inlet temp?

[Grizzly]

Hi all.

I\'ve been playing with the Fd in an attempt to keep the inlet temps down, today i noticed that after a good run down the motorway the Ic pipes where stone cold but the Throttle body/Upper inlet and Lower inlet where quite hot.

So after a bit of thinking i\'ve decided to make a shield that goes between the Engine and Inlet to stop any heat rising from the engine but when i first felt the heat of the manifold i put my hand under the inlet and tbh it didn\'t seem that hot under there?

I have been looking to see how i could make the Shield and noticed there is two coolant pipes going to the Throttles (i\'m guessing there for the cold start??) do you think there is enough Transferred heat of the Coolant to heat the Upper manifold given that it was after an hour or so of cruising at motorway speeds??

I don\'t quite get how the elbow of the inlet can feel cold while the throttle its bolted to has got to be 70deg or so??

BTW i don\'t know if it makes a difference but the FD has been modded to run a Single and so quite a bit of the Rats nest is missing.

[SmbFD3S]

The throttle body will always be at the same temperature as the coolant being as there is a bypass to this from the system for, as you say cold start. It\'s basically to stop the freezing of the fuel vapour in cold weather so i\'m told.
 
Problem you have is that everything connected is metal and a good conductor of heat, so will heat soak to an extent.  I asked the question about whether it would make much of a difference removing the TB coolant lines but i was told no, so left them there.
 
Should be easy on yours without or the crap underneath the UIM to get a heat mat made up or something to stop rising heat....

[jackaleks]

Rob Robinette\'s site has a good guide on removing the throttle body\'s coolant lines (apparently they stop ice forming inside). There probably isn\'t any benefit other than simplification and tidyness!

[Grizzly]

So does that mean the air temp sensor is picking up heat from the manifold as well as the air? Because i\'m seeing readings of 70 odd degree\'s, when the intercooler to throttle pipe doesn\'t feel half that?

Out of interest after a run does your Upper Inlet get hot (50-60deg) or does the Throttle body get warm and the Upper inlet stays cool?  I\'m just thinking that maybe its the Heat off the Turbo/Exhaust heating the Inlet manifold from the other end?

[memski]

Removed mine, not a problem since really. I ran the same coolant line from the rear plate to the waterpump.

[Laeeq]

I have 2 temps sensors on mine:Tongue1 one in the elbow for summer times and one in stock position for winter/ cold days... just extend the wire long enough to switch over.

[SmbFD3S]

Have you got the standard (OEM) air inlet temp sensor or the new RIAT sensor?
 
The OEM temp sensor heat soaks, so yes you\'ll see temps of that but  the air will actually be cooler than that, it\'s just the sensor is not quick enough to pick it up...
 
The upper in manifold is bound to get hot as it\'s metal (conduction) and surrounded by hot things while the throttle body will be hot as there is coolant flowing through it.

[Grizzly]

Interesting, Does it Idle much differently when you start it from cold? (with the Coolant lines off)

I have been reading up about removing these Coolant pipes and from what i read as long as you wire the Cold start assembly half open it will start and run exactly the same?

I still have the std air temp sensor, Where do i get hold of the newer one? and is it a direct swap?

[Grizzly]

I have 2 temps sensors on mine:Tongue1 one in the elbow for summer times and one in stock position for winter/ cold days... just extend the wire long enough to switch over.

Sounds good, i wouldn\'t mind putting one in the lower manifold to see how much the air temp is raised by the manifolds being hot.

[Grizzly]

I am presuming this is the new sensor http://cgi.ebay.co.uk/Mazda-RX7-Racing-Inlet-Air-Temperature-RIAT-Sensor_W0QQitemZ250419437941QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item250419437941&_trksid=p3286.c0.m14&_trkparms=72%3A1683|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A1|294%3A50

[SmbFD3S]

Yes thats the new sensor, it is a direct replacement yes you just need to cut the connector off the standard one and solder it to the new sensor wires (irrelvant which way round they go) and then plug it back in, and put the UIM back on...

[memski]

Why not leave it in the elbow all year round laeeq?

No problems with idle once mapped and setup Grizzly, removed most of the gubbins from the tb too.

[Laeeq]

Why not leave it in the elbow all year round laeeq?

well in tooo much cold inlet temps the car will drink more petrol so to keep the inlet temps at reasonable level just keep switching over only takes few seconds:Giggle

[Grizzly]

Right, i am drawing up a shopping list at the moment hence the daft questions

Has any of you had any experiance with those Thermal gasket things??

http://cgi.ebay.com/ebaymotors/GIZZMO-INTAKE-THERMAL-GASKET-93-96-MAZDA-RX-7-13B-FD_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1683Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a0Q7c293Q3a2Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem150095400092QQitemZ150095400092QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
http://cgi.ebay.com/ebaymotors/93-95-Mazda-Rx7-Intake-Gasket-Set-FD3S-13b-TT-NEW-NEW_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1683Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem350191049869QQitemZ350191049869QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

I\'m also looking at ordering a RIAT sensor.

I have just bought a load of nimbus G3 to make some heat shields from, after ten minutes of my car running i can\'t touch the lower inlet as its way too hot i think its from Radiated heat from the Turbo but it could also be transmitted from the engine.

All in the quest for low inlet temps..... Now its been pointed out i have noticed how the heat travels up the lower inlet, i stared the car from cold yesterday and stood there for a few minutes feeling how warm the inlet was, its amazing how you can Track the heat rising up the manifold, also its Amazing hot hot it gets in such a short space of time.

Would love to stop all that.