Does anyone know if there is a difference? Are they both the same? Or does the JDM H22A once have a higher lift/longer duration?

I just recently upgraded the valve-train on my H22-Civic. Now I have a set of JDM cams laying around. I was wondering if I should throw them into my Prelude's USDM H22A1?

Thanks!

 

I think they are the same. The JDM H22 just has a higher compression. Now the SH cams are different than the base model cams, and the JDM Type-s cams are also.

The only thing i can think of is to take both sets to a machine shop and measure both sets. Its the only way to make sure if they are different or the same.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Fly1865 &raquo;</TD></TR><TR><TD CLASS="quote">I think they are the same. The JDM H22 just has a higher compression. Now the SH cams are different than the base model cams, and the JDM Type-s cams are also.

The only thing i can think of is to take both sets to a machine shop and measure both sets. Its the only way to make sure if they are different or the same.</TD></TR></TABLE>

How many times do I have to type......SH CAMS ARE THE SAME AS BASE CAMS..Look it up fellas..Same part number.. The same cams, no differance.. Look it up, same part number..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Fly1865 &raquo;</TD></TR><TR><TD CLASS="quote">
The only thing i can think of is to take both sets to a machine shop and measure both sets. Its the only way to make sure if they are different or the same.</TD></TR></TABLE>

You know what, you got a point there, but I would hate to take out the cams only to find out that they're the same! That would suck.

 

Helms 97-99

Except M/T with active torque transfer (ATTS) BASE

Intake Exhaust
Primary 34.041mm 33.745mm
(1.3402in) (1.3285in)

MID 36.856mm 36.323mm
(1.4510in) (1.4300in)

Secondary 34.971mm 34.683mm
(1.3768in) (1.3655in)

M/T with ATTS SH

Intake Exhaust

Primary 34.041mm 33.745mm
(1.3402in) (1.3285in)

MID 37.229mm 36.704mm
(1.4657in) (1.4450in)

Secondary 34.971mm 34.683mm
(1.3768in) (1.3655in)

So if they are the same why are the SH cams taller than the BASE one.

 

The cams in a JDM H22 have more lift and duration than the USDM H22.

Whether it's the SH model or the base model because it's the same engine.

Now, the JDM H22 has higher compression, more aggressive cams and lighter valve train than the USDM H22. There are other differences between the two motors as well but I can't remember off the top of my head. Don't think that the 20 HP difference between the two motors is just due to higher compression because the difference between 10/1 and 11/1 compression will not yield 20 HP.

It will yield more like 10 HP, and (CBR) throw those cams in as soon as possible.

And fly1865, I think you are reading your Helms manual wrong, because the lift in my b16 intake cam is 10.2 mm. If you can get me a set of those 34mm cams get me a set as soon as possible. lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SiRWanabe &raquo;</TD></TR><TR><TD CLASS="quote">
The cams in a JDM H22 have more lift and duration than the USDM H22.</TD></TR></TABLE>

yup

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Now, the JDM H22 has higher compression, more aggressive cams and lighter valve train than the USDM H22.</TD></TR></TABLE>

never heard that valvetrain part, where did you get that?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">There are other differences between the two motors as well but I can't remember off the top of my head. Don't think that the 20 HP difference between the two motors is just due to higher compression because the difference between 10/1 and 11/1 compression will not yield 20 HP.</TD></TR></TABLE>

The only difference I'm aware of are the following:

1) more aggressive cams
2) 10.6:1 compression vs. 10:1 for the USDM
3) better exhaust manifold, more like a true header
4) more aggressive maps in the ECU

thats it, and it all adds up to ~10 more hp

IMO unless someone just gives you a set of jdm h22a cams for free, they arent worth buying

It will yield more like 10 HP, and (CBR) throw those cams in as soon as possible.[/QUOTE]

 

[Quote]
never heard that valvetrain part, where did you get that? [Quote]


http://www.h22a.org/specifications.htm.

About the lighter valve train, i was thinking about the b18c5, my bad.

[Quote]
The only difference I'm aware of are the following: [Quote]

1) more aggressive cams
2) 10.6:1 compression vs. 10:1 for the USDM
3) better exhaust manifold, more like a true header
4) more aggressive maps in the ECU


The 93 -97 JDM H22 has 10.6 CR, but the 97 and up JDM H22 has 11.1 CR according to the link above.

 

Well if i'm reading it wrong i guess i can't read


The JDM H22Aa have 10.6:1 compression the only H22A with stock 11:1 is the Type-S motor.

 

i was going to say:

Camshaft Lobe Height

Prelude (base)
Intake: Primary 1.3402 in.
Mid 1.4510 in.
econdary: 1.3768 in.
Exhaust: Primary 1.3285 in.
Mid 1.4300 in.
Secondary 1.3655 in.

Camshaft Lobe Height
Prelude Type SH
Intake: Primary 1.3402 in.
Mid 1.4657 in.
Secondary: 1.3768 in.
Exhaust: Primary 1.3285 in.
Mid 1.4450 in.
Secondary 1.3655 in.

The only difference between the base and SH is the VTEC lobes, and not by much

 

for those measurements, they have to be measuring the whole damn lobe, top to bottom. Well the diameter of the lobe anyway.

Mike