As we all know as soon as you start to upgrade the power on a wrx the box tends to be the weak link
So it seems you have two options , upgrade to Sti or gear set swap ppg ect
Been speaking to a rally mate who's given me a couple of contacts , engineering company who does gear machining and another that's a gearbox rebuild specialist
Has anyone looked into having gear sets machined ( cost , design ect )
I think I'm gonna investigate when I get to that stage , or should I forget it and just do one of the normal options ?

 

Dare to be different, i'm sure you'll upset the apple cart again, as usual.

I'm interested to know what you find out and the costs involved, as i'm keen to keep both my 5 speed gearboxes.

 

Would be intrested to see if it's a cheaper option

 

Tbh guys I know very little about gearboxes apart I've changed the odd bearing
Im in engineering and know quite a few machine shops ( but not any gearbox specific ) apart from the contacts I've been given
Just seems natural to investigate the situation
Unless someone in the know has investigated before hand , difficulty , price
But I am a tightwad so if it's feasible the work would be mates rates

 

Think you will be best off with the basic options, try the scoobyclinic gearset, better than the PPG one.
If you also look at developement costs for the likes of gear sets it may put you off doing anything like that for life as it wont be cheap (a good 7 figure number if not more, a manufacturer has to put a gearset through hell so lots of R&D costs), but if you are good with CAD, understand different metal types, have a degree in astro physics and know how much torque each tooth can take on its own, go for it

Tony

 

Lol , I wouldn't imagine it's cheap , would a machineshop ( gear cutting ) not be able to look at the gears and think yeah you could use x material with x treatment process and machine it like x and basically copy it ( keeping standard ratios so as not to complicate things more )
I don't know tony at all , it's just a thought

 

Speak to Camcoat for friction reduction and resistance to wear, it's a type of ceramic coating they apply to the gears.

Also big In classic mini tuning, the guys running 300hp turbo A-series have been "Chryo treating" their straight cut gear sets with success. What this entails I don't know.

I havnt seen inside an impreza box, but one of the basic things to do, space permitting is to ally weld extra support beams near bearing supports and adding ribs to reduce movement of the casing.

Something to think about.

 

Mmm Interesting stuff there mate , I'm liking the ally stiffener idea , is this an impreza specific mod or general box mod ?

Also does anyone know What are the common weak points on the wrx box , which gears bearings ect

 

Not impreza specific but the basic principle can be practiced in any gearbox.

Reduce casing flex, improve bearing support, reduce friction. And on some cars with specific uses a transmision oil cooler can be beneficial.

 

Go for a STI box IMO. Pick one up for £1300 or there about's, I know Scooby spares offer an exchange and fit service which I'm hoping to do in the future.

 

Yeah I know the options and costs mate , whichever route I end up going I'll be fitting it myself regardless

It's just an idea and putting it out and seeing who's done what regarding gearbox mods or not , whichever the case maybe

 

Depends on your target

6 speed is good option,when prices of 6 speed dropping,I just hate on 6 speed gear ratios,which are too close for me,best 6 speed is from Hawkeye or from hatchback

We are run PPG at 490bhp,we will be running too on the 2.35L too PPG,we are like the long ratios(1st: 40mph,2nd: 74mph,3rd: 114mph,4th: 144mph and 5th: in theory 160mph),which is suit us like on the drag or track


Jura

 

i think for the fact that the 6 speed is proven time and time again and as you say jura getting cheaper all the time as well, would be a pretty safe option have seen a decent set up for for a grand, icant see you getting a better proven set up for less than that.
however possibly worth investigating as i am sure any info will be greatly appreciated by many members.

Grant

 

it all depends upon what goes in the box.

1. if you have a box that fails due to a gearset going fine upgrade the internals
2. if it fails due to a bearing failure most companies dont upgrade the bearings and so changing the gearsets wont solve the problem.
3. If it generally fails because of the synchro same as 2
4. If it generally fails becasue of the selectors same as 2.

Quiafe make great gearsets and so sometimes upgrade other components but generally they only do the gearsets...

it would be interesting to hear about the boxes of the subaru...if anyone knows,,,just what power they will take,...

std box
wrx box
sti box
newage box
6 speed box etc etc...