OFFICIAL ROSTEN RODs THREAD (ROSTEN vs OEM pics - BWW)

[MiniRS4]

i have no idea how that tiny lil bolt is stronger than that big ole OEM one. ARP, tho...








FYI, notice how the OEM rod is rough where they meet... that is bc they are cast in one piece and then cracked apart.

TINY LIL ARP BOLTS...



549.4


582.5


---------------------------------------------------------------------------------------------
Thoughts...
(Jared please share your pics)

PRICE: $1250 retail/shipped


582.5
549.4
------
-33.1
x 6
------
198.6

sorry for the super large text... lol... make it official... now we know the exact weights of these rods.

33.1 x (6) = 198.6 grams of weight savings from the bottom end/rotating mass should provide some sort of performance, even if marginal. soon we'll find out... and we'll also find out what they can handle. cuz, ill be throwin all i got at em. boost or bust. that is all.

ps- if yall know any other rod brand weight pls post - n dont hack this thread. Thank you.

[generationjdm]

almost half a pound in saving

[jibberjive]

did the ARP bolts come with the $975 price?

[JayyyyyC]

Anyone know if Pauter also makes rods? They've had a very good rep with VWs but don't know if they have stuff for the S4.

[PinoyS4]

h-beam rods ftmfw

[Boris]

How about some Forged rods?

btw, after you install the con rods, what is needed to balance the engine? Are ARP's actually just replace and ready? Someone mentioned that on here once, is that correct? If not, whats involved in balancing an engine?

[pdq 5oh]

The cracked cap technology makes the rod caps line up better. Rods with dowels are a better setup, but more expensive to produce. The ARP bolts are a different metal and are tempered differently. They are much better re: tensile strength and stretch.

Boris, these are forged rods. Balancing depends on the use of the harmonic balancer and flywheel. Most factory engines use an imbalance setup. The crank damper and flywheel are weighted to offset the imbalance of the rotating assy. Zero balance uses balanced damper and flywheel with no imbalance to offset. Zero balance is the better way to go. It's all about defeating harmonics that degrade performance and beat motors and drivetrains to death.

[MiniRS4]

did the ARP bolts come with the $975 price?

YES, or course. almost all rods come w a preferred size and brand of bolt w it. most being ARP something or other. these have ARP 2000 bolts (tiny).

Anyone know if Pauter also makes rods? They've had a very good rep with VWs but don't know if they have stuff for the S4.

Yes, they def make rods for us. in fact, i believe they weigh and cost more. but to get it right (apparently) you have to get in touch w Pauter first and send them one of your own. the reason being is bc apparently there are 3 diff rods for our cars. n he sends you the exact one, not just some 1-size fits all. do you guys remember Jeff Moss w the RS6 build. the car that was in the magazine. he experienced this w Pauter.

How about some Forged rods?

btw, after you install the con rods, what is needed to balance the engine? Are ARP's actually just replace and ready? Someone mentioned that on here once, is that correct? If not, whats involved in balancing an engine?

* 2.6 liter
* 2.7 liter biturbo
* 2.8 liter
* DO NOT FIT 2.4 and 3.0 liter V6
* 154mm center - center
* 21mm small end with bronze bushing
* 57.6mm big end
* 2piece forged from 40CrNiMo steel
* shoot peened and heat treated
* comes with ARP 2000 bolts and assembly instructions
* weight is 555 gram included bolts - funny, it is actually less
* with a tolerance of +- 1gram

as for balancing etc... i do not know the exact process. and as for bolts... i think you may be referring to the matrix con-rod bolt thread. these are different size bolts than the M8.5 OEM bolts. random factoid... RS4 uses M9 OEM con-rod bolts.

[ss4]

Anyone know if Pauter also makes rods? They've had a very good rep with VWs but don't know if they have stuff for the S4.

Yes, Pauter makes an awesome rod for this motor. Have them in my car...

[JaredVL]

Price is wrong, that was part of a group buy. Wont happen again.

[2001S4NY]

cant wait to get this bad boy running :)

[MiniRS4]

Price is wrong, that was part of a group buy. Wont happen again.

LOL! thanks for sharing.

[JaredVL]

Good thread and info man, thanks. Here are a bunch more pictures. Prepare for info overload...

Btw- These are the s4 fit, there is also an RS4 direct fit.

The only difference is the big end bore.
56.8mm on the RS4
57.6mm on the S4

[BITRBO]

almost half a pound in saving

yep, about 0.43lbm to be exact. but you'll see much more in terms of linear & rotational inertia, which is what is important. if someone has the exact rod dimmensions handy (or *dwg files better yet!), I could calc. this value...

otherwise, just suffice to say the engine rev more freely, possibly in comparision to a LWFW.

[MiniRS4]

yep, about 0.43lbm to be exact. but you'll see much more in terms of linear & rotational inertia, which is what is important. if someone has the exact rod dimmensions handy (or *dwg files better yet!), I could calc. this value...

otherwise, just suffice to say the engine rev more freely, possibly in comparision to a LWFW.

Jared, post those dimension pics so i can see this math!!! thanks in advance!

[JaredVL]

Done

[BITRBO]

Jared, post those dimension pics so i can see this math!!! thanks in advance!

damn.... called my bluff well I'll give it a whirl next week after I get the P.E. out of the way (this Friday).

which reminds me... I shouldn't even be on here

DOHPE!

[Europowerhaus]

its too bad a 5/16th rod bolt is the largest these rods can take, a 3/8th would be sweet

[Europowerhaus]

also the reason why they look so tiny is because they only need a small amount of threads, they are special rolled threads that companies like arp specialize in :) Strong shit

[Boris]

Boris, these are forged rods. Balancing depends on the use of the harmonic balancer and flywheel. Most factory engines use an imbalance setup. The crank damper and flywheel are weighted to offset the imbalance of the rotating assy. Zero balance uses balanced damper and flywheel with no imbalance to offset. Zero balance is the better way to go. It's all about defeating harmonics that degrade performance and beat motors and drivetrains to death.

Sorry, I thought Forged was a brand as well as being a type of con rod


Hey, are their any con rods that can be repalced into the s4 engine that are just plug and play, with no need to balance or anything? Just replace?