getting an RA gearbox fitted to my car and was wondering what sort of ratios these have and will there be a noticeable improvement in acceleration over my uk box, as im getting excited at getting the car back with the new box in

 

MY00 RA and my 5th gear is very similar to a UK 4th on my old MY98 turbo. About 20mph/1000rpm in 5th gear. I use 3rd where I use to use second to go round slow 90 degree corners. I just hope you dont do a lot motorway miles . Must be worth at least an extra 50bhp on aceleration and mid range.

 

RA gear ratios as follows;

1st 3.454, 2nd 2.333, 3rd 1.750, 4th 1.354, 5th 0.972

...enjoy!

 

If you are sticking with your UK engine then it is possibly a backwards step, you will be throwing gears at it and not have the RPM range to keep the speed in each gear. If you were dropping out of the power band on gearchanges and were prepared to lose economy, top speed and refinement then go for the closer stacked ratios. However, at less than 150-175 BHP/litre on most Subaru engines dropping out of the power band is not really an issue, and especially not on a TD04. Otherwise you might find your straight line times are slower.

 

chrisp

dont do many miles and hardly any on the motorway, was hoping the it would help me drive slower on the motorway as ill not sit at such high speeds,just checked out before it went to the garage and 80mhp is 3000rpm so ill have to have a laugh at what itll end up with th RA gearbox in, just out of curiousity what 0-60 times etc does your car achieve

 

john i have a tdo5 turbo sitting in my garage which i can pop on if needs be but thatll mean another tek3 remap and i was hoping to get away without doing it

 

Note that when Subaru do short ratios they usually also do:

STi bottom end and heads/cams for 8000 RPM rev limit
Larger turbo than the 7000 RPM models

All this is aimed at giving you a power band higher up the rev range which can be taken advantage of by shorter gearing, offsetting the usually meagre gains in torque.

This is why I think it is false that sometimes people compare the torque of a UK PPP with a shorter geared higher revving STi.

It is also why a 3.2 six with 8000 RPM and 100lbft less torque can rival a 4.9 eight with 7000 RPM and 100lbft more torque in gear with a modest weight advantage to the 3.2 (comparing M3 and M5 here). Also why a Civic Type R can embarrass torquier cars in the midrange.

Gearing has to go together with the power band to suit it, shorter gearing alone usually just means you spend more time changing gear.

To really make your gearing come alive, fit that TD05 Ideally with an STi engine. I know it is expensive, but that is where the real performance will come.

sg72's Type R is more impressive with the same turbo and similar torque/power that I had on my UK engine because of his combination of 8000 RPM rev limit and shorter gearing.

[Edited by john banks - 12/20/2003 8:38:56 PM]

 

john had the car R&R'd and the power drops off after 6500rpm so will it make a difference in the fact that mine will only rev to 7000rpm

if you were still doing the tek3's that tdo5 would of been on the car 3 months ago

[Edited by stevebt - 12/20/2003 8:46:51 PM]

 

Would still be more suited to the shorter gearing if you could maintain a similar top speed in each gear.

 

My scoob runs a VF29 turbo just over 1.2bar boost, turbo kicks at about 2,500rpm and flies all the way to 7,500 redline and doesnt feel like any drop off. On the RR max power was at 6,600 and max torque at 4,000rpm.

0-60 dont know never been timed heard off everything from 4.3 to 5.5. To get a good 0-60 I would have to go into the red zone in second. 0-100 is about 12 seconds and according the RR graph 103mph is 7,600 rpm in 4th gear.

[Edited by chrisp - 12/20/2003 9:07:57 PM]

 

roll on tuesday when i pick the car up then ill know if it was all worth itby the sounds of it im going to have to fit that tdo5

 

that td04 was fine steve, works ok, although its made my car flat as a fart higher up the rev range

sounds totaly diffrent from the ihi one that was on before, this ones like a dentists drill type whistle noise lol

the last one was like sum kind of wooshing hoovery suck thing (when it wasnt broke)

goimg to replace it with a td05 next year

 

Sorry to sqeeze-in on this thread, BUT, I am fitting an early RA trans to my STiV3, 4.11 diffs etc.
Today I'm trying to get the original STi rear diff out, but my half shafts do not have the usual split pins through the green CV's! Just how do you get the Shafts off the diff? I've removed the transverse link long bolt from the hubs to give pleanty of room to pull the h/shaft out, but all is solid after I take up the h/shaft float.
Any advice please?
Graham.

 

Job done, simple when someone tells you!
Wish Haynes would do a Manual...
Thanks for everyone's help!
Graham.

 

Is an RA gearbox stronger the the original gearbox?

Mike

 

Dont know if you've got time as the 5th Gear can be a real pain on along journey. Over 4000rpm in the summer can also bring the oil temp nearer 100deg.

When I have the cluch done on my TypeR (same box as RA) in the new year, I am having the UK 5th gear put in, which will raise the 4000rpm cruise from 80mph to 90mph. This is the same gearing as the V-Limited R/RA boxes.
Not a huge differeence but enough to make 85-90mph motorway journeys sustainable.

The first 4 gear remain the same which will get you over a ton very quickly.

 

BTW, its a simple procedure and the gear itself is only about £60 new and cheaper SH.

 

hol i wouldnt get the uk 5th put in as the person who is fitting my gearbox has tried that and if you boost the car thru all the gears the car dies in 5th and you have to wait for the car to build up againso you will have a 4 gear car with a seperate gear for motorways,

 

Somewhere else I think John Banks suggests an STi 5th is the better chioce, not so tall as the uk5th, and more in keeping with the RA gearset.
I'm not too bothered about motorway bashing as the car is realy for hill climbing, but I do drive it on the road for 3000 miles so will get buzzzzzed by the 5th, even the sti5th is short, busy at 80mph!
Sounds like an oil cooler is next...
Graham.

 

Isn't the point of the RA that you can get the best gear for the strongest accelleration using the Sti's biggest strength, turbo in at 3500 and there all the way to 8000? That's a lot of revs to run through. The stock STi ratio's are realy good for the road, and changing for the RA set should make it much stronger overall if you are up to country road blasting. I do serious hill climbing and you soon feel the gaps in the STi gears. 0-60 dashes are not realy the issue, though a great yardstick. Time between to pionts along a twisty road (or course)is the real measure?
God, I hope I'm right as converting the car to RA transmission is a long task!Mine has the 4.11 gears, sould be better? Is the RA box any better strength?
Graham.

 

I saw 110 degrees oil temp in the summer on the motorway ended up driving at 55mph to get the temp down

 

I have a STI RA v5 gear set.
5th is 0.825
not so short.
more easy to keep speed limit

 

chrisp your oil temp might creep up a few times but would you trade your acceration for something more subtle, i dont think so as then what would be the point of such a quick car