Rb26 Conrods

[GTRPowa]

Sup, what's 'general' limit of conrods? It is based on power? boost? RPM?

What's the ideal time you'd be looking at upgrading conrods in an RB26? I'm doing pistons soon, and after some searching, I haven't come to a consensus about whether I need to upgrade rods too. What will upgraded rods give me?

Expecting about 370-380awkw.

[pnblight]

Std rods are pretty good i ran 397rwkw for 2 to 3 years on stock internals, so they can handle it just watch the revs as revs it what destroys rods (keep std redline and you should have any problems) if you do keep them it would be worth installing new rod bolts (like ARP) good insurance.

Pete

[R31Nismoid]

stock rods have held with 440rwkw on a number of cars, 8500rpm no problem.

so for you, they will be fine.

using decent rod bolts is an absolute must for it to work.

[DVS JEZ]

yep as above, i had 419kw with stock rods and arp2000 rod bolts,

what pistons are you using?

[Beer Baron]

yeah they can and do hold plenty of power. for my personal engines though? I'd say if your target is a genuine 350KW+ at all 4 then you should get some rods. if you only want "up to" 350kw atw then standard is fine. it's just that once you get some big power it's nice to have a stronger, lighter rod in there for insurance.

[GTRPowa]

Ok then. In the realm of rods, what's a good 'bang for buck' rod? Seems I'll be sitting somewhere in the $1000-1500 mark. Special place that does them? I might even look into these CRD bottom ends. They do block exchanges for somewhere about the $5k mark, blueprinted, forged parts etc. I just dont know if that includes rods.

(I'm not experienced in the field of RB rods and pistons, but I assume I'll be well versed by the time I make my choice.)

[djr81]

yeah they can and do hold plenty of power. for my personal engines though? I'd say if your target is a genuine 350KW+ at all 4 then you should get some rods. if you only want "up to" 350kw atw then standard is fine. it's just that once you get some big power it's nice to have a stronger, lighter rod in there for insurance.

Ok then. In the realm of rods, what's a good 'bang for buck' rod? Seems I'll be sitting somewhere in the $1000-1500 mark. Special place that does them? I might even look into these CRD bottom ends. They do block exchanges for somewhere about the $5k mark, blueprinted, forged parts etc. I just dont know if that includes rods.

(I'm not experienced in the field of RB rods and pistons, but I assume I'll be well versed by the time I make my choice.)

There is a little company called Carrillo who make nice rods. H or I pattern, take your pick. Just over 500 grams for a rod with bolts for the heavy duty rod which is about 120 grams less than stock.

So less reciprocating mass & more strength. Win, win. Your budget is about right.

[GTRPowa]

There is a little company called Carrillo who make nice rods. H or I pattern, take your pick.

I'll check them out. What's the main differences between H and I rods? (Besides the fact that one's a H and one's an I)

Edit: From what it says on Nitto site, I beams are better. But still, I don't think I'd need to go that far..

Edited January 28, 2011 by GTRPowa

[djr81]

I'll check them out. What's the main differences between H and I rods? (Besides the fact that one's a H and one's an I)

Edit: From what it says on Nitto site, I beams are better. But still, I don't think I'd need to go that far..

The I section versus H section argument is about as interesting as shovelling muck. In this case the H pattern rods are marketed by Carrillo as being stronger.

http://www.cp-carrillo.com/Tech/RodTech/tabid/76/Default.aspx

[Beer Baron]

yeah agreed you could argue about H vs I (don't even start on proprietary designs like "X beam" etc)for years and still not come to a solution. I agree carillo rods are great. very good quality and with the weak USD vs AUD very cheap to buy right now so they would certainly be a good choice and within budget.

[GTRPowa]

Unanimous. Thanks for the info.

[JustinP]

Could someone please confirm that the R34 RB25DET (Neo version) uses the same rods as the GTR?

And therefore if you were rebuilding that engine with forged pistions that you could fairly safetly get away with using the stock rods if were never going to go for much more that 300rwkw? Obvioulsy would change rod bolts though.

Thanks

[djr81]

yeah agreed you could argue about H vs I (don't even start on proprietary designs like "X beam" etc)for years and still not come to a solution. I agree carillo rods are great. very good quality and with the weak USD vs AUD very cheap to buy right now so they would certainly be a good choice and within budget.

There are a few vendors in the States (A few, a hundred....) from which you can import. Not sure if Summit list them, however. You will avoid import duty but may get stung for GST. Still at about $1k + shipping & taxes they are good value.

As an aside is there as equivalent forged piston thread out there? I looked & didn't much like the CP's (Mostly for the O/S valve cutouts), wasn't 100% sold on the Mahles (Clashed with oil squirters) & dont know much about Wiseco. The Japanese stuff appears to be expensive & I bereft of coatings. Any ideas?

[Beer Baron]

hmm, tough call. CPs probably the most popular these days. wiseco not so much. the jap stuff is good but like you say costly. I'm using tomei pistons in my current engine and I have to say they are super quiet. compared to other local forged engines there is zero piston slap when cold (or hot for that matter). HKS pistons come with various coatings like moly coated skirts, titanium coated ring lands and ceramic coated crowns but cost the earth if you option them up that far.

ummm, there must be other options. what about Ross pistons? not sure from memory if they have the big valve reliefs cut in them too.

[Supa Steve]

Red R Racing in Newcastle has tested stock conrods with ARP's in a race engine for 3 years and ran over 600hp and 9000rpm so they are well made. They also have an excellent little end bush that can certainly take some treatment. Paul convinced me to spend a little more and get the Nitto rods as they have the little end bush material spot on and are streets ahead of some of the China based rebranded offerings. He also showed me a (insert brand name here) conrod and explained/demonstrated that there is more to a conrod than looks, structure and material used. The cheaper conrod bush was oval with very little use and when measured up against the stock bush in his old race engine was woeful. He also explained that the cheaper rod was basicly ok but by the time you spent the $$ on them to get them up to scratch it was more cost effective to either resize and rebolt stockers or by the more expensive Nitto or Carillo items. The Nitto rods have made around 1000kw in one of Pauls engines and also look the goods.

Mahle pistons come highly recommended also.

Edited January 28, 2011 by Supa Steve

[djr81]

hmm, tough call. CPs probably the most popular these days. wiseco not so much. the jap stuff is good but like you say costly. I'm using tomei pistons in my current engine and I have to say they are super quiet. compared to other local forged engines there is zero piston slap when cold (or hot for that matter). HKS pistons come with various coatings like moly coated skirts, titanium coated ring lands and ceramic coated crowns but cost the earth if you option them up that far.

ummm, there must be other options. what about Ross pistons? not sure from memory if they have the big valve reliefs cut in them too.

I quickly checked the Tomei price. Cooling channel version $3000 for the six, normal version $1780 delivered. the Mahle pistons are approx just over half as much.

As far as coating go I wasn't bothered with titanium this or that, or ceramic coating the crowns - more interested in a low friction coating for the piston sides.

HKS - part number 2103-RN017

lists as $2124 delivered.

2103-RN021 lists as $1585 delivered.

So the Japanese stuff doesn't appear to be particularly good value. It may, however, be more suited (As opposed to more generic although that is just conjecture)

How do Mahle pistons go for noise?

I'll have a look for Ross stuff also.

Edited January 28, 2011 by djr81

[r33_racer]

Mahles are good. Though last I heard from ACL distributor Nasons they were moving to China for manufacturing, dunno if thats happened yet.

Ross are good. Slightly heavier, though a tougher piston but you need more piston to bore clearance for them which results in abit of piston slap when cold but no big deal. The Ross's come with a better ring package then most; thicker rings.

For the power level your chasing a set of Spool rods will handle it all and more just fine if you dont want to stick with the prepped stock rod route. Very cost effective when comparing to other brands too.

[R31Nismoid]

Wiseco are a common choice down here. More motors with those than any other.

[bigmikespec]

Mahles are good. Though last I heard from ACL distributor Nasons they were moving to China for manufacturing, dunno if thats happened yet.

Not to dwell on pistons so much as this is a thread about rods... but, man that sucks!

[JonnoHR31]

Could someone please confirm that the R34 RB25DET (Neo version) uses the same rods as the GTR?

And therefore if you were rebuilding that engine with forged pistions that you could fairly safetly get away with using the stock rods if were never going to go for much more that 300rwkw? Obvioulsy would change rod bolts though.

Thanks

correct, neo's have gtr rods