Weak Spark

[haubstr]

Trying to get the L20b in my fathers truck running good but can't seem to get a good spark...

This is my Dad's Truck...

We have all brand new ignition components(plugs, plug wires, cap, rotor) on an electronic black box distributor/EI coil... Remember this is a Turbo L20B, bored 40 over, low compression pistons, A87 open chamber head, running on a stock Weber 32/36...

When we checked the spark all we could get is an orange spark... plugs are gapped to .040 (to much gap?)

When we first fire it after cleaning the black spark plugs it will start and after about a minute or 2 it will start overloading from gas and then it will die... by then spark plugs are black and need to be cleaned again...

 

I'm going to try taking my Pertronix distributor/EI coil/MSD 6A box and put it in the truck to see if that will help the boost the spark...

 

I'm going up to his house next week to try some new things to get it running right... Any ideas are greatly appreciated...

 

Thanks in advance

 

Jamie

'Haubstr'

[jefe de jefes]

Are you still running through the ballast resistor?

[metalmonkey47]

Check wiring. Maybe a bad connection somewhere?

 

 

 

If you used crimp connectors anywhere, remove them and solder (like a bawse!)

[haubstr]

No... no ballast resistor...

 

Ya... I'll have to go back through all the connections... I think most are crimp connectors

[banzai510(hainz)]

I swear a replied to this thread already and it dissappeard?

 

ck the valve lash

 

also ck to make sure the HOT start wire is connected to the + side coil.

 

where the ballast resisitor was make a jumper and that wire should go toe a female connector with 2 wires in it.

 

so the blk/white wire goes thru the jumper then routes to the + side coil which I think is blk/red.

 

Hopefully this will solve it when its cold starting

[banzai510(hainz)]

wondering if turbos need to be jetted different?

PM Betvorgen on the 510realm as he has a Weber DGV but a blow thru.

 

timming and retard with turbos????????

[Mini-L320]

Deffinately go with an MSD Box, plus Retard Timing also cause your running a Turbo.

Gotta remember if ur running a bigger Carb then that means more fuel meaning u need more Spark to burn it off.

[haubstr]

Just wanted to everyone know what happened with the truck... We changed the spark plugs to the BP6ES and gapped them to 28 from 40 and it fired right up and after about 10-20 seconds of warming up, the thing idled... there still a little hesitation when you hit the gas pedal hard and there is a little smoke coming out the exhaust but I think it just needs to be fine tuned now...

 

I saw advice of retarding the timing? How much?

 

Thanks again for the advice...

[datzenmike]

For idle and anything less than boost conditions a stock setting of 12 degrees is fine, after all it's a stock L20B most of the time. In fact with low cmpression you may be able to advance it slightly for best starting a running power and economy.

 

Under boost conditions all bets are off. The more fuel and air crammed in by the turbo the less time needed to burn it so the timing needs to be retarded. The best thing is an adjustible retard system that retards by boost pressure. On top of this, higher boost compression means more heat consentrated and the risk of detonation. (ping)