To AFR or not to AFR

Hi all

So I'm nearly done up to BPU and I bought a cheap AFR gauge as part of it a Juding I believe. Do I just connect it to the o2 sensor or buy a sensor and fit at the end of the decats? Do I even need one at normal BPU at 1.2 controlled by a HKS 6 BC?

you don't need one at bpu , you also have to buy a weld on adaptor to fit the wideband o2 sensor anything else is not worth it mate , if you do it that is

Even at 1.2 max I'm safe then?

When you say cheap, what gauge did you get?

Is it a narrowband gauge designed to work with the stock sensor, or a wideband gauge supplied without a sensor?

Hiding it was about 40 quid. No sign of any sensor just gaugecand 4 coloured wires

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Sorry I meant Juding

Can you post a pic or link to it, quick search doesn't bring up anything useful.

If it doesn't come with its own wide-band sensor, its unlikely to be wide-band, and so if narow-band its practically useless and not worth fitting, as all it will do is tell you if its rich or weak, and not by how much, and that is only during open loop, the rest of the time it will just fluctuate from rich to weak as the ECU reads the std lambda sensor.

But if I am at 1.2 controlled with the best BC you can buy the HKS6 and the best FCD you can buy, from CW, the best restrictor you can get, WB, I should be ok yes? Bearing in mind I have new cambelt, new valve seals, new FMS, new oil pump, new fuel pump, new sparks, new filters, hell half the car is new now? I have been told I'm fine but as a precaution to fit AFR if I want, is that the gospel?

If you want to fit a decent wide-band AFR gauge then fit Innovate or AEM, having what you call the best boost controller and other ancillaries is fine but all that matters is the AFRs, most BPU motors are usually fine because the ECU will run the injectors at 100% duty cycle when over original peak boost and/or WOT so in theory there should be enough fuel to keep AFRs within safe area, personally i always fit one, and since you have now spent all that money on your motor i wouldn't be skimping on a couple of hundred quid more and being sure the motor is safe.

Its a Juding LED9959 and comes up in google and as I say no sensor on the end. To be honest I nly bought it because I liked the LED dial itself and just assumed if it was touted as AFR it would work as an AFR. Its amazing how often products are disappointing isnt it. I bought the full stainless dash trims and one of those custom made to fit a Supe doesnt. I wonder where all the QC people in the world are sometimes.

Searching in google for that I cannot find anything

I couldn't find any reference to it on Google ether, i suppose its just possible that its a gauge sold separately and you have to add the wide-band controller and sensor, can you post up a link, that way we can give you a definitive answer.

http://www.rakangertai.com/proView.asp?id=943 This is what I found on google, but no actual useful info, as I say leads to 4 coloured wires at the back, so I am guessing you need a sensor. Considering the sheer amount of money I have spent getting the best of everything for BPU I reckon maybe one of the 150 quid market leader AFRs is perhaps the way to go then? The car is in for its new fuel pump on the 26th, then I have to fit new dashboard cluster glass and last of the new trims when that arrives on the 30th so I guessed the dash out day was the time to fit this AFR but if its just going to give micky mouse readings then need a rethink. I havent fitted the CW FCD yet or BC because I wanted to monitor AFR before going above 1 bar to make sure its all setup healthily. Is my new policy of doing the sensible stuff first, making sure its reliable then moving on to the next part, an alien concept for someone used to 'respray, big wheels and foot flat down' of times gone past....

If anyone is interested the WB restrictor ring I got is just superb, literally goes to a nadge under 1 bar but still safe under FC at full chat straight out of the box at least according to my blitz boost gauge.

Couldn't actually find the gauge number you list, but looking at the others they are not wide-band, so i would just sell it on and buy Innovate or AEM and get a lambda boss welded into the exhaust to take a wideband sensor, then your set up for any future mods and can know exactly if AFRs are good.

https://www.innovatemotorsports.com/products.php

https://www.aemelectronics.com/?q=products/gauges/wideband-uego-air-fuel-gauges/x-series-wideband-uego-afr-sensor-controller-gauge

When does possibly high EGT's come into this? All I'm thinking is safety and having a less than 1 bar restrictor ring (do we know what exactly it is right now?) and then bumping up to possibly 1.3bar?

It brings me back to the boost controller issue, if you end up running it at 1.2-1.3 bar most of the time in the end then that restrictor ring is just raising your egt's isn't it? it has no use other than if you switch the boost controller off boost lowers back to the less than 1 bar (perhaps a useful winter mode!?).

EGTs are directly related to AFRs as a richer mix will lower EGTs, so as long as its doesn't go lean at max boost pressures and load it should in theory be fine, the restrictor will be far less restrictive than a cat so shouldn't be an issue, valve an ignition timing will play a far larger part in raising/lowering EGTs after AFRs, but as std shouldn't cause any issues.

I fitted an EGT gauge tom mine as soon as i went BPU and found nothing to high, then went hybrid turbos and fitted WI and EGTs where never anywhere near high.