who will be the first to try putting the sti 6 speed tran in?

[Hiryu]

I'm looking at taller 6-speed gearing for an application with a car that's also lighter and more powerful than a stock STi... I've found a 'high speed' gearset (which I think is from the Forester?). I'm not sure if it's as strong or the difference would be noticeable enough?

http://www.rallispec.com/gea_syn_rstf145.html

1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 0.971 6th - 0.756 (2005 STi ratios)
1st - 3.636 2nd - 2.235 3rd - 1.521 4th - 1.137 5th - 0.891 6th - 0.707 (HighSpeed ratios)
1st - 0.000 2nd - 0.140 3rd - 0.240 4th - 0.209 5th - 0.080 6th - 0.049 difference
1st 0.00% 2nd 6.26% 3rd 15.78% 4th 18.18% 5th 8.98% 6th 6.93% percentage

Anyways, it might be something to look at-

[Grintch]

Yes, the STi gearing leaves something to be desired. I think Rallispec's "high speed" gearset is based on Legacy parts. You might want to ask them how the strength compares.

[StatGSR]

Yes, the STi gearing leaves something to be desired. I think Rallispec's "high speed" gearset is based on Legacy parts. You might want to ask them how the strength compares.

If you read what Rallispec actually says about that gear set you would see that the gears are actually from the JDM forester STI because of strength concerns with the legacy parts.


"Are these gears the same as the USDM Legacy Spec B? The ratios are the same but we actually developed this kit using part numbers from the JDM Forester STI model. We found the Forester gears to be slightly stronger plus we are able to use a 3rd/4th driven gear with an appropriate keyway width (Legacy Spec B and MY07 USDM STI use a narrow keyway design). The 5th/6th gear, however, was updated in the Japanese parts system to a narrow keyway design and we are unable to supply a wide keyway version with the kit. Therefore we supply a custom adapter keyway for the 5th/6th.

How do the gears differ from the MY2007+ STI models? The 2nd through 4th gears are basically the same (except the wide keyway 3rd/4th driven gear as discussed above). But the STI does not have the tall 5th and 6th gear ratios.

Can you supply just the 5th/6th long ratio gears for my 07+ STI? Yes, no problem. Contact us by email for the pricing.

How much does this kit raise the top speed in each gear? The top speed in each gear is raised 6% for 2nd gear, 16% in 3rd gear, 18% in 4th gear, 9% in 5th gear, and 7% in 6th gear. So, for example, in 6th gear if your current top speed is 175mph the new top speed would be 175*1.07 = 187mph.

Why is 2nd and 3rd gear synchros supplied in the kit? These synchros are required for proper fitment due to a change in the number of synchro friction cone tab holes (from 6 to 4)."

[Hiryu]

Yeah, I read that, and it sounds good for the most part...but they are selling it, too. I guess all but 5th and 6th are the same as the 2007+ STis, so those should be solid...I'm just not sure about 5th and 6th. They said they use the stronger Forester gears, but how do those compare to the usual STi gears? Then again, those usually don't need to be the strongest gears, either.

Ideally, I think I'd even like to go taller, but I'm not sure if anybody makes custom gearsets for these...

[Slatt]

I spoke with Joe at FFR today about my order and he mentioned that they have plans to offer straight-cut gears with taller ratios for the 6MT.

They will also develop something for the STi hubs/spindles. The hardtop, alas, is of course planned but not being developed yet. Heat/Vent will come before the hardtop.

[Hiryu]

I spoke with Joe at FFR today about my order and he mentioned that they have plans to offer straight-cut gears with taller ratios for the 6MT.

Interesting...Unfortunately I would have liked helical cut, but I'm guessing they'd be creating these for dragging or maybe even track duty?

[07FIREBLADE]

Also spoke with Joe. The 6sp is not going to be ready for another 6-8 months. Trying to work out the shifter, gear ratios and reverse lockout ring. Had to pull the trigger on waiting or building my 5sp. At this current timetable I just had to rebuild the tranny.

[nkw8181]

I decided to just go with the 5 speed for now as well. Can we say future upgrades anyone??

[Joe Scott]

I spoke with Joe at FFR today about my order and he mentioned that they have plans to offer straight-cut gears with taller ratios for the 6MT.

They will also develop something for the STi hubs/spindles. The hardtop, alas, is of course planned but not being developed yet. Heat/Vent will come before the hardtop.

I dont remember saying we are offering straight cut gears for the 6-gear? we are going to tear down our 6-speed and re-gear it for a better track response since we had major turbo lag in 6th. at that time, we will solidify all the 6-gear goodies that will be needed for the 2wd conversion swap. as of now, we are still sticking with the 5-gear as recommended, but will most likely be offering the 6-gear setup in 6-8 months.

Joe @FFR

[Slatt]

I dont remember saying we are offering straight cut gears for the 6-gear? we are going to tear down our 6-speed and re-gear it for a better track response since we had major turbo lag in 6th. at that time, we will solidify all the 6-gear goodies that will be needed for the 2wd conversion swap. as of now, we are still sticking with the 5-gear as recommended, but will most likely be offering the 6-gear setup in 6-8 months.

Joe @FFR

Hmm, my mistake, then. Sorry about that. Sometimes all I hear is dogs barking...

[Kurk818]

The 6speed installation posed another issue with installation. See the pics below. Any suggestions on how to go about modifying the frame? I have some ideas but wouldnt mind some input.

[Wayne Presley]

I do not believe you have to do any frame mods to put it in, maybe drill two new holes for the rear trans bracket.

[Kurk818]

The transmission mount bolts fit within their slots. The transmission oil pan bottoms out on the frame with approx 1.25" left to completely seat the transmission mount. The transmission mount bolts go through the slots to just barely be visible on the bottom end, maybe 3/16" from top of plate.

[Goldwing]

I would definitely suggest calling FFR, since they have a six speed in the R car now, and probably spent a little time on solid works to deal with frame strength issues. That said, just brainstorming as you asked?

It looks like those interfering bars are cantilevers to the rear tail of the frame. Cutting those for clearance look necessary, but rebuilding that strength sounds to me like a good idea. Again, just brainstorming here, cutting the "X" bars just enough to clear that oval area then welding on a steel plate to the bottom of the frame with a hole cut out for the protruding part of the tranny might be a solution. It would tie the pieces back together and share loading with the other frame members to compensate. I'd check torsional rigidity before starting at the tail. That idea might not help in that area, in which case, placing sister bars below the plate would probably stiffen it back up. If you used spacers to nudge the engine and tranny mounts up a little, that could minimize any cutting you have to do as well. Hope that helps at least a little, I'm not an engineer.

[Kurk818]

I would definitely suggest calling FFR, since they have a six speed in the R car now, and probably spent a little time on solid works to deal with frame strength issues. That said, just brainstorming as you asked?

It looks like those interfering bars are cantilevers to the rear tail of the frame. Cutting those for clearance look necessary, but rebuilding that strength sounds to me like a good idea. Again, just brainstorming here, cutting the "X" bars just enough to clear that oval area then welding on a steel plate to the bottom of the frame with a hole cut out for the protruding part of the tranny might be a solution. It would tie the pieces back together and share loading with the other frame members to compensate. I'd check torsional rigidity before starting at the tail. That idea might not help in that area, in which case, placing sister bars below the plate would probably stiffen it back up. If you used spacers to nudge the engine and tranny mounts up a little, that could minimize any cutting you have to do as well. Hope that helps at least a little, I'm not an engineer.

What you have suggested is exactly what i was thinking. I was looking at connecting the two points of the rear lateral links and also another at the cross point of the bracing. Additionally i would take a 1/8" steel plate with the cut out that matches the pan on the transmission.

I will call FFR and see what they did. Wayne, do you know what FFR did on their 6 speed?

[Kurk818]

This is what i ended up doing.

[STiPWRD]

nice weld job! I hope I can be as far along in 2 months

[Kurk818]

Rebuilt the axles today. The axle shaft provided by FFR are too small to suite the STI ends. With adjustable lateral links and the sti shafts only being approx 1/2" longer than the FFR provided ones, i made it work. Waiting on FFR for the shifter linakge for now.

[Scargo]

No concerns about too much negative rear camber from making room for that extra 1/2"? I guess you can always fab new upper mounts...
But, wider stance! Then flare the rear flares... oh the slippery slope!

[Kurk818]

Im not concerned at all actually. Im putting 10.5" wide rims with 295's in the back. I will be installing carbon fiber flares regardless.

No concerns about too much negative rear camber from making room for that extra 1/2"? I guess you can always fab new upper mounts...
But, wider stance! Then flare the rear flares... oh the slippery slope!

[sponaugle]

Rebuilt the axles today. The axle shaft provided by FFR are too small to suite the STI ends. With adjustable lateral links and the sti shafts only being approx 1/2" longer than the FFR provided ones, i made it work. Waiting on FFR for the shifter linakge for now.

I'm also using an STI donor car (06 STI with an EZ30R H6), and I have the adjustable links so I may try to use the STI axel shaft as well. What did you do in the front to attach the knuckle to the provided bracket (which is a bit to narrow)?

Jeff

[longislandwrx]

It has been determined if you have a newer kit, you can grind the welds on the new bracket, remove the spacers and it will bolt up to the sti knuckle.


the holes may need to be redrilled to get the correct geometry.

[sponaugle]

It has been determined if you have a newer kit, you can grind the welds on the new bracket, remove the spacers and it will bolt up to the sti knuckle.
the holes may need to be redrilled to get the correct geometry.

Excellent!

[Kurk818]

What he said...

It has been determined if you have a newer kit, you can grind the welds on the new bracket, remove the spacers and it will bolt up to the sti knuckle.


the holes may need to be redrilled to get the correct geometry.

[Kurk818]

Ive ordered the 2WD conversion coupler from FRR. Reverse lock out cable has been custom ordered. All that is left is customizing the provided shifter for the reverse lockout and the cable mounts for the transmission. Hopefully will have everything completed in the next couple weeks. Tackling electrical at the moment.

[Scargo]

Ive ordered the 2WD conversion coupler from FRR.

On 1-20 Joe Scott said "we will solidify all the 6-gear goodies that will be needed for the 2wd conversion swap. as of now, we are still sticking with the 5-gear as recommended, but will most likely be offering the 6-gear setup in 6-8 months."
You're saying some conversion parts are already available? I will be talking to Joe on Monday as I am two weeks away from my availability date for my R. I have STi rear suspension components, an OS Giken diff and a six speed for my kit. I'm hoping I can also get some conversion parts.

[Joe Scott]

Scargo, we have the 2wd conversion adapter for the 6-gear, however we do not have any instructions or any other the other parts. if you purchase the adapter, your honestly on your own for now on the install. once we have instructions and all of the parts is when we will start supporting the 6-gear Joe@FFRTECH

[Scargo]

Glad to see you're well enough to be on the internet.
RE, adapter plate: I'll take one!
****, I'm a tranny expert now. Got it all apart and cleaned. Hope I can get it back together...
BTW, when I ordered the six-speed seal set for the transaxle, I seemed to get the only one Subaru had it the US!

[Kurk818]

Received the 2WD conversion coupler. Great looking product. Just waiting on the reverse lock out cable.

[metalmaker12]

Scargo, we have the 2wd conversion adapter for the 6-gear, however we do not have any instructions or any other the other parts. if you purchase the adapter, your honestly on your own for now on the install. once we have instructions and all of the parts is when we will start supporting the 6-gear Joe@FFRTECH

So is the six supported yet

[longislandwrx]

I am interested to know the weight of 6mt once the DCCD and rear section are tossed. Keep us posted Kurk.

[Kurk818]

The biggest weight loss would be the final output shaft and associated gear at approx 8lbs. The DCCD doesnt loose much weight if any. The 2wd converter actually mounts within the DCCD so what is removed from the center diff gets replaced with the 2wd converter gear. The tail housing is a minimal loss as well.

I am interested to know the weight of 6mt once the DCCD and rear section are tossed. Keep us posted Kurk.

[Sgt.Gator]

Updates?

[Kurk818]

Ive been working on slimming down my wiring for a couple weeks when i get an opportunity to. The reverse lockout mechanism is complete which finishes off everything on the transmission side. Now all thats left is modifying the supplied shift with the reverse lockout tumbler and getting it bolted in. I hope that comes sooner than later.

[Sgt.Gator]

I'm trying to understand the 6 speed conversion so please bear with me...is there an issue with using the 6 speed mated to the FF supplied axles and WRX hubs? Or is it just that folks are trying to do a full STI conversion with the bigger STI hubs?

[Wayne Presley]

I'm trying to understand the 6 speed conversion so please bear with me...is there an issue with using the 6 speed mated to the FF supplied axles and WRX hubs? Or is it just that folks are trying to do a full STI conversion with the bigger STI hubs?

It's using the hubs that give an issue, but that is an axle issue

[STiPWRD]

I'm trying to understand the 6 speed conversion so please bear with me...is there an issue with using the 6 speed mated to the FF supplied axles and WRX hubs? Or is it just that folks are trying to do a full STI conversion with the bigger STI hubs?

I ran into this exact problem in the rear of the car. The FFR axles are designed to work with wrx cv joints and consequently the wrx hubs and 5 speed trans. The sti rear axles, hubs, and 6 speed trans use a higher spline count (wrx uses 24 splines and sti uses 27 splines). Check out the axle photos in Sponaugle's thread:

http://thefactoryfiveforum.com/showt...l=1#post158780

It may be possible to use the sti rear axle in place of the FFR axles (since they look to be the same length) but you'd need to also use the sti hubs and 6 speed trans.

[Scargo]

When I came across this article http://www.speedhunters.com/2015/05/...0-lotus-elise/ in the thread EJ20 in a Lotus I was struck by the flat plate on the back of their six-speed transaxle. How'd they do that? It's so much cleaner than the modified snout.
tranny plate_conversion.jpg

[Wayne Presley]

When I came across this article http://www.speedhunters.com/2015/05/...0-lotus-elise/ in the thread EJ20 in a Lotus I was struck by the flat plate on the back of their six-speed transaxle. How'd they do that? It's so much cleaner than the modified snout.
tranny plate_conversion.jpg

Because that is a 5 speed trans...

[Buzz Skyline]

Look at that crazy shifter linkage! (Now I kinda want my seat in the middle too.)