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Standard Vs H Or I Beam Rods

Turbz_13

By Turbz_13,
in Engines & Forced Induction

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Turbz_13 Experienced

Turbz_13

Posted
Posted (edited)

how are ya guys, now im facing kind of a hold up with my rb rebuild. i dont know what type of rods i should use. i kno there is about a 2 grand diff in price including balancing etc. but i am still not sure what i should use.

i will be say chasing after 350 4wkws as a ball park figure (which is about 400 rwkw's i think) and i really only want to rebuild this engine once.

what should i use?

cheers guys

Edited by Turbz_13
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djr81 Grand Master

djr81

Posted
Posted

For that much hp you should be using aftermarket rods.

The differences between H & I patern rods (In terms of performance) is less than some people make out. H pattern (for the same weight) arguably have a lower rotational inertia hence are favoured for high revving motors. I beam rods have a greater stiffness in beding along the crank axis. Best bet is to find one you like (in terms of stated strength) & price.

djr81 Grand Master

djr81

Posted
Posted
Stock rods are more than adequate

I ran 369rwkw/24psi on stock GTR rods for around 6 months. No issues.

I know of people making a fair bit more and for a fair bit longer :thumbsup:

Hmm, I take the view that for the kind of money you need to spend to get 500rwhp or thereabouts & if you are opening up the engine why wouldn't you spend the extra for the rods?

But like you say it can be done on an unopened motor or with crack tested rods.

Turbz_13 Experienced

Turbz_13

Posted
  • Author
Posted

and if i keep the car i really dont wanna have to open it up again to replace inturnals after they died from to much power. if i get the power i want. just thought i better add that bit

R31Nismoid Grand Master

R31Nismoid

Posted
Posted
Hmm, I take the view that for the kind of money you need to spend to get 500rwhp or thereabouts & if you are opening up the engine why wouldn't you spend the extra for the rods?

But like you say it can be done on an unopened motor or with crack tested rods.

I take the view, spend the money where its required, not where you dont need too.

Most people are on a budget of some kind in most cases.

All well and good if you dont have a budget, but if you can save a few bob, why not.

I didnt say an un-opened motor at all :P

My example, and references were to motors that have ALL been opened up.

The all run a set of forged pistson, stock rods and stock cranks plus everything else that goes into a rebuild.

My car itself was an RB25 with GTR rods.

fEkuaR Experienced

fEkuaR

Posted
Posted

Personally if i could afford it id deffinately get a new set of rods just for the self reasurance that the engine will be up to the task. Im not debating whether the standard rods would be good enough or not. Though myself i wouldnt want to push standard items that far after spending huge dollars on everything else in a setup that could achieve that sort of power.

Id spend the extra cash sell the standard rods for a bit towards them and feel a little more confident when i put my foot down that all will be alrite.

Just depends if you have the cash...

Gav Mentor

Gav

Posted
Posted

If you get "crack testing" done, make sure you know exactly what type of tests will be performed.

Personally I would only recommend x-ray testing as magnetic particle testing, although cheaper, isn't as reliable for detecting stress fractures on for complex shapes like rods.

Turbz_13 Experienced

Turbz_13

Posted
  • Author
Posted (edited)

so looks like standard rods are stronger then i first through. i may just use a new set of 26 rods in my rebuild then. save me 2 grand and buy a haltech insted

Edited by Turbz_13
Turbz_13 Experienced

Turbz_13

Posted
  • Author
Posted

my budget is about 10k, would have be fine and could have dropped h beams in if they didnt find a few other things wrong. so now i need to do the best possible for the cheapest!!! with the power figure still in mind

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