Not sure if this is true or not, but someone said that the automatic JDM/USDM motors have less aggressive cams than the 5 speed ones. Is this true? And if it is, how can you tell if a Long block came originally automatic or 5 speed without having the tranny?

 

does it have a flywheel or a flexplate on the crank?

 

No it is not true as far as JDM. I made 175 hp on an auto longblock as well as a 5 spd longblock, with the same mods one each on a stock p13.
I even measured cam lobes later, I could not tell 5th gen USDM cams from 4th gen JDM auto cams, or 4th gen jdm 5 spd cams based on lobe heights.

Now I DO believe the USDM auto is detuned SLIGHTLY at the ecu, but the cams are the same.

 

Not to mention the slightly higher drivetrain loss through the automatic transmission, I can see where people might think the auto's have less aggressive cams. All H22's are internally the same.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Finest &raquo;</TD></TR><TR><TD CLASS="quote">All H22's are internally the same. </TD></TR></TABLE>

I don't think so. In some years the auto engines had slightly better cams, supposedly to help make up for the additional drive train loss. I'm pretty sure this is all in the FAQ...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by flyrod &raquo;</TD></TR><TR><TD CLASS="quote">

I don't think so. In some years the auto engines had slightly better cams, supposedly to help make up for the additional drive train loss. I'm pretty sure this is all in the FAQ...
</TD></TR></TABLE>

Enough that it would make a difference?

 

So whether or not I buy a 5-spd or an automatic long block, there won't be much difference? And even if I bought an auto one it could possibly be better right?

I was scared of buying an automatic long block thinking it was gonna be less as powerful as a 5-spd one. Ironically, it could possibly be better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by flyrod &raquo;</TD></TR><TR><TD CLASS="quote">

I don't think so. In some years the auto engines had slightly better cams, supposedly to help make up for the additional drive train loss. I'm pretty sure this is all in the FAQ...
</TD></TR></TABLE>

Link? I'm not seeing it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by flyrod &raquo;</TD></TR><TR><TD CLASS="quote">

I don't think so. In some years the auto engines had slightly better cams, supposedly to help make up for the additional drive train loss. I'm pretty sure this is all in the FAQ...
</TD></TR></TABLE>

The engines you are referring to are the SH engine. The helms spec's larger mid-lobe lift.

 

So if it's a 95 and older than I'm fine regardless of what motor I select...correct?

 

I wouldnt worry, I bought a longblock that was an obd1 auto, did my swap, so far as I know its the fastest n/a prelude in colorado lol. and with the jdm h22, i/h/e it has run 15.8 at our altitude, where the best usdm I know of is 16.7! thats 4th gens, both 93 model even. Also seen a 5th gen with i/h/e run 16.2, usdm motor.

 

obd cams are smaller and the 5 speed ones.

i also had to cut off the dowel on the crank so it would work with my oem flywheel

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by alterdcreations &raquo;</TD></TR><TR><TD CLASS="quote">obd cams are smaller and the 5 speed ones.

i also had to cut off the dowel on the crank so it would work with my oem flywheel</TD></TR></TABLE>

OBD what?

 

2..

 

USDM OBD2 5 speed cams and OBD2 auto cams are the same part number.

 

if i was to pick up a motor, i would pick one up that was an auto because it doesn't take a beating like the manual ones do and theres no chance of people miss shifting and over revving the motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by v4lu3s &raquo;</TD></TR><TR><TD CLASS="quote">USDM OBD2 5 speed cams and OBD2 auto cams are the same part number.</TD></TR></TABLE>
maybe so but according to the service manuel they have different lift and duration.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by alterdcreations &raquo;</TD></TR><TR><TD CLASS="quote">

maybe so but according to the service manuel they have different lift and duration.</TD></TR></TABLE>

the service manual also says the type-sh cams are different, but the dealer does not have a different part number for them either. Any US dealer that has cams is going to give you the same cam for a 5th gen prelude no matter what transmission is bolted to the block,