R25 5-spd revs per km/h

deja vu 25

deja vu 25

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Fellow Frogger
Joined
Jan 22, 2002
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Location
Canberra
Hi All

Now I have a UN1 'box in my R25, I would be curious to know what RPM an R25 with A UN1 box at 100km/h is doing, and also one with the later NG3 'box?

Haakon???

Anybody else?

I have found that my R25 seems to be jst on 3000rpm at 100 clicks, which is not far from the 3 spd auto.

I too, have finally realised what people talk about when they say Fuego's have a great amount of torque! Gee 5 gears makes a difference - A totally different car, and much more economical too. I have manage 8 l/100kms in normal city driving!!
Maybe the auto EFI computer runs leaner???
 
Hi Luke. Pretty sure my NG manual box runs at around 2700 rpm at 100 kph. This is always assuming the speedo and tacho on that car are accurate. I only ever drove it the once, to get it from Bendigo to my parents place in Castlemaine (on the plates from my auto - sorry Mistareno :whistle: ).

Compared to the auto, it goes like stink (drives like a smoother, bigger Fuego) and did feel a whole lot more relaxed on the highway.

I have already stripped out the manual conversion from this car, so I cant take it for a spin to confirm the revs, and with my auto miracuously ressurecting itself I may not know for a while. :rolleyes:

What the workshop manual have to say about ratios of UN Vs NG?
 
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Here you go Luke, assuming a 0.82 5th gear and a 3.89 Final on standard tyres as per specs I found on the UN1 fitted to the R25 GTX, 3000 rpm should see
109 kph.
According to specs for the NG3 in my Fuego manual (and assuming the R25 NG3 is the same), I will be doing 118 kph at 3000 rpm. I think I just found an argument for the NG :D

This is using this handy calculator

http://pw1.netcom.com/~sgalaba/mph.htm#gearspeeddata
 
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Hey Haakon,
I love that calculator - well done. :dance:
Yes, I thought the car revved a bit higher than I expected - not worried though, as the car is still magic :headbang:
When I get my R25 manual (book) back from the guys who did the conversion, I will check the drive ratios on the NG and UN1's and run the calculation.

As you say, that may be one point for the NG3 'box. Does that mean the actual 'box has taller gearing right through the gear range? ie it wouldn't be as quick off the mark? I know the original tests had the R25 leaded GTX at 0-100km/h in 10.3 secs vs 10.7 for the Fuego :whip:

Thanks again
 
R25 rpm

We drove back from Sydney cbd this evening on the airport freeway.
In this R25 an original 5 spd manual late 85, the tacho was 2300 on 100km/h.
But then again I have 15 inch not 14 inch wheels on it.


Chris
 
Hmmm. I'm wondering whose speedo is telling the biggest fibs out of our 3?
 
Haakon said:
Hmmm. I'm wondering whose speedo is telling the biggest fibs out of our 3?
Click to expand...

Thanks guys for your comments - much appreciated

Yes this just doesn't make sense. My gearbox is definately out of a 1985 R25 (Aust import), and it definately sits on 3000rpm - the engine noise sounds as if it is at this rpm too. :blush:

I know Haakon and myself had very similar readings when comparing our 3 spd autos at 100km/h.

I am confused - can anyone shed any light on this?

Is it possible that there is a UN1 with a different final drive ratio or something?
 
LukeCass said:
Thanks guys for your comments - much appreciated

Yes this just doesn't make sense. My gearbox is definately out of a 1985 R25 (Aust import), and it definately sits on 3000rpm - the engine noise sounds as if it is at this rpm too. :blush:

I know Haakon and myself had very similar readings when comparing our 3 spd autos at 100km/h.

I am confused - can anyone shed any light on this?

Is it possible that there is a UN1 with a different final drive ratio or something?
Click to expand...


PS - I also have 15 inch alloys on my car
 
R25 5 spd revs

OK - the first question I have is why am I being referred to as a tadpole?

Additionally - I remember my first R25 which was an '85 auto to manual conversion, also only ran at about 2200 - 2300 rpm at 100 kmh. The difference in the 2 cars is quite noticeable like the auto convert car really dropped the revs from 4th to 5th. Sometimes it used to slip out of 5th gear to neutral as one was cruising down the hwy. ( I still have the first one in a shed waiting for a paint makeover one day!)

Anyway both such nice driving cars - just that bit sportier than the cits that i usually get to drive.

But no complaints a lovely DS and a Cx Prestige!

chris
 
Tadpole? Your convert car - was it a NG from a Fuego, or an UN1?

Luke, did you get your manual back yet?
 
This is what I found on UN boxes

Model Part No. Ist 2nd 3rd 4th 5th Rev Diff
20 369.00 3.36 2.06 1.38 1.06 0.82 3.55 4.11
369.05 3.36 2.06 1.38 1.06 0.82 3.55 4.11
20TX 369 3.36 2.06 1.38 1.06 0.87 3.55 3.778
20LS/TS 369 3.82 2.18 1.41 1.03 0.86 3.55 3.778
21Turbo UN1-013 3.36 2.05 1.38 1.03 0.82 3.54 3.44
25GTX UN 1-03 3.36 2.05 1.38 1.04 0.82 3.55 3.89
25V6 UN 1-04 3.36 2.05 1.38 0.96 0.76 3.55 3.89
Alpine GTA UN1-05 3.36 2.05 1.38 1.04 0.82 3.55 3.44
25 Blindee UN 1-06 3.36 2.05 1.38 0.96 0.76 3.55 4.11
Alpine Turbo UN1-07 3.36 2.05 1.38 0.96 0.76 3.55 3.44
25V6 Turbo UN1-08 3.36 2.05 1.38 0.96 0.76 3.55 3.778
30TX 369-01/06/017 3.36 2.05 1.38 1.06 0.82 3.55 3.89
30TS 369-01/06/014 3.36 2.05 1.38 1.06 0.82 3.55 3.89

2300 rpm at 100 kph is right for a V6 box. :confused:. 1st to 3rd and final drive are the same b/w V6 and GTX, with a taller 4th and 5th.
 
Hmm, very interesting to read Haakon.

No I haven't got my manual back yet.

Next question would be to ask tadpole what UN1 type he has on his car. I will have a look at mine and see if it is the GTX number.
 
ar25 5 spd

I will hava a look on the weekend.
I havethe company workshop manual and ai knwo that it tells me who to identify in there. Will let you know.

ps I may be in Canberra on Saturday

chris
 
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