Weak top end power
#1
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Weak top end power
Ok my 85 gsl
Stripped and rebuilt nikki w/mech secondaries
Intake has the shutter valve removed.
Stripped of all emissions/rat nest
Direct fire ignition/Ngk plugs
Factory exhaust with no cats and a free flowing muffler. (Need header yet)
Car seems to pull nice in lower rpms. Seems weak in the higher r's. I can pull to 60 ok but it seems like after that it doesn't pull as hard as it should? And doesn't get over 100 for crap. Maybe I need bigger carb jets? Just before it was parked for winter the msd box took a **** so I just parked it for winter. Put new box in now and runs perfect but just seems slower than last summer. I don't know if that has anything to do with it?
Stripped and rebuilt nikki w/mech secondaries
Intake has the shutter valve removed.
Stripped of all emissions/rat nest
Direct fire ignition/Ngk plugs
Factory exhaust with no cats and a free flowing muffler. (Need header yet)
Car seems to pull nice in lower rpms. Seems weak in the higher r's. I can pull to 60 ok but it seems like after that it doesn't pull as hard as it should? And doesn't get over 100 for crap. Maybe I need bigger carb jets? Just before it was parked for winter the msd box took a **** so I just parked it for winter. Put new box in now and runs perfect but just seems slower than last summer. I don't know if that has anything to do with it?
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I'm curious about the answer to this also. I'm running pretty much the same setup on my 83 GSL (with RB streetport exhaust and half bridge engine) Nikki is maxed out in terms of venturi size and jets. I noticed a drop in power when I went direct fire and she struggled to climb past 6500 rpm. Without the know how or ability to check the MSD 6A box, I opted to go back to the factory ignition. There's some improvement , but not enough. Even advanced the timing to 20 deg and she feels and idles better, but not as powerful as she did before the mods.
I'm looking around for a 48 IDA Weber and 4 port manifold to see if it makes a big difference.
I'm looking around for a 48 IDA Weber and 4 port manifold to see if it makes a big difference.
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Yup new filter last week. Something just isn't right. It seemed like it was starving for fuel up top sometimes but when I ran my dfi coils in series vs parallel it didn't do it anymore. So I'm thinking ignition issues? Maybe this box sucks? I figured they either work or don't? Can they be week?
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Yup new filter last week. Something just isn't right. It seemed like it was starving for fuel up top sometimes but when I ran my dfi coils in series vs parallel it didn't do it anymore. So I'm thinking ignition issues? Maybe this box sucks? I figured they either work or don't? Can they be week?
you might try running the coils directly from the alternator instead of the normal source, as 14v will be more powerful than 12v
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One thing I noticed also in the dizzy. I had the cap of running it with the dfi and when I rev it the trailing vacuum advance really seemed to move a lot but the leading barely moved. Is that normal?
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I have the msd hot wire straight to the battery. I could try to go off alternator. Last summer the dfi was really noticeable. Now with the new box it isn't.
One thing I noticed also in the dizzy. I had the cap of running it with the dfi and when I rev it the trailing vacuum advance really seemed to move a lot but the leading barely moved. Is that normal?
One thing I noticed also in the dizzy. I had the cap of running it with the dfi and when I rev it the trailing vacuum advance really seemed to move a lot but the leading barely moved. Is that normal?
they have it setup so it runs a 15 degree timing split at idle, and WOT, but at cruise its more like 5.
oh if you have an MSD, its probably fuel
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