4722 replies to this topic

[chris_uk]

what is 0.711 gap , its an odd mm size and not even imperial either  , 0.65 , or 25 thou

0.711 of a mm

[Nev]

Hmmm, the problem is still there albeit slightly improved by the new plugs. I did a bit of "diagnostic driving" and the stuttering only seems to occur when applying light throttle when running on an inlet vacuum. Also it only occurs when under 2250 RPM (the engine runs really well when booting it above 2500 RPM).

 

So these 2 symptoms are making me think the lambda sensor (which is used for idle/light throttle control) might be a bit screwy, particularly as it's still the same one the factory installed 15 years ago and it's cable runs right next to the exhaust! Also it's meant to be a 100,000 service interval swapped part and it's seen a lot more heat than a normal Z20LET makes. So I'm about to order a new one.

 

It's quite fun doing some diagnostic work, Nipper has been far too reliable for 4 years! (now I've gone and said it!)

 

 

Edited by Nev, 05 April 2018 - 12:38 PM.

[siztenboots]

 

what is 0.711 gap , its an odd mm size and not even imperial either  , 0.65 , or 25 thou

0.711 of a mm

 

 

yes obviously mm , but who has a 0.711 feeler gauge

[chris_uk]

I do.

[Nev]

I think it might be time for a Spring clean.

 

[The Batman]

Im about to clean all the mud off my car

[Mattyboi]

Thats awesome! Dirty fast cars look so right! You seem like you could use some lazy mans detailing stuff like I've been using. Carbon Collective Hybrid is some kind of ceramic coating you put on with a jet wash after a clean and just blast off with water. It gives 2-3 months decent protection so you just need to jet wash the grime off. It even does the "beading" thing VW detailer types like to post pics of. Cant recommend it enough*.

 

*I've only ever used this so probs loads of similar stuff about.

[Nev]

Im about to clean all the mud off my car

 

I think you should leave it dirty (like your mum ). Everyone know that cars and women grip better when they are dirty.  

Edited by Nev, 05 April 2018 - 01:45 PM.

[The Batman]

 

[Doctor Ed]

what tyre size are you running Nev?

[Nev]

what tyre size are you running Nev?

 

Currently 225x17x45% front and 285x18x30% rear. I had 245x18x35% fronts for 5 years, but it tram-lined too much and I need more tyre % profile for the type of road I drive on, so I have come down a size in diameter in and width, but increased profile %.

 

I understand Lotus copied my wheel sizes for their new car.

 

As a general principle (for road driving) I'd recommend keeping as much % profile as possible. The problem is, that desire conflicts with wider wheels often, which is clearly the other salient objective.  

Edited by Nev, 05 April 2018 - 03:06 PM.

[Chris P Duck]

Im about to clean all the mud off my car

  I think you should leave it dirty (like your mum ). Everyone know that cars and women grip better when they are dirty.  

My Mrs gets fussy about cleaning once a month. Nice to see your cycles have synced up

[BadCop]

I do.

 

you dont.

 

measurering one µm with a feeler gauge - lol

 

saying it was 0,71mm is already beyond honest measurement uncertancy.

claiming 0,711mm is utter bullshit.

[Zoobeef]

Feeler gauges come in sets with 0.028" - 0.711mm in them. Yes you aren't going to be able to feel to a thousandth of a mm but doesn't mean chris doesn't have a gauhe with that written on.

[BadCop]

Maybe it's written on it but he still does not have a gap of anywhere near that. Take a second gauge and measure To really measure the distance send the gauges and gapped plug to my place, we can measure 1 micrometer. We have a Werth measurement machine over 200.000 £ to measure within an error of 1um. Not that anyone would need that kind of precision with sparkplugs. But you will See that those feelergauges have an error of over 10um and the gaps even more. Thermal expansion alone will cause over 30 um. 0.7mm +/- 0.05mm would've been an honest number what you can tell from using those feelers. Claiming 0.71mm is already far away from the truth. But 0.711mm is just like a satnav that give you distances in mm.

[Zoobeef]

I dont think anybody really cares about your machine. Chris has just said which gauge he uses.

[chris_uk]

Erm.. i have a feeler guage which says 0.711mm on it. I edit the gap until it takes a tint bit of force to pull it out.. i put the 0.8xx in and its too big, i put the 0.6xx one in and it slips in and out.. the 0.711 just slides in nicely with a tiny bit of friction... Im not saying its accurate.. but it did make a difference between it missfiring and it not.

[BadCop]

Yep, then 0.7mm is the technically correct term for your gap.

Any more digits make no sense.

 

 

 

[Doctor Ed]

i thought chris was just being sarcastic :/

[Nev]

It occurred to me that just prior to getting my strange low throttle hesitation issue that I'd been making some tiny adjustments to the cold start routine in the map. So tonight I went in the garage, got the laptop out and loaded up an old "pops and bangs" map I'd made about 2 years ago and wrote it (ie a full overwrite) into the ECU and went for a drive. Amazeballz, as this seems to have cured the problem completely, which is strange as I hadn't thought I'd fiddled with anything significant to have caused the problem in the first place.

 

I could really notice the higher ambient temps this evening, probably 12 degrees here, whereas for the the last 3 months it's been more like 0 degrees when I've been going out. The extra front end grip is noticeably better, I even flicked my dash switch for a "full torque" (430 ft/lb) squirt, just to hear the boost hissing down the pipes! Roll on summer with 30 degrees and superglue handling!

 

Went to Castle Coombe "Action Day" (read: "Carnage Day") today, mainly to meet Phil in this VX220 and have a snoop round it. He's put a B204 into it (which cost him £150 for the whole engine)!! He's only got the titchy Saab turbo on it still, but if he swapped this for a bigger unit it would be a 500 HP engine. Incredible value for money, though of course you need the skills to do such a thing; hats off to him. He has his screamer pipe pointing out of the top of the rear boot lid which is somewhat novel, must be "entertaining" for anyone fast enough behind him to see flames shooting upwards out of that!

 

Off out to Wales at 5.00 AM tomorrow morning. Brrm brmm.

Edited by Nev, 07 April 2018 - 08:24 PM.