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mandalore4411

cam towers.

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this may be really obvious but i just wanted to know for sure.

ea82 camtowers(everything in um) and put them onto an ea82T. they seem the same to me i just wondered if the lobes might be different or something, or the ditsy.

 

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it is said the turbo cam is different, though i doubt you'd notice much difference if you needed to swap for a daily driver.

 

distributor is dependent more on years probably, would be best to keep matched to the vehicle as there are a few changes from 86, 87, 88.  pigtails can be swapped on some if that's the only difference.

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No valve overlap on turbo cam.

 

Mark

The valves are part of the cylinder head.  The cam is part of the camtower assembly.  The camtower cannot be different due to valve placement, because valves are not part of the camtower assembly.  I have interchanged my camtowers on my EA82T and camtowers off of a EA82, with no problems.

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Valve overlap is a term used to describe the duration when both the intake and exhaust valves are open at the same time. On most turbo engines, the valves are not open at the same time because the pressure on the exhaust side is greater than the intake side, or the boost pressure. On a N/A engine, the valves will be open at the same time for a short duration. This will cause the out going exhaust gases to help draw in the fuel/air charge. The total duration of valve overlap is determined by many factors, and one of those cam designer's secrets. I hope this helps. I too think it may not make a lot of difference for a daily driver.

 

Mark 

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IIRC, the 85 and 86 turbo cam profile differed little, if any, from the non-turbo.  The 87-up had alterations in the timing, duration and overlap, with a slightly decreased overlap as compared to the non-turbos.  In essence, the later turbo cam was a milder grind.  There is a thread floating around that lists the various cams.  I think that post was by Gloyale, and relatively recently.

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As has been said, the cam is different, but the tower is not.

 

However, if youre going to drop a turbo cam on a non turbo motor, id suggest you do it for both sides. The valve timing is different IIRC..

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