getting depressed now

[bens_cab]

Hi all im using msns-extra 029q2 v3 vw 20vt engine 150bhp

getting to the point of scrapping the idea of running megasquirt
got the conversion up an running will idle sweet now got lc1 wideband which is configured both mt and logworks read the same

it will idle ok as soon as i try and drive it will missfire pop and bang if under to much load havnt been able to get it above 3000rpm even on ligh load its not right

im using vb291s to fire the coil on plug packs they are 3 pin pack and seem to work ok

on the original car the engine came from the coils plugged into a output stage ignition controller should i have used this between the ms and the coils is that the problem im getting like a weak spark under load

im sure its a weak spark cos even at 13 to 14 afr the plug will soot up which means i then have to clean them before another run

id post my datalog and msq but the forum wont give me that option

helpppppppppppppppppppppp

[jsmcortina]

What dwell are you running? As long as the VB921 are cool, try increasing the dwell.

Are you running resistor plugs?

Do you get any tach spikes or resets?

James

[bens_cab]

hi james my dwell is

5.0 cranking
3.0 running

it seems to get really bad when i put a bit of load on the car if i drive it gently its not to bad but if i try to acceleratre in 4th it just bogs down pops and bangs

richer or leaner doesnt seem to make to many changes to the running it will sit and idle ok

i did notice my coolant temp spikes all over the place when warming up but once its warm it sits at 101.7 and doesnt move on the datalogs even though mt reads it going up and down with the fan

ive tried to different sets of plugs cant think of the top of my head what they are ill check

i dont think i get tach spikes when it start to miss behave i tried to post a datalog but the forum wont let me


Ben

[bens_cab]

my plugs are

bosch super r1.288 these are my new ones the old ones are

ngkbkur7et

if that means anything to u

[keithmac]

Coolant temps shouldn`t spike, could be showing up a wiring/ grounding fault that may also effects other parts of the system?

[screamer69]

heres one of his data logs

http://homepage.ntlworld.com/screamer69/ben/friday3.xls

[chrispel]

I think you need to fix your MAT and CTS. They don't look like there working correctly. I'm sure your intake manifold gets hotter air then 50 degrees or is this in C?

[Mk1rocco]

im using vb291s to fire the coil on plug packs they are 3 pin pack and seem to work ok

I'm certainly not expert at this sort of thing but that sentence stuck in my head in light of something I read ealier today in this thread

If you want to use the cop's without the added complexity of a second vr circuit, try this. First,check that your cop's only have two wires going to them. Three wires usually means that the driver is built in. If you have the two wire version, wire pairs in series for wasted spark, and drive them with the vb921's. This gives a hot enough spark to run a 2 liter subaru @ 20lbs of boost. If you are lucky and have the three wire cop's, them you don't even need the vb921's. You can drive them from the led's

[bens_cab]

vw did 2 types 3pin non amplified and 4 pin amplified i have the 3 pin the vb921s supply an amplified current i beleive

[Mk1rocco]

I didn't know that. Just curious though, one wire's obviously power, another gets grounded through the vb921, what does the 3rd wire do?

[bens_cab]

on the 3 pin packs

1=12v swicthed via fuel pump relay to all 4 packs
2=earth to all 4 packs
3=triggered earth from ms

the forth wire is an earth i think not to bothered as i only have 3