1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

No Low End Power 12a

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Old Nov 20, 2010 | 10:12 AM
  #1  
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No Low End Power 12a

I recently swapped the engine out of my 84 GSL into a 83 GS. Got it finished last night turned the key it started 1st try. Its Idling at 700 wich is good, it will go up in rpm's all the way to redline but when im driving it seems to have no low end power.

Im assuming the problem is being cause by The wiring from the previous owner in the car was quite butchered he tried to rewire the distributor igniter plugs for some reason. How he had it was one of the igniters (the one on the right side) has a Black wire with white stripes on it going to both connectors.. and the other igniter has the stock plug but the black and white wire going to it has been spliced on.
So i took that part of the wiring harness off of my 85 and wired it in but my main problem is my 84 has 3 black and white wires hat go to the igniters while the 83's harness im wiring into only has 1 black and white wire so i just split the one to go to all the other 3.

Also i dont have any exhaust on it just header because were getting the new exhaust welded to fit today. So if thats my problem ill be quite relieved.

Also i had it running 2nd gen direct fire on my other car and havent installed it yet so how i have the plugs and wires hooked up are
t1 t2
l1 l2 i dont know if that will affect the power.. But im assumin its hooked in right

Thanks in advance guys
Ooh heres the picture of my wiring harness splice job.... if it helps
Attached Thumbnails No Low End Power 12a-img_1734.jpg  
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Old Nov 20, 2010 | 10:39 AM
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Whenever I did my swap to a weber carb and intake with a racing beat header I drove around 3 days before my exhaust got built. Was sluggish on the bottom end but pulled hard after 4 or 5k rpms. Once I got my exhaust done I had a lot better low end torque because of the backpressure. I'm guessing no exhaust on ur car is creating or at least helping your low rpm power
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Old Nov 20, 2010 | 10:40 AM
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I've had a header reduce low end torque slightly on a 13B, compared to an exhaust manifold.
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Old Nov 20, 2010 | 10:41 AM
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Hurting... not helping your low rpm power. Sorry for the typo
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Old Nov 20, 2010 | 07:05 PM
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Double check the plug wire routing. There should be markings on the cap (L1, L2, T1, T2) and the wires plugged into those locations should go to their respectively marked locations on the engine.

If that is all correct, then I would make sure that you are actually getting spark at the plugs.

Next step would be to verify the ignition timing.

Then, start checking for vacuum leaks.

Best of luck...




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Old Nov 20, 2010 | 07:44 PM
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Originally Posted by DarkDrakeX
I recently swapped the engine out of my 84 GSL into a 83 GS. Got it finished last night turned the key it started 1st try. Its Idling at 700 wich is good, it will go up in rpm's all the way to redline but when im driving it seems to have no low end power.

Im assuming the problem is being cause by The wiring from the previous owner in the car was quite butchered he tried to rewire the distributor igniter plugs for some reason. How he had it was one of the igniters (the one on the right side) has a Black wire with white stripes on it going to both connectors.. and the other igniter has the stock plug but the black and white wire going to it has been spliced on.
So i took that part of the wiring harness off of my 85 and wired it in but my main problem is my 84 has 3 black and white wires hat go to the igniters while the 83's harness im wiring into only has 1 black and white wire so i just split the one to go to all the other 3.

Also i dont have any exhaust on it just header because were getting the new exhaust welded to fit today. So if thats my problem ill be quite relieved.

Also i had it running 2nd gen direct fire on my other car and havent installed it yet so how i have the plugs and wires hooked up are
t1 t2
l1 l2 i dont know if that will affect the power.. But im assumin its hooked in right

Thanks in advance guys
Ooh heres the picture of my wiring harness splice job.... if it helps
Id solder and shrink wrap that wiring if I were you.
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Old Nov 20, 2010 | 09:06 PM
  #7  
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From: California
im getting spark at the terminals and i dont have a vaccum leak cuz its idiling where it used to. When i got the exhaust hooked up today it seems to have picked its low end back up so im assuming it needs a little back pressure to keep its low rpm power. And the reason i havent soldered and heat shrunk the wire is because i was not sure its 100% correct due to the fact it was running poorly. I plan on soldeirng and heat shirnking it within a day or so.

Does ne1 kno if that is correct either wayy?? im pretty sure it is but its nice to have some reassurance.
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Old Nov 21, 2010 | 01:53 AM
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From: Grand Rapids Michigan
Since you have suspicious wiring associated with the ignitors, there's one more check I'd make to be certain that it is functioning correctly. Unplug one of the ignitors (say leading) and then see which plugs are getting spark. If you unplugged the leading, then you should have no spark on leading but still have spark on trailing. Then, perform the same test with the other ignitor.

If all seems okay after that test, then you can probably assume that the cobbled up wiring is at least performing correctly.
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Old Nov 21, 2010 | 09:47 AM
  #9  
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which igniter is leading and wich one is trailing?
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Old Nov 21, 2010 | 10:34 AM
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I just wired up my ignition and it was pretty simple if you want to check it to make sure what's there is wired right.

The positive side of both coils gets key switched 12V utilizing the larger wire on your stock harness and then goes to both the plugs on the distributor. If you look at each plug it is the vertical part of the T. They are all spliced together one way or another in your stock harness.

The horizontal part of each plug connects to the negative symbol on your coils... Those have to run seperatly from each other. The ignitor furtherest away from the pots (or towards the front of the car) is leading. Follow that wire back to whichever coil it goes to and make sure that the spark plug wire goes to L on the cap.
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Old Nov 21, 2010 | 12:17 PM
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Originally Posted by DarkDrakeX
which igniter is leading and wich one is trailing?
i just pull the cap off and look. the vac pod workings have L and T stamped on them of which ever ignitor pickup is mounted to.
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Old Nov 21, 2010 | 07:51 PM
  #12  
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ok well i checked it earlier and i have it wired up correctly. The forward igniter is controlling the leading and the back mose one is controling the trailing. Thanks for all the help guys. Another one of my problems was the gas in the car was bad.. It would bog horribly under high rpms i drained the gas tank and filled it up and its running great thanks for all the help guys.
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