Alright this is the deal, I have Mahle gold series pistons, and I need as much info as I can get so all the help with this is appreciated, I have a H22a vtec, does any one know any thing about these??? I know a little bit about them, but not as much as I want to know. I need to know if I would want to use a block guard, and if so what kind??? My bore size is stock 87.00/3.425 So please if you know any thing about this thank you very much.

 

Know anything about them? They work in FRM sleeves. The rest is up to the specific piston.

What do you need a block guard for?

 

I was told that a block guard is needed, with these pistons??? I guess not... Yea I bought Dartten sleeves, and the guy that was putting them in was like you dont need those, so im just seeing wut peoples openions are on this.

 

Darton sleeves don't require mahle pistons. Sell them and get lighter forged pistons. I recommend Wiseco.

you don't need a block guard with a sleeved block.

 

Yea I under stand I dont need a block guard with a sleeved block. Do I need a block guard with those pistons, if I didnt do the sleeves???

 

x2 with no block guard. If you are going sleeved, why don't you use forged as stated, there are many to choose from wiseco, cp, arias, etc. I have cp in my setup with darton flanged sleeves. Why are you sleeving in the first place? What happened to the car?

 

Im going turboed, and I have Mahle Gold series Pistons

 

I'm doing the machine work and building this motor, and i happened to come across this post, so let me clarify a bit.

If we did this engine with the mahle gold's, and no sleeves, would the block guard be necessary? if so we'll have to swap the pistons for an oversize because from what i've read, you get some bore distortion with the block guards, correct?

And approx. what have you guys been spending to get these things sleeved? I don't have the machinery to sleeve one, and was told to expect to pay about 1800-1900. Thanks in advance for any help.

 

wtf???

 

first off. if you use the mahle pistons..no need to resleeve. if u still resleeve go with the bore of the pistons. block gaurds are not needed

 

an resleeving is about 1000-1500 max for soem darton mid's

 

i got flanged darton sleeves put in for like 650 I believe a few months ago. MID's are harder to put in, but are a lot stronger than flanged sleeves.

 

ok...i'm a professional machinist, not an idiot, just not super experienced with honda motors.

I'm well aware that the sleeve's aren't needed with the mahle gold pistons, which is why i said "with the mahle gold's, and no sleeves"

What i was asking is whether or not the block guard is necessary when using MAHLE PISTONS AND NO SLEEVES. Can H22 blocks handle any boost w/out the guard? and if so, how much?

And the last question that went unanswered...what have you guys experienced as far as bore distortion after installing a block guard? none? lots? or does it differ between guards?

 

i used a block gaurd in my b20v all motor car. never had a problem. but there really not needed. right now im a stock block running 7psi for right now with no problems. this week im putting 8.5.1 wisecos with just using replacement iron sleeves..not the mid's. but no, the block isnt nessesory.

 

dude you should have really done your own research. mahle makes there pistons for the point of not having to re sleeve. which can start at 1000 and go up. you dont need block gaurd and you dont have to sleeve it.

 

lol he knows that so shhhh. Do you have the block guard already? If you do then use it, if not woulden't worry about it. Your not planning on running like 20psi on mahles are you?

 

He has the block guard already, i think it's a KWM piece. And we have mahle's in std. bore.

My concern though, is that i read that if you use a block guard, you get enough bore distortion that it's necessary to go to oversize pistons so that you can get a nice round cylinder again.

Am I misinformed??

 

Block Guard will egg shape the cylinders. This is an open deck from the way you talk. I had my deck bore sleeved and then rebored to fit pistons for 500.00. Your best bet is to send back the Mahle pistons, use the sleeves you bought and buy new forged pistons. Case Closed. Because I dought you can Hone the cylinders which are made of FRM. Not saying it cant be done.

 

Block gaurd is used for open decks for people who choose not to run a mid block sleeve.

 

Last but not least you can ran boost on mahle pistons, stock pistons but how much boost is dependednt on how good of a tune is in the car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheMonkeyProject &raquo;</TD></TR><TR><TD CLASS="quote">ok...i'm a professional machinist, not an idiot, just not super experienced with honda motors.


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I don't have a Crystal Ball...but...PLEASE TAKE YOUR TIME!

 

mahle pistons do not require a over bore... just a slight hone, from what i remember, i was planning on going with gold series pistons from them but when i went the place to order a year and a half ago, they were outta stock and none were to be made in the next few months... call and talk to mahle's tech dept, they have two guys there and one of the ones is the engineer who designed the piston... he will tell you what you want to know about the piston...

From wat i can tell/remember the rings and the skirts are the two biggest contributers...(note: also if im not mistaken in the pictures i was looking at the piston skirt is also champered at the bottom)

 

take the Gold series Mahle pistons back where you got them and exchange them for the Mahle pistons that are not the Gold series and you'd be better off IMO....

as far as the block guard is concerned-it really only matters if you are planning on big boost (like everyone is saying).....

 

so your advising him to go get mahle normal *** pistons and throw them in a stock block and go boost...

A block guard is a sorry excuse for a sleeve... it's a copy cat sleeve, it's supposed to be frozen then pressed into blocks water jacket... as for it's true purpose it's to keep your cylinders from warping and wabbling due to extreme heat and pressure, so it's reinforce at the top of the block, because the water jacket is not strong at the top like it is on the bottom.. as for high boost (without a good tune, not a good idea)

If you can afford it... just sleeve it, save the trouble

 

a block gaurd isnt surpossed to be pressed in. "snug fit" to allow some expansion of the cylinder walls