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3.0L VS 2.5L  

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  R34NRG said:
okay okay.

ill say it again.

im not saying 25s are SHIT. im saying that 30s are better. understand people??!??!?!

i love 25s, been driving one since i got the car. but since upgrading to 3.0L its just a no brainer why id never go back to 2.5

look carefully at the graph, an RB30 might match the response, but probably wouldnt be any better

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it depends on what you want. mine is a budget build 25de/30e with a 25 hiflow. it makes 250rwkw odd and far to much torque for a street driven R32. een with good suspension setup and decent 235's i have no useful traction after 4000rpm in 1st 2nd and sometimes 3rd.

infact a 25 with the same turbo and an equal tune would be faster from 0 to 100.

however if you want to drift it. push it into a corner in 3rd or even 4th and stamp the throttle and instant sideways action.

fantastic for putting around as i can comfortably do 40 to 50kph in 4th at low revs with huge torque but useless for acceleration at low speeds.

they are different engines for different needs,

granted my turbo is probably to small and comes on like a 150 shot of nitrous.

  CEF11E said:
it depends on what you want. mine is a budget build 25de/30e with a 25 hiflow. it makes 250rwkw odd and far to much torque for a street driven R32. een with good suspension setup and decent 235's i have no useful traction after 4000rpm in 1st 2nd and sometimes 3rd.

infact a 25 with the same turbo and an equal tune would be faster from 0 to 100.

however if you want to drift it. push it into a corner in 3rd or even 4th and stamp the throttle and instant sideways action.

fantastic for putting around as i can comfortably do 40 to 50kph in 4th at low revs with huge torque but useless for acceleration at low speeds.

they are different engines for different needs,

granted my turbo is probably to small and comes on like a 150 shot of nitrous.

yeh way to small for a engine that size to be honest.

like i said above i would only opt for a 3.0L if aiming for 300+ any less its to much of a light switch action. although with some drag radials it be insane.

  CEF11E said:
i have been thinking that.

on a getech with low pressure in the rears and me having no experience in drags it still will pull 12.0 flat

its not all that bad, at least you can upgrade to some gt28s or even a 30 or 35 later on. make some more power when your more comfident.

might have to upgrade fuelpump/injectors if you havnt planned it though

Most people have never driven an rb30det, so have no idea what the differences/gains are.

When i built my rb30det, i did it in a way that i would have done if i wanted to build an rb25det. I didn't down-grade to a rb25de head and waste more money. The only extra costs to do an rb30 conversion are as follows:

- rb30 block = $80-$120

- VCT oil line = $100

Not sure if there was anything else, so lets just add another $200 for the hell of it.

Grand total: $400 extra

All other mods would have been done on the rb25, if i chose to go down that path, and would have cost just as much.

How many rb25's make 140rwkw, in 4th gear at 80km/h? (Mind you this is in run-in tune.)

How many 300rwkw rb25's make full boost by 2800rpm?

Every rb25 dyno sheet i have seen is making almost half the power and torque in the low rpm range.

I have posted my dyno comparisons numerous times, so i'll not post them up again :laugh:, and the low-mid range is mind blowingly great!

Rb30's do not produce greater peak power, just like the rb25 Vs the rb20, peak power is pretty much the same, using the same mods, it's USABLE POWER or the AREA UNDER THE GRAPH that makes the rb30 such an awesome package.

People love taking about "band for buck"; so for less than $400 i have doubled the low-mid range torque and power. What other mod can have such a significant impact for the same price?

PS: My rb30det will have a rev limit set to 8000rpm; the only thing that will change this is if the turbo runs out of puff before then, as i have fitted the smallest recommended turbo.

  R34NRG said:
ive proved my point, so im done with this thread. i hope everyone links to this thread wen ppl talk shit about rb30.

theres a dozen votes for RB25, which no one has yet to clarify why. only a personality pick, dosnt really count but i wat ever.

mods can do wat they want with this thread

im out

as requested - thread closed

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