What did i learn at Hampton today

WideOpenThrottle · Post by **WideOpenThrottle** » Sat Jan 12, 2013 5:02 pm

Firstly car performed wonderfully....not scary but very drivable & only got a little bit warm around the midday heat.First time in my new turbo set-up,race seat & harness.[Damm it was a hot day...need to go in winter only me-thinks].
Ended up in battle with a black Honda S2000 most of the time..initially i was faster everywhere but as the other fellow grew in confidence we ended up about neck & neck....i was faster in the corners

but his acceleration on the straights was a little bit better than mine

Felt good to get past a mustang several times plus a few beamers.
I was running with my headlight cover off for better cooling and found that this has cured my motorway stumble at cruise/vacuum as i drove home with it off as well.
Obviously i need to get more cool air into the filter & engine bay by the looks of it.
Only two other mx5's today and both were doing well for standard cars.

WideOpenThrottle · Post by **WideOpenThrottle** » Tue Jan 15, 2013 5:58 pm

So...to combat some heating at track days i have re-located the oil cooler so it no longer sits between the IC & the radiator & started to plug my top vent...apparantly it may be sucking out air that should be drawing through the radiator.

The new oil cooler position means now i will need a different front under-tray.

Furai · Post by **Furai** » Tue Jan 15, 2013 9:07 pm

Does the Oil cooler have quite an effect for cooling?Im deciding on what to do first radiator or Oil cooler.

Keith Jones · Post by **Keith Jones** » Wed Jan 16, 2013 8:08 am

In a piston engine about half the energy lost in heat (not including the exhaust) goes into the oil. So cooling the oil can have a significant effect on the overall engine temperature. However, cooling the oil too much will decrease the power. The optimum oil temperature is in the 100C - 110C range.
Do you have a overheating problem Furai?

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Jan 16, 2013 8:09 am

The radiator is way more important for cooling and to maintain good airflow through them.
To do this effectively incoming air must not go around the core and you need to ensure there is negative pressure behind it in the engine bay.If the air is not escaping quick enough from the engine bay then you dont have enough low pressure...hence why front bonnet vents & head-ligth ducts are useful.

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Jan 16, 2013 8:17 am

Best cooling mods...will try & hunt down the original source for this sometime.

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Jan 16, 2013 8:37 am

Here it is...on page 4 & post # 64 by Emilio of 949 Racing!

http://www.miataturbo.net/race-prep-75/ ... 848/page4/

Keith Jones · Post by **Keith Jones** » Wed Jan 16, 2013 8:57 am

Interesting thread. Emilio advocates a full width undertray. I always ran this and thought that maybe it did help with both water and oil cooling as it channelled the air directly over the sump. I had my oil cooler blocked off even in the hottest weather and finally took it off.

Furai · Post by **Furai** » Wed Jan 16, 2013 9:20 am

Keith Jones wrote:In a piston engine about half the energy lost in heat (not including the exhaust) goes into the oil. So cooling the oil can have a significant effect on the overall engine temperature. However, cooling the oil too much will decrease the power. The optimum oil temperature is in the 100C - 110C range.
Do you have a overheating problem Furai?

I wouldn't say its a problem but something I want more control over, thing is Im drifting(I get the needle 3/4 up if I do a session over a minute).

Once finished a hot run I drive at about 40kmh to cool her down. Im thinking a larger radiator and better fans would be the best for me since its all slow speed stuff?

Example http://youtu.be/u9lBTb2YbJc

Keith Jones · Post by **Keith Jones** » Wed Jan 16, 2013 9:30 am

I was going to suggest the same. You don't have the high airspeed to take advantage of ducting.

Angreal · Post by **Angreal** » Wed Jan 16, 2013 9:33 am

Looking at the autocross guys, better radiator + big fans seems your best bet. I'll let you know how it goes

although still need the shroud...

Snapfrozen · Post by **Snapfrozen** » Wed Jan 16, 2013 9:34 am

Keith Jones wrote:Interesting thread. Emilio advocates a full width undertray. I always ran this and thought that maybe it did help with both water and oil cooling as it channelled the air directly over the sump. I had my oil cooler blocked off even in the hottest weather and finally took it off.

The important part with the undertray is to make sure there is enough venting through your bonnet or the engine bay. By adding the tray you change the pressure in the bay and stop it from being able to vent the air going in. You create a positive pressure zone so the air stops going in and goes around. As long as you duct, the engine bay remains a negative pressure zone.

Duct around the rad and oil cooler so air is forced through them and can exit through bonnet vents.

Kieran, make sure you don't over cool. Would be worse not being able to get up to temperature. Try a better quality factory size rad with 2 fans, you might need to switch them... Failing that I know mishimoto make a 3 core for the Miata.

Furai · Post by **Furai** » Wed Jan 16, 2013 9:52 am

Ewww Miata

Im happy having to much cooling as I can block off sections or thermostat the fans.

Snapfrozen · Post by **Snapfrozen** » Wed Jan 16, 2013 9:58 am

Matt's getting a 3 core mishi for his 13bt build and rotors run dam hot. Maybe look into it?

Make a flat undertray, cut vents into your hood and duct around your rad which should force air through it rather than around. Bigger rad, 2 fans. Winning

Furai · Post by **Furai** » Wed Jan 16, 2013 10:01 am

Snapfrozen wrote:Matt's getting a 3 core mishi for his 13bt build and rotors run dam hot. Maybe look into it?

Make a flat undertray, cut vents into your hood and duct around your rad which should force air through it rather than around. Bigger rad, 2 fans. Winning

Would rather not be chopping my bonnet up, just big fans and a good 3 core should do it.

Angreal · Post by **Angreal** » Wed Jan 16, 2013 10:23 am

Would a large radiator not push the shroud into the sway bars? I know that even with the Dual Core Koyo I'll have to trim the shroud a bit or get a thinner one

Snapfrozen · Post by **Snapfrozen** » Wed Jan 16, 2013 10:37 am

I guess you'd need to do the upgrade and see how it goes but engine bay pressures dramatically affect cooling

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Jan 16, 2013 12:03 pm

Keith Jones wrote:Interesting thread. Emilio advocates a full width undertray. I always ran this and thought that maybe it did help with both water and oil cooling as it channelled the air directly over the sump. I had my oil cooler blocked off even in the hottest weather and finally took it off.

so did you have sides to your tray as well?

Keith Jones · Post by **Keith Jones** » Wed Jan 16, 2013 3:30 pm

Nope, just a flat tray that extended back to the sump.See pic.
I didn't have the radiator/intercooler ducted either.
When I first built the car I went to great pains to make sure that everything was sealed off at the sides and all the air had to go through the intercooler and rad. When I rebuilt the front end after an accident at Puke I didn't reinstate the ducting. It didn't change the temperature of water, oil or air (in the inlet manifold) at all.

Snapfrozen · Post by **Snapfrozen** » Wed Jan 16, 2013 6:02 pm

Keith, I have to ask...

WHERE DID YOU GET THOSE DUCTS!! They seem to be a perfect fit and exactly what I've been looking for. Any chance you'd mind sharing your secret?

Keith Jones · Post by **Keith Jones** » Wed Jan 16, 2013 8:13 pm

Marley downpipe fittings (rectangle to 60mm round adaptor) and very careful use of a heat gun!!!

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Jan 16, 2013 8:18 pm

More from Emilio on behalf of mate & mx5 owner

http://www.miataforumz.com/engine-upgra ... ation-812/

WideOpenThrottle · Post by **WideOpenThrottle** » Thu Jan 17, 2013 5:21 pm

Progress pics of the last couple of days

Combination of aluminium sheet,expanding foam & spa cover

Snapfrozen · Post by **Snapfrozen** » Thu Jan 17, 2013 5:39 pm

How thick is your alloy?

WideOpenThrottle · Post by **WideOpenThrottle** » Thu Jan 17, 2013 6:36 pm

The sheet was 2400 x 1200 x 0.7mm & cost $68.00 from Ulrich.

Easily cut with tin snips & hand sandable to smooth out burrs & get good shape.Nice & light too!

Its too thin to span the length/width but i have fixed it to an angle plate to stop airflow below the radiator

What did i learn at Hampton today

What did i learn at Hampton today

Under-tray & sides...nearly there

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