Coolant mods - higher compression setups

[jason_]

Alright

Finally got my disaster together. Thank the previous engine for putting a flame under my ass. She burned another valve the other day. And it's my daily driver.

1.3, factory ecm,
Polished the stock head.
Milled 0.048" off head
Clevite pistons. Jumped from factory 5cc to 3cc
And she's 0.02" over.

Had to jump a tooth on the cam gear, factory line up would spit past intake valves... So, quick fix was to clock cam one tooth. Not sure if it was too much, or not enough, regardless if either, will need an adjustable gear. Anyways, it runs. And damn good too, even if it's not perfect. I'll vacuum gauge it later this week.

It's odb1, so I can't realtime scan with my scanner to grab temp readings. I'm breaking it in without the thermostat.

Had a partial tank of 87, and topped with 92. When temp gauge starts to creep into mid warm, with factory 10* advanced she starts to chatter at lower rpm, ie gagging engine with clutch to roll ahead. Given, lugging higher CR engines it'll happen, but hotter it gets, worse it gets, and it's a lot when radiator needs fan assistance. Also would like to look into changing when the fan kicks on. Like to see the fan keep the radiator around 150/160.

I was going to experiment with a lower temp thermostat first. Question is, I have no time or knowledge hunting odd parts for this scenario, and wondering if ppl could help out. Or sticky this thread for anyone wanting to follow, or exceed what I've done/doing. I'll help out with what I've ran into, and what was needed to get around. But need to make sure the fan stays within reason with the thermostat, especially when sitting in parking lot, or heavy stop/go traffic.

If I can get this under control, and stay on pump gas, wondering if I could of gone further? Mhahah, 2 more heads sitting under bench...

I guess I'll just post this and see what questions arrive?

Thanks ahead of time.





Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[Aaronbrook37]

I have no idea whether they fit, but Mishimoto makes B6/BP Miata racing thermostats. I've seen a 140 and a 155 on Ebay as of late. Check if they're the same part number at your local Mazda dealership or try playing around in the junkyard a little bit.

[XFSE71]

Your thermostat is designed to bring your engine up to minimum temperature as quickly as possible. The minimum temp is about 192º. Have you ever heard a cold engine knock upon start up? That's the sound of the pistons rocking in the cylinder bore, when they are cold they are too small for the bore. This causes wear to the piston and rings. When the piston rocks the rings pull away from the cylinder wall and dump combustion gasses past into the oil. The rod and main bearing are also loose until running temperature is achieved, less boundry lubrication and contact with the crank journal and the bearing causing rapid wear. There is moisture in your engine oil from shutting down after the last drive. Similar to a glass of ice tea on a hot muggy day draws moisture from the air. That moisture reacts with oil to create acids that will break down the oil, etch your bearings and destroy your engine. Moisture has to be boiled off to prevent an acid reaction and sludge formation in the oil. Sure oil additives can compensate for neutralizing some of that acid but, the additives will be depleted in short time. By design the moisture is removed by reaching boiling temp in the oil.

The fan is designed to remove excess heat, and prevent the pistons rings from butting (ring end gap) and the pistons from expanding too much which causes scoring and galling of the piston and of the exhaust valve stems. Have you ever been inside an overheated engine? Pistons will get so big that you can see where they scrubbed on the cylinder wall, as a result they collapse.

The way to keep the engine temps healthy is to run in that 200º - 275º temp range. A good thermostat in the proper temp range, a sealed cooling system 13# cap and 50% antifreeze will raise the boiling point in your cooling system to 260º. That is enough boil off any moisture, expand your pistons and rings to the proper size and promote complete combustion. Do not drop to a cooler thermostat, it is not a good idea ... just saying.

[jason_]

I'm going for it. It's just an engine. Nothing serious. By the sounds of it i shouldn't be running 15w40 diesel oil year around either? Hm. Bottom end is still good just burned a valve. Replaced the valve, and she's now an awesome wood splitter power plant. By the sounds of it I'm sure you'd cringe knowing I filter all my drain oil through a milk filter, and use it in the hydraulics of all my heavy equipment.
The 56 ford tractor vickers vane still pumps like a champ.....

Our T750 with a 332 hd to this is day runs strong and quiet, still pulls 80,000# daily. Hasn't had a thermostat, and still doesn't, for its 17 years of duty, and has a radiator 2 men dare handle empty.... My point is, never had an engine fail because of cooler temps, no matter what it is. Ford, Chevy, Mazda, dodge, engine is an engine.

I guess I have a different prospective of things, since I have 6 b3 blocks, 12 small block Chevy, a handful of ford's just laying around. All kinds of goodies to experiment with. Even a real big block monster, the 534 cuber from a F850...

Sooo, anyways, off topic, the goal continues...

Thermostat mods? I've saw 150s and 180s for Chevy mods and such. Any idea for the b3? I could weld up something to fit a Chevy thermostat. Modify the b3 housing?

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[sketchman]

A 332 hd isn't a Festiva.

Check Rockauto.com. They have different Tstats that fit the B3. Several different temps to pick from.

[jason_]

A 332 hd isn't a Festiva.

Check Rockauto.com. They have different Tstats that fit the B3. Several different temps to pick from.

Festiva and 332

Both burn fuel, have oil, and use thermostats.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[jason_]

Any leads where to modify radiator fan relay to engage at a lower temp? Or is that flashed into the ecm?

My 150* stat will stay open because the fan turns on when it's even hotter.

If I can't change it, I'll just hot wire it with another replay and ignition,


Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[sketchman]

Both burn fuel, have oil, and use thermostats.

It's your engine, and it's your time, but that argument makes no sense.

Anyway, options are available at RA.

[jason_]

I have no idea whether they fit, but Mishimoto makes B6/BP Miata racing thermostats. I've seen a 140 and a 155 on Ebay as of late. Check if they're the same part number at your local Mazda dealership or try playing around in the junkyard a little bit.

Hm perfect.

Some rainy day bore something on the lathe to fit a tstat, and bolt pattern , then tig weld a snout on it, worse case scenario.

Next step is changing temp range for electric fan, if possible

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[Aaronbrook37]

On my white B6T car, I have a slim fan wired in using an adjustable fan switch. http://www.summitracing.com/search/d...an-control-kit

[sketchman]

Unless you just want some super low Tstat, rockauto shows a 160 MADE FOR THE B3. Bolts in. No mods needed.

Oh, and for that matter, why not just gut a stocker if it's a cold engine you're after?

[Rocketman]

Festiva and 332

Both burn fuel, have oil, and use thermostats.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

Both have very, very different tolerances and clearances...you can get away with a lot more on one vs. the other.

Most parts stores should be able to order a 160-180 degree thermostat for you same day/next day. It shouldnt be hard to find one at all.

XFSE71 nailed it though, I wouldn't really recommend running too cold and certainly not running a tstat at all. Maybe look into a larger radiator where you can quickly shed more heat

[jason_]

On my white B6T car, I have a slim fan wired in using an adjustable fan switch. http://www.summitracing.com/search/d...an-control-kit

Beautiful. No thermostat isn't an issue, unless it's below 30F. It's making somewhat heat when doing 60mph, but it's because it's warm out. Last winter the 192 hung open. Burning heat when parked, 1 mile down the road cold air...

This adjustable kit with sketches 160 suggestion, I'll give this a whirl next month. , see how this turns out.

Unless you just want some super low Tstat, rockauto shows a 160 MADE FOR THE B3. Bolts in. No mods needed.

Oh, and for that matter, why not just gut a stocker if it's a cold engine you're after?

I don't get the stocker?


Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[mattdickmeyer]

Burnt valve caused by lean / high combustion temp , the pre ignition you have adress that, your chasing your tail with t stats and radiators. Start with correct cam timing , too much advance or retard can cause this.

[jason_]

Burnt valve caused by lean / high combustion temp , the pre ignition you have adress that, your chasing your tail with t stats and radiators. Start with correct cam timing , too much advance or retard can cause this.

Last engine didn't have pre ignition. It had 460,000 miles. And it was factory cam timing.

This 2nd setup is a crazy mad scientist project.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro