dand39

So I read that h22a1 rods must be modified to accept Type S pistons b/c they use floating pins. I also read that h22a4 rods don't need to be altered at all.

So my question is: can I use my stock JDM h22a rods with Type-S pistons? If not, should take this opportunity to buy aftermarket rods or just buy a4 rods?

Thanks in advance.

92hondalude

i used a4 rods
i used them because i bought a h22a4 motor so that was the cheapest way to go

Under_Pressure

but a4 rods don't work on other h22a block's? don't they have larger journals???

I maybe wrong

LudeHatchH22a

Yeah whats up with this.
Is there some modification you can do to the jdm rods to make then fit the wrist pin?
The a4 rods dont fit a jdm block, do you need type S rods?? they are different too right?

JTCdudeman

machine shops can press off the wrist pins and put the floating wrist pins of the Type S pistons back in there for you... That simple...

vinuneuro

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Under_Pressure &raquo;</TD></TR><TR><TD CLASS="quote">but a4 rods don't work on other h22a block's? don't they have larger journals???

I maybe wrong</TD></TR></TABLE>

It's the crank journal that's different: 55mm vs. 50mm. The h22a4 that came in the 97 was still 50mm though.

The Birdman

1. You can modify h22a1 (or jdm equivalent) rods to work with the floating wrist pin design of the type s piston.

2. You can use h22a4 (or jdm equivalent) rods, in your h22a1/jdm equivalent block with type s pistons.

3. You can get aftermarket rods.

#2 is true because even though the main journals are 55mm instead of 50mm on the '98+ h22a4 blocks, the rod journals remained the same... aka it doesn't matter about the rods.

vinuneuro

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jd3jdm &raquo;</TD></TR><TR><TD CLASS="quote">1. You can modify h22a1 (or jdm equivalent) rods to work with the floating wrist pin design of the type s piston.

2. You can use h22a4 (or jdm equivalent) rods, in your h22a1/jdm equivalent block with type s pistons.

3. You can get aftermarket rods.

#2 is true because even though the main journals are 55mm instead of 50mm on the '98+ h22a4 blocks, the rod journals remained the same... aka it doesn't matter about the rods. </TD></TR></TABLE>

He said everything you need to know

Under_Pressure

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jd3jdm &raquo;</TD></TR><TR><TD CLASS="quote">1. You can modify h22a1 (or jdm equivalent) rods to work with the floating wrist pin design of the type s piston.

2. You can use h22a4 (or jdm equivalent) rods, in your h22a1/jdm equivalent block with type s pistons.

3. You can get aftermarket rods.

#2 is true because even though the main journals are 55mm instead of 50mm on the '98+ h22a4 blocks, the rod journals remained the same... aka it doesn't matter about the rods. </TD></TR></TABLE>

Thats good to know

now can u also modify h23 rods to work with type S pistons? and so what would be the compression ratio of a stock h22 head on a h23 with those pistons?? 93oct friendly????

JTCdudeman

Yes, you can 'modify' the h23a1 rods to accept the type S pistons... This is actually a very simple task... There are several people making h23vtec designs which you could search and see.. The type S is a little more rare because of the extra $$ involved and the higher compression.

There was a thread calculating out the h23vtec compression and even with type S pistons compression and there ended up being no conclusion because of specs being missing, misinformed, etc... The general overall census was above 12:1.. which is still 93 octane friendly as long as TUNED.

flyrod

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dand39 &raquo;</TD></TR><TR><TD CLASS="quote">can I use my stock JDM h22a rods with Type-S pistons?.</TD></TR></TABLE>

Yes. You have two choices: Take the rods to a machine shop and have bushings installed and fitted to the floating pins, or just use the rods as-is. The floating pins are smaller than the pressed pins, so if you just use the floating pins with the press fit rods the clearance is about right. This topic comes up about once a week (did you search?), and I've seen a few people post saying they just used the old rods without modification.

If you just want to get new rods, Eagle makes a rod with a smaller journal to fit the honda floating pin.

The Birdman

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Under_Pressure &raquo;</TD></TR><TR><TD CLASS="quote">now can u also modify h23 rods to work with type S pistons? and so what would be the compression ratio of a stock h22 head on a h23 with those pistons?? 93oct friendly????</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JTCdudeman &raquo;</TD></TR><TR><TD CLASS="quote">Yes, you can 'modify' the h23a1 rods to accept the type S pistons... This is actually a very simple task... There are several people making h23vtec designs which you could search and see.. The type S is a little more rare because of the extra $$ involved and the higher compression.

There was a thread calculating out the h23vtec compression and even with type S pistons compression and there ended up being no conclusion because of specs being missing, misinformed, etc... The general overall census was above 12:1.. which is still 93 octane friendly as long as TUNED. </TD></TR></TABLE>

As far as change in measurements, I can tell you what is going on, I just don't want to go dig up that compression calculator I had saved somewhere...

The head chamber cc's are changing from 50cc to 53.8cc and your compression height is changing from 1.203 to 1.221. (This is going from the h23 complete motor, to the h23 bottom end with type s pistons with an h22 head.)

Here is a thread to show you just how much **** went in to getting the numbers I have listed above.... https://honda-tech.com/zero...age=1

If you notice... one of the last estimates posted shows a 12.56:1 compression for an h23 vtec with type s pistons.

The closest thing I have seen to the truth is better stated here I believe....https://honda-tech.com/forums/showthread.php?t=599 which claims an 11.53:1 CR. I see that to be pretty accurate





Modified by jd3jdm at 8:21 PM 2/9/2006

tgh22a

here is a link that might help, no now really know for sure what the piston dome displacement is for the type s pistons though. https://honda-tech.com/zerothread?id=1505223