Spark Plug Gaps.

[Corey]

Hello , Basicly.. 1.2 Cat version says 1.1

but what if u have the cats removed but its still a super s 45kw model do you stick to the 1.1 gap for better spark and power.. or put it to 0.9

and same goes with the timing.. what setting should i be looking at ive removed all cats and got a 4-2-1 manifold and got a standard LX carb on and not got the super s ecc one .

its either going to be 3° ATDC - 2±1 ATDC CAT MODEL or 0±1 BTDC Non Cat
No Vacuum Readings

i think the car is set ATDC atm by the guys thats tuning it i just want to do some research

thanks

 

[porkpie700]

You don't need to change the plug gap. They come pre-set, for a better spark there are higher spec plugs available i.e. use BPR6 ES plugs instead of BP6 ES (NGK's), or use irridiums. Also uprated coils, spark leads and addition earth points to the engine will help to improve the spark, but only to a point.
The plugs are nothing to do with the exhaust system and changing the exhaust (like removing the cat) does not affect them so there's no need to adjust them.

 

[Corey]

thanks .. but the plugs i got now aint gaped and they are new .. i have the denso iridium power untill they died for some reason!..

i got the ngk v groove ones the recomended for my engine and cars fully modified mate im not some noob i was just being curious , i just wanted to see what people thought but ill set them to 1.1 again cuz ill get a good spark

 

[porkpie700]

Denso plugs are trash, i've never had a good denso they've all been crap. NGK's are supposed to be pre-set, you just put em in right out of the box. They should normally come gapped at 1.6mm give or take .1 either way. But anyway as you say, set them to what you know works for your engine and it should run quite happily.

 

[Corey]

ive found with the boost pressure sensor that if u unplug it the engine idles up and does not advance or somthing as the car becomes powerless but thir must be a way of re doing the wiring to remove it corretly.

 

[frank]

ive found with the boost pressure sensor that if u unplug it the engine idles up and does not advance or somthing as the car becomes powerless but thir must be a way of re doing the wiring to remove it corretly.

you,re gonna loose a lot of power with no vacuum advance fwn

 

[Corey]

the guys blocked it all off and i gained power it advances electronicly and using the crank sensor or dynamic balencer or flywheel .. he seems to know what hes doing and hes not finished yet ..but i was just having a play around and unpluging it did that above^ .. ill talk to him but it might just be a case of either rewire or re timing

but im thinking because of all the ECC carb and EGR out nothings original and the loops and connections are not the same without the old airpan so .. making it standard apart from the dizzy is probbaly a good idea.. ?

 

[frank]

yes you,ll have rpm advance, but you wont have any load retard (vacuum advance)
so you,ll loose power because you,ll have to run extra retard in order to avoid pinking under load

 

[Corey]

humm he said it cant have both with the setup i have it dont work.. no original carb and that .. it looks like im going to have to get a standard dizzy..

i dont think the boost presure sensor does out nothing changes if u block the pipe or not but unpluging the wires does at the moment..

cheers

 

[RTLkyuubi]

I would like to help Corey but I cant understand most of your posts? You say your not a noob, but yet it seems that you do not know what your talking about (unless your having difficulty because your not english) also changing the plug gaps that much will make #### all difference. But ignition timing will. Even though you have a non ecc carb, your ignition still uses ecc and needs all the sensors to alter it correctly for the engine.

The easiest way around for you now is to get a standard vacuum advance dizzy and get completely rid off the ecc system.

 

[porkpie700]

True, with some of the sensors unplugged the ecu is no longer getting all of the info it needs to decide what the best ignition timing will be for the engine. So it will just assume something is wrong and use a fixed pre-made setting, kind of like going into a safe mode.

 

[Corey]

im english just cba with typing too much.

and i know certain things but still learning and ive done more than allot of other people with k10s, its just i hear different things from people and now this guy thats tuning it which ill be seeying him tomorrow..

i think i might go for the standard dizzy.. but not too sure,

the T piece at the back of the manifold the other side goes to the carb but the guy said its pulling in air from that too inlet and causing problems so he blocked everything off and kept the Boost pressure sensor wires plugged in and timed it up to TDC.. and set the idle and it was improved from when i took it in.

 

[Corey]

oh and spark plug gaps are pretty important actually, if the gap is too large you will get misfires in high revs and bad cold running, and starting problems..

and too close produces a weak spark .

 

[RTLkyuubi]

im english just cba with typing too much.

and i know certain things but still learning and ive done more than allot of other people with k10s, its just i hear different things from people and now this guy thats tuning it which ill be seeying him tomorrow..

i think i might go for the standard dizzy.. but not too sure,

the T piece at the back of the manifold the other side goes to the carb but the guy said its pulling in air from that too inlet and causing problems so he blocked everything off and kept the Boost pressure sensor wires plugged in and timed it up to TDC.. and set the idle and it was improved from when i took it in.

.

I cant really help with the vacuum pipes as I never studdied the standard carb that much to see which one was for which. But I do know that you need one for the map(boost) sensor / dizzy (depending on which one you have)

But the haynes manual says:

for the hitachi dcz 306-81, you need:

1 vacuum pipe for the idle compensator (the metal thing in the air pan)
1 vacuum pipe for the vacuum break diaphragm

Looking at the pictures (12.6 on page 78) there are only 3 vacuum pipes which would be the 3 above but im not certain

oh and spark plug gaps are pretty important actually, if the gap is too large you will get misfires in high revs and bad cold running, and starting problems..

and too close produces a weak spark .

to get it to misfire you would have to have like a 4+mm gap and to close would be touching .1mm in a spark plug gap wont make any difference.