Forged engine build

[funkytown]

an open deck would be ok if you dont want to wind it up in its lifetime a open deck would be fine.

at most up to 270wkw a semi closed is also going to satisfy your needs.

[DacerX]

cdb arent that hard to come by tho

[SubLeggy]

 funkytown']

an open deck would be ok if you dont want to wind it up in its lifetime a open deck would be fine.

at most up to 270wkw a semi closed is also going to satisfy your needs.

cheers for that. little information like this is a big help.

[quote name='DacerX said:

cdb arent that hard to come by tho

yes they are quiet eaasy to come by atm.

[funkytown]

a CDB certainly wont hurt, but will cost you more.

[SubLeggy]

 funkytown said:

a CDB certainly wont hurt, but will cost you more.

cheers for that funky.

i certainly have alot to think about then

[Guest]

 DacerX said:

family man is selling a fully forged 2.5 for 2k cheap cheap

2.5 - V7 sti shot peened rods though...why even bother with aftermarket forged pistons if using stock rods imo.

Do cdb have smaller oil gallerys or web myth?

[marc]

 evowrx']

[quote name='DacerX said:

family man is selling a fully forged 2.5 for 2k cheap cheap

/quote]

2.5 - V7 sti shot peened rods though...why even bother with aftermarket forged pistons if using stock rods imo.

Do cdb have smaller oil gallerys or web myth?

Cus the 2.5 pistons dont like 260wkw and the v7 sti rods do

[Guest]

 marc']

[quote name='DacerX said:

family man is selling a fully forged 2.5 for 2k cheap cheap

/quote]

2.5 - V7 sti shot peened rods though...why even bother with aftermarket forged pistons if using stock rods imo.

Do cdb have smaller oil gallerys or web myth?

Cus the 2.5 pistons dont like 260wkw and the v7 sti rods do

Seems mixed bag -300kw atw as with V8 sti pistons which Im guessing are same material as 2.5? STI rods still end up out of block also so pistons/rods same power limit it seems from very accurate web research but I would say its very reliant on tune. I mean you get people like minaj who rape the bother out of their cars and they dont pop well not yet anyway. Think it was stm who were saying V8 sti engine would handle -280kw atw reliably and theyre weaker than V7 sti pistons and rods like you say.

In regards to fully forged - stock sti rods arent factory forged either are they?

[D-Style]

 SubLeggy said:

id be happy with 220-230kw even. it just come down to reliability in the end hence why id be going with a well known engine builder who knows there stuff.

Reliable/Fast is what id be more after.

What are people thoughts on after market pistons even? i see a few use CP pistons etc.

If this is the case, why bother with this topic?

[marc]

lol internet has abit to teach. There are several types of rods but the main difference is bolt vs stud and nut and they handle power a lot differently. You don\'t see the v7 STI on rods leaving the block often really unless something is majorly wrong!. Not going to debate the topic but bore size also affects the factory 2.5 piston strength from experience and cant comment on FACT for material content but from what ive seen (not from behind my keyboard) they don\'t seem to hold up quite like the 2.0 pistons do.

The ver 8 pistons will take the power if tuned perfect but you get abit of det in there and bye bye hence the forged give you abit of leeway if you get a bad batch of gas etc..

WHAT IM SAYING IS forged pistons with stock V7 sti on rods in a opend deck 2.5 with deck supports fitted is not a bad idea for a mild build with some reliability!

[funkytown]

Agree bore and more importantly skirt design and side loading on the 2.5s puts way more stres son them for a same given output

Which also affects the rod strength. Think about the rod angles

[marc]

yep and not like 257 pistons are floating round everywhere for people to put in open decks anyway and then who\'s to say piston to bore clearance will be within spec hence me saying that block mentioned was a good budged minded block with not a bad build concept for mild torquey 250wkw ish ..

[Guest]

 marc said:

lol internet has abit to teach. There are several types of rods but the main difference is bolt vs stud and nut and they handle power a lot differently. You don\'t see the v7 STI on rods leaving the block often really unless something is majorly wrong!. Not going to debate the topic but bore size also affects the factory 2.5 piston strength from experience and cant comment on FACT for material content but from what ive seen (not from behind my keyboard) they don\'t seem to hold up quite like the 2.0 pistons do.

The ver 8 pistons will take the power if tuned perfect but you get abit of det in there and bye bye hence the forged give you abit of leeway if you get a bad batch of gas etc..

WHAT IM SAYING IS forged pistons with stock V7 sti on rods in a opend deck 2.5 with deck supports fitted is not a bad idea for a mild build with some reliability!

Yep everything Im saying above is web talk hence the question. I do realise theres a few different rods tho. You dont have a pic of them lined up do you? Personally I dont see the sense in the stock rods with forged pistons when the blocks semi now anyway. Rods only $500odd Id rather that insurance and also rods wont limit the block then. Horses for courses I just think headrooms always a good thing.

Quite common for EJ257 pistons to sell on TM new that have been stripped out of genuine blocks being forged.

[funkytown]

also agree - while rebuilding, for the peace of mind a set of rods with anything aimed @ >200wkw is sensible and gives you longer term head room.

[familyman]

I am just excited to be mentioned in a thread where I did not have any input.

I would like to thank the Academy, God, Mom and Dad, and all my supporters out there.

[Koom]

 marc said:

yep and not like 257 pistons are floating round everywhere for people to put in open decks anyway and then who\'s to say piston to bore clearance will be within spec hence me saying that block mentioned was a good budged minded block with not a bad build concept for mild torquey 250wkw ish ..

I\'d agree with this. If its just another $500 for the rods, then its just another $500 for the next thing (maybe some injectors), then another $500 for the next thing after that..... all the little extras add up and if you\'re only heading for 200-250kw, then the V7+ rods are perfectly fine. To go higher you\'re going to need turbo, injectors, etc, etc, etc and then the extra $500 would be just a drop in the bucket, but for a budget build to a reasonable power level, an extra $500 here and there becomes frivolous IMO.

[marc]

It sure does snow ball and aids the getting carryd away I agree....

evowrx do a quick search on google there will be lots of pictures to see the difference. Im not saying its not a good idea, it probably is but gota draw a line where to stop. Sometimes good genough is just that... good enough

Edit:

Left is Ver8 STI on rod, next is as labled, then the next is V1-6 wrx/sti and legacy etc (common rod) and yeah ignore the RH for this topic of learning lol

[Guest]

Isn\'t the fact the v1-6 are forged as opposed to cast make them the strongest rod. Still they didn\'t like 200 kw in my experience.

[Koom]

 ballsrburning said:

Isn\'t the fact the v1-6 are forged as opposed to cast make them the strongest rod. Still they didn\'t like 200 kw in my experience.

They\'re all forged. The later model rods changed from bolts to hold the big end together to studs, which has proven to be stronger.

[Guest]

 marc said:

It sure does snow ball and aids the getting carryd away I agree....

evowrx do a quick search on google there will be lots of pictures to see the difference. Im not saying its not a good idea, it probably is but gota draw a line where to stop. Sometimes good genough is just that... good enough

Edit:

Left is Ver8 STI on rod, next is as labled, then the next is V1-6 wrx/sti and legacy etc (common rod) and yeah ignore the RH for this topic of learning lol

Yip plenty of pics on the net but I was more after what you have pulled out of engines in NZ. Arent V8 sti dif to V7 sti also? Or is the JDM V7 the same as sti version?

Regards to rods Ill stick to my guns coz its fun, Im stubborn and really if youre gonna put in forged pistons that are capable of megawots then do the rods to match. Injectors/added expenses cant really be compared to making the shortblock capable to 350kw rather than being limited to 250kw by the rods. Otherwise EJ257 pistons along with V7 sti rods will acheive your 250kw torquey lustings. And yes based pretty much purely on RAC\'s build.

All pulled out of my arse including the kw figures so dont take me out on it.

[marc]

Dont worry mate not trying to win anyones vote lol. If I removed them doesnt make them look any different to the picture hence my little recap explanation? Look at the picture and you will see the 8 rods are different to the 7 going by what i said at the bottom of the image. & JDM v7 in the pic is same as V7 STI yes. In NZ the "JDM" stuf is the same as WRX non sti.

[Guest]

Yea I thought the taper on the V8 sti rods was the difference to the V7 sti rods but only from web reading so after confirmation. So the JDM V7 one is sti or non? the cap looks weaker on the V7 one as opposed to the V8 sti in pic.

[marc]

 evowrx said:

Yea I thought the taper on the V8 sti rods was the difference to the V7 sti rods but only from web reading so after confirmation. So the JDM V7 one is sti or non? the cap looks weaker on the V7 one as opposed to the V8 sti in pic.

Yeah taper is the main difference and yes the bigend cap design varys from years from what ive seen and doesnt seem to be any weaker at all. Visually looking at somthing espesh in 2D doesnt tell you much.

V7 JDM in pic is same as our V7 STI. Theyr ither STI or not over here.

[D-Style]

What is it about the rods that fail? do they break? bend? Cap bolts/studs break?

[Guest]

 D-Style said:

What is it about the rods that fail? do they break? bend? Cap bolts/studs break?

Mine snapped at the thinest point of the rod. then broke free through the side of the block.