I went to DPR Tuning today and asked a few questions about their new forged pistons they just came out with. Knowing what I hear everyone preaching on this forum about how you can not use Forged pistons because of the FRM sleeves I asked whether I had to re-sleeve to use the pistons. I was told that it is not necessary to re-sleeve a H22 block unless it is bored 1mm or more over do to the wall thickness being too small. I have never heard of this before..why is that? The shop is very reputable and I know they know their ****...

 

Cant realy get into to much detail cause im at work, but you have to re-sleeve your block in order to use forged pistons.

 

ya ya i know people say you have to...Unless I was feed a line of Bullshit, I don't understand..

 

they don't know enough about H-series obviously

 

So DPR came out with the pistons? What are the design specs of the side skirts exactly? Are they coated?

If they are so sure they will work fine and not gum up with FRM sleeves, have them write this up in a contract that if they fail that they will replace everypart that malfunctions due to not re-sleeving.

Personally I wouldnt be the guinea pig for the new pistons... How much power are you looking at running? You know a motor is only as strong as it's weakest link...

 

Don't risk it, sleeve the block.

 

get the jun pistons they work, unless you are going forced induction. big money though.

 

Are forged juns too weak for FI?
pentaq

 

juns are most likely super high compression

 

Jun Pistons can you get away with out re sleeving?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GudeH23a &raquo;</TD></TR><TR><TD CLASS="quote">So DPR came out with the pistons? What are the design specs of the side skirts exactly? Are they coated?

If they are so sure they will work fine and not gum up with FRM sleeves, have them write this up in a contract that if they fail that they will replace everypart that malfunctions due to not re-sleeving.</TD></TR></TABLE>

http://www.pure-tuning.com/ Link to the Homepage
http://www.pure-tuning.com/pag...r.htm Link to Pistons

I am not sure about the specs yet. The pistons are still fairly new, and I was going to check into them with research before I put my money and motor on the line. Yes i will get a contract with them, but the contract won't cover **** because I will be running nitrous for one, and If they do not install the pistons themselves, they won't trust that I will do it right and just blaim it all on me. This is not some ghetto shop due to the fact that they have lots of experience to back them up including magazine coverage in Honda tuning for their H22 build up they did and I see their name in random photos all over the place.

 

I dont see anywhere where it states you dont need to sleeve the block.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2kflamedlude &raquo;</TD></TR><TR><TD CLASS="quote">I dont see anywhere where it states you dont need to sleeve the block. </TD></TR></TABLE>

Its not on there site, I went into the shop today and talked with them for like 5 minutes. I just asked if i had to re sleeve using there forged pistons, and he said no, only if i bore it out over 1 mm. I didn't have a whole lot of time to talk so I didn't ask him anymore questions about it. I am gona give them a call or stop in tomorrow and ask a few more questions.

 

Man i would be kind of weary on that.. Same thing with the Weisco pistons.. People say dont need to resleeve. But I found out that you do have to.

 

I am VERY weary about it. Im gona go talk with him in depth tomorrow about it, but I wana have a little more knowledge about the subject.. First off, why is it the Forged Aluminum does not work with Fiber Reinforced Metal? Is it because of the properties of Aluminum and FRM like hardness, tensile strength, torsional, brittleness, ect? What Exactly is the sleeve made of? Would the design of the skirt really matter considering it is forged aluminum? What special coating would allow for these pistons to work with the FRM sleeve? I just finished taking a Metal Machining class and could look in the book to find out more about metals and there interaction together.

 

Yep, they are sure coated alright. That frictionless coat may be what allows the piston to run in a FRM lined cylinder. Now, which rings do they suggest using?

Personally, I would resleeve just for the extra sense of security. Thats one less thing you have to worry about in the corner of your mind when you are on the dyno or at the strip.

 

[QUOTE=2kflamedlude]Jun Pistons can you get away with out re sleeving

absolutly 100% yes. just think the s2000 has forged pistons with frm walls stock.

 

Nice You know where I can order up a set? Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by junbb1 &raquo;</TD></TR><TR><TD CLASS="quote">[QUOTE=2kflamedlude]Jun Pistons can you get away with out re sleeving

absolutly 100% yes. just think the s2000 has forged pistons with frm walls stock.
</TD></TR></TABLE>

Still the thought of putting forged pistons in those sleeves make leery.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2kflamedlude &raquo;</TD></TR><TR><TD CLASS="quote">Nice You know where I can order up a set? Thanks </TD></TR></TABLE>

i beleive titan motorsports is an importer of JUN products.

 

Do you happen to have the URL?

 

Have some of you ever heard of google.com? You can find out anything with it:

http://www.titanmotorsports.com/

 

eh.. i tried yahoo search thanks

 

I didn't ask what rings they suggest, but they come with rings when you buy the piston. When you say they are coated, are you talking about the frictionless coating as referred on the HR pistons?

 

The skirt coatins will help to make then last for a while.i suggest using oem rings with these pistons if the piston to wall clearance isnt too sloppy."treated" forged pistons will work,but i wouldnt expect it to last as long at it would with stock pistons.