Exhaust Gas Temp

[Mik]

Armed with a couple of thermocouples, I am going to start logging the EGT on my GTR.

The problem is mounting the thermocouples. I know ideally, I should use 2 and mount one in each manifold between the exhaust port and the turbine (or even one per cylinder), but this isn't really an option. I don't feel like pulling the turbos off for no reason.

The other option would be in the dump pipes, just after the turbines (ala BNR34 vspec), but again, I don't really want to pull the turbos off to get the dumps out, and I'd rather not weld a pair of bosses on the HKS dumps.

So...I was thinking of mounting one thermocouple on each branch of the front pipes, as close to the flange as possible. That way, I'd end up with the thermocouples maybe 10 inches away from the turbines. Will this be close enough?

What sort of EGT's are something to be concerned about?

[RANDY]

Why don't you buy a consult cable and monitor the EGT's through some shareware software? The cat's should already have a sensor in them unless they were removed at some point.

[Dale FZ1]

The closer to the source, the better. If you've gone to the expense of picking up two pyrometer kits (and they're not cheap), get the bosses welded on to your dumps. You can always use a bung if/when you've had enough of monitoring exhaust temps.

Monitoring temps pre and post-turbine would be an interesting experiment, similar to measuring back-pressure and probably a useful indicator of turbine efficiency. I just don't know anyone who's done it.

I have one installed in the dump, parallel to the O2 sensor.

My RB25 typically runs 550-620 in open loop light load running, 630-660 in close loop cruise, and about 720 max with a good hard full power run (not just a quick blat through the gears).

[PlasticStan]

Why don't you buy a consult cable and monitor the EGT's through some shareware software? The cat's should already have a sensor in them unless they were removed at some point.

<{POST_SNAPBACK}>

Not quite, they have a switch in them so that when the cat reaches a certain temperature, a light is turned on. That is all.

[NewKleer]

yeh, unfortunately u only get a 4.98v reading permanetly thru EGT in consult, so appears as though it only changes when its past that cutoff point (or never!)

[RANDY]

Oh? I could swear that my consult software showed a temp in degrees? =-o

I must be wrong, but i'll double-check it tomorrow. =-]

[NewKleer]

moneys on you being wrong

theres only water temp, and for z32/rb26 i think theres a few more (intake air, fuel temps)