I'm wondering whether the extra energy is also over heating my spark plugs too when running normal gap sizes.Jack Bauer said:
These questions I'm going to answer by research and testing. Anyone already ahead of me on this then please jump in
Best Leads
- Thread starter hmmm
- Start date
These questions I'm going to answer by research and testing. Anyone already ahead of me on this then please jump in
antgtir
New Member
Jim your right mate, the electrical system if uprated must have matching rated parts i.e. just like stereo design, if the system has amplifiers pumping out much greater power than original, the cabling transmitting that power also has to be uprated to suit the transmitted power.
Therefore if the elctrical ignition system on a car is uprated so to should the leads and rotor arm and dizzy cap etc. Just how far you are able to go with the parts available on the market today is unknown to me, maybe the likes of Rishi and AJ4 will be the first to experience this with the kind of power figures they are gunning for?
Ant.
Therefore if the elctrical ignition system on a car is uprated so to should the leads and rotor arm and dizzy cap etc. Just how far you are able to go with the parts available on the market today is unknown to me, maybe the likes of Rishi and AJ4 will be the first to experience this with the kind of power figures they are gunning for?
Ant.
Just found this interesting post on wires:
http://www.stealth316.com/2-msd-ignwires.htm
The Stealth 316 forum has some wise people on it so I trust the source. They do go in to the science of how things work in detail.
I now understand why my Magnecors were casuing me problems at the limit of my OE ignition system. I'll check the resistances myself later.
I am left wondering what system the Magnecors should be matched too?
Edit: Blimey, ready through a few more threads on the stealth 316 website, there is a lot of knowledge there and compared to 2 posts ago I'm much wiser. If your head doesn't explode first, have a read through.
http://www.stealth316.com/2-msd-ignwires.htm
The Stealth 316 forum has some wise people on it so I trust the source. They do go in to the science of how things work in detail.
I now understand why my Magnecors were casuing me problems at the limit of my OE ignition system. I'll check the resistances myself later.
I am left wondering what system the Magnecors should be matched too?
Edit: Blimey, ready through a few more threads on the stealth 316 website, there is a lot of knowledge there and compared to 2 posts ago I'm much wiser. If your head doesn't explode first, have a read through.
Last edited:
A
AJ4
Guest
I still dont understand why people are having problems with the standard ignition system. Your rev limit and whether you can charge / discharge enough power in that short time is what governs what ignition system you use. The standard Nissan one should be good for 8000rpm 'ish. Yes, you need a slightly stronger spark if your running very high boost, but your rev limit is by far the deciding factor.
I'm not sure exactly why Ross, I know the limit of my last map was down to misfiring at high rpm around 1.8Bar with a 5mm plug gap
I want to do a bit more learning and testing before I comment on the why for my particular problems.
I want to do a bit more learning and testing before I comment on the why for my particular problems.
A
AJ4
Guest
Are you absolutely positive the misfire was down to the ignition system ? I'm not saying it wasn't I'd just be curious to know why it happened.
What were the sypmtoms that pointed to it being a misfire, as opposed to running lean, detting, dizzy problem etc ?
What were the sypmtoms that pointed to it being a misfire, as opposed to running lean, detting, dizzy problem etc ?
They told me :doh: In fairness, they told me thay had problems with the magnecor leads before mapping the car. They found problems they fitted some standards they had around wnt off and mapped it again and got the final 0.2bar without misfires before they said they had the same problem with high rpm misfire.
BTW, I agree with your charge/discharge comment and my logic is that was the limit I was hitting. If it was voltage, you could just reduce the gaps again. My explaination (not backed by science, tell me if I've misunderstood) is you need more energy to ignite the denser mix at the same rate
TBH Ross, as soon as I can get my blooming datalogit to work, the map will be PM'd to you for a second opinon. Failing that, I might just type it all into excel
One thing I'm interested to know is what the OE coil is rated too in terms of secondary voltage. I'm wondering if a standard plug gap (Said to be alright by a user on SR20 in a similar application) even with the fancy ignition system is compounding the issue.
got to say I'm glad someone else is thinking of putting in time in their own research of their cars, just got mine running set base idle, ign' timing to 15' ( untill run in and V power in tank ).
I'm waiting to get a capacitive pick up for KV test and going to use my autoscope to check coil charge time, especially interested in 8000 RPM to see what the Duty % is at, to see if the charge time can be increased and then how long before it fails.
Does anyone know the coils turn ratio?
I'm waiting to get a capacitive pick up for KV test and going to use my autoscope to check coil charge time, especially interested in 8000 RPM to see what the Duty % is at, to see if the charge time can be increased and then how long before it fails.
Does anyone know the coils turn ratio?
Last edited:
A
AJ4
Guest
What sort of revs are you hitting ? I wouldn't have thought you'd need anything fancy like capacitive discharge unless you were regularly going over 8500rpm or so. If the misfire is caused by the high rpm, no coil or leads in the world is going to help, its how quick you can saturated and fire the coil. A bigger coil would probably just make matters worse, ie, longer charge / discharge time.
0.5mm gap does sound a tad small, even at that boost level, are you sure its not too small ? The small area of the spark coupled with the small duration could be causing the misfire.
Whats wrong with the datalogit ? anything I can do to help ?
0.5mm gap does sound a tad small, even at that boost level, are you sure its not too small ? The small area of the spark coupled with the small duration could be causing the misfire.
Whats wrong with the datalogit ? anything I can do to help ?
A
AJ4
Guest
just had a quick look at the manual, primary = 1.0 Ohm, secondary = 10 KOhm, so 10000:1
I've got my standard limit set to 7500rpm, I rearely hit it with the G-Tech guiding me but whilst overtaking the other day I ignored it and bang on 7500rpm the limiter came in (abruptly!!!!!) I'm now thinking of putting it back to normal (8200rpm, is that right?) so I have more time to react when overrevving slightly.AJ4 said:
For me the advantage of CD is it keeps a big lump of charge available and throws it at the primary as soon as the coil discharges. Belt and braces really. It does allow you to run a bigger coil (BandB again). I paraphrase here but I still want to get some of the science clearer in my head. In fact, whilst you're on
, why is too small a plug gap "bad", all sites seem to cover too big gaps in detail but then skip over the too small bit. Voltage is irrelvant once the spark has sparked but there seems to be a lot of bad science around concerning spark "size"Gap wise, I'm thinking of moving to the 0.65 recommended by Ed rather than standard or the 0.5. Aside from the fact that its in the middle, it means my ignition system is closely aligned with Steve's MSD system.
On the datalogit, its serial comms and as my laptop doesn't have a serial port I'm having to use the base station that has worked before but there might be something I'm missing. I'm pretty good with computers but thanks for the offer.
The thing is I'm finding the install of my Din Sized car PC in my other car far more interesting (geeky) a project than the R at the moment so the poor thing has been taking second place for a while now.
sypher said:I'm waiting to get a capacitive pick up for KV test and going to use my autoscope to check coil charge time, especially interested in 8000 RPM to see what the Duty % is at, to see if the charge time can be increased and then how long before it fails.
quote]
I had previously put a scope on the primary coil but only upto 2Krpm. Was still intersting to see in a sad geeky kind of way. BTW, I have this mental image of you looking at the scope with wires going to the bonnet whilst bouncing off the rev limiter :lol: . The things we do for science.
Was also just looking back at the thread, I bet "hmmm" only wanted a use Magnecor cables type answer. Unfortunately this thread has been hijacked by me
:yield:
Jim, why not just get a serial to usb lead like I did with it ?
I recently had my motherboard changed on the works laptop and there is some quirky hardware fauly going on now. I spent a few hours messing with the BIOS, XP and ports and then sacked it off and spent less time typing it into excel.
Steve, I'll do what you suggest. Which brand did you buy as I know some can be a bit random in their performance.
I never quite got round to checking the resistance of the leads but will get round to it for reference.
Steve, I'll do what you suggest. Which brand did you buy as I know some can be a bit random in their performance.
I never quite got round to checking the resistance of the leads but will get round to it for reference.
re. plug gap
Interestingly enough, when Ed and I mapped the car on Saturday I had Denso IK27's set at .63mm but on return to Ed's place I set them to 7, now I know this shouldn't really make any difference at all, if anything make things better but on the way home the car hesitated and hiccuped and enough to make it unpleasant to drive. When I got home I reset the plugs to .63 and all was fine again :?
Very strange !
Anyway I have now ordered the (recomended over the Blaster SS coil) MSD HVC Blaster coil, so we shall see if that changes anything.
Interestingly enough, when Ed and I mapped the car on Saturday I had Denso IK27's set at .63mm but on return to Ed's place I set them to 7, now I know this shouldn't really make any difference at all, if anything make things better but on the way home the car hesitated and hiccuped and enough to make it unpleasant to drive. When I got home I reset the plugs to .63 and all was fine again :?
Very strange !
Anyway I have now ordered the (recomended over the Blaster SS coil) MSD HVC Blaster coil, so we shall see if that changes anything.
I used a lead I bought from Maplin which did the job fine.campbellju said:
A
AJ4
Guest
the smaller the plug gap the less 'contact area' between the spark and the fuel, the ideal is nice long spark with long duration for best efficiency. Anyhow, don't really want to discuss it on here as it'll only turn into another 'who knows best' pissing contestcampbellju said:
PM or MSN.
Last edited by a moderator:
www.performanceleads.co.uk
Give these guys a try. 8mm silicon insulated leads with a spiral stainless steel conductor (ala Magnecor). And about half the resistance of the OE Nissan leads. All for about £25.
I've got a set and they are very well made (to order) and work as expected.
Can't argue with that !
Give these guys a try. 8mm silicon insulated leads with a spiral stainless steel conductor (ala Magnecor). And about half the resistance of the OE Nissan leads. All for about £25.
I've got a set and they are very well made (to order) and work as expected.
Can't argue with that !
Mine seemed fine at 0.65mm and even at 0.7mm it wasn't a noticable drop but at 0.75mm, standard, I too thought it was lumpier than ever. I had fitted my magnecors back again too though at the time :roll: I'm pretty sure I'd been past 0.75mm before on the OE leads so there's some more data but it needs a little more careful research. I'll get my multimeter out tonight when my wife goes out...... I'm sure other people have affairs and things when their wife goes out. Is this living in the fast lane or what :doh: :lol: :lol:stevepudney said: