Some have said you need to weld a bung on it, some say drill a 1/4" hole and then stick a 1/4" NPT fitting in there and then the probe in there.

Now if I do the 1/4" hole with fitting, how do I get the fitting on there if there are no threads on the hole I just drilled? Do I have to tap it for threads? If so I guess I got to get a thread tap for that.

Seems like a pain and about "this" close to just drilling the hole into the Ypipe right below the flange from the header and just stick the probe there with the hose clamp. But alot of people are trying to sway me from that so I can get a better reading from the header.

If I do the header which bank?

Convice me which way to go. Im doing this this weekend to figure out why im having issues at 8psi wheather im running too rich or lean along with my fuel pressure gauge being installed.

Dixit

 

as far a I can remember thats the way that Autometer suggests with their EGT gauge...6 inches downflow from the header flange on the downpipe. Thats what me and my friend did on his Civic. Drilled a hole, popped in the probe, used the supplied pipe clamp and the small special sealant gasket ring between where the probe and the pipe meet(to seal it all up) readings were fine and it never had any adverse affects!

 

6" would be perfect, the just sit it right below the flange, only issue is that i have to drop the entire pipe first. Cause cant have metal filings falling into the pipe and then through the turbo. That is the biggest pain for a small hole.

Dixit

 

I always weld a bung on. If you drill and tap the SS its pretty thin so your taking a chance it will not hold. I do not like the clamp deal because when you get rid of your car or want to take the EGT off you have to deal with the hole. If you put a bung on you just thread in a pipe plug and thats it.

I also do the front pipe, easier to get to.

 

Understood on that selling issue, but the car is turbo, if i sell the kit it would be part of it since they would need the downpipe and all.

So in that sense it really doesnt matter on the hoseclamps to me, just how accurate it is or how much it is not.

Dixit

 

Dixit, check your sizes first. With my Apexi EGT, the probe is a 1/8 BSP fitting (Japanese pressure fitting). You wouldn't want to make the hole too large.

I'm putting mine on the pipe for the rear bank (closest to passenger compartment) right below the flange. I'm having a bung welded on and then drilling and tapping that because the pipe is too thin for my comfort.

Mardigras put his in the front manifold. I asked him about it and he suggested it's somewhat irrelevant as long as you're going to tune it on a dyno with wideband O2. Get your ratio set right on the dyno and then check your EGT temp, that's the number you want to work with. With various locations the temperature reading will be different so it appears that it's relative to each car's EGT probe location.

 

on a turbo car, the most accurate is going to be cylinder 6 i believe, it is the hottest.. I know this varies from the #5 cylinder many w/ nos etc will say. so, if you are to tap a cylinder, go #6 on FI cars... if you are going to tap a downpipe though, i've been told by someone who has tried both, the rear one is hotter, so use it..

 

Hal, that's interesting. On the 4th gen at least, cyls 1-3-5 are on the rear bank and 2-4-6 are on the front (based on Hayne's manual, a call to my dealer, and the position of closest cylinder from the front (passenger side) of the engine. Anyhow, I wondered about the same issue when making my decision. People say it's always cyl 5 that is a problem and then recommend tapping EGT on the front bank (nearest the radiator), which has 2-4-6. The last cylinder to get fuel, is in fact cyl 5, nearest the stock FPR and on the back bank of cylinders as you look at the engine from the front bumper. Or did I miss something here when I traced the line from the fuel filter?

Shouldn't 6-4-2, being first on the rail, get the most fuel from the fuel rail and therefor be richest and least likely to run lean?

Oh well, I'm set on where I'm tapping and I'll dyno-tune accordingly.