177 replies to this topic

[Bench Racer]

 

I think a case can be made that all of the cars experience heat soak on the track which to me makes them "equal" in that regard. 

 

Isn't this an updated example of the engineering over all other considerations approach that produces rules creep?

 Not really. All Miata's from 1990 - 2005 have an issue when racing with the rear cylinder heating up shall we say beyond normal with negative impact on the engine/acceleration/lap times.  Mazda after the fact provided a somewhat solution for the NB cars with a different than normal OEM head gasket (restricts water flow to the forward cylinders, therefore more water flows to the latter cylinders)  (don't know the exact release date of the different than normal OEM head gasket) partially solving the current cooling water route for NB engines. Rerouting the water to it's Mazda 323/232GTX original route would be a better solution than a water restrictive gasket. < That's what my previous post is about. Second choice would be a water restrictive head gasket for the NA cars which Mazda did not offer. I haven't checked on an aftermarket head gasket, but as you well know there available. That'll be something for next week, gasket cost estimate from Cometic Gasket after reviewing the NB gaskets. There's a reason several aftermarket companies offer a water reroute system for somewhere north of $300.00. Stated again, my water reroute is completed with all Mazda OEM parts existing on the 1.6 engine except the hoses. YES, I understand your "engineering over all other" comment, BUT Mazda didn't play equal of the NA engine to the NB engine. This whole reroute deal will stop the engine from laying down latter laps in a race.  

 

It's always talked about folks being mentors on this site and it's quite amazing how folks loose their ability to type and or talk. And again some of those same folks comment on how cheap the 1.6er's are.     

 

[chris haldeman]

I'll add just this to the cylinder 4 running hotter issue. Head gaskets are open per the rules and there are more water passages in both the head and the block than there are in the stock gasket. Take that for what's it's worth.

[Rob Burgoon]

Isn't this an updated example of the engineering over all other considerations approach that produces rules creep?

 

Sounds like you like showroom stock.  Those classes have seen better days.

[Rob Burgoon]

WTF is an air intake sensor kit??? 

 

temp.

 

A pyrometer duct taped to my windshield with a gopro pointed at it probably would work.

[Bench Racer]

I'll add just this to the cylinder 4 running hotter issue. Head gaskets are open per the rules and there are more water passages in both the head and the block than there are in the stock gasket. Take that for what's it's worth.

Thanks for response, Your speaking of 2001-2005 for sure and maybe 2099-2000 because there is one hole less than the 1990, I've never had these in hand. 1990-1997 all holes block, head, gasket equal. Understand gaskets are open per rule.

 

temp.

 

A pyrometer duct taped to my windshield with a gopro pointed at it probably would work.

 

Your more anal than me. I pulled the under hood thermocouple out of engine bay to ambient air while car was static.

[Peter Olivola]

Not particularly.  I do like classes where decisions have to be made on what car to select and what can be done with it based on a stable set of rules.  Classes that don't have also seen better days.

 

Sounds like you like showroom stock.  Those classes have seen better days.

[Rob Burgoon]

 

 

 

I pulled the under hood thermocouple out of engine bay to ambient air while car was static.

 

Do NA 1.8s have that?

[Bench Racer]

Do NA 1.8s have that?

The under hood thermocouple is attached to a $30.00 multi meter which is installed on dash to check temp's anywhere under hood. The thermocouple type K was only 30 inches long so I sourced a 10 foot thermocouple for $10.00 on the internet. So yes, your NA 1.8 could have the same.

[chris haldeman]

Thanks for response, Your speaking of 2001-2005 for sure and maybe 2099-2000 because there is one hole less than the 1990, I've never had these in hand. 1990-1997 all holes block, head, gasket equal. Understand gaskets are open per rule.


Your more anal than me. I pulled the under hood thermocouple out of engine bay to ambient air while car was static.

Bench, you need to take another look at the water jackets in head and block compared to holes in head gasket. All Miata motors have water jackets blocked off by the head gasket. Factory Mazda gasket has 1 additional hole opened up on cyl4 but the holes are very small compared to jacket. Maybe a simple drill thru the gasket would be a good idea

[chris haldeman]

Bench, you need to take another look at the water jackets in head and block compared to holes in head gasket. All Miata motors have water jackets blocked off by the head gasket. Factory Mazda 1.6 gasket has 1 additional hole opened up on cyl4 but the holes are very small compared to jacket. Maybe a simple drill thru the gasket would be a good idea

[Bench Racer]

Not particularly.  I do like classes where decisions have to be made on what car to select and what can be done with it based on a stable set of rules.  Classes that don't have also seen better days.

A stable set of rules is nice as long as when another spec line is added the SMAC/CRB keeps the previous spec lines in tune with the new spec lines. In case of NB's being added after the NA's keeping the spec line in tune was not adhered to. It took forever to get a bone thrown to the 1.6 NA last year to improve power. Next item on the list is engine laying down late in a race. Real known issue water flow thru block and head more commonly know as heat soak. This block/cylinder head water flow is an issue for all NA and NB cars except not so much the 2001-2005 where Mazda implemented a gasket which restrict flow of water for the front two cylinders. If my minimal search is correct the blocks for the 1999 through 2005 are interchangeable meaning the 2001-2005 head gasket could be used for any 1999 through 2005 engine. Straight up from Mazda there is no water restrictive head gasket for the 1990-1993 1.6 engine. Yes head gaskets are open, BUT at what cost to an individual as compared to if Mazda offered them for the 1990-1993 NA 1.6 as they do for the 2001 through 2005. A more cost effective water flow process for the 1990 through 1993 would be as per my previous post using all OEM parts except for hoses and re locating the thermo sensor. Yes the gasket for the NA 1.6 could be massaged and I will get a quote for a restrictive head gasket.

[chris haldeman]

This is the balancing act. Is a restricted flow to cyl1 the answer or is an increased flow around cyl4 better? Just compared a Mazda 99 gasket and a Mazda 01-05 gasket. All passages are the same size only change is on cyl 4 there is a swap as to what passage is open and which is closed.

[Peter Olivola]

Why aren't you investigating Chris Haldeman's suggestions?

 

A stable set of rules is nice as long as when another spec line is added the SMAC/CRB keeps the previous spec lines in tune with the new spec lines. In case of NB's being added after the NA's keeping the spec line in tune was not adhered to. It took forever to get a bone thrown to the 1.6 NA last year to improve power. Next item on the list is engine laying down late in a race. Real known issue water flow thru block and head more commonly know as heat soak. This block/cylinder head water flow is an issue for all NA and NB cars except not so much the 2001-2005 where Mazda implemented a gasket which restrict flow of water for the front two cylinders. If my minimal search is correct the blocks for the 1999 through 2005 are interchangeable meaning the 2001-2005 head gasket could be used for any 1999 through 2005 engine. Straight up from Mazda there is no water restrictive head gasket for the 1990-1993 1.6 engine. Yes head gaskets are open, BUT at what cost to an individual as compared to if Mazda offered them for the 1990-1993 NA 1.6 as they do for the 2001 through 2005. A more cost effective water flow process for the 1990 through 1993 would be as per my previous post using all OEM parts except for hoses and re locating the thermo sensor. Yes the gasket for the NA 1.6 could be massaged and I will get a quote for a restrictive head gasket.

[Bench Racer]

Why aren't you investigating Chris Haldeman's suggestions?

 

If your referencing using the 1999-2005 head gasket, they don't fit on a 1.6 engine. Next week I'm going to get a quote for a restrictive 1.6 head gasket. BUT, I could screw up a time or two in providing info to the gasket manufacture to get the gasket correct, can you say $$$$$$.

 

Without a having a quote for a 1.6 restrictive head gasket, there's no question my reroute using Mazda OME parts is more cots effective. And then the water route system would be as intended from day one. which would be pre Miata days.

[chris haldeman]

There is no restricted flow on any 1.8 gasket. There is simply 1 different hole location. On the 1.6 simply open up the 2 very small holes thru gasket on cyl 4 to increase its water flow. I've been doing it forever

[Bench Racer]

There is no restricted flow on any 1.8 gasket. There is simply 1 different hole location. On the 1.6 simply open up the 2 very small holes thru gasket on cyl 4 to increase its water flow. I've been doing it forever

I very much appreciate your knowledge/input. The following is where I'm obtaining my info other than the 1.6 gasket in hand. Viewing the 2001 head gasket there are missing gasket holes for cylinders #1, #2, #3 and rearranged holes for #4. I do understand opening the two small holes at cylinder #4. Trust me, I'm not being disrespectful. I'm now going off to the Mazda Motor Sports site to view their gaskets if the have pictures. Haven't been there in a while. EDIT: Went to Mazda Motor Sports site and head gasket pictures are not worth looking at.............

 

1993  Head gasket http://www.enginepar...CFQhWDQodf1sNCQ

 

1994 Head gasket http://www.enginepar...CFUxLDQodoWELjw

 

1999 Head gasket  http://www.enginepar...CFYRKXgodaA8Djw

 

2001 Head gasket http://www.enginepar...CFdgSgQodzP8KZw

[chris haldeman]

I am not feeling disrespected. I'm just trying to shorten your journey down a long winding path

[Johnny D]

From the 949 reroute...

Basically it says what has already been said but check out the bottom...

But not much help for the NA though unless you do it yourself.

 

http://949racing.com...ute-system.aspx

 

Why the Miata has a built in problem
The Miata's engine was designed for a front wheel drive car then turned 90* lengthwise in the Miata. To make it fit, Mazda's engineers moved the coolant outlet from the rear of the head where it belongs, to the front of the head. As a result of this backwards flow, only a small portion of the total coolant water flow goes around the 4th cylinder at the rear of the head so it runs hotter that the front of the engine. In addition, not all of the heat the engine generates is being fed to the radiator so a much larger radiator must be used even for mildly tuned engines. Even a bone stock first gen Miata will kick on its cooling fans in steady state hot weather highway cruising with the A/C. As soon as you hit the track or add power the OEM routing becomes a major problem no matter how big the radiator or how much venting/ducting you have.

 

The reroute returns the coolant flow path to the correct configuration used before the Miata came along. In addition, the kit retains full functioning of the original system including correct sensor locations for the stock ECU, heater, bypass circuit operation for proper warm-up and cold over-pressure protection.

 

01-05 owners: Mazda changed the head gasket design for these years to restrict flow to the #1 cylinder to help alleviate the cooling issues. The 01-05 OEM gasket works fine with the reroute but will work even better with the BP26-10-271 gasket from the 94-00 engine. So if you are rebuilding your 01-05 VVT engine, consider the 94-00 head gasket.

[Johnny D]

On another note...

 

Were getting a rewrite of the qual to the runoffs in this edition ?

 

J~

[Johnny D]

So before the "949" reroute...

 

1) If your getting heat soak your already running with your heater on or it's not as bad when you do ?

 

2) Sounds like Chris opened up the gaskets. (Still heat soak ?)

 

3) Can someone test a reroute of the heater hose out to a "T" at the Rad inlet ?

 

These would use the smaller OEM hose but it would run out the back of the engine and cool #4.

J~