Oxygen-Sensor TR7 FI-engine

[Roger27TBB]

Hi all,

i need a new Oxygen-Sensor, because the thread is damaged when i dismantled the old one for taking the exhaust manifold for ceramic-coating. The thread of the manifold was also damaged, but i still have a repair set with 5 short bushes and drilling tools for cutting the finethread M20x1,5.
The old Oxygen-Sensor is from Bosch with part-no. 0258 003 578. I can`t believe that this
is the right number, because when i looked for the use in which cars it is built in, the cars have less power than the TR7 (88 Bhp). The engine, especially the exhaust manifold became very hot in the past (over 320°C), so i couldn`touch the auto body. I never measurded the exhaust-gas emission, and the MOT didn´t measure it until yet. So i can`t say if it`s o.k.
Does anyone of you has another part-no. for the Bosch Oxygen-Sensor or another part in
his FI-car ?

Cheers Roger

[birminghamtr7]

I bought and fitted a new one about 2 years ago ill see if i can get a picture of part number

[FI Spyder]

Hi all,

I can`t believe that this is the right number, because when i looked for the use in which cars it is built in, the cars have less power than the TR7 (88 Bhp).

I've seen two hp figures for the TR7 FI, 86 hp and 89 hp so it fits right in there. For some reason when the TR8 went to FI increased its HP from 135hp to 150hp but the TR7 when it went to FI went from 95hp down to the high 80's. I figure it must have had something to do with the difficulty in trying to get the slant four into the stiffer emissions level require in California (and the following year, the continental US). No wonder they didn't even try to get the Sprint engine to meet the emissions.

[Roger27TBB]

Hi, thanks for the reply.
This weekend i`m going to ask the Bosch-Specialists. Every year the Bosch Company here in Southern Germany (country Baden-Württemberg) invites Oldtimerdrivers to a special Oldtimer-Rally. It is starting at the headquarter in Stuttgart and goes to the Bosch-Test-Drive-Center in Boxberg , 19 miles away from home, (with an oval-highspeed-roundcorse like the NAS-Car Stadions, and several different areas for testing and developing with all technical equipment and stuff). The event is called Boxberg-Classic, see (www.bosch-classic.com). The visiting is for free, and every oldtimer-enthusiast like me, has the chance to see many Oldtimer (nearly 100-150) and talk with their owners, but there has never been a TR7, so i hope to participate next year.
I also still have to repair the AC-Components, especially the heater and the tubes, that's why the car doesn't run since last summer.

cheers Roger

[Hasbeen]

I know one of our Triumph specialists uses Bosch gear to get the injection in TR6 systems working properly. Perhaps the Lucas gear is mostly patterned on the Bosch.

Hasbeen

[HDRider]

I have used Bosch part number 11027 in the past with success. They are described as "Universal" fit. They looked like what was in the car with the exception of the short lead wire.

They are available from Amazon.

Edward Hamer
Petaluma CA

[darrellw]

I know one of our Triumph specialists uses Bosch gear to get the injection in TR6 systems working properly. Perhaps the Lucas gear is mostly patterned on the Bosch.

Hasbeen

For the Wedge, the FI parts are Bosch, in many cases with just a Lucas label stuck on. The major exception is the TR8 ECU, apparently Bosch didn't have one for a V8 at the time, and Lucas did their own.

[FI Spyder]

I know one of our Triumph specialists uses Bosch gear to get the injection in TR6 systems working properly. Perhaps the Lucas gear is mostly patterned on the Bosch.

Hasbeen

I talked to a TR6 FI last year, they weren't imported into Canada not making the emission standards of the day I guess, but he had an English system, they were Lucas mechanical setups. He said the only maintenance he had to do was replace the injector rubber seals and switch out the Lucas high pressure fuel pump for a Bosch one. I assume this is what you meant about Bosch getting a Lucas system to work?

[Stag76]

It will most likely be a single or 2 wire narrow band sensor that outputs between .1 and .9 volts.
If it has 2 wires, the white one is normally the signal, and the black one is ground.
A narrow band sensor only indicates that the AFR is over or under 14.7:1.
The most commonly used thread is 18X1.5, and bungs with this thread are readily available.
Alternatively, you can weld a nut with this thread into the downpipe, and you can then use any
universal narrow band sensor.

The positioning of a narrow band sensor in the exhaust pipe is not critical.

[FI Spyder]

The positioning of a narrow band sensor in the exhaust pipe is not critical.

I have read that it is critical (at least somewhat). It has to be with in a certain temp range and if you are using headers it has to be placed forther down the pipe as temps inside headers moves down the pipe (less material to heat up and dissipate the heat externally or the more efficiency causes the heat temp to go further down the pipe?) Don't know as to the validitally of article, just what I read.