What have you done today/recently to your 5?

[MonkeyBritchers]

Swapped the gauges for Revlimiter JNCs, Jass Performance independent deep rings and needle caps bought on Yahoo Auctions Japan for the princely sum of 1 yen.

[Lokiel]

plohl - I was about to bitch about how mush hassle it is install a QMax coolant re-route while the engine is installed (doing it now and am on a break).

Thanks, you've made me feel better.

PS: If you do want to do the QMax coolant re-route with the engine still in the car, start by ripping out everything back there, you CAN'T work around it, there's very little room!

[plohl]

PS: If you do want to do the QMax coolant re-route with the engine still in the car, start by ripping out everything back there, you CAN'T work around it, there's very little room!

Oh yeah man! Nick and I are building a replacement vvt engine for his car and will do the reroute whilst it's out of the car. Hope you get it together alright!

[Lokiel]

Which re-route kit are you using?

The FM kit is better because it routes the coolest water through the turbo, QMax routes it after it has been run from the back to the front of the engine.

After watching the FM installation guide I realised there was no way in hell I wanted to install it, their rear block is bigger, way too much plumbing back there which is already crowded and my existing TSE EFR6258 stainless steel water lines look too "cool" to replace.

I used a real gasket on the block rather than using the gasket-maker provided by the QMax kit - I knew it was going to take a LONG time with multiple attempts before I'd get it installed. Not sure how long the gasket maker takes to cure but I knew it would end up coating everything as I fumbled it blindly into place and got the nut and bolt on. The rear/lower nut was surprisingly easy to get on and tighten thankfully - the top bolt was MUCH harder, partly because the hose was now pulling it away.

I put the large hose on the block before installing it since some people reported that it was nearly impossible to fit after the block was installed.
This also helped because it prevented the block from falling down behind the engine (like all my spanners and sockets did).
Twisting the hose helped orient the block while I worked from the other side of the engine since the block stayed in place.

I didn't complete the job but got the block fitted so will finish up tonight.

That white clip on the firewall REALLY p i s s e d me off when removing the original block, I could barely get my hand/arm in there in the first place and it was in the perfect position to shred my hand and wrist as I worked blindly to remove the rear nut and bolt:



View from the other side:

[plohl]

Great pictures!
He was leaning towards the qmax kit.
Yeah, I looked at the FM kit as well and agree it looks pretty sh*t to install. I like how the qmax has a circlip for the thermostat.
Keen to hear how it bleeds up when you get it finished!

[greenMachine]

I've got one too, but it is still on the shelf. Was thinking it might have to wait till the rods get done, but when the heater core gets replaced that might give me a bit more room to play with ...

[Lokiel]

I kicked myself for not getting the 180*F (82*C) thermostat after watching a youtube guy in Arizona was using one in his setup due to the heat in Arizona - Supermiata supplies the 195*F (90*C).

I'd replaced the OEM one at the front with a 78*C version years ago since QLD gets bloody hot in summer and had forgotten about it.

I've ordered a couple of 180*F thermostats from Jeggs since S&H was more than the cost of a single unit (unfortunately I couldn't think of anything else I needed) and will redo it on the weekend (if anyone wants an 180*F thermostat for the Supermiata housing, let me know and I'll split the cost with you).

I'm still doing a few other modz in the engine bay so temporarily hooked up the water lines for a leak test - and found the rear leaked

I think I'll just use a gasket rather than the provided sealant on the rear, it had probably cured too much or had gaps formed by the time I'd managed to "fanangle" it into place, retrieve the spanners/nut that dropped through to the ground, and secure both the nut and bolt on the rear.

Probably just as well it leaked since I may have been tempted to just live with the warmer thermostat, it's a bugger to fit with the engine in place.

[RS2000]

I've often thought low temp thermostats are probably a con, even on race cars.

http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/

[StillIC]

My understanding of thermostat ratings is along the following lines, which disagrees with at least one major point of what tuneruniversity.com states.

1) In a vehicle with a 'big' cooling system in weather/ambient temperatures/operating conditions it was designed to operate within, the temperature of the opening of the thermostat sets a ceiling (not a floor) to the operating temperature of the engine. Once the cooling system is doing its job at the temperature at which the thermostat opens, why would the engine get any hotter? (See 3)
2) Conversely to 1, any car/engine with an insufficient (small) cooling system for the operating conditions will overheat, no matter what the opening temperature of the thermostat is, as the thermostat is unlikely to be the limiting factor.
3) Many (right sized) cooling systems are designed such that the engine will run hotter than the thermostat opening temperature and control upper temperature by using fans behind the radiator or other techniques. This is where tuneruniversity.com is arguably correct in its statement about the thermostat setting a floor on engine temperature.

Renowned tuner David Vizard suggests running cool thermostats in race cars to reduce the operating temperature of the engine, to reduce air intake temperatures for slightly more power. The down side of this is that the engine will produce more pollution, it will need a cooling system capable of maintaining that temperature (see 1) and the oil used in the engine will need to be appropriate for a change in the operating temperature to ensure reasonable viscosity, I imagine. I have done this with my MX5 road/track car.

So, in line with statement 1, my MX5 never overheats on the road. I am running a low temperature thermostat and the engine arguably doesn't get hot enough. The cooling system is easily capable of maintaining the engine temp below or at the thermostat opening temperature.

In line with statement 3, on the track (SMSP) on a hot day in summer, I have to unblank the oil cooler for added cooling as the standard cooling system on its own can't control the overall engine temperature adequately.

Having said that, I think in hindsight I should run a hotter thermostat so that the car gets to a reasonable operating temperature on the road. Perhaps I will lose a touch of power on cold days at the track, but it will make no difference to hot days at the track.

As always, horses for courses.

[davekmoore]

I've set fire to the NC and put number 2 and 3 rods out the side of the NB's block. As usual, the NA just keeps going.

[KevGoat]

Well ... last weekend, as MXSE is our "main" car lately, we drove a short way to Clarendon to the pub to meet friends for a birthday dinner. On the short drive from the pub to our friends' place after dinner, the car threw up a CEL P2096 Code: Post Catalyst Fuel Trim System Too Lean (Bank 1). Pulled over and switched off the car and then restarted, CEL still there, but the engine sounded fine. Drove the short distance to friend's house and popped the bonnet, used the phone torch and checked all the hoses and as much as I could. I didn't have my OBD tool with me, so at this stage, I didn't know what the code was.
Interestingly, on the way home, the car actually felt better than it had recently - I've had some inconsistent idling issues and some low-speed roughness.
The next day, I plugged in the OBD reader and got the code, and began the online searching. My first thought when it happened was the engine running too rich as I had changed out the BEGi short ram CAI for the stock airbox, but it was the opposite, too lean. After reading more, I then thought about the MSM rear exhaust manifold bolt coming loose... it's a known issue. So today, a bit cooler weather, I jack'd the car up and started checking everything. Removed the airbox so I could move the manifold heat shield, and yup, that bolt was loose! I then went all through all the exhaust bolts front to back and found a few slightly loose (these hadn’t been checked since fitting the NitroDann exhaust). Cleared the code and took the car for a drive, and the CEL hasn't returned, so fingers crossed this was the issue.

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[Lokiel]

^
"I had changed out the BEGi short ram CAI for the stock airbox"
Why on earth would you do that?
Don't like the additional noise?
Planning to sell?

Well done with the DIY research and, it pays to periodically check all the exhaust+manifold nuts&bolts are tight (and still present )

[KevGoat]

Just the noise Lokiel. I'd tried a few things - different filters, closing off the gaps around the airbox, lining the airbox, but it was still too intrusive, especially on the longer trips we do in the car. Obviously, there's a trade-off, but tbh I haven't noticed a great deal of performance drop-off, especially as I rarely rev high anyway. On the positive side, I have noticed a slight increase in torque down low, which I actually prefer (leftover style and preference from my old 6's and V8 days). Hey, I change my mind every five minutes, I'll probably be fitting it all back in no time!!

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[RS2000]

The next day, I plugged in the OBD reader and got the code, and began the online searching. My first thought when it happened was the engine running too rich as I had changed out the BEGi short ram CAI for the stock airbox, but it was the opposite, too lean. After reading more, I then thought about the MSM rear exhaust manifold bolt coming loose... it's a known issue. So today, a bit cooler weather, I jack'd the car up and started checking everything. Removed the airbox so I could move the manifold heat shield, and yup, that bolt was loose! I then went all through all the exhaust bolts front to back and found a few slightly loose (these hadn’t been checked since fitting the NitroDann exhaust). Cleared the code and took the car for a drive, and the CEL hasn't returned, so fingers crossed this was the issue.

I thought with an exhaust manifold leak, that the oxygen sensor thinks the engine is running lean (when it's not), so extra fuel is added giving an overly rich mixture?

[KevGoat]

Yeah, the sensor/code was showing lean. Probably the way I explained what I'd done made it confusing. The code would be sent up before the ecu adds fuel, I should think. When I found the code next day and searched online, most on Miata.net said this would almost always be an exhaust leak causing the sensor to see a lean reading, which made me think of the loose manifold bolt issue, which is pre cat, so along with the slightly loose downpipe nuts which are also pre cat, these could have all been part of the cause. It's probably also why the idling has been inconsistent of late, and I've had some surging at low revs. The other loose nuts along the exhaust were post sensor, so I don't think would have added to the CEL, don't know.

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