Higher 5th ratio - K8DE V6
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Oeps.. now I see Marco posted thesame information about that gear.
Anyways… There is a member here that has a big RPM drop when shifting from 4th to 5th...
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Approx figures from today's driving with .717 in a k8 gearbox.
60mph = 2700rpm
70mph = 3250rpmIt was never for performance for me. Boosting in 5th gear is a brilliant way destroy the gearbox! Drag racing is 1-4. So I went for the eco 5th gear, and it sets motorway cruising at the bottom of the powerband.
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Perfect! Where can I get a set of 0.717 gears?
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@8732510926=Stuz:
@8732510926=Ice:
Hi Marco, Where can I get a set of 0.717 gears.. also do I need to get just the gears or do I need to use matching synchro rings etc? PPs what does it drive like? must be a big drop from 4th to 5th! :shock:
Car / Engine MX-6 FS-DE & 626 FS-DE GearboxG25M-R
Gear Ratios (Input:Output)
1st 3.307:1
2nd 1.833:1
3rd 1.233:1
4th 0.914:1
5th 0.717:1
Final Drive 4.105:1The 0.717 can be found in the G25M-R I think you will need the syncro ring too so get it just incase. . .
@8732510926=Ice:
Perfect! Where can I get a set of 0.717 gears?
I will post it in a different colour for you. . . .
Car / Engine MX-6 FS-DE & 626 FS-DE GearboxG25M-R
Gear Ratios (Input:Output)
1st 3.307:1
2nd 1.833:1
3rd 1.233:1
4th 0.914:1
5th 0.717:1
Final Drive 4.105:1The 0.717 can be found in the G25M-R I think you will need the syncro ring too so get it just incase. . .
Stu
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Apologies, let me re-phrase that. I mean I have seen sets of new gears available ( but probably expensive) - do i need to break up a whole gearbox? Or can I get the parts from a specialist? Or is anyone on here selling a set?
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I bought both sets from clubprotege.com. Take a look in their for sale section. There was a guy had 3 sets a while ago, not sure if he has any left now.
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@e202738474=Ice:
Apologies, let me re-phrase that. I mean I have seen sets of new gears available ( but probably expensive) - do i need to break up a whole gearbox? Or can I get the parts from a specialist? Or is anyone on here selling a set?
I personally would pop down the scrapyard or try and get a gearbox from Ebay, Our scrap yard charges £40 +vat for a gearbox, I can't imagine others out there being much more expensive. . .
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I was thinking maybe get an mx6 / 626 or probe v6 box, swap the gears and sell it on as an unknown gearbox, or even as a special close ratio box! LOL… just a big thing to handle and my garage is kinda full. I mean rammed. I think ill wait until after the mot in may, unless s cheap box turns up locally..... the engine doesn't mind sitting at 4000 rpm. Doing 75...
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i used to do a weekly trip of 40 miles and its happy to cruise along at between 100-110mph. its a bit revvy but nice to be above the 2nd vris point so you know you still have power under your right foot. engine never missed a beat doing that at least once a week
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This is a very late addition to this thread, but I thought I'd put in my 2 cents worth (American) just for fun.
I recently swapped the entire internals from an FS engine (4cyl) 626 into my MX-3 gearbox. This got me a 4.11 final drive, different gear spacing, and a 0.717 5th gear. I now have 24mph/1000rpm in 5th - a huge difference. It's probably too tall a gear set for the K8, it just doesn't have enough low and mid-range torque. It is great for a KLxx 2.5 though. The reason the FS 4-cylinder would pull these gears is that it has its torque at much lower rpm than the K8. By the way, Probe GTs, at least American models, have the exact same gearbox as the MX-3, including final drive and 5th gear.
Transferring just the gears, without the final drive can be done, but requires more disassembly of both gearboxes to get the 4.39 pinion onto the new gears.
HOWEVER, the 5th gear only swap is easy, especially if you have an impact wrench to remove the nuts on the shafts. DON'T try to do this by jamming the small outer gear. You WILL break it! Trust me, this is from experience! Just take everything off of the FS box and swap it into the MX-3 box. Yes, you will have a big gap between 4th and 5th, but you should get 22mph/1000rpm or thereabouts, depending on tire size.
One more penny's worth. American driving conditions are radically different from those in the UK. I have taken my unmodified K8 MX-3 on several 500 mile trips, running an average of 80mph. Yes, the car did great, loved the revs, felt great, etc. BUT it is wearing on the ears to have such a buzzy, 4200rpm trip. The taller gears are MUCH nicer for long trips like this. If you're into café racing, then leave the standard MX-3 gearbox alone. It has great gearing for winding roads, lots of starts and stops. I STILL loved it after I put in the 2.5; 5th felt about like 3rd with the K8! But, the 2.5 engine is a torque motor and can use the longer gearing without giving up much, or any, acceleration.
