Selene - Nev's NB SE

Nevyn72 · Postby **Nevyn72** » Sun May 01, 2016 1:49 pm

I seem to be having a conversation with myself here...... So I might as well finish it off.

Took the car out for a longer drive today and the BOV noise is not as loud/obnoxious as I remember it from last night.
It is also far less frequent and intrusive when you're not constantly trying to provoke it. :oops:

As for power, it definitely has quite a bit more, more than I thought last night.
On sections of road I frequently travel, where in the past I would have dropped back to 5th gear it now travels quite comfortably in 6th. Overall it also seems more responsive with the biggest gains in power from around 3000RPM upwards.

Boost now also appears to be peaking at around 8.5 PSI rather than 7.5 PSI previously (factory setting).
I wonder why this is as I'm still running the factory EBC. It's not boost creep as it doesn't keep rising.

In the end what did I actually do?
Well effectively I replaced the bit of Intake pipe between the MAF and the turbo inlet elbow.
Previously = 102cm + 9 bends
Now = 22cm + 2 bends

There were some changes to the airbox but these would probably have negligible effect.

In terms of what I have now, it's comprable to the AEM or Nitro Dann setups. Similar in length with the same number of bends (although those systems have straighter bends than mine) with the main difference being that they use Pod filters while I'm still running the factory panel filter (smaller surface area?) albeit probably the last 'high-flow' SE specific filter from Mazda in the country.
It's certainly shorter and straighter than other options like the Flyin Miata, Joe's and BEGI, but they also use Pod filters.

Overall I'm very pleased with the result from what was a highly experimental and speculative project and it's certainly unique! :mrgreen:

Now what to do next? :wink:

smy0003 · Postby **smy0003** » Sun May 01, 2016 2:17 pm

I'm following, 100 stealth points to you for this.
Not surprised that the bov is more audible with the more open intake, I like that sort of thing, but then again I'm pretty juvenile hahaha.
I'm sure you'll get used to it, you'll probably start to really dig it.

Sent from my LG-H815 using Tapatalk

Postby **Okibi** » Sun May 01, 2016 4:19 pm

Nevyn72 wrote:...Boost now also appears to be peaking at around 8.5 PSI rather than 7.5 PSI previously (factory setting).
I wonder why this is as I'm still running the factory EBC. It's not boost creep as it doesn't keep rising. ..

A lot of MSM owners talk about the wastegate flow being in efficient once the car can breath better. Could be a case of not enough exhaust bypassing the turbine wheel and thus creating more boost.

Nevyn72 · Postby **Nevyn72** » Sun May 01, 2016 6:12 pm

Okibi wrote:
Nevyn72 wrote:...Boost now also appears to be peaking at around 8.5 PSI rather than 7.5 PSI previously (factory setting).
I wonder why this is as I'm still running the factory EBC. It's not boost creep as it doesn't keep rising. ..

A lot of MSM owners talk about the wastegate flow being in efficient once the car can breath better. Could be a case of not enough exhaust bypassing the turbine wheel and thus creating more boost.

Doesn't this become a positive feedback situation leading to steadily increasing boost, ie. classic boost creep?

I though it might have had something to do with how the factory ECU / EBC measure and regulate boost levels.
Given there is no MAP sensor, I thought they might be 'calibrated' somehow for the factory intake and freeing this up throws that calibration out resulting in a higher boost level....

So long as it doesn't cause any issues I'm happy to leave well enough alone and just enjoy the bonus 1 PSI of extra boost! :mrgreen:

Lokiel · Postby **Lokiel** » Sun May 01, 2016 7:57 pm

Nevyn72 wrote:I seem to be having a conversation with myself here...... So I might as well finish it off.
:

I'm actually most impressed that you managed to get the OEM rubber elbow (far left in photo) off the turbo in one piece.

I spent hours trying to get that off and in the end resorted to a non-reversible Stanley knife solution - mine was fused onto the turbo, it was never going to come off cleanly.

Re-use of the OEM TB elbow was inspired and certainly preserves the OEM look - always good to see alternative approaches, especially when executed well.

Nevyn72 · Postby **Nevyn72** » Sun May 01, 2016 10:40 pm

Lokiel wrote:I'm actually most impressed that you managed to get the OEM rubber elbow (far left in photo) off the turbo in one piece.

Re-use of the OEM TB elbow was inspired and certainly preserves the OEM look - always good to see alternative approaches, especially when executed well.

Small confession, the OEM rubber turbo elbow in the image isn't actually from my car, it's one I bought second hand from Emily when sourcing some bits..... :oops:

The one on my car is still there, I didn't even try and remove it due to reports like yours about how difficult it was to get off intact.

Because I wanted to keep the ability to revert to OEM if I wasn't happy with the result I was forced to source all the bits for this build second hand.
As it turned out that wasn't very much, most of the OEM SE noodle (courtesty of Emily, minus the one bit I actually wanted, the outlet pipe) and a conventional NB airbox and snorkel. From the SE intake noodle portion I actually only ended up using a tiny bit of 20mm metal pipe. :roll:

As for the OEM TB elbow, well that was a moment of whimsy followed by abject astonishment that it fitted the MAF outlet perfectly! :mrgreen:

speed · Postby **speed** » Mon May 02, 2016 9:36 am

Great work - perfect results!

Nevyn72 · Postby **Nevyn72** » Mon May 02, 2016 1:23 pm

speed wrote:Great work - perfect results!

Thanks Steve. :mrgreen:

I went for a scamper through Nasho today, a noticeable difference on one of my favorite haunts, I'm even getting used to the more talkative BOV.........

Roadrunner · Postby **Roadrunner** » Mon May 02, 2016 5:49 pm

That looks really good! Great stuff!

Nevyn72 · Postby **Nevyn72** » Tue May 24, 2016 3:45 pm

A beautiful Autumn day, the sun is shining, everyone else is at work, I've got a token day off = Time for a drive! :mrgreen:

Nevyn72 wrote:Boost now also appears to be peaking at around 8.5 PSI rather than 7.5 PSI previously (factory setting).
I wonder why this is as I'm still running the factory EBC. It's not boost creep as it doesn't keep rising.

I will now officially take this back. :oops:

A combination of the new freer flowing intake plus nice cold morning air means that boost is peaking at 9+ PSI and on sustained runs I'm getting boost creep up to ~11 PSI.
I was wondering why the car was feeling so frisky on the first part of the drive......
I'll need to keep an eye on this as the only thing that will fix it is an ECU + MAC valve replacement.

On the plus side, I really like the extra power!

So, what else is going on?

Well, for those that were following the build before the great forum catastrophe of 2014 when all the photos were obliterated, you would remember that I spent quite a bit of money on all manner of shiny bits from overseas. Not cheap either.
So I was more than a little disappointed that one of the main bits, the chrome gear surround, started flaking around the edges of one of the bolt holes..... German rubbish! :evil:

The solution?

Find the genuine Oriental piece from the factory..... Which are of course as rare as unmodifed MX5's on this forum.

So you can imagine how surprised I was to score one the other day before Richard (bear) snapped it up, I mean it was online for 12 minutes before I spotted it.
He must have been busy staring at his CF bonnet he's going to sell me when he's sick of it. :wink:

The bonus was I got a complete centre console with it, something else to add to the spares pile I suppose.

That looks a lot better!

I ended up deciding to use the silver bolts from the IL motorsports surround rather than the black ones from the factory.
Partly because two of the factory one were slightly rusty (easily fixed I know) but mainly because I preferred the look with it being silver.

So what's the next project?
Could be to finish the power side of the equation (ECU, MAC valve, injectors & Dyno tune)
Could be suspension
Could be something cosmetic
Clutch and rear main seal will need to get done sometime

I'll just start collecting parts as they become available and see what I feel the urge to do first is.....

Speaking of collecting parts, these came in the mail the other day. :mrgreen:

ManiacLachy · Postby **ManiacLachy** » Tue May 24, 2016 3:57 pm

I'm very happy to see Selene is getting some love once again. That new gear surround looks great, better than the (I assume) I.L. Motorsports one.

Have you hit boost cut yet? It's not pleasant.

Nevyn72 · Postby **Nevyn72** » Tue May 24, 2016 4:02 pm

ManiacLachy wrote:Have you hit boost cut yet? It's not pleasant.

Boost cut?
No.

The rev limiter on the other hand....... :oops:

ManiacLachy · Postby **ManiacLachy** » Tue May 24, 2016 4:09 pm

Nevyn72 wrote:Boost cut?
No.

The rev limiter on the other hand.......

That too can be addressed with an ECU :mrgreen:

KevGoat · Postby **KevGoat** » Wed May 25, 2016 10:21 pm

Nevyn72 wrote:The solution?

Find the genuine Oriental piece from the factory..... Which are of course as rare as unmodifed MX5's on this forum.

So you can imagine how surprised I was to score one the other day before Richard (bear) snapped it up, I mean it was online for 12 minutes before I spotted it.
He must have been busy staring at his CF bonnet he's going to sell me when he's sick of it.

Nah ... Richard's not that slow :mrgreen:

... he'd already bought my "Roadster" surround - from my NB8A "SE wannabe" :wink: