Cylinder Head Temperature on a 2l aircooled

[WhatsTheCraic]

Hello everyone,

I've been trying to get an answer on this question for ages. So I specifically joined this forum to find out. Can anyone here tell me what the cylinder head temperature range should be on a type 4 engine.

My engine is a vw 2 litre, stock (CJ) aircooled engine. I am using a VDO CHT kit under spark plug number 3.

In deg Fahrenheit I am getting 340 idle, 365 gentle driving, 385 hills and fast driving. However the weathers very cold at the moment so I expect in the summer it would be hotter. Im concerned that this is hot so I would be gratefull if anyone could let me know what it should be at, and what too hot is?

Cheers

Dave

[Massive Type IV]

Sounds very acceptable if the sender is under the sparkplug. If its ANYWHERE ELSE its not accurate and probably reading low.

[WhatsTheCraic]

Thanks it is the spark plug sender, but can you tell me what the actual range should be or where too hot is? (For a 2 litre not a 1600cc)?

Cheers

Dave

[Sandeep]

Hi,

I've read that over 400 is hot at the sparkplug sender ... and this is what I use as a reference. Anything over 400 and you should slow down, or get a better cooling system.

I understand that AircooledTechnology is working on a much improved cooling system for a T1 ...

Sandeep

[WhatsTheCraic]

Thanks chaps,

If you have any related information/ or know where I can get the "official" info data please let me know.

[Massive Type IV]

325-365 is perfect, especially for a bus...

365-385 going up hills is acceptable

385-400 normal for a heavy load

400+ is hot.

[Dave_Darling]

There is no "official" info. :(

A few years ago, a buddy of mine wrote to Porsche asking about head temps in his 2.0 914 engine. They wrote back, "Ask VW--it's their engine."

So he wrote to VW. They responded, "We don't know--we never found it to be an issue."

I'm guessing that they simply tossed out all their aircooled data..... :mad:

--DD

[factman]

another thing about those CHT senders is it measures the temp at the plug in relationship to the ambient temp of the wire at the connector so it depends on how hot your engine compartment is or so ive been told by a reputable parts man that sells VW parts only. hes on here once in a while.

SAM

[Wally]

Originally posted by factman
.....the ambient temp of the wire at the connector ...
SAM

So, where is that 'reference' wire? Surely not in the engine compartment? Wouldn't the connection at the gauge be more of a logical place to work as a reference, since the inside of the car is held more at a 'room'-related temperature ?

Thanks,
Walter

[factman]

at the end of that short wire you attach to the #3 plug. so on my type 3 it will register lower than a bug with stanoffs since my ambient temp is higher in my engine compartment. double check with Jake and see if he knows how its works. that guy that told me is an electircal engineer so i would think he knows whats up though.

[njv]

hi
its a thermocouple and there is the hot end ie the ring that gos under your plug and the cold end is where the connector goes off with normal wires to the gauge itself.

now on a recent decent autobahn journy at 6oc i notice not for the first time my head temps reading about 35-50 f more than normal just recent outside ambiant temps have gone up to around 12 15oc and my cht reads what i consider normalof course with ambiant temps playing a part in the reading like this it tells me perhaps were getting a artificially low reading in the summer when its real hot outside!! this is possibly more cause for consern.

now your insrument learn where they normally sit on average any big deviations time to pull over is the way i look at it but typ4 i dont think you will be pulling over!

[factman]

thats what the CHT is meant for. the base readings should be close to what others have but it is meant as adeviation scale. if all of a sudden it goes up unexpectedly you should pull over but it will always read lower in the summer than in the winter unless you dont run a decklid on a bug or something. glad to see im giving good info out and not false info.

SAM