Exhaust Temperatures. Is anyone recording ?

[C J R]

I do not have an exhaust temperature gauge fitted, however I wondered if anyone else does and could advise typical temps.
 
I am running a Garret GT40 on a HKS manifold and 3" down pipe with a 450bhp map at the moment.
 
I understand the data may not be exact but its just to provide an indication.
 
Thanks

[turbotoaster]

depends where the egt sensor is fitted as that affects the temp you will be seeing., pre turbo or post turbo for example

are you running one/two at the moment?

[C J R]

depends where the egt sensor is fitted as that affects the temp you will be seeing., pre turbo or post turbo for example
 
are you running one/two at the moment?

Pre turbo temp would help.
I\'m running a single GT40.

[turbotoaster]

if its celsius then 800-870 under full boost
if its fahrenheit then 1500-1600

[C J R]

if its celsius then 800-870 under full boost
if its fahrenheit then 1500-1600

Brilliant, thanks

[PGiljevic]

I am recording them between the engine and the turbo.

There are a few very important notes you need to know about Exhaust gas Temperature before you start taking the readings as gospel.

They are effected by:
*The turbine housing size ( a 1.00A/R will give higher EGT v\'s a 1.32A/R with identical tuning)
*The turbine wheel size (smaller turbine is higher EGT v\'s a larger unit as above)
*The level of power you are "flowing" (EGT goes up with power level and matching exhaust system pressure which holds in more heat)
*The types of sensors you are using (exposed or open)
*Where the sensors are located (how far into the stream of gas)
*How long they are exposed to the level of heat (5th gear at 200mph always yields far higher EGT than does a dyno pull or a 1/4 mile run)

Generally a turbo rotary will run *healthy* at ~1000deg C, if its set very heavy in fuel this can be dropped to around 950deg C, if its water injected and heavy in fuel this can be close to 900deg C.

T04S to T51R sized turbos running between 400bhp to 800bhp power levels are covered by the above.

This level of EGT I have proven to be fine over 10\'s of thousands of KM in multiple cars, turbine wheels tips intact, engines retain compression, no untoward signs of bad operation.

You can have lower EGT readings (see my site for examples under WI page) but these are usually data logged in transient conditions (say a 3rd gear pull on road) where the engine and turbine are only under load for a few seconds at a time.

Inconel 600 encased thermocouples are the only type that will survive in a rotary engine long term (these will yield lower readings in transient conditions) but sustained high load *top speed run* will give same readings as exposed junction versions. The exposed junction versions are and do become "fouled" with moderate use *3000km road running) and the wires are prone to failure *bending* due the massive exhaust pulse energy & flow in a rotary engine.

Some tips, hope I have not bored you.?

I\'ll post up some EGT readings from my own car in a couple of days along with a graph of matching Air Fuel Ratio, power level, Timing and other details if its of use to people in some more advanced detail.

[PGiljevic]

http://www.riceracing.com.au/vbox-iii-testing-tuning.htm

This is from a 600+rwhp (dynodynamics) 13B bridge port T51 turbo (very large rear housing and MASSIVE turbine wheel *much bigger than off shelf units*) car running 25~27psi, Shell Optimax petrol and water injection system, pull through 3rd gear on road. Enclosed type thermocouples.

http://www.riceracing.com.au/Photos/WI%20numbers.jpg < click her to see pic in full size

[C J R]

Wow Rice Racing, thats a lot of data and much appreciated.
 
Maybe I should explain why I am suddenly so interested in exhaust temps.
 
I recently purchased a turbo beanie (blanket) from a Rotary Outlet. It is rated to over 1000 degree C.
With the new blanket fitted I ran the RX down the Motorway for one junction (5 minutes) boosting to 0.9 bar (450 bhp), stopped at off ramp to see lots of smoke from vented bonnet, pulled in to layby, opened bonnet to find turbo blanket on fire !
 
The supplier is resolving this problem with me, so its not a name and shame thread.
But I am concerned that fitting a replacement will lead to another fire.
 
Hence questions.
 
As my set up has been fine for 3 years and has been mapped by a specialist I can assume it runs okay and not too lean etc.
So, I have to assume the turbo blanket was either faulty or not correct for my set up.
 
Thank you for supplying your data.

[PGiljevic]

^ I had a similar thing happen to me with some fire blanket material I used to insulate/protect some turbine outlet pipe are with, smoke and flames and the blanket was on fire! (same as you). I took the stuff of and made a heat shield instead

For my turbine housing I use a DEI woven blanket (quiet expensive but excellent quality product), before that I had a generic E-Bay item that worked well also (was just a bit fragile taking it on and off etc = ruined).

This is the exact one I use now > http://www.designengineering.com/category/catalog/component-specific-productst/t4-titanium-turbo-shield-kit

[C J R]

Yes I had heared that heat wrap and blankets with Titanium in were better for heat resistance.
 
Thanks

[leon]

A little OT. Would you say running an EGT post turbo is about as usfull as peeing onto a bomfire to try put it out? Or does it have some use as a rough gauge?

[Furb]

pre turbo is better, but post turbo isnt that bad either..
 
if you know what temps your car is running normally, you will notice if there is a definate change in temps.
 
i have mine post-turbo and usually run around 850C when pushing it.
had it up to 900+ on the track.
 
i alsways enjoy the temp spikes after letting off the throttle, my gauge shows if i am shooting 6-foot flames :p

[leon]

Mmmm I suppose your right. If everything else is a constant you will be able to see a "norm" from the gauge. Don\'t think i\'m going to use it to do any serious ignition timing tweaks with it being post turbo though.

[PGiljevic]

Another little tip, if you want to know your true EGT you need to do some back to back to back runs up to 140mph or so and 8000rpm in 4th gear, THEN you will know exactly how hot you are running.

New record for my little cat equipped road going RX7 100kmh to 200kmh of 7.53 seconds! *** Right click VIEW IMAGE to see the details***





http://www.youtube.com/watch?v=OqvaMTJZn8k

V\'s third gear pull below (lower EGT)

:conehead: Here is the graph showing some detail of various parameters & performance. Average figures between test lines shown (Avg-b) *report screen* and peak on datum line of graph in top left box snapshot of instant Graph data figures at that point.



If you can keep it under 1000deg C then you are doing well!

The Ti heat shield works perfectly, and will not catch on fire like your last one :flamed

[C J R]

Guess what\'s on my Christmas List....
 
Thanks for all your data..and have a Merry Christmas