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Old Mar 19, 2015 | 12:54 PM
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Default Boost difference between UK and JDM?

I was under the impression that the JDM's with twin scroll spool up quicker, etc.

What's the difference between the UK and the JDM, i.e where in the RPM range does boost begin on both models?
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Old Mar 19, 2015 | 01:03 PM
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Not as much difference as your led to believe. personally from owning both. is it worth the price difference between the cars prob not,

your talking less than 1000 rpm difference
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Old Mar 19, 2015 | 01:06 PM
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Originally Posted by cuprajake
Not as much difference as your led to believe. personally from owning both. is it worth the price difference between the cars prob not,

your talking less than 1000 rpm difference
Well, the JDM is about more than twin scroll to be fair, i test drove numerous examples of both before buying a JDM and have to say it feels a different car altogether.

Do you know the actual figure as to where boost kicks in for both cars?
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Old Mar 19, 2015 | 01:40 PM
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off top of my head id say

jdm 2800
uk 3500

there abouts anyway, its a different type of delivery though the jdm is more linear

having had a spec c, and uk cars id say the 2.5 hawk drove very similar to the jdm
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Old Mar 19, 2015 | 01:46 PM
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Originally Posted by cuprajake
off top of my head id say

jdm 2800
uk 3500

there abouts anyway, its a different type of delivery though the jdm is more linear

having had a spec c, and uk cars id say the 2.5 hawk drove very similar to the jdm
Cheers mate.

As far as the UK Hawk and JDM Hawk, IMO they are night and day difference, but obviously that's as i say IMO.

The UK hawk runs out of puff like a diesel! Awaiting flaming
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Old Mar 19, 2015 | 01:50 PM
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Originally Posted by mestonian
Cheers mate.

As far as the UK Hawk and JDM Hawk, IMO they are night and day difference, but obviously that's as i say IMO.

The UK hawk runs out of puff like a diesel! Awaiting flaming
But you are comparing a 2.0 to a 2.5 that's in the u.k car.
The 2.0 is a much more revvy engine.

Its personal preference at the end of the day.
Some like the twin scroll linear power delivery
Others prefer the shove and burble of a single scroll
And others the torque of the 2.5
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Old Mar 19, 2015 | 01:51 PM
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Originally Posted by fat-thomas
Its personal preference at the end of the day.
Exactly.

What i was saying is the UK Hawk and JDM Hawk do not drive very similarly, in my opinion.

They're about as different as you could get. Ones got a big lump of torque low down and the other likes to scream.

Last edited by mestonian; Mar 19, 2015 at 01:53 PM.
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Old Mar 19, 2015 | 01:56 PM
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Originally Posted by mestonian
Exactly.

What i was saying is the UK Hawk and JDM Hawk do not drive very similarly, in my opinion.

They're about as different as you could get. Ones got a big lump of torque low down and the other likes to scream.
Because it has a totally different engine and gear ratios lol
I prefer the revvy 2.0 as it's not made of chocolate and can be tuned to pretty big bhp on standard internals
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Old Mar 19, 2015 | 02:11 PM
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Originally Posted by fat-thomas
Because it has a totally different engine and gear ratios lol
I prefer the revvy 2.0 as it's not made of chocolate and can be tuned to pretty big bhp on standard internals
where as a properly built 2.5 is a much better road engine,,,,

All joking aside i preferred the 2.5 to the 2.0. low down grunt is epic for road use.

450bhp 2.5 is prob as good as it gets for road
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Old Mar 19, 2015 | 02:12 PM
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Originally Posted by Tidgy
where as a properly built 2.5 is a much better road engine,,,,

All joking aside i preferred the 2.5 to the 2.0. low down grunt is epic for road use.

450bhp 2.5 is prob as good as it gets for road
Yes but we are talking out of the box engines here and the 2.5 is a turd until rebuilt correctly
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Old Mar 19, 2015 | 02:14 PM
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Originally Posted by fat-thomas
Yes but we are talking out of the box engines here and the 2.5 is a turd until rebuilt correctly
they do have reliability issues out the box, bit of a shame realy, but they don;t all let go though.

personaly i'd still take the hit on the extra cost to rebuild the 2.5 rather than run the 2.0 at 450. 2.5 will be half way down the road while the 2.0 is still trying to build boost,,,, lol
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Old Mar 19, 2015 | 02:16 PM
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As said before if you're waiting to build boost its because you are in the wrong gear and need to learn to drive
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Old Mar 19, 2015 | 02:19 PM
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Originally Posted by fat-thomas
As said before if you're waiting to build boost its because you are in the wrong gear and need to learn to drive
i don;t tend to drive round at 4.5k everywhere unlike you you SIOC wannabe,,,


by an interesting comparison the shorter ratio box in my R does seem to help with that end of things.
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Old Mar 19, 2015 | 02:20 PM
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Originally Posted by Tidgy
personaly i'd still take the hit on the extra cost to rebuild the 2.5 rather than run the 2.0 at 450. 2.5 will be half way down the road while the 2.0 is still trying to build boost,,,, lol
Rubbbisssshhhhh
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Old Mar 19, 2015 | 02:21 PM
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Originally Posted by mestonian
Rubbbisssshhhhh
lol, ok mr laggy, if it dont make 400ftlb by nigh on 4 grand i dont wanna know,,,,

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Old Mar 19, 2015 | 02:22 PM
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Old Mar 19, 2015 | 02:24 PM
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Originally Posted by Tidgy
i don;t tend to drive round at 4.5k everywhere unlike you you SIOC wannabe,,,


by an interesting comparison the shorter ratio box in my R does seem to help with that end of things.
On a series note,the lag thing is crap that's peddled by wrx tuning fantasists.
As long as you have a decent billet turbo and good supporting mods and map it's no issue and a splash of meth helps.

But 450 bhp is plenty for a road car in either 2.0 or 2.5
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Old Mar 19, 2015 | 02:24 PM
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Originally Posted by mestonian

ok i take it back, 415ftlb by 3700rpm


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Old Mar 19, 2015 | 02:27 PM
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Originally Posted by Tidgy
ok i take it back, 415ftlb by 3700rpm


lol, you're pretty when you're angry
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Old Mar 19, 2015 | 02:28 PM
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Originally Posted by mestonian
lol, you're pretty when you're angry
ooooooo you tease

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Old Mar 19, 2015 | 07:43 PM
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Originally Posted by Tidgy
they do have reliability issues out the box, bit of a shame realy, but they don;t all let go though.

personaly i'd still take the hit on the extra cost to rebuild the 2.5 rather than run the 2.0 at 450. 2.5 will be half way down the road while the 2.0 is still trying to build boost,,,, lol
Don`t agree with that, how can you say a 2.0 twinscroll turbo car is slow to get on boost!
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Old Mar 19, 2015 | 08:14 PM
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Originally Posted by Tidgy
ok i take it back, 415ftlb by 3700rpm




that's impressive..


what mods you running??


that's a classic impreza is it not?
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Old Mar 19, 2015 | 09:37 PM
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Originally Posted by Tidgy
lol, ok mr laggy, if it dont make 400ftlb by nigh on 4 grand i dont wanna know,,,,

So late? you should be able to hit 400lbft under that on a twinscroll
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Old Mar 20, 2015 | 09:03 AM
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Originally Posted by mickeymouse
that's impressive..


what mods you running??


that's a classic impreza is it not?

No my old car, hawk wrx with a forged 2.5 in the engine bay

mods list was

Forged pistons
uprated rods
2.5 open deck block
wrx single avcs heads
sti inlet manifold
perrin intake pipe
sti intercooler
full scr decat
700cc injectors
SC46+ turbo
ecutek map


Sold it an bought an M3, sold that and bought a type r
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Old Mar 20, 2015 | 09:04 AM
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Originally Posted by The Pink Ninja
So late? you should be able to hit 400lbft under that on a twinscroll
proof or its bs,,, lol

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Old Mar 25, 2015 | 01:18 PM
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I was getting 380ish @ 3650 on a VF36 on a standard 2.0l block, look at fellys graph
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Old Mar 25, 2015 | 03:00 PM
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I'm getting 395 lbft at 3700 rpm from my jdm with a vf37 decat and cosworth panel filter.
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Old Mar 25, 2015 | 03:33 PM
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Does the twinscroll offer a quicker 0-60 time/top speed over the single scroll? And do the JDM cars offer a quicker 0-60 time/top speed than the uk cars? Because these arguments may not mean that much either way?
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Old Mar 25, 2015 | 11:02 PM
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Fractionally they are faster yes but there is more to it than that, so much more drive able and responsive IMO
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Old Mar 25, 2015 | 11:54 PM
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Originally Posted by cuprajake
off top of my head id say

jdm 2800
uk 3500

there abouts anyway, its a different type of delivery though the jdm is more linear

having had a spec c, and uk cars id say the 2.5 hawk drove very similar to the jdm
The difference being that a 2.0 JDM can rev to 8k.

I've driven Glen's old S204 mapped by Bob Rawle and it absolutely flew from low down.
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