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Difference in Engines Between 91 si and 91 dx?

Discussion in 'Engine Building' started by LudeBoy, Mar 8, 2004.

  1. LudeBoy

    LudeBoy Slave to the EF

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    Hi guys, just wondering if any parts besides the mpfi swap are interchangeable? Is the Cylinder head any different? Different Cams? Is the bore/stroke the same?

    Thanks in advance for any advise or opinions...
     
  2. Slammed90Lude

    Slammed90Lude Senior Member

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    simple answer.....yes- the heads and cams are interchangable, obviously the manifolds are interchangable- the bore for both the motors is 75mm, while the stroke for the Si motor (d16a6) is 5.5mm larger at 90 compared to 84.5
    i think the longer stroke might result in valve to piston clearence issues supposing you swapped the Dx (d15b2) head onto the si block- just a guess though- But there is really no reason to swap d16a6 parts onto that block- if you have both motors use the A6 since it's power and torque are 108 and 100 respectively, while the d15b2 makes 92hp and 89 ft/lb of torque

    hope that helps- you can check the reference section if you need to see more specs or need more help

    http://www.hondaswap.com/forums/index.php?showtopic=29825
     
  3. LudeBoy

    LudeBoy Slave to the EF

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    Thanks for the info. Do you think I would benefit from just a cam swap? I am thinking that the weakest link is probably the intake... Do you know if the 16a head outflows the 15b? I have built a domestic car but I am pretty new to the world of imports. I dont have the money time or tools to do a swap so I was just wondering what kind of small mods I can do to pick up a few ponies. I already have a full exhaust (Header, cat elim pipe, cat back) and an intake. I bought a set of adj. coil overs and a set of Tokico shocks along with some 16's for the suspension. I also got both upper and lower front/rear strut braces. This is on a 91 dx hatch. I know I cant build a race car out of this (with the currnet engine) just looking to make it a sport daily driver.

    Oh yeah PARTS are cheap as hell for this car!!!!!
     
  4. Jeef

    Jeef NO MA'AM Moderator VIP

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    The heads are the same. Just swap in the si cam and do a mpfi conversion.
     
  5. erebunicrx

    erebunicrx my name is Dale

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    while its apart just buy a new cam . 200- 250 will get you a better cam. there is not that big of a difference between the cams and the heads are identical
     
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