Havin Abit Of Trouble Startin The Mi!

[yorkdave 1]

it finally came to the point where i had to try to start my mi, to give you a breif spec it is an alloy 1.9, three angle valve seats, R1 bike carbs, lightened and balanced bottom end, fully rebuilt with all new liners, rings, shells, and running on the 8valve ignition with an adaptor. you should note that i rebuilt it, i'm a mechanic and know roughly what i'm doing, but a pro engine builder i ain't! it is getting fuel (at a lower pressure, about 2psi) and it is gettin a spark (have used some spark tester which flash) the firing order is correct, i think the only reson it won't fire is the ignition timing. It is back firing through the exhaust and some times the carbs depending on where i put the dizzy, i have tried it in nearly every position and it still won't fire up! has anyone got any sugestions?

[huxley309 0]

running on the 8valve ignition with an adaptor.

 

I believe there's your problem, you'd probably need a mappable ecu to get the correct ignition advance

[yorkdave 1]

i have seen a bogg brothers conversion running nearly the same set up, a stadard mi on r1 carbs and it was makin 145 bhp at the wheels with 8valve ignition! i know it works, just have to figure it out.

[pug309twin40s 1]

sounds like the same problem i had on my 309 mi16 twin48 goodwood when i took the ht leads of and then put them bk on wrong..

 

 

usually the dizzy needs to be either pointing at an angle towards the front of the car of towards the rear to work.

 

 

definetely sounds like the dizzy is in the wrong position or the ht leads in the wrong order.

 

i'll take a pic tommorrow of how my dizzy sits.

[taffycrook 2]

Not sure why it happens but I have had ign amps break down after conversions.

Sometimes they work other times only fire two cyl or none at all after you finish cranking. So if you check the spark with the engine cranking it fires but when you release the starter it stops. Wierd but true.

 

I guess your issue is timing related. Get a timing light and set it up at 12 bdc degrees at tickover. that will get it going.

[simsk 1]

might sound stupid but the cams arent in the wrong way are they? my mate did this to my eight valve and was just blowing through the sad. He apparently knew what he was doing? just a thought.

[Fuqa 0]

ive had a similar problem. backfiring, popping , wouldnt fire.There was a small amount of contamination in the dizzy cap.. cleaned it , and it was perfect!

[ada205 2]

Hi mate.

 

Was just wondering if you're dizzy adapter is like mine and has two positions for dizzy bolts? If so, using the other hole's will give you more adjustment, though only in one direction. As i'm finding out to my cost, these things can be badly machined and out of alignment. To see what i mean, check out this thread i posted a few weeks back when my Mi killed another dizzy! http://forum.205gtidrivers.com/index.php?showtopic=58735 What Martin says is definately what killed my dizzy, and his advice seems to have cured the problem.

 

When it came to replacing the dizzy, i had similar problems to you, though was'nt as bad, certainly no back firing, but when i put the dizzy to central position, the car would start, but only just, so the adjusting began! With the dizzy fully retarded, the car was running better, but ticking over high, and still pinking, obviously advanced, but was already fully retarded! Then remembered seeing 2 holes for dizzy bolts on either side of adapter, pictured here-

Cant see in the pic, but theres obviously a matching pair of holes on the other side of the adapter.

 

When i changed the bolts around, i had loads more adjustment, though still nearly used up all ajustment to get the car to stop pinking. Was tempted to go and get another couple of holes machined into the adapter to give a liitle more scope for adjustment.

 

ps. The metal bits lying in the bottom of the adapter are the ramains of the previous dizzy!

Edited May 22, 2006 by ada205

[yorkdave 1]

thanks alot for the advice fellas, i'm trying again tomorrow nite as i'm waiting on some spark plug hole seals from pug. i reckon i might have the dizzy 180degrees out, it is pointing towards the rear of the car, so i think i might try it the other way. thanks alot for the help and i will let you know how i get on.

[ada205 2]

thanks alot for the advice fellas, i'm trying again tomorrow nite as i'm waiting on some spark plug hole seals from pug. i reckon i might have the dizzy 180degrees out, it is pointing towards the rear of the car, so i think i might try it the other way. thanks alot for the help and i will let you know how i get on.

Sorry to say mate, but dont think you can be 180 out on 205's. Sure someone will correct me if i'm wrong, but think the locating pins on the dizzy spindle are slightly off centre, making it impossible to be 180 out. Noticed this a while back and tried to fit 180 out when replacing mine recently just to see, and could'nt do it when i tried. Same obviously goes for the rotor arm, which only fits in one position. Dont know if this is true for all gti's, early and old alike, or if maybe the cap can be put on 180 out, but as long as the leads are coming of towards the the back, towards the bulkhead, then the caps the right way around anyway. A i say, someone will know on here and no doubt correct me if wrong.

Edited May 22, 2006 by ada205

[yorkdave 1]

i reckon you are probably right and i have never seen one with the dizzy facing the front of the car, but i reckon if you spin the dizzy housing whislst leaving the end located in the cam shaft you will be able to face it forwards. i'm going up to the car now so i will let you know how i get on.

[richors 0]

Nice to see you out in the car tonight mate and it really does look good.

Hopefully see you on track before long and have a safe trip to Germany.

cheers,

 

Mark.