RHD_BB4T

What's up, guys?!

Two topics that I hear being thrown around lately are H-Series=FRM and discussions between open and closed decks between the various H-Series engines.

1) What does FRM stand for? I understand that it's the material or mfg process of certain H-Series OEM sleeves. I've also seen horror pix of blocks that were not re-sleeved before installing forged pistons. But what causes this?

2) What's the difference in a open-deck vs. a closed-deck engine? Maybe I know the term, but I just can't associate it with any particular terminology.

Thanks for the time and bandwidth, everyone! And please excuse me if these questions sound mundane and repetetive!

Dan P.-

RHD_BB4T

No help, huh? OK, can someone please help DIRECT me to where I can find the answers to these questions?! TIA

Dan P.-

aeolus

FRM stands for fiber reinforced metal.A open deck would look similar to how a stock b series block looks without the head.A closed deck does not have a water jacket opening at the top,therefore the term called"closed deck".

Boostless97Lude

hey smart ***, you see that thing up the the top right that says "search"?? next time you wanna get smart, try searching first.... i think we have talked about FRM about 52 times in the last year (notice the 52, as is, ONCE A ******* WEEK)

GZERO

seriously, search, but here https://honda-tech.com/zerothread?id=351811

we all make mistakes

BoostedH23a1

OPEN deck


Closed deck

JDM BB2

Those are pictures of two open deck blocks. The second block you have labeled as "Closed Deck" just has a block gaurd ... Here is a picture of a closed deck.


JDM H22a block sleeved by Golden Eagle ... closed deck

bare jdm h22a block.

The 93-96 H22a1's (and the jdm h22a's) are closed deck
The 97+ H22a4's are open deck.

-Mike

sslude

whats the difference in performace? so the water pump pumps water to where the space is?

RHD_BB4T

Boosted97Lude,

If I would have asked "Please be a ******** by wasting mine and everyone elses time by making pointless bullshit remarks!" Then you would certainly have been the first one I and everyone else here would have congratulated for your innovative and insightful gestures and remarks! You are precisely the reason 95% of tech and performance boards are useless and pointless. The next time that you DON'T know something, or the next time you DON'T want to share your, obviously far superior and technical intellect compared to the rest of us, just feel free to shut the hell up!

Some of us haven't BEEN here for the past 52 weeks, so you can't expect everyone else to know what the hell YOU have been doing in that time.

It's funny, the amount of space and time that people want to waist just TELLING you that they don't want to help you! And, in turn, mine for having to sit here and justify a question every time I feel compelled to do so!

To the rest of you, thanks so much for your help and patience with those of us not so fortunate to have been born WITHOUT a Helm's/Honda manual and performance dictionary implanted in our heads! And again, sorry for having to waste those of you who WANT to help's time with having to waste mine with people like the all-knowing "Boosted97Lude!"

Dan P.-


[Modified by 92_BB4, 8:20 AM 2/24/2003]

Boostless97Lude

actually ********, i probaly know more about Preludes than 90% of this board, and yes, that include the engine

my point was simply, USE THE ******* SEARCH FUNCTION

and i wasn't wasting anyones time, you are wasting peoples time by asking a question that has been ansered time and time again

and yes bitch, i am all knowing

lildrgn2.0

But you were a smart *** with this post. Next time just say "anyone?"

Your statement is that of a smart ***...
So Boosted replied (be thankful it was not todd, cause he would have just locked your post and removed some points)

search
v. searched, search·ing, search·es
v. tr.
To make a thorough examination of; look over carefully in order to find something; explore.
To make a careful examination or investigation of; probe: search one's conscience for the right solution to the problem.
Law. To make a thorough check of (a legal document); scrutinize: search a title.

To examine in order to find something lost or concealed.
To examine the person or personal effects of in order to find something lost or concealed.
To come to know; learn.


AKA.. little link on the top right hand side of the page.
at this point it would be easier to say.. "sorry, I should have used the search function" followed by. "Thank you for the help"
rather than to get into a flame war with senior members.

Thank you, have a nice day!

Finest

I don't think you're a smart-a$$, or it was a smart a$$ remark...but you're just new to this stuff. Be courteous and you'll get your answer soon enough.

But, given the fact that this was posted only 3 hours since your first...not everyone will have a chance to read this and tell you. I wait at LEAST a day before I bump it back up...

BTW, I must be that other 10%.

BoostedH23a1

i know that one is open deck. but thats what a closed deck looks like essentially. didnt have a pic of my block though.

ejectseat

sslude - there's no difference in performance. However, when considering forced induction, a closed deck is far more stable under boost, as the cylinder sleeves are reinforced at the top and bottom.

optikal_blitz

i just read a post about FRM and open/closed deck issues.. i was wondering this myself and i actually havent seen it discussed here. maybe i wasn't paying much attention though anyway, i think everyone from 92_BB4 to boosted97lude should really be more cordial with eachother. no point in getting all worked up just cause someone didn't use the search function or when they didn't get their answer 3 hours after first posting it.
-ray

Boostless97Lude

*******!!! and damn proud of it

RHD_BB4T

NatakuBlitz,

Thanks for the support and understanding of the issue. Perhaps the best thing that I could have done was ignore imature remarks from people that have been here or seen this topic several times.

Boosted97Lude, (everyone else)

It wasn't my intention to sound, as you put it so eloquently, "...like a smart ***!" YOU misuderstood ME, and I was just hoping that if no-one wanted to take the time to explain, perhaps they could be so helpful as to directing me towards the CORRECT information. I don't mind looking around myself, but obiously (even on THIS forum), not everyone was correct with their responses!

Everyone else,

Thanks for the help, the time, and a little bit of respect and coutesy. I'm not, and don't like to be treated (as I'm sure everyone else as well) like some second-rate punk kid that just got his/her license and has aspirations of being in the next Fast And Furious movement.

Peace!

Dan P.-


[Modified by 92_BB4, 9:32 PM 2/24/2003]


[Modified by 92_BB4, 9:34 PM 2/24/2003]

PrecisionH23a

how do you put on your main seals again? hahah, jk. all you ******* calm down and stop bitching. Dont burn your bridges with other members, we just get sick of hearing the same ******* question asked 49 times a day.

Boostless97Lude

hey bitch, main seals are tricky as ****, and if they don't get put in PERFECT, they still leak

sslude

but if the space isnt filled (like the open deck) what runs throguht htat space? and whatever runs throught that space, what happens without it? thanks

PrecisionH23a

coolant

bb6h22a

Ok, so there have been countless dicussions about the '97+ FRM sleeves, and using forged pistons and so on. Anyway, I've spent a good chunk of time looking into this and I have found out, what I see, as a conclusive answer. Another thing to note is that, not so coincidentally, the NSX's new 3.2 liter motor also recieved the same sleeves, using the same materials and open-deck format. So, using Honda published NSX tech update materials, I think I finally have got it, so here goes:

Part One:

In 1997 Honda announced [could have been present in the 92+ h22's as well] the use of FRM [Fiber Reinforced sleeves which are a combination of Carbon Fiber and Aluminum Oxide, which is a very cleaver coating b/c of its resistance to oxidation and higher wear resistance vs. cast iron liners/sleeves]sleeves instead of cast iron sleeves like they do in all the other motors. The reason they did this was to make the motor lighter and to add cooling capacity to the block; as heat transfers b/w the FRM sleeves and the surrounding water jackets w/ greater efficency than the corresponding cast iron sleeves do.

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The information above is my own interpertation of Honda published information featured in a model year 1997 Prelude tech update brochure/pamphlet.

Part Two:

Looks like in '97 the NSX also got these FRM sleeves and this explains why and how the sleeves, work and states that why forged aluminum pistons are not reccomended:

To increase the displacement of the 1997 NSX to 3.2 liters, the bore was increased from 90 to 93 mm.

Despite increases in horsepower and displacement, engine weight was reduced by 2.4 kilograms. To achieve both light weight and durability, the block is made of aluminum alloy. The cylinders on the new 3.2-liter V-6 are now made using an advanced metallurgical technique called Fiber Reinforced Metal (FRM), in which an alumina-carbon fiber is cast into the traditional aluminum alloy for enhanced rigidity. This process not only allows displacement to be increased without increasing bore centers, it also provides outstanding cooling characteristics.

The NSX's block has cylinder bore surfaces consisting of an 0.5-mm-thick layer with fibers of carbon and alumina (aluminum oxide, or Al2O2) in the aluminum alloy. In production, the cylinder block's aluminum alloy is poured around cylinder cores composed of these two fibers. The cores absorb the molten aluminum during the casting. After casting, the cylinders are bored to a slightly smaller diameter than the cores, leaving a tough, wear resistant, composite cylinder wall integral with the block but reinforced by the fibers. The process allows larger bores within the same external block dimensions and bore spacing, and makes open-deck block construction possible. In turn, this is appropriate for the new NSX engine's higher performance level. And with the elimination of iron cylinder liners, the reduction in engine weight by 2.4 kilograms was made possible.

In engines with steel cylinders, conventional aluminum pistons are normally used. Because aluminum-on-aluminum is not a satisfactory combination for durability with a piston sliding in a cylinder, the NSX's aluminum pistons are given an iron coating.

The information above was taken straight word for word out of the 1997 Honda published NSX tech update! Also, it is worth mentioning that boring of '97+ NSX motors is also not reccomended for the reason used for '97+ h22's!

There you have it, the FRM sleeves have, as an integral part, Aluminum which will not provide proper sealing when combined w/ a forged aluminum pistons, hence the comment about the piston sliding in the cylinders! That's why the pistons are coated w/ IRON!!

Also, at this point weather or not Nikasil is present on the FRM sleeves is up in the air, the Helms makes no mention of it while other people go on and on about it. Another thing to account for would be the rings, the 97+ h22's have specially designed rings, so it could be possible that you don't get proper seating w/ aftermarket rings and/or pistons.!


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Also, refer to these posts from other forums:
(1).
https://honda-tech.com/zerothread?id...=847019#847019
(2).
https://honda-tech.com/zerothread?id=121765""

nastylude

i guess no one else took the time to notice its a B-series block? and whats up with all the colors?

PrecisionH23a

i guess you didnt take the time to notice that he was just posting to show the difference between a closed deck and an open deck block.

nastylude

im very well aware of what he was trying to do, however his picture of a b-series block with a block guard accomplished nothing that the og thread asked for.