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Slugish @ 15-20Deg Timing

domo88

By domo88,
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domo88 Rookie

domo88

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In the process of tuning rb20det to standard specs. car is very slugish on standard base ignition timing also has been converted from auto to manual running standard auto ecu.

car has following mods

-unopened rb20det

-rb25 turbo

-walbro 255 pump

-pod with custom box and air duct

-12psi

-fmic

-3" exhaust no cat strait to rear muffler

-yellow jacket coil packs

-new iridium plugs gapped down to .8 from 1.1

i put the timing to the auto's 20 deg btdc with aac unplugged and idle @700rpm like this you put your foot down and it makes alot of noise but isn't pulling very well compared to if its on 30 deg btdc which it really gets up and goes (with no pinging). 20 deg, kick cluch in second will bog! 30 deg kick in second lets loose and abit of third? do i have to maybe gap the plugs back to 1.1 to bring ignition back to 20???

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Moodles2 Grand Master

Moodles2

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Posted

I assume your using the wire loop at the rear of the engine? Cheap timing lights tend to read double or half while using it.. i can't remember. Best place to get a timing signal is from coil #1

blind_elk Grand Master

blind_elk

Posted
Posted

I assume your using the wire loop at the rear of the engine? Cheap timing lights tend to read double or half while using it.. i can't remember.

DOUBLE. So you probably only have 10 BTDC.

Most accurate is to insert a spark plug lead between #1 coil and #1 plug, and time it "old school".

You are running good coils and fairly stock power, so I would suggest you open the gap back out to around 1mm.

domo88 Rookie

domo88

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timing was done with ignition lead between coil 1 and plug. also just moved it to 25 and i can live with thepower it has there but any thing under and its really boggy till your up around 6000rpm. This is all assuming the orange mark is 0 and 7th mark is 30 btdc?

Edited by domo88
domo88 Rookie

domo88

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my thought is if i make the spark gap bigger it will ignite the fuel quicker therefore i can make it fire closer to tdc (more retard) at the moment the spark is weaker and to ignite the fuel properly its having to fire that much more early or advaced. does this sound right?

domo88 Rookie

domo88

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no worries well its running well where it is and not pinging so i'll leve it there till i get money for nistune and get it on dyno. also when i had the timing backed off it was super fuely and poping when going down gears wich is nothing different when running rich but when i was pushing the accelerator and was running slugish and bogging down at 6000rpm it hit fuel cut??? my theory is that because it was running so rich the computer tryed to compensate for it by trying to correct a/f mixture with more air and maxed out the afm making it hit fuel cut??? this is possible? coz hasn't done it since got it running right... cheers for replys

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