Gearbox options/experiences
09-25-2014, 12:01 PM
#401
Elite Member
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
None of those online retailers have them in stock either. They will have to get it shipped from the UK. Assuming Quaife actually has the gearset ready to ship today it will still be a while before you get it. I paid for mine in middle January and the first event I ran with it was the Wilmington Pro Solo in July.
And David is right. You need to order several hundred dollars worth of parts from MazdaComp($860) AND you will need to have the case Machined. On mine, buy the time I bought the gears, paid for shipping, ordered everything from MazdaComp and paid someone who is experienced installing Quaife gears in Miata gear boxes to do the machine work and install($560)...the total bill was $4,393.96
The Quaife install is not a "drop in" and IMHO it would be pretty stupid to put used shift forks which wear out VERY quickly, used syncro rings which wear and crack, used syncro springs which snap and used bearings out of a gear box which suffered a catastrophic failure like most all of yours have into a transmission you are building to last for several years.
I wouldn't let mine go for what David is asking for his....supply and demand..... I would be willing to bet David's is the only complete gear box WITH verifiable records as to the quality of the install....for sale in the US right now.
And David is right. You need to order several hundred dollars worth of parts from MazdaComp($860) AND you will need to have the case Machined. On mine, buy the time I bought the gears, paid for shipping, ordered everything from MazdaComp and paid someone who is experienced installing Quaife gears in Miata gear boxes to do the machine work and install($560)...the total bill was $4,393.96
The Quaife install is not a "drop in" and IMHO it would be pretty stupid to put used shift forks which wear out VERY quickly, used syncro rings which wear and crack, used syncro springs which snap and used bearings out of a gear box which suffered a catastrophic failure like most all of yours have into a transmission you are building to last for several years.
I wouldn't let mine go for what David is asking for his....supply and demand..... I would be willing to bet David's is the only complete gear box WITH verifiable records as to the quality of the install....for sale in the US right now.
Reply
0
0
09-25-2014, 12:26 PM
#402
Former Vendor
iTrader: (31)
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 15,442
Total Cats: 2,099
I'm going to jump down the T5 rabbit hole with the G-Force gearset that Steven linked to. With any luck I can get it into a car for <$3k and have a much stronger gearset than the Quaife. Win-win.
Reply
1
1
09-25-2014, 01:28 PM
#404
Elite Member
Join Date: May 2008
Location: Canada
Posts: 1,981
Total Cats: 2,224
Most of what can be seen in your pics is the coasting side of the teeth. The arrow I've added points to the drive side, and it looks pretty rough, at least in this glimpse. If the teeth on it look like this all the way around, and across, then that gear is iffy. It's a surface roughness that is making the gear engagement grabby as opposed to slippery, which is adding to the stress on the teeth. Do all of the gears look like that on he drive side? It is possible that only 4th looks like that, which helped lead to it failing.
Look for pitting as well. It will appear near the root of the tooth, and if there's more than a spot or two it will appear as a broken line of pits/dots across the width of the tooth.
I'd probably run the gearbox even if all the gears look a little smeared like that, but replace 4th as a set, not just the single one on the layshaft. And turn the power down a little, since you've already found the limit
Edit: What does your builder think about it? He's got a better feel for it than anyone else since it's on his bench.
Look for pitting as well. It will appear near the root of the tooth, and if there's more than a spot or two it will appear as a broken line of pits/dots across the width of the tooth.
I'd probably run the gearbox even if all the gears look a little smeared like that, but replace 4th as a set, not just the single one on the layshaft. And turn the power down a little, since you've already found the limit
Edit: What does your builder think about it? He's got a better feel for it than anyone else since it's on his bench.
I'll have to look into whether Quaife will sell individual gear pairs. If so, unless other problems are discovered, I'll likely rebuild it to resell. Yes, I'll definitely be turning down the boost for track days.
I was beginning to feel a little like Cassandra, since no-one (until now) said anything about that gearset option. Please keep us abreast of how it goes. Better still, develop a kit and I'll upgrade so that I can run "allofit".
Reply
0
0
09-25-2014, 01:36 PM
#405
Junior Member
Join Date: Mar 2012
Posts: 56
Total Cats: 9
If you're ECU can handle it why not trim the boost at peak torque in 4th - that's where it's weak so pulling the boost back at that point might be enough to save another box and still have all the go you need in the other gears….
Just a thought….
Just a thought….
Reply
0
0
09-25-2014, 05:36 PM
#415
Former Vendor
iTrader: (31)
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 15,442
Total Cats: 2,099
Parallel development. I'm parting with one of the race cars (Thumper) in order to fund a development car (NB2) for our upcoming parts. Stuff like an AEM Infinity-6 PnP setup and EFR cast manifold/downpipe. In order to highlight the Infinity's flex-fuel and traction control capabilities, I need a transmission that will cope with ~400wtq, so it makes sense. I bought a Quaife box when it appeared to be the only option on the market, but sold it when I parted Theseus out. Now that we know the Quaife boxes don't hold up, I have a distinct motivation to come up with something. I'm still doing research but it seems like a stock-case T5 with a G-Force gearset and adapter bits could be assembled for <$3k. There are case upgrades and a few other internal upgrades that may be worth doing but they do drive the price up a bit. I'll start with a stock 87-93 box, see if it breaks, and go from there.
Now, here ye, here ye, the only words I've spoken publicly about turbo kits in months:
I have renderings of the manifold, a few people at MRLS saw them. Typical response was "Holy ****." SLA protos are pending. There is progress but I've been extremely tight-lipped because everyone wants to know "when" and I just don't have a good answer for that question. I'm not saying/showing **** until I have a better idea of when the foundry will have parts done for us. No timeline because I want them to be done correctly and still be affordable. I could have put a $1200 tubular version on the market 8 months ago, but I'm not a stupid man.
Now, here ye, here ye, the only words I've spoken publicly about turbo kits in months:
I have renderings of the manifold, a few people at MRLS saw them. Typical response was "Holy ****." SLA protos are pending. There is progress but I've been extremely tight-lipped because everyone wants to know "when" and I just don't have a good answer for that question. I'm not saying/showing **** until I have a better idea of when the foundry will have parts done for us. No timeline because I want them to be done correctly and still be affordable. I could have put a $1200 tubular version on the market 8 months ago, but I'm not a stupid man.
Last edited by Savington; 09-25-2014 at 05:46 PM.
Reply
0
0
09-25-2014, 06:36 PM
#416
Elite Member
Join Date: May 2008
Location: Canada
Posts: 1,981
Total Cats: 2,224
Most of what can be seen in your pics is the coasting side of the teeth. The arrow I've added points to the drive side, and it looks pretty rough, at least in this glimpse. If the teeth on it look like this all the way around, and across, then that gear is iffy. It's a surface roughness that is making the gear engagement grabby as opposed to slippery, which is adding to the stress on the teeth. Do all of the gears look like that on he drive side? It is possible that only 4th looks like that, which helped lead to it failing.
Look for pitting as well. It will appear near the root of the tooth, and if there's more than a spot or two it will appear as a broken line of pits/dots across the width of the tooth.
Look for pitting as well. It will appear near the root of the tooth, and if there's more than a spot or two it will appear as a broken line of pits/dots across the width of the tooth.
Any further thoughts/observations?
Reply
0
0
09-25-2014, 09:08 PM
#417
I toy with the idea of bumping up the power on my car but I have to ask at what power level do 6 speeds become a problem? Is it just the turbo guys with the massive torque hit or do the SC guys have issues too?
Most feel stock rods are good for 250tq. Is the same true for the 6 speed?
Most feel stock rods are good for 250tq. Is the same true for the 6 speed?
Reply
0
0
09-25-2014, 10:41 PM
#419
I toy with the idea of bumping up the power on my car but I have to ask at what power level do 6 speeds become a problem? Is it just the turbo guys with the massive torque hit or do the SC guys have issues too?
Most feel stock rods are good for 250tq. Is the same true for the 6 speed?
Most feel stock rods are good for 250tq. Is the same true for the 6 speed?
Bob, what's your histogram or tq vs life?
__________________
Reply
1
1
09-25-2014, 10:57 PM
#420
Elite Member
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
That's not 4th that's the primary drive gear set that broke. Drives the secondary shaft and every gear except 4th. 4th gear in the 5 speed just locks the input and output shaft together so no load actually goes through any gear teeth at all in 4th for a 1:1 ratio and the secondary shaft just spins freely with no drive load. Cant break 4th. The six speed does that in 5th.
Reply
0
0
