what's the difference between the d16y5(hx engine) and the d16y8(ex engine)??? from what i can tell the exhaust manifold is different and the cam is(hx is more set for fuel economy), but what else besides that? or can i swap the ex cam over into the hx engine? i know the ecu is diff too.

thanks. Paul

 

...the VTEC lobe on the hx is actually "bigger"

Plus, the Hx head has roller rockers!

I am not sure if the Ex cam would work..but it may be worth a try.

A good Hx setup would be....ex intake mani and TB, good header, ex tranny....

If you switch ecus...you will have to rewire the primary o2 sensor on the hx.


[Modified by HXMan, 11:07 AM 9/15/2002]

 

NOTE: The EX cam uses three (3) intake lobes. Just like all the other VTEC engines. However, the HX is not a VTEC engine, it is a VTEC-E engine. Which uses only two (2) intake lobes. What the E stands for is efficiency. It is more efficient to (lighter as well) to just have two lobes, one larger than the other and to just have them lock together and follow the larger lobe. Just like VTEC only withouth the weight of another lobe and rocker arm. Let alone the four of them needed per cam. The 2001+ EX uses VTEC-E just like the 96-00 HX and 01+ HX.

The smaller 1.6L and 1.7L engines benefit from not having to turn the extra weight.

I wrote a thread a while ago on the specs of the HX vs EX cam. While it is documented that the HX cam has a higher lift on both the intake (.2mm)and the exhaust (.8mm) the duration is unknown. The only thing you do know is that the HX cam has a higher lift value.

Here is a picture of the roller rockers.



[Modified by Spade, 7:09 AM 9/16/2002]

 

Although reasonable speculation would suggest the Y8 cam has a much longer duration than the Y5 to take advantage of the multiple cam profiles

 

I would think so as well.....plus, we don't know if the rocker ratio is the same.

The EX has a 1.6:1 on the intake and a 1.8:1 on the exhaust......does the HX have the same? I don't know and I traded it in before I found out. I do know that those roller rockers are a very smooth when it comes to friction on the valvetrain though.....just listening to it with the valve cover off right next to my EX was a WORLD of difference.

 

These roller rockers, can they be used in another engine, like a y8 or y7 valvetrain?

 

spade i got a question for ya bro, would the HX run fine on an EX ecu? ii'm trying to run an uberdata setup but the only basemap i can find is the d16y8...

-kenny

 

i want to know whats the difference from the hx tranny and the ex tranny?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Quad-Damge &raquo;</TD></TR><TR><TD CLASS="quote">i want to know whats the difference from the hx tranny and the ex tranny?</TD></TR></TABLE>

ex has shorter gears