If you're using a coolant reroute, you cannot use a NB head gasket. The coolant reroute is specifically designed to fix the problem with the NA head gasket. The NB head gasked is also specifically designed to fix the problem with the NA head gasket. If you use both the NB head gasket AND a reroute, the NB head gasket solves the original problem, and THEN the reroute RECREATES the problem that the NB gasket solved...

I thought 94-2000 was the same HG, and it changed for 01+?

Where is that darn thread with all of the different HGs pictured?

Coolant reroute issues are only for the 01+ head gasket.

not completely, but most of the air does go through the intercooler

does this sound right or wrong....

sealed the area between the intercooler and the radiator with corrugated plastic sheet

sealed the sides around the radiator

skinned the bottom of the bumper back to the stock under pan mounting point on the subframe.

built a big duct, to extend the open area around the large bumper intake to the intercooler and the non covered area on the exposed radiator and oil cooler( mounted on the frame rail and ducted to the front. )
think I should remove this part?

yeah this was my understanding as well.

yeah, well my logic was that if I could get the thermo open sooner perhaps I would avoid saturating the system with heat to the point the radiator is unable to shed the heat but if this is the case, I have flow issue, possibly caused by a faulty thermo that does not open all the way which is why I was going to change it and go for a lower temp unit while im at it.. if that makes sense.


no under tray is made by me, one between the rad and intercooler and second between the bottom of the bumper and the subframe

no risers
no radiator cowel
AC deleted

Logic is flawed. Radiators transfer heat by conduction. With conduction, the rate of heat transfer is proportional to the difference in temperature between the coolant and the air. To increase the heat transfer rate, it is actually desirable to increase the temperature of the coolant -- all other variables held constant. That's why you often see a hotter thermostat as part of trailer towing packages.

Personally, I'm not a fan of remote mounted thermostats like you find in the M-tuned kit. It can cause control issues. That's why the stock thermostat housing has that little bleed line to the mixing manifold at the water pump inlet. Not saying that's your issue, just something to consider. My reroute uses the BEGI spacer that puts the thermostat directly at the back of the head. It works really well (as per the original design intent on B6 and BP engines).

BTW, you could try running without a thermostat. Might indicate whether you have a flow/blockage problem somewhere else.

Take a picture of this.

There's one more thing with the M-tuned that I almost forgot. With the M-tuned, the coolant bleed that allows the T-stat to see true engine coolant temperature is accomplished with a drilled hole in the T-stat base. If this hole is not present (because you changed the T-stat and didn't realize how critical it was) or if the hole gets clogged, you can expect a significant delay in T-stat reaction to coolant temp. It is certainly worth a look.

you make some good points. very interesting about the temp differential and affect on cooling. when I bought the m-tuned I did not think about it enough. wish I had got the BEGI better and cheaper.

In regard to what Sav was asking, if the only air getting to the radiator has to come through the intercooler first, you aren't likely getting enough air to the radiator. Likewise, if all air entering the bumper mouth is forced to pass through the IC, you are blocking airflow.

I've had this kind of problem at the track. I moved/angled the intercooler to allow more air to get around it and to the radiator.

While true, it doesn't sound like his issues are coming from a late-opening thermostat. As you mentioned previously, the transfer rate is proportional to the difference in temp. So if he had a late-opening thermostat (and no other problems) I would think he might get spikes to 235, but then it would eventually level out.

I also am interested by what he means by 'plastic between the IC and rad'. I hope he means "sealed the sides of the IC to the rad".

I can envision a scenario where, if there is excess cooling capacity (and, this time of year, there should be), one could get into a cycle where the thermostat has a series of late-openings followed by rapid closings. This could create this kind of temperature offset on a continuous basis (the temp gauge would smooth out the spikes).

Just a theory, mind you. Threw out the stat bleed hole as something to check. I think with the M-tuned, checking the stat is pretty easy. That's one definite advantage of the M-tuned.

so the bolt holes on the bottom of intercooler, and the small tabs on the bottom of the radiator were used to attach a piece of plastic in a fashion similar to that of stock under tray. I will get a pictures today

Like this?

https://www.miataturbo.net/attachmen...ine=1367605846

Because that might explain your problem. If everything is ducted to the IC and THEN to the rad, you aren't getting enough cool air to the rad.

alright, very good thank you! i will go take some pictures of what I have.

I think I might have a better solution, I will take the piece between the ic and the radiator and drop the front on the intercooler with a spacer or something so that it will scoop air from under the IC.

yes that is what I did, your picture is correct.

So i need to rethink how I did this.

https://www.miataturbo.net/race-prep...g-ideas-69274/
the first image looks like mine.
it will be cold this weekend so it will not be an issue. only on hot humid days does the car run really hot. not as hot as the turbo viper guy but pretty hot none the less.


perhaps someone has a link to sealing the radiator properly?

my plan is to remove the attachment and see if I can drop it to the undertray skin attached to the bumper, or seal the undertray to the rad directly