kit for good money, so I decided to take it (am I your friend now?) even though I'd only been supercharged two months...
I guess the boost bug has bitten me.
So I took the charger off and sold all the bits and I'm in the process of collecting the new parts of the build, boost solenoid etc. Thankfully all the messing about with an intercooler and installing the MegaSquirt etc is already done.
Tuning the M45 seemed fairly straightforward, never had any knock, got reasonable power from it. However I suspect with the T28 I'll be running that I need to really get to grips in much more depth with tuning, my ignition table was pretty tame on the charger, I expect it to get somewhat more complicated running the turbo.
So the turbo is all on and working, at the moment I'm just running the actuator pressure until I get another couple of bits sorted. Done some initial tuning to make it safe for the time being and it still pulls very very well.
Plans for the future;
* Uprated clutch, looking at a 6 puck competition clutch
* Bigger Intercooler, mine is too small, going to swap it for a top fed setup and get some custom pipework bent over the radiator for me
* Boost solenoid
* Move the boost feed to post-IC and pre-TB as I lose some over the not so efficient IC I have
* Alloy radiator - don't know why I don't already have one =S
The only thing I seem to be experiencing at the moment is a really bad vibration around 3800-4300 rpm. It feels like it's right underneath my seat so I wonder if the exhaust is rubbing or whether it's something more serious. The engine/turbo are as smooth as silk so I don't suspect it's those. More investigation needed!
Also moved the feed for the actuator to post-intercooler/pre-throttle body. Now seeing 7psi in boost so I guess that's what it's rated to then!
Got a Stage 4 Sprung Competition clutch on the way, and a thick core alloy rad next month too.
Once these are in, I'll be installing a boost solenoid so I can help along the spool and PSI figures.
Feels like a never ending list... after this I need to sort a bigger/more efficient IC and some new over the rad type pipework. And I also need to get a new downpipe section made up as the current one is too restrictive.
Neatened the setup some more, and painted the IC pipe graphite grey for the time being until I re-do my intercooler setup completely.
Just remembered looking at that pic that I need to trim down the outrageous PCV route until I get a catch can arrangement sorted.
Got a Stage 4 Sprung Competition Clutch coming in a few days so I can start looking at more power.
One thing I am worried about is a strong vibration that I'm getting higher up the rpm range, from around 5,500. I can feel it through my seat, and does sound like it's coming from the bell housing area when driving. It's very hard to trace though!
The downpipe doesn't appear to make contact with the chassis/gearbox anywhere but I wonder if it's still resonating? or could it be a flywheel issue? I don't suspect it's the engine but I'm not including the harmonic dampener in that!
Next steps:
Boost Solenoid
Bigger IC
Bigger downpipe
Alloy Rad
Not sure if that's bordering on an order to use the term Nb.
I'll be continuing to use Mk's.
As for VVT I'm leaning towards ecu upgrade that way everything is consolidated to the one unit. Just need to figure out what wiring etc needs to be adjusted to suit.
Having to go back to my build on Mx5Nutz to remember what I did after this point!
So... I had the comp clutch fitted, still going good to this day, although it's a pain in the *** in traffic, which if any of you have ever lived in Manchester you will understand.
Then I picked up some ID1000 injectors that came up at a good price.
These have probably been on of the best purchases I've made on the car. Idle brilliant, and there's so much space for extra power in the future.
I was finding the stock downpipe I had fitted to the car somewhat restrictive, so me and a mate tried welding together a downpipe for it, which worked fine for a few days but then it started blowing. So I send the manifold back to the guy who made it, and he created a 2.75" downpipe for it, and increased the stud size from m8 to m10.
This was a much better improvement over what I had, the studs actually worked on the road and the new large downpipe made it a whole lot nicer to drive. Unfortunately I still needed to run a gasket on this between manifold and turbo because the faces weren't machined, and this inevitably disintegrated every so often, and it was a bugger to remove the turbo from the manifold because I had to drill out the turbo holes to accept the studs due to them not being perfectly lined up.
Eventually I got bored of various issues I had with it, and decided to sell the kit around October last year, with the promise to myself that if I went turbo again I would go to Flyin Miata or similar.
Around the same point I bought my first house, which comes with suitably sized garage and large driveway (we're talking British sized here!)
So, there's a good few months then where I just parked up the car and left it because it was slow and boring.
Then came September this year, where I thought bugger it, I'm getting the car back on the road and I'm buying it a turbo. I sent the ECU off to Reverant to have the firmware upgraded and the digital wideband input added. This made a massive difference to the running of the car as my firmware was ancient. I had the rusty sills repaired. I bought a Nardi wheel for it. And then I started looking at turbo kits.
Thankfully, since I sold the last kit I'd been putting money aside for whatever I did next, so I decided to order a kit from Flyin Miata. I customised some parts out, which I wish I hadn't (woops), but I was quite an excited boy when a huge box turned up at my work!
Last week I booked off work and spent the whole week working on the car.
I did the head gasket, and fitted the kit. I also added a 13 row oil cooler and thermostatic plate, and a dash swap - it was a busy week.
As part of the kit I'd bought from Flyin Miata I decided to upgrade to the inconel studs, having had loads of stud issues in the past I'm rather hoping these will be money well spent.
Anyhow, that brings me to today. I need to get the car mapped, I need to get an exhaust made up for it and then I can enjoy driving it for a while.
Future plans include respraying the car, undersealing it and building the VVT block I have in the garage. Haven't decided whether to go full blown forged or if I can just get away with the minimals for changing to forged rods. I don't want crazy power, but reliable use would be excellent.
Probably the only acceptable time a 2 year old thread will be bumped on MiataTurbo.net.
Looks like you've been very busy with your build. I like the NB interior pieces, and the gauges. The mix between the new gen dash and the retro door panels is great. ID1000's... You doing E85?
I highly recommend at least doing rods if you're going into the bottom end, but if you do that you may as well do the pistons as well. Cheap insurance the way I see it.
Looking forward to this build playing out. Glad your back and posting.
Heh... There's a lot I've missed out of my update to be honest.
I'm going to try and keep this thread updated from now and join in a bit more in the community on here, it's a great place for info.
Forged rods were a minimum of the build, but I don't know how far to take the bottom end. I only ever intended to build something that could reliably make the most of the GT2560R that's with the kit. I can't see me going for a bigger turbo than that to be honest... but as they say, never say never!
Other plans, dump the power steering and fit a manual/depowered rack. I've not been a fan of PAS on this car, my old one felt better to drive and that only had a manual rack.
Also looking to upgrade to COPs of some description, I know the Toyota coils were popular at one point but now it seems people have moved onto better things, S2000 ones IIRC?
Aesthetically it would be nice to get a ducktail for the bootlid and maybe a GV rear panel and lights.
We originally were using Toyota Cops, now we have mostly switched to using LS coils. They are a good bit stronger spark wise, and relatively cheap, at least in the US. Several vendors are now also selling brackets for the coils, along with spark plug wires.
We originally were using Toyota Cops, now we have mostly switched to using LS coils. They are a good bit stronger spark wise, and relatively cheap, at least in the US. Several vendors are now also selling brackets for the coils, along with spark plug wires.
I'll have to see if I can find a seller in the UK. If not... I guess I'll have to look at importing some. If that is going to work out too expensive then I guess I'll have to rethink.
I opened up the throttle this morning as I'm confident everything is installed and working as it should.
I'm seeing it boost creep after about 4500rpm. Actuator I think is 9psi or so, but I crept up to 14psi where I had to back off before I blow the engine.
A lot of searching online suggests many people have had this problem with a GT2560R, I don't understand why FM sell this turbo with the kit if it's such a ballache. I didn't really see any proper solutions online, some were porting them, fitting cats, etc, but I don't think I actually saw a solution to this problem.
Has anyone here resolved a boost creep like this with an internal wastegate?
I've looked for externally wastegated turbine housings but they appear to be limited to Vband rather than T25 fitment.
Is that genuinely the only option? I've seen some pictures of some porting. I imagined it would be enlarging the outlet, but they seemed to leave that alone but rather remove material from inside leading up to the wastegate. Seems like a scary thing to be doing with a brand new turbo!
Seems like that's the thing to do... I notice he only suggests removing metal from the lead up to the port. Do you not need to enlarge the outlet itself?