drb5

iTrader: (4)

I'm looking to find out what is really best...the classic STi 5 speed boxes or newage STi 6 speed boxes, with over 400 lbsft.

It's purely as a true comparison, while still considering the STi 6 speeder has not been about as long as the classic STi 5 speeders, it might show if the 6 speeder really is worth the extra money, before deciding to jump up to a gear kit.

If those who have had problems with their boxes, can explain what the main problem was, be it syncro's, forks, or gears themselves, remembering to include what car they own, how much torque, what box they are using and how long for.

I myself have an STi version 5 box, but as it is in need of a couple of syncro's, i'm wondering if i should not repair it and get an STi 6 speeder. I have my doubt's though, as they fetch such good money and AFAIK still have syncro problems.

If i could get a poll to come up, this would be a lot easier, if anyone can explain to me how???

TonyBurns

iTrader: (3)

The uk boxes (early versions) had cheap polythingy in them which knackered up i believe, the JDM boxes dont have this (brass?) but ive not known one of the gogs or syncros go on a 6 speed box, plus the casing is stronger and its nicer to change gears with

Tony

harvey

iTrader: (48)

The six speed is stronger than the STi 5/6 five speed but I ran well over 4oo ft/lbs on an STi 6 box for a couple of years with no problems other than the centre viscuous which I changed to DCCD.
Six speed gears are wider and casing has substantially more bracing which I suspect ensures there can be no flex so the shafts are held in position more rigidly.
You can fit a five speed gear set in a six speed casing.

stockcar

the main problem with the 6speed at the power your talking about will be the ratio's.................you'll generally find them too short

john banks

I had a selector fork bush problem on 5th gear in my 2004 UK 6MT Dave. The jump from 4th to 5th isn't nice on the UK six speed, but to be honest on a 2.5, none of the gears 1-4 are very good. Even on a medium torque 2.0 it is slowing you down as you're throwing gears at it.

The very latest UK 6MT (as on MY06 2.5) might be a good choice if the ££££ is right?

drb5

iTrader: (4)

Thanks guys.

I remember about the ratios, but i'd like to have a shot of them, before i go and cancel the option out, as it then means i'm stuck with the version 5 box, as i don't have the money for a gear kit.

I'm not really a driver for the B-roads....mainly if i'm travellig somewhere, i have a wee blat, so it might not bother me so much??

TonyBurns

iTrader: (3)

With 400+lbs of torque you can be a bit lazy with the 6 speed I usually am and my cars only got 356lbs (roughly) but some think its manic because its a 6 speed, personally I dont and having had a 5 speed turbo and now a 6 speed JDM, the ratio's are much nicer in the JDM and you dont get caught out of gear like you do in a turbo.

Tony

john banks

You have the same torque as a Type 25 in a Spec C with a panel filter and backbox Tony? It must be running some overboost...

400 lbft on a 2.5 with a typical 7000 rev limit gets through 4 gears in the first 8 seconds from launch I found. That is too manic, you are wasting a lot of acceleration time changing gear - I had 4mph faster terminal with a five speed box in the same spec.

If B-roads are a rare event it might not matter, just select a tall gear and use it, as long as the turbo isn't too big.

TonyBurns

iTrader: (3)

Nope, my car has always shown good torque figures John , even when she had low miles on her she was pushing 30-40lbs over the marked 290lbs and she's being doing this consistantly
Must just have a good un

Tony

David_Wallis

Dave,

Sell the box to someone who thinks an STI box will handle the power, if you drive it properly it wont last, especially up your neck of the woods.. Buy a PPG syncro and dont get fooled by false economy There are people local to me killing sti 5 / 6 boxes with only 400bhp and less torque. (2 litre engines)

The ratios are too short on the 6spd, but then at the price

I also killed a syncro in my box, but it wasnt expensive to have fixed.

I suppose it all depends whether you want a fit and forget solution.

David

harvey

iTrader: (48)

Which rollersTony?

Dave: If you want a drive of a Classic WRX with six speed, I can arrange that here. The car is only around 285 bhp.
You can also drive a five speed WRX, over 400 bhp, I will know how much next week-end, .738 fifth and 4.11 diffs.

TonyBurns

iTrader: (3)

Prosports Harvey, both their old and new ones, compared to some of the cars like the TSL 333 ones which were giving out 332lbs and the PPP'd cars giving slightly under-just over book figures i think its pretty much spot on

Tony

drb5

iTrader: (4)

Fit and forget solution would be perfect David, but aren't we talking another 1k on top of the 6 speeder price, plus fitting/building charges? You also know, as well as i do, that nothing is everlasting...which really puts a dampner on shelling out over 2.5k.

Might take you up on the offer Harvey, but i'll see what i can do up here first...maybe a shot in a brand new STi is on the cards.

JohnB, i was thinking maybe a Forced Performance Green or even Red turbo?

Do JDM 6 speeders get more money for them(if you can find them), than the UK alternative?

Granby

iTrader: (5)

Don't they do 2 types of gearset

911

Last year i had a go in Litchfield's Type c black demo car with Ian and another on board.
I was encouraged to drive it on the road hard. The 6 speeder (2 litre engine) had their kit on so about 330 lbf (?)
The ratios seem very 'RA' to me so a bit too short (on the road) but on the hill climb track that could work.
I might have a shot at an 03 MY box with dccd soon available, and I'm tempted.
This subject is a long debate but few say negative things about the 6 speeder other than ratio spacing and weight.

Granby:
Yes, 2 types (ish) (from what I have read on Zen's web site)

Semi helical cut with synchro or dog engagement Quiet and strong
Straight cut with synchro or dog engagement Noisey and a bit stronger

Graham.

Granby

iTrader: (5)

Cheers Graham

TonyBurns

iTrader: (3)

Its only 5th and 6th that are shorter in a JDM box, but they are not that short top end of about 170mph.

Tony

john banks

Dave, you should spool up a Green OKish, but even that on standard pistons and with Phase II heads I would suspect would be an engine killer, Red is getting big for a road car IMHO on a 2.5 with 7000 RPM limit for response and throttle adjustability etc.

Tony, what boost are you running at 356 lbft?

drb5

iTrader: (4)

Just planning ahead a bit, John. Just a new engine gasket set, stronger rods and ARP studs are left on my list of "lovely bits".

Think i'll phone Subaru tomorrow for a test drive....salvage yard phone numbers at the ready!

TonyBurns

iTrader: (3)

Dont know John, power is at 318bhp if thats any good to you but its the standard JDM Map and standard exhaust if that helps
I should add that when the multiplier dropped down to x8 it was still pushing just over 300lbs of torque and 282bhp, may give you some indication???

Tony

john banks

It takes a remap and breathing mods done well to get a typical 2.0 twin scroll JDM Scooby or Evo to the torque yours is doing with a backbox and panel filter. Mind you on the same car in the same spec I've seen a 20% difference in torque between rollers.

TonyBurns

iTrader: (3)

You should see what Richard Bulmer can get out of a twin scroll JDM torque wise John seen just over 400lb's with a full decat and filter with about 360bhp

Tony

David_Wallis

Dave,

UK / JDM should be around same money circa 1k - 1500.

forget the FP greens and reds.. not ideal IMHO.

Graham, that makes 4 types.. + various ratios.

David

911

David:
Yes, but just back from China so brain I think is still on the Virgin Flight..
You all know I'm thick, but what is/are 'FP Greens and Reds'?

From JB's #18 above must be a turbo 'grade'??

Be gentle, it took me 31 hours to get back to my house from Guang Zhou.

Graham

David_Wallis

Forced Performance Turbos.. not the best imho.. have a look at www.nasioc.com

David

drb5

iTrader: (4)

I thought they went for about 1500+ David? Is that including all the needed parts too, diff, prop and linkage?


What's up with the FP turbo's? I was wanting to stick to the standard position and felt these were the largest available..

drb5

iTrader: (4)

Anyone else has probs with their 6 or 5 speed's?

dowser

6mt synchros wear quickly if you fit the short shift too. Still works, just a bit notchy/clunky sometimes.

john banks

Tony, my Evo IX was claimed to be 394 lbft at 1.5 bar on 2.0 http://john824.fotopic.net/p28539236.html . Nonsense, didn't feel anything like it and turned out to be 330 lbft on more honest rollers without wild extrapolations to flywheel figures. It then took a bit more boost to get to 355 lbft, but there wasn't another 45 lbft in it, it might be running another 10 or so now, but it isn't 400 lbft. 395 lbft on the same dyno was what broke my PAR 5 speed in 3 weeks. Two completely different levels of torque, completely different level of accerlation, but the same readings. From this dyno, 403/395 in a classic was enough to get 121mph quarter terminals on road tyres on a six speed...

I think 400 lbft on Optimax on a 2.0 stock twin scroll turbo Evo or Scooby needs a *lot* of boost and IMHO excessively high cylinder pressures. I'm more inclined to believe that Bob's was optimised in the 360s lbft rather than that everyone else can get 400 lbft with hardly any boost. With torque readings from dynos I think you have to ask about the plausibility rather than jump on the highest figures.

And this is all relevant to the thread. One man's 400 lbft is not another's so you have to be careful on transmission recommendations. Someone went in T-uk's car at the weekend when it was detuned because of a UK 5MT to avoid breaking it, and we were three up. He said it was far and away faster than another car that was claimed to have similar performance figures. This did 12.1 quarters on a six speed at about 115mph or so, yet on this dyno it has barely broken 300 lbft.

drb5

iTrader: (4)

I see what your saying John. Didn't want to give an exact figure of torque as i have no idea where this engine might be sitting once i've strengthened it, due to turbo etc, so the box is the weak link right now...or it MIGHT be.

If i could get a list of people who have used an STi 5 speeder to over say 430lbsft without any more problems than if it were 320 lbsft, then i'd stick to it, but if the 6 speeder will have less problems in the long run, i'd consider it, even if the gears don't always suit.

God, when i had the RA, i reckoned the gearing was ballistic, but it was a long top gear that let it down. 120 mph top whack isn't great in the real world roads and this is maybe where the 6 speed could suit me.

How does the UK 6 speed(first 4 gears) compare to the JDM RA(first 4 gears)?