help v8 coil question

Hi as from my last post i had a look into the wiring again and found that I have power to the wires to coil when they are disconnected from coil reads around 11v. when I re connect them to the coil I have no reading and the wires that go to coil are black single and white n blue going to two suppressors I presume . The black wire I presume is earth and reads as an earth but when connecting meter across the two wires the voltage is reversed ie -11v . Can any one shed any light on which wire goea to coil + .

I didnt see your other thread so dont know wot set up you are running

look on google image for help with diagrams , you get stuff like this

this is what mine looks like before putting a new coil on it

depends ,coil has no earth only a + feed and a - to points if points system, if 12v coil it should have 12v feed if ballast resistor 9v feed 11 would show poor resistor or poor battery feed ,if electronic dizzy it would have 12v feed and one wire to + and one to - from amplifier

Hi guys sos took awhile to get back . I finally found the power spark distributor was faulty yet again . Now I have a replacement on shes running sort of ok . Starts after about 3 turns over of engine and goes like stink but when warm it hates starting so I might put my old distributor back on the one with points as she seemed to start better with it on as apposed to the electronic dizy .any comment from you v8 guru's .

I'm not so good on older V8's with carbs but the pic you posted shows the HT lead routing is incorrect. make sure the leads are properly routed and clipped. You might also think about checking the HT leads for arcing, check at night, engine running, check for sparks.

As for not starting, check ignition timing and maybe do a compression test. Check for air leaks. When were the carbs last serviced?

HTH

Hi classic key thats not my photo lol. Mine is a efi . I have managed to get runing and use it without ringing the rac lol. I found out after a lott of fiddling it was the uprated coil and dizzy from power spark so I got it replaced and now it runs all be it on nearly 16deg advance . But starting is a pain esp when hot . What I would like to know is whats better the old dizzy with points or the new electronic one from power spark . Now im prob answery own question .the old one starts perfect and runns ok . Just wondering what peoples thaughts was .

If it is an original efi motor it should have electronic ignition.The ignition timing you say is way too much advance. The RV8 is pretty tolerant but the stock timing should be much less, something like only 4 degrees but it does vary slightly depending on the year and the compression ratio. What engine is it - 3.5 or 3.9? you running hot wire or flapper? What compression ratio is the engine?

I don't know anything about "powerspark" but again if it is an efi motor, I remember seeing something years ago that suggested never to use a "performance" coil.

Have you done a compression test?

You say it doesn't want to start when hot - check the resistance of the temperature thermistor, if the ECU doesn't know the engine is hot it might be putting too much fuel in. The alternative may be too see what happens when hot if you try to start it with the throttle wide open (it might flood so make sure your battery is strong as you'll need to crank it a bit to clear it). If it starts a bit quicker with some throttle I would suspect a dicky thermistor. One other thought though, if yours is on flapper has the cold start injector been disconnected? if not take off the fuel supply pipe and plug it so it doesn't leak and give it a whirl. HTH

powerspark stuff isn't great.....I had it on mine but now its all Lucas and running about 6*

Dr_evil said:

powerspark stuff isn't great.....I had it on mine but now its all Lucas and running about 6*

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I would think it runs alright at 6 degrees, RV8's seem quite tolerant to advanced timing, I have played around with mine just for laughs and certainly 8 - 10 degrees is possible, certainly faster throttle response but overall I have found sticking to factory spec gives good all round results.

the low timing number ie 6 is to keep a stable tick over,it advances as revs increase..max advance is still rather low, this in my oppion is to allow for crap fuel to be used..engine will easily take more advance if running lpg or high octane petrol..ie above 91
also..a low advance at tickover allows the ecu to detect idle dropping, say a/c comes on etc and to beable to advance idle advance to give a boost in power output at idle,hense stabilising idle..
so high advance timing is not so good.poor idle and ecu cant adjust...keep below 12 degrees..

Thanks guys its gave me a few things to think of now im definitely going to put my old dizzy and coil on Cause I know it ran ok on 8deg adv .ill give the uprated one the boot . Oh its a 3.9 hot wire system its a 1998 and I did a compression test before I did a rebuild and they was all very similar . The rebuild is another story .im going to have to do it again this time with new valves.

Not sure if last post went through butThanks guys it sound like the uprated dizy is not the best answer so its comming of and im putting the old system on . Oh its a 1998 3.9 hot wire system and I did a compression test before I rebuilt the engine cause it had a tapping . Im going to have to do again lol but thats another story I dont want to bore u guys abt. Hopfully its dry tom so I acn refit the old dizzy and give plugs a clean .

it did