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Trying to problem solve 87 Shark

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Old Jun 6, 2013 | 11:28 AM
  #31  
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If it's sluggish down low and smooth up top, I'm still not convinced you are getting first gear. Have you tried putting the lever all they way into low... which is 2nd if rolling and 1st if stopped or less than X mph where x = 6mph +/- 3.

From a standstill, try first and slowly accelerate to say 20 mph, then switch focus to RPMS and run up to 5 k and report back your speed. I'd have to go check but it should be less than 50 mph. If not, I'm with Bill and the thought of 2nd gear starts.

"Rough down low and smooth up top" can also be leaky ignition wires. Back before I replaced mine, after letting it sit out in the rain it would run really rough down low and smooth out up top. Driving it hard like an itialian tune up followed by a break to let things dry, smoothed that out.

Indy is only 3 hours away. Bring it down and we can round up Han's and the shark tuner and iron this out. Can check your cam gear timing too. I don't mind supplying the beer. Sunday afternoon could work for me.
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Old Jun 6, 2013 | 03:23 PM
  #32  
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Thanks...I'll give this a try after work today....That's a great offer...Auzi

Thanks!
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Old Jun 8, 2013 | 12:35 AM
  #33  
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Auzi , I tried it on my way home from work today was around 40-45 mph around 4500rpm
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Old Jun 8, 2013 | 09:32 PM
  #34  
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Tkrtape12 hit me up I have a local guy that can help rguzman224@gmail.com
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Old Jun 8, 2013 | 10:16 PM
  #35  
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Did you experience the same sluggishness on the bottom end prior to the timing belt being replaced?
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Old Jun 8, 2013 | 11:11 PM
  #36  
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i cant offer any advise, but to comment... my '85 would launch slideways from a dead stop on dry pavement before my TB/WP change. now it wont, but I also put on 4 new treads (also changed rears from 7's to 8's) and a 4 wheel alignment. also has a vibration up to 45 mph, but smooths out at 50 and above. I had the timing rechecked, timing is spot on. also starts from 1st, not 2nd. So I am curious, as the symptoms are similar.
also to auzvision...I am in Terre Haute. didnt know anyone here was that close.
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Old Jun 9, 2013 | 01:29 AM
  #37  
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If the cam gears are changed, they can be "eyeballed" to within several degrees of their previous setting by making marks before the old gears are removed. And this assumes the old gears were timed correctly. When the cam gears are changed, the factory procedure for checking the cam timing requires removal of the cam covers and the use of a dial gauge. Almost no one does this during a timing belt/cam gear job. And very few mechanics would have Ken's inventive alternative tool for setting the cam gears. So, you can expect replacement cam gears are not going to be terribly close to correct. I found the timing in one 87 was off 7 degrees.

Also, 87s and 88s have 2.2 rear end ratio, and the acceleration off the line doesn't quite match the 89 2.54 rear end automatic.

Also, you mention some roughness at lower RPMs. Auzvision pointed out possible ignition issues. You say things are better with some fuel cleaner runs too. I may not recall all the tune up things you have done, but there may be a number of things still to do.
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