View single post by Esprit2
 Posted: 05-26-2009 08:31 pm
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Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 289
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Judson Manning wrote: (Snip)... The data out there suggests the dual 104 cam combo on 104MOP sprockets produces extremely 'peaky' results (http://www.lotusbits.com) with not much usable power in the everyday driving range.  One could argue shifting to 115/115 timing would produce more low-end torque and drivability.   Get a set of 104MOP sprockets, then find us a dyno shop and let us know!
Judson,

It's a big leap from minimal available data to a firm statement that 104 cams on 104 MOPs produce extremely 'peaky' results.   It's true, the power curve isn't as broad, or as strong below 3500 rpm as it is with a pair of 107 cams,  but a pair of 104's is not "extremely peaky".   They start to take off around 3500 rpm,  pull like a train from 4000 rpm on up,  and eagerly blow right past redline if you let them.   I know,  I do have a pair of 104's/ pair of DHLA45's/ 37 chokes on an otherwise stock Federal 907.   It doesn't even have the advantage of a desireable higher compression ratio.   It's not a trial to drive on the street,  but it does offer much improved top-end.

It's not 'cammy',  it idles smoothly,  and if you lug it down it will pull away smoothly under throttle without complaint.   Granted, you need to shift down if you want it to pull away smartly from "down low",  but it's not like driving a cammy "full race" hotrod small block that won't idle.

I know from experience.   I installed the 104's in 1995 and used the car to commute to work in congested metro traffic and it was never a problem.

I don't suggest 2 x 104's on 104 MOP's for anyone in search of a mild mannered gentleman's cruiser... use the 107's.   But it does bother me when folk who haven't lived with the 104's talk in all or nothing terms about how bad they are.   They aren't bad in traffic,  and what they offer to the more spirited driver on the open road can't be touched by 107's.   What does the owner want?

I also have a pair of DS2 cams on a 2.2 converted 907 hotrod.   They're hotter than the 104's,  but still trundle through traffic without complaint.

Last edited on 05-26-2009 08:57 pm by Esprit2