scoooby slayer

iTrader: (4)

if i fit a snug fit 6 " long exhaust pipe in my cars tailpipe, with wideband sensor in that clamped to exhaust, is it as accurate at wot for a/f readings compared to downpipe ?

Rick

for WOT runs, yes.

scoooby slayer

iTrader: (4)

well i just got in have made this up for tmrw, what ya think ?

its a msd lambda slug so should be sitting in the right position.

bad boy rs

iTrader: (7)

What does wot mean ?

Mark Shead

It wont work the pipe is to large and to short.
Drop it down to about 1.5inch and over 12 inchs long so it sits inside the box as it will pipe up air at high rpm.

Mark

Rick

As Mark - it's too large in diameter. I now know what you mean by snug fit - it shouldn't be like that, it needs to be much narrower. Much less likely to get contaminated with fresh air.

Rick

andy escos

iTrader: (1)

wide open throttle

J1mbo

iTrader: (1)

6 inches from turbo in down pipe, where we always put the sensor

Rick

He's going to struggle doing that with a length of pipe in the exhaust!

scoooby slayer

iTrader: (4)

ah well if it goes lean then it could be fresh air lol

il try it in the morning if it fucks about i guess il have to start again.
thanks for letting me know peeps

J1mbo

iTrader: (1)

Bit of flex tube! Whats up with ya

Jimmyc

Will the tailpipe get hot enough for the lambda to work properly?
Or is it an electronicly heated lambda jobby?

scoooby slayer

iTrader: (4)

it was in the middle of car on skyline and was consistently accurate at 11.4 wot.

Jay,

iTrader: (4)

mate it wont read right like that i did the same with my skyline it was shit so fitted it like jimbo said

Big Will_

If you're going to remake the pipe as per the above suggestions... I'd also recommend you put the sensor either upright or 90 degrees either side of.

Having the sensor at an angle lower than that can cause moisture to settle inside the sensor and as you can imagine, sensitive heated elements and moisture aren't a happy combo!

scoooby slayer

iTrader: (4)

well it did work but only at certain rpms i think so ive made this up now as suggested, 1.6" pipe hopefully be more stable, thanks mark

andy escos

iTrader: (1)

your welding skills are awesome if you do put a lambda in the down pipe please get some one else to weld it

ps awesome car .

scoooby slayer

iTrader: (4)

lol to put it in perspective mate the welder i used has 1mm wire on heavy argon. i weld up 1" plate normally, should of used my 185 amp but couldnt be arsed to change the gas over.

Mark Shead

I would use a jubily clip round the pipe holding it to the exhaust also, I have seen one come off without these.

Mark

scoooby slayer

iTrader: (4)

i dont know why but it was worse with the smaller pipe ? reading all over the place ?

Mark Shead

Make the pipe longer so it goes further inside the exhaust box,
Big tail pipes will pull in air at high rpm.

Mark

scoooby slayer

iTrader: (4)

the smaller pipe was about 14" in the tailpipe though its up in the rear silencer. do i need to get even further in there then mark ?

Mark Shead

Yes I think from mem mine is 18inhcs, But also watch where it sits inside the box,
On a Escort cos place it on the right side of the pipe it can change reading as it sits at a angle to the baffle tube place it on the left and fixes it,
With a 2.5inch baffle tube on the same car you cant use the tail pipe ext as it sucks in in to the back box.

Mark

scoooby slayer

iTrader: (4)

my silencer has 2 2" ports in the box as its 2 into 1 underneath car into a 5" backbox. i guess i could try and get through behind the back box into pipe again, but which pipe do i go in as it ts off into 2.

on the big pipe it was cruising at 14.7 stable then on part throttle as some boost came in got into 12s then 11.1 at wot but then showed going mega lean from 6k revs up, 17 afr lean which was no way accurate.
il put it this way when i removed the 1.5" pipe earlier it was pure black with soot from just a few pulls up the road lol its nice to be sure though thats its mega safe.

Stu @ M Developments

iTrader: (12)

Your going to struggle a bit with that ridiculously large tailpipe mate. We have a slightly conical one for those so the inlet is larger than the outlet, helps a lot, but what helps most is having a sensor that actually shows when its got fresh air mixing in with the sample so you know to ignore it..

Stu @ M Developments

iTrader: (12)

Many a monumental blow up has started with those words... LOL

Mark Shead

Weld a bung in the front this will be the best way.

Mark

J1mbo

iTrader: (1)

Put a boss in the down pipe mate I really would

scoooby slayer

iTrader: (4)

downpipe is 5" too its mahoosive
the readings massively changed for the worse on the smaller pipe so pipe is causing issues for sure. what about if i had a pipe that was sealed inside the back box with a good 18" of pipe behind the probe ?

scoooby slayer

iTrader: (4)

there is a lambda sensor in the downpipe already, on the ecu af feebback is switched off, so i guess in theory i could just remove that and put my lambda in there tmrw. even if closed loop was active its still errelevant to wot anyways so i guess i should just do that tmrw.

Stu @ M Developments

iTrader: (12)

<---- in the politest possible way.

scoooby slayer

iTrader: (4)

i tried turning af feedback on but lambda output still shows as 0 on display and fueling doesnt change at all on my sniffer so i guess the current lambda isnt actually connected to the ecu for some reason ?
so it shouldnt hurt anything then stu if i just remove the lambda and screw my wideband in there and run up the road.

J1mbo

iTrader: (1)

If it's in no way used then yes but be sure!

Best place to put the sensor anyway

Gav Diamond

iTrader: (6)

You have a engine that is running 900bhp and will no doubt be very very expensive to replace should something go wrong.....why not just spend £10 and get a proper lambda boss off Stu and get it welded into the downpipe so as not to remove a part that could be doing a important job..