Does anyone know what size of bung I need to get for the Greddy EGT and O2 sensors? I didn't get them because I purchased the gauges new. Also, I was planning on relocating the O2 sensor farther from the turbos and installing the EGT sensor just before the Catback. Is this right?

 

no mount the EGT in the down pipe behind the o2 sensor.

 

Yeah, that is what I was trying to say. Sorry, not too clear in my description. I was planning on relocating the O2 sensor about 12-15 inches from the turbos and then putting the EGT sensor like 3-5 inches back from the O2 sensor.

 

you want that egt sensor close as possible to the turbo to get a more accurate reading, if you go down the pipe 10inches you will loose several degrees in temp and have an inacurate reading.

-Chris

 

The rule of thumb for N/A EGT is locate it at 1/2 of the diameter (radius) away from the mounting flange. So, on a 3" DP it'd be 1-1/2" from the turbos. Some people actuall put the sensor up streem of the turbos, in the turbine housing or the exhaust manifold. I just don't like that idea, since if the sensor bails do to the high heat of the rotary, it'd chew up your turbine wheel and housings something fierce, I'd wager.

Frank

 

So, I could put the EGT into the stock O2 sensor location and then add a bung for the O2 sensor down farther? Is it better to have the O2 sensor 12 inches away from the turbos? Thanks.

 

hmm, i beleive they give the bung when you buy anew gauge, i had one at least.

 

used, sorry, I bought them used. I was busy when I was typing the thread. Sorry.

 

O2 bung is a standard size, I believe its 18mm x 1.5 pitch. I know Jeg's sells them. Should be installed between 10 and 2 o'clock postions on the pipe where temp doesn't exceed 850-C. Most put it on the DP right after the curve where the pipe goes horizontal in the 10 o'clock position, there's a good bit of room b/t the pipe and transmission here.

Greedy EGT uses 1/8 in. NPT. If you have a thick wall DP such as RP, just tap the pipe. If thin wall such as ATR, you need a 1/8" pipe thread bung welded on. Sorry I can't tell you a value for thickness.

I was told by Chris at RP to locate the EGT about 10 in. past the DP flange and back off if temps get to 830-C when wide open. My Forum research shows most people put it anywhere from 4-10 in. from the flange.

Jack

 

I don't have this DP, but is this what I should do?

 

You want the EGT as close to the exhaust ports as possible, even if it means putting it before the turbo. The only sensor I've seen anybody have problems with is the Apexi EGT sensor. Defi, Greddy, HKS etc...never heard of one breaking. I recently changed turbo's and moved my EGT appx 6 inches farther from the engine than before...now my EGT's read WAY SLOWER and lower...

 

So, I should do this setup? With the EGT in the stock O2 sensor location and a new bung for the O2 sensor farther down the pipe?

 

For the picture above:
Put the EGT about where the original O2 bung is located. The place you show EGT would be acceptable but will run higher temp than I referenced.

Manifold is the the ideal place for EGT before the turbo but I've never heard of anyone puting it in the OEM manifold. I'd expect major cracking around a tap on that manifold. If you go single in the future, then put it in the manifold.

Put the new O2 bung on the other side of the pipe, transmission side where there's more room. You're showing it in about the 1-2o'clock position which is acceptable but there's more room for install/removal at 10o'clock.

Jack

 

So, is it not too important to have the 02 closer to the source? I would think that it should be closer but that's just an assumption on my part. Any feedback?

Frank

 

Okay, sounds good. My dp, which I think is a HKS mild steel (got it used), has the O2 sensor bung right up next to the flange for the mount to the turbos; that is why I showed it being located there. I don't really care if I need to install two new bungs and plug the HKS O2 bung. I just want to make sure I have them in the correct place. Rather do it right the first time. So what I will probably do is plug the O2 bung, install a new bung for the EGT at the location on the picture above that has the bung already on the pipe, and then install a new O2 bung at the location shown above but on the other side of the pipe. Thanks a lot for the help.

 

You want it so that the sensor doesn't see temps above 850-C. Manufacturer claims it will shorten the sensor's life but some people have them close and don't complain about short sensor life.

Jack