N555

I have a 88 10 anniv. turbo and am installing downpipe. Would like to keep most everything else in place for emission testing purposes. Seems that o2 sensor will hit on part of the acv. What is the quickest way to fix this. Would like to be able to just unbolt downpipe/ midpipe and put cats back up for testing. Don't really want to rework o2 sensor location either.
I guess what I'm asking is what is the least I'm going to have to remove. I thought I only had to block the split air pipe? Any simple answers? Thanks

Cosmo Donk

Huh? Do you mean the O2 will hit the split air pipe? Because the ACV is on the side of the engine and it is not anywhere near the O2 sensor.

All you should have to do is pull the old cat and disconnect the SAP (Split Air Pipe) from the back of the engine. The the pipe should not be hitting the O2 sensor when you put on the DP.

N555

Ahhh, I do believe the o2 sensor attaches to the downpipe, downpipe connects to the turbo, turbo is under acv on passenger side.

Cosmo Donk

Yes but the turbo is under the ACV, not the DP Here is a pic of my old setup with a block off plate. The ACV should be right above the oil line for the turbo and the DP is to the left.

Forgot the pic.

N555

Yea, just took another look, it's probably not the acv, but it does it some diaphram thingy, not sure what it is. Should go snap a pic myself.Thanks

N555

Is it possibly the egr valve I'm seeing that hits the o2 sensor. The o2 sensor location on the downpipe is not quite the same as the precat

N555

Heres the pic, I hope.

Funklord

i got the thunderfab dp/mp and had no problems with the o2 sensor.

fastrotaries

so where exactly is it hitting, because i had no problems with it.

gsracer

I have the thunder fabrications dp/mp as well. The o2 sensor is fine, and I got them to weld a bung for my EGT probe right behind the stock o2 sensor. Fell free to IM me if you have any questions.

N555

Would like to show you, but can't figure out how to post the pic.

N555

Probably EGR VALVE. What do you do with that.

ZachSpazz

I helped my friend install a Thunder Fab DP/MP and we ran into the exact same problem with the installation. We were using a brand-new Bosch O2 sensor and we cut off the little white plastic shroud from the base of the wire and actually used a Dremel sander to grind part of that valve's (EGR?) housing in order to get the pipe on. It doesn't require much grinding to fit the pipe on, but I think it's pretty shitty that Thunder Fab couldn't weld the bung for the O2 sensor one inch lower.