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aidandj 07-03-2018 08:48 AM

I might be slightly biased, but I say 6758

https://cimg2.ibsrv.net/gimg/www.mia...526feab972.gif

sixshooter 07-03-2018 08:50 AM

External wastegate adds a level of complexity to the downpipe. I haven't had any issues with the Garrett turbine housing with internal wastegate. What is your reason for not considering it?

LTurner1 07-03-2018 09:05 AM


Originally Posted by aidandj (Post 1489580)
I might be slightly biased, but I say 6758

https://cimg2.ibsrv.net/gimg/www.mia...526feab972.gif

Ha! we'll see... like I say, it's quite a big difference in cost to go for an EFR, so much so that it nearly covers the entire cost of my custom manifold.


Originally Posted by sixshooter (Post 1489583)
External wastegate adds a level of complexity to the downpipe. I haven't had any issues with the Garrett turbine housing with internal wastegate. What is your reason for not considering it?

I dunno whether they're all as bad, but I had to port the wastegate on my GT2560R to solve a boost creep issue with an internal wastegate and that sucked.

aidandj 07-03-2018 09:06 AM

Efr doesn't need wastegate or bov. Remember that.

LTurner1 07-03-2018 09:11 AM

I really like this kind of design:

https://cimg1.ibsrv.net/gimg/www.mia...d0c7ae153c.jpg

But I'd be wanting to link that screamer pipe back into the downpipe as I do eventually intend on the occasional track day in this.

aidandj you do raise a good point. I'm still debating what to do... I suppose first thing I should do is sell up what I have so I know what funds are available.

LTurner1 07-12-2018 06:21 AM

Starting to really consider a GTX3071R as well now, going to continue doing some more research... Maybe I'm getting too silly.

LTurner1 07-16-2018 03:03 AM

My AWR mounts from Fab9 should hopefully turn up this week, I'm also on the hunt for a front subframe with wishbones so that I can have it blasted, powder coated and bushed ready for the new engine. I'm aiming to rebuild the front end, underseal it all etc whilst the engine swap happens. And then when I have chance I'll do the same with the rear. The parts are cheap enough it's just having the time to go and collect them.

Happened to see this beauty whilst I was out and about for my birthday:
https://cimg7.ibsrv.net/gimg/www.mia...55966ca86e.jpg

Talking of my birthday... I did my first solo flight the morning of it. I'd say there was an equal share of excitement and terror ha

https://cimg3.ibsrv.net/gimg/www.mia...da25cb2313.jpg

I think that's all for now, other than me still trying to figure out what turbo to go for. I've read a lot of threads on here and had a browse through most of the spool data thread. I'm still leaning towards a GTX3071R after all that, I think it'll be a good compromise between reasonable spool and sensible power goals. A bit unsure on A/R choice though.

-Lew

sixshooter 07-16-2018 07:20 AM

A/R choice would depend on your redline, fuel choice, and a couple of other factors, imo.

A larger AR will certainly give you later spool up on what is already a large Turbo. If you plan on running 8000 RPM then maybe you have enough operating range not to fall out of boost every shift. A larger AR offers a little less back pressure, but that's probably not a big deal on a turbo that big. Increased back pressure will create more heat and possibility of detonation at the same power levels but again not probably an issue on that size.

If I was going to run a GTX30xx I would likely look at the larger compressor size really closely. 76R will actually flow more pounds without probably a tremendous shift in the surge line. You'll need to look at it.

All of that being said, I would run a smaller AR with that turbo and keep my red line 7200 for longevity. .64 or something.

Why not EFR?

LTurner1 07-16-2018 07:37 AM


Originally Posted by sixshooter (Post 1491595)
A/R choice would depend on your redline, fuel choice, and a couple of other factors, imo.

A larger AR will certainly give you later spool up on what is already a large Turbo. If you plan on running 8000 RPM then maybe you have enough operating range not to fall out of boost every shift. A larger AR offers a little less back pressure, but that's probably not a big deal on a turbo that big. Increased back pressure will create more heat and possibility of detonation at the same power levels but again not probably an issue on that size.

If I was going to run a GTX30xx I would likely look at the larger compressor size really closely. 76R will actually flow more pounds without probably a tremendous shift in the surge line. You'll need to look at it.

All of that being said, I would run a smaller AR with that turbo and keep my red line 7200 for longevity. .64 or something.

Why not EFR?

Thanks for the input! I'm still open to the idea of an EFR, I've by no means discounted it. However, here in the UK the prices seem fairly insane for one.
I got quoted £1880 for an EFR6758 with T25 turbine housing. That's roughly $2,497.68...
Maybe I'm missing something, but the Garrett options are cheaper for me, I could probably get the GTX for around £900-1000. If I ordered an EFR from the US then I'd have to factor in a hefty import duty and tax to pay on it.

-Lew

sixshooter 07-16-2018 07:53 AM

That makes sense.

I had a Chinese 2871 copy and it spooled fine to 12psi with the .86 housing. I can't tell much spool difference with the GTX2867R and .86 I have now. I make a lot more power now than back then, though. A 2867 made enough power at 21psi to destroy my 6 speed (~320-330whp) and had the headroom to go higher, so unless you have a transmission solution planned I wouldn't be in a big hurry to go to the GTX30xx. You will have slower spool up and no room to gain on the top side for power because of the trans.

LTurner1 07-16-2018 08:36 AM

Yep, again, not sure what to do here.

I really REALLY want to get the K-Miata ZF swap kit. The robustness of it, combined with the longer gear ratios just seems perfect. However, again I'll be smacked with import duty and 20% VAT to pay on it, making it really expensive, and I don't see anyone here making a kit because the volume of orders would be significantly less than over there.

All I can hope for is that your tremendous* president and our tremendous* prime minister banged out a great trade deal. Until then I'll just have to run 6 speeds.

Another factor, I am considering track days too and I suspect I'd benefit from the cooler temps from a no-so-strained 30** than a 28**. But, as you say if a 2867R can turn a 6 speed into metal bits then maybe I shouldn't be looking at going any bigger.

* not really tremendous

LTurner1 07-19-2018 04:18 AM

Another piece of the puzzle arrived from the US

https://cimg2.ibsrv.net/gimg/www.mia...e2fe377792.jpg

I've found an NA front subframe and wishbone setup fairly local to me that I will hopefully collect soon. Plan is to blast and powder coat the metal, get myself some new hubs, etc, I want everything to be fresh and new. Any recommendations on bushes? it seems to be a hotly debated topic over here, I'm quite tempted to just replace with OEM, heard very mixed reviews about pretty much all polybush kits.

-Lew

LTurner1 07-20-2018 11:07 AM

Machining work pics... rods and pistons balanced to within 0.1g

https://cimg1.ibsrv.net/gimg/www.mia...fd2d9d36f1.jpg https://cimg2.ibsrv.net/gimg/www.mia...ef1e32efb9.jpg
https://cimg5.ibsrv.net/gimg/www.mia...402ac3f118.jpg

-Lew

Oscar 07-20-2018 11:19 AM

Nice, is AK doing your engine build?

LTurner1 07-20-2018 11:22 AM


Originally Posted by Oscar (Post 1492338)
Nice, is AK doing your engine build?

Yup.

LTurner1 07-23-2018 03:51 AM

A couple more updates.

Finally got chance to sort through my bombsite of a garage, managed to organise everything, bag loose bits up and label them. Cleaned every spanner and socket and got my wife to size order them, winner! Another winner was finding a whole load of stuff I forgot I owned and decided to put up for sale, and overnight most of that has already sold, pending collection.

I needed to do this in preparation for the engine returning, as I'll need somewhere to build the remainder of it.

In two weeks time I am collecting this lot:

https://cimg8.ibsrv.net/gimg/www.mia...4c1a6255b9.jpg https://cimg0.ibsrv.net/gimg/www.mia...2028d54764.jpg
https://cimg1.ibsrv.net/gimg/www.mia...acc6962acd.jpg https://cimg4.ibsrv.net/gimg/www.mia...87f3cdca74.jpg

Refurbished and powder coated subframe/wishbone set. I did plan to do this myself, but a whole set came up and now me and the wife will be spending a weekend in Cambridge when I collect them.

This makes things much easier for me now, as soon as I'm free (possibly our August bank holiday weekend) I am going to whip the engine out, take the subframe off and begin undersealing the front section of the car. I need to look at ordering some poly bushes, new hubs etc. I also need to get my hands on a depowered steering rack too. Aiming for a full rebuild under the car inline with the engine build. I've not had a show car for 4 years now and I'm itching to get back to that level. But also to own something that will decimate all.

-Lew

BBro 07-23-2018 08:53 AM

Really cool build thread. I like all the planning and attention to detail, I’m sure the end product will be worth it.

LTurner1 07-30-2018 08:25 AM


Originally Posted by BBro (Post 1492727)
Really cool build thread. I like all the planning and attention to detail, I’m sure the end product will be worth it.

Cheers! It's going to have cost me a fortune this build, but I really wanted to make this car standout to those with a keen eye. The plan aesthetically are to keep it subtle, again, those with a keen eye will pick up on the sticky tyres and Wilwoods, but other than that, it's mostly plain looking these days.

I began taking parts off the car on Friday night, I'd already agreed a sale on the GT2560R so I needed to remove that, and I also finally decided that I'm gonna sell the FM hot side setup in favour of a custom tubular setup.

Pretty much decided on a Gen 2 GTX3076R 0.83 A/R VBand turbo for the build, I have absolutely no doubt that this car is going to terrify me as much as it excites me.

Having removed some bits from the car it's made me realise what a cruddy state it's in, but thankfully most of the cruddy stuff is being replaced with new shiny parts, I'm undecided on whether to spray the engine bay a different colour to the car. Maybe a satin black or something so the engine can stand out some more.

Collecting the powdercoated subframes and wishbones this weekend, as well as some frame rails. So I'll definitely need to crack on with stripping the car down soon in order to begin prepping the underside of the car against our crappy salty roads. That said, I don't think I'll ever drive this thing in the rain/snow/ice again in order to help protect my hard earned!

Here's a few pics of Friday nights work:

https://cimg0.ibsrv.net/gimg/www.mia...24e923a831.jpg https://cimg3.ibsrv.net/gimg/www.mia...8a05a50359.jpg
https://cimg5.ibsrv.net/gimg/www.mia...7a5153bc27.jpg https://cimg7.ibsrv.net/gimg/www.mia...bc8906aaa4.jpg

-Lew






borka 07-30-2018 10:28 AM

I bought an efr6258 t25 for $1264 brand new.
I would imagine even with $150 shipping and 20% VAT it's still a lot less than the prices you were quoted.

I went from a 2560r to 6258 and the difference is very significant, more power and much faster spool up between gear shifts.

I recommend you rethink the turbo selection.

LTurner1 07-30-2018 10:32 AM


Originally Posted by borka (Post 1494068)
I bought an efr6258 t25 for $1264 brand new.
I would imagine even with $150 shipping and 20% VAT it's still a lot less than the prices you were quoted.

I went from a 2560r to 6258 and the difference is very significant, more power and much faster spool up between gear shifts.

I recommend you rethink the turbo selection.

Where did you buy from?

It's looking around £1300 for the GTX3076R option. Your 6258 would probably come in around the same as that all costs considered, but I'd prefer the 6758 I think, I really do fancy having the headroom for more once I get look at getting the ZF box swap or similar.

-Lew


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