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Discussion Starter · #1 ·
Evening all,

Does anyone know if the top speed of the 123d is limited by revs/gearing?

I think it is quoted at 148mph in the brochure. Anyone achieved or exceeded this (on track/autoban of course!)?

Rich
 

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Most I hit was 140 mph. Think it could have gone a bit higher but I basically didn't have the balls to press on as it wasn't a straight-line private road either!
 

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Discussion Starter · #3 ·
Oh!

I don't think power is an issue on mine so will surely only be limited by gearing. I haven't been on the autoban to try though so I have only been up to 70mph.
 

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I've been flat out in one a few times.

The 123d does about 33mph per 1000rpm in 6th gear, so roughly 4.5k at 148mph.
It still has some revs left, but has no boost left at those revs, sufficient to beat the air back further.

It gains quickly to a point, then as you climb out of the midrange in 6th, gains are painfully slow.

It's not like V-Max in an NA petrol car, where power normally peaks near the red line!
 

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Discussion Starter · #6 ·
Thanks Red5,

So presumably a mapped car may go higher?

I've seen one with a stage 1 map storm up to about 130 with bags left to give.
 

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RMB123d said:
Thanks Red5,

So presumably a mapped car may go higher?

I've seen one with a stage 1 map storm up to about 130 with bags left to give.
I've seen quotes of approximately 6mph when stage 1 remapped whether or not that holds true remains to be seen given the wind resistance etc. as mentioned above but it's certainly believable
 

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Discussion Starter · #8 ·
Yeah, I'm sure it'll do 155 if the revs are there.
 

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I've had a shade under 150 in my 123 albeit I think I previous owner has mapped it(no proof... Yay) but yeah the revs do limit it, I felt when I got to them speeds it could carry on but was rapidly running out of revs, and balls lol. They can sit at 140 no problem at all, 150, just I would say!

Sent from my iPhone using Tapatalk
 

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The 123d is redlined at 5000rpm.

At 150mph, it still has 500rpm left, or to put it another way, enough revs to do about 16mph.

To go over the already slow to achieve 148mph, you'd need lots more power above 4500rpm, which even a remap won't get you!
So a bit of mapping is only likely to gain you a couple of mph.
 

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You'll be amazed how many cars fall way short of their claimed top speeds.

To get 150mph from 200 bhp in a hatch would be a real achievement.

The MK2 Focus claimed 163mph. During a few tests 145mph was more accurate.
 

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I've seen 155 on the speedo in remapped 120d (214bhp), I know it over reads on speedo, but maybe give you an idea, felt like there was maybe a little more to give, but maybe I'm optimistic :lol2:
 
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