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i'm just after people opinons on this,

I'm up for a rebuild at the mome and don't like to do things half arsed lol, narrowed down my choices to 2 setups

a gt3040R on a worked 25 or a gt3540R on a worked 25/30

i will be looking to get proengines to do the build regardless but does anyone know of them doing a rb25/30det before? and at what sort of cost?

as far as i'm aware there still in a transition state at the moment so i don't want to bother them just yet lol

and basically what i'm after is more than 300rkw with as little lag as possible

budget 15g but of course would like to stay below that by a fair margin if possible :)

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okay no reply's but justing letting ppl know that'll i'll be able to tell you all if it's worth it :)

not going all out cos i picked up a standard just built 25/30 for a damn good price picking it up this sunday, my cars currently at autotech having the 25 pulled, it will be interesting when's it back together with the same set up as what was on the 25

I guess it will show straight away what differnce the extra .5L makes, i'm thinking bigger turbo will be a definant requirement and is first on the list to be done

figures are one thing, but what i was meaning it will be real interesting to actually feel the differnce in the exact same car with same mods on to primarily standard motors except one 2.5 one 3l i'm looking forward to it

Edited by Slither

I would love to go the 3 litre. and if the rb20 should die i will be doing a rb25/30 budget build. you will dfinatly feel the difference.

mainly the torque as soon as you put your foot down even at low revs.

Booo, truck engine.

Shouldve done a 26 so it can rev its ass of :)

lol not so actually can still be pushed till around 7500 standard, with full rebuild 8000+ should be reachable I'm going back to factory 7000 just to play it safe, will be interesting to have full boost a 2000 with stock turbo I'll miss reving her out tho till i get a much bigger turbo that is :no:

speaking of which i've heard of trojan doing some no name turbo for a good price that's meant to be surprisingly effective apparantly the burgendy 300+ r33 they did had it anyone heard of this?

Let me know how it goes as i'm just about to pick up an RB30 block for mine. The old RB20 is on its way out so hopefully i'll have the new engine built by then. :ninja:

hook me up with a good price on the gt35 kit and you can even drive it :P

Edited by Slither

Longer stroke + bigger cc's=more torque for anRB 30.

Torque balances power [hp,kw]. The longer the stroke the greater the torque, the less you can hurry the motor [revs].

The shorter the stroke the greater the power, the more you can rev the a#se off it.

But consider torque vs power as the ability to push through a brick wall. A rev happy motor will get to the brick wall quickly, and whack it hard, but it will dissipate its energy quickly.

A torque laden motor will reach the wall much more slowly, and will hit the wall 'gently' but will continue through the wall and out the other side.

Torque is work, power is energy.

Its power that makes you go fast, its torque that fights the headwind.

This is like a tractor pulling a stump out with 80hp vs a car trying to do it with 600hp. Older tractors [the common grey fergie type] are usually two to four cylinder diesels with 50hp small bores, and long stroke crankshafts. F1's [senna, Schumacher] cars are short stroke and [in relation] big bores.

Manufacturers try to find a balance based on expected use for each motor.

I've probably gone overboard here, but you should get the picture now.

Not everything that revs is powerful.

my datto revs to 9k but doesnt make good power until after 4.5k. Its a combo of bore/stroke, if id stayed 1.6L i couldve made 10k revs but it doesnt offer any benfit to 9k in the 1.8L. doesnt bother me as its for track/hillclimb where you revs its arse off all day but itd sauck to drive all day around town.

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