PeterB - Evo Gold NB8A

[greenMachine]

Too bad Peter. Baffled sump, and run a higher oil level, my tip of the day. You can buy me a coffee, no need to pay .

If you end up needing one, I might know where you could find a good short motor, no guarantees on the rods though ... but it will cost you more than a coffee



Actually, now that I think about it, I know where there are three good forged rods, and one that might benefit from a crack test ...

[PeterB]

Thanks

The other green machine (Mr V) has just had a re-built motor fitted by Carco, must be a trend, so there are a few spare cranks around if mine doesn't measure up.

If all measures up Carco will do a stock re-build to keep within the Clubman regs.

The oiling set-up should manage Wakefield on street tyres, with stock rev limit as long as I keep the oil up to it !!!!

My last two 1600s were stock bottom ends with shimmed up oil pumps, with Fanta running to 8,400 rpm with no problems as they were always over-filled with oil

But, big compression, forged rods, ecu, head, cams, exhaust - no stop it !!!!!!!!!!

[PeterB]

The final part of the puzzle has been revealed - the front of the sump has been welded to repair a hole. The car also has evidence of a small front end repair.

Guessing - left road with front left and hit a rock or other object holing sump. Gearbox and sump removed, sump welded and re-fitted. Gearbox re-fitted leaving out two top bellhousing bolts (too hard to fit) and replaced lost rear mount bolt with dodgy nut and bolt. Then sold on quick !!!

How long was it run after sump holed, etc ??

Next lady owner used is a daily and it probably never got a rev and was very happy with it.

I then got it and flogged it around Wakefield with oil level low and goodbye big-ends.

Conclusion : no inherent design or component faults, just a series of user errors culminating in the rebuild.

The engine is now rebuilt to stock specifications by MX5 Solutions (Carco) and Belconnen Engines.

Crank grind 10 thou, race bearings, new oil pump, hone and rings, head service, Exceedy heavy duty clutch and front gearbox seal.

200 km and it feels good with no leaks, so off to run it in.

[PeterB]

Took the opportunity while she was off the road to fit a braided clutch line to replace the messy mazda set-up.

Also fitted the braided brake lines I bought at the auction in Berrima a few months ago, so some improvements made.

Will be a while before she hits the track while I re-build my racing budget and get her well and truly run-in. Probably a few hillclimbs first to get her used to the idea.

[Guran]

Thanks for the update. Looking forward to seeing you back on the track.

[Blesif]

You have certainly given a few of us a wake up call re engine oil level. Both Greg Unger and I decided to measure how much oil drained out during service a month or so ago. Interesting. The dip stick on both cars said just below full but only 3L drained out and that included the filter! Very dodgy as I have run several track days like that. We both carefully measured the new oil going in and ignored what the dip stick said. Greg went the whole 3.8L as per handbook and I put in 3.6L. Needless to say the dipstick read overfull on both cars. I intend to add some before Wakefield on the 14th but ran no problem at SMSP last weekend. Does anyone else out there find the dip stick difficult to "read" accurately? I have an NB8A.

My son tells me the Nissan boys always overfill and they don't blow seals. Is the same true for Mazda?

Looking forward to seeing you back on the track, Peter and thanks for the report on what you have found during the rebuild.

[Apu]

I always wonder if 100% of the oil drains out but that said, I've always overfilled - partly because of the oil cooler which is mounted high on the MX5, but also do the same in the Integra.

I was advised to add perhaps 500ml even if the the dipstick read full by one of the ATCC teams when we used to do track days in Malaysia.

[RS2000]

We both carefully measured the new oil going in and ignored what the dip stick said. Greg went the whole 3.8L as per handbook and I put in 3.6L. Needless to say the dipstick read overfull on both cars.

Same with my NB8A & just about every car I've owned.
I always pour in the handbook volume on the first oil change of a newly aquired car, then mark the dipstick to suit. Not what the handbooks say to do, but I've never had a problem, even with track cars.

Cheers

[greenltd]

This will sound silly, but i always reckon i drain less than I put back in, with the dipstick showing full before and after.

When competing i always add some extra oil for security.

Also i seem to have oil at different heights on opposite sides of the dipstick when checking the oil level.

[PeterB]

Well it is now 12 months of ownership and time to reflect.

A cheap NB8A, became an expensive one with a rebuilt engine and new radiator, but should now be as good as new (I hope).

As she sits in the driveway today :

Engine rebuilt to stock specifications by Carco and Belconnen Engines, with quality bearings and new oil pump.
New radiator, hoses, water pump and cam belt.
2nd hand Bilstein shocks.
Torsen 2 diff (4.3:1) from Britney.
Hawk HP+ front pads
15x6.5" rim with Dunlop ZII for a 1.16.12
15x7" rims with used Yokohama A050 for a 1.15.2.
Sparco Sprint V seat on NA rails, 6 point harness, Brown-Davis roll bar from Britney.
Tow-bar/bike rack.

If I had not previously competed in the NA6s I would be very pleased with what I have, but I much prefer the feel of the NA6 on track.
The NB8A is a much nicer road car, including a/c, so on balance the upgrade was worth it, but each time I drive into Wakefield I wish I was in Fanta or Britney with their lively little 1600s and precise feeling on track.

[david_syd_au]

Peter,

I just want to make sure you know, the braided brake lines are not on the list of allowed modifications for the Clubman class, unless you know of an NA or NB model that came from the factory with braided brake lines?
http://nsw.mx5.com.au/motorsport/track-days/classes/clubman

The braided clutch line can be justified as a non-performance mod.

Regards
David

Also fitted the braided brake lines I bought at the auction in Berrima a few months ago, so some improvements made.

[PeterB]

David

Thanks. I didn't think and just assumed that ADR approved braided brake lines would just be a safety upgrade, but this is of no consequence as I will gradually be setting the car up for Type 2B specs for the local hillclimb and supersprints, so she will fall into the modified class in future MX5 trackdays. I can then run on Nittos as they are cheaper (and quicker) than ZII Dunlops.

In hindsight, an early NB8A is outperformed by the NB8B, and if I was to continue to chase the Clubman class would swap over to one of those.

[Okibi]

...assumed that ADR approved braided brake lines would just be a safety upgrade...

I'd have thought the same, encouraging members to replace old worn brake lines would be more beneficial than any tiny advantage you could potentially get from braid.

[david_syd_au]

I agree that old brake lines should be replaced for safety, but while there are OEM spec rubber lines available new, they should be used by drivers who compete in the MX-5 Club of NSW standard and clubman classes.
If the day comes when rubber replacement lines are not available, then the class rules should of course be re-evaluated.

...assumed that ADR approved braided brake lines would just be a safety upgrade...

I'd have thought the same, encouraging members to replace old worn brake lines would be more beneficial than any tiny advantage you could potentially get from braid.

[PeterB]

A very quiet year on the motorsport front following the engine rebuild, with the only run being at the Wakefield Park 2015 Australian Supersprint Championship.

A 1.15.2 was slower than I hoped, but acceptable in the mixed conditions and on very tired Yokohama A050s (2nd hand IPRA set I got for $50) and I had a heap of fun on track.

I came home with a 3rd in class 3B (after some classification issues) and the trophy looks nice on the shelf.

The Xmas present for the NB8A was a set of NB8B seats from one of greenmachine's wrecks. Being tall, the gap between the top of the NB8A seat and the Brown Davis roll bar was a bit too large for comfort in a rear ender, whilst the NB8B seat reaches to the bar and is a much better head rest. Will need a foamectomy in due course.

At Wakefield I got a fuel surge through the fishhook, although the tank was 1/2 full. A check by Carco showed that a replacement fuel pump, fitted for the previous owner by a mobile mechanic service, was installed with the filter on the end of the pump twisted the wrong way and reducing pickup. This is now rectified by Carco and she is ready to go.

Heading off to Phillip Island for the fantastic Classic Car Races on 12/13 March (supposedly a full field of F5000 !!!) then a tour of country Victoria (in a Falcon with caravan in tow - so not a driving tour).