MEP, ITBs, hillclimbs and trackdays

[baconsarnie]

That's pretty much the face I made when I rolled it out of the garage to take a look at it

[baconsarnie]

Update!



More turmpet. Hopefully more is more and the hard work to make this happen will be worth it when I have the map checked at Blink in a couple of weeks time. If the internets is to be beleived this change in intake length could yeild 7% improvement in torque at 7000rpm. We'll see.

Part of the plan has been to fit a brake bias adjuster. Stock the NA is setup with massive front bias. There should be some scope for increased braking by adding some bias to the rear. The re-plumbing required here gave me the opportunity to change the routing to give more room around the ITBs. More room means the possability of using some longer trumpets that should bring the 2nd wave harmonics (or some other science) down from 8000-8500rpm to 7000-7500rpm which should give a boost in torque.

They also look pretty cool.

Close up of the clearance now... Still tight around the clutch resevior but no different to the 40mm trumpets really.



Finally all assembled with the new larger pipercross filter:



Track day booked at Castle Combe end of Feb so need to get ready for that. Hopefully all the winter work has made MEP even better

[minty]

Lots of wants from me. Looking sweet!

[Ptichka]

Looks awesome baconarnie!

Would you be able to be a hero and tell me a few dimension?
What length are the trumpets? Are the Jenveys the 118mm long ones? Which size filter backplate is that?

[baconsarnie]

Thanks!

The Jenveys are whatever they supply as the 42mm dia 1600cc kit. Next time I'm out there I'll run a tape over them.

Trumpets are Jenvey 42x90mm (up 50mm over the ones supplied in their kit)

Not sure on back plate - whatever came with the kit. Note the holes are heavily offset toward the front of the engine for the (minimal) clearance to the clutch cyl.

Filter is Pipercross C604D (150mm deep)

Hope that helps!

[atlex]

That's a great distance to have between the trumpets and the inside of the filter. Bet it'll perform well !

[atlex]

(FYI I also had a huge pita fitting my ITG filter on mine, because of how close our clutch reservoirs are) Had to take a craft knife to about 15mm of material.

[Ptichka]

It's a right pain trying to size things up when you've got no access to the car, so that's super helpful thanks!
Jenvey list both 90 or 118mm long bodies, looking at the pictures they look nearer 90.

Like you IAT sensor location as well, looks neat

[baconsarnie]

Think you could be right on the length from the pictures.. I will check though!

Can't take credit for the IAT unfortunatly - there from when Blink origionally installed this setup on Matt Scarbros white car. Think you're right though, looks neat

[howardb66]

Looks really great, what championship are you going to compete in?

[baconsarnie]

HSA class 2A. Not the mx5 specific class as I think the rules are a bit mental! Are you competing this year?

[baconsarnie]

Feb 9, 2017 0:16:58 GMT Ptichka said:

It's a right pain trying to size things up when you've got no access to the car, so that's super helpful thanks!
Jenvey list both 90 or 118mm long bodies, looking at the pictures they look nearer 90.

Like you IAT sensor location as well, looks neat

Been out tinkering on the car today and have measured tge throttle bodies. 118mm 👍

[Ptichka]

Thanks a lot!

[baconsarnie]

So an interesting result... -1hp!!

But that isn't the story really. The peak power has moved 1000rpm down the rev band and it's basically making more power and torque everywhere up to 5500rpm where it just sits at the new peak to the red line.


(Hub figures - x1.3 for conservative fwhp estimate or x1.4 for "Autotronix corrected")

Can't say that I'm unhappy - this was an experiment after all - but it is interesting! Basically I've run out of cam and or compression/flow at the top end now. So the development plan has got to be some hotter cams (still on the mild piper regrinds bear in mind) and then hit the head up with some more serious modification (currently just a 35-40tho skim).

Next up was a shakedown track day at Castle Combe in preparation for the season opener "Great Western Sprint".

Morning was plagued by a misfire which only seems to manifest itself on track. But the afternoon sessions in the wet the car behaved and manged to get some pretty cautious laps in. Pics and vids below:

[sandys]

Feb 9, 2017 13:43:30 GMT baconsarnie said:

HSA class 2A. Not the mx5 specific class as I think the rules are a bit mental! Are you competing this year?

We will be competing together then I am also doing the Great Western Sprint, though you will be in A2 for that and I'll be in A3 as I have a 2.0, I am also doing the HSA again.

HSA class A2.1 for Mazdas hasn't got any mad rules, unless you consider List 1A tyres mad? Your car would be perfect for that class from what I can see, it is not restrictive like BMC MX5 or Gurston MX5 classes. Its only stipulation is that you are a roadgoing Mx5 and on 1A tyres.

I took that class last year competed against some nice 5 owners, it was a good crack.

I am doing A2 this year as I have never run 1B rubber so I thought it was time to have a go.

Castle Combe have put some horrid tyre barriers up, that basically makes it a different track to last year, I wonder if HSA will reset the records? The tyre barriers look potentially dangerous.