Gearbox options/experiences
#310
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And if you do...don't skimp on having it built. Replace every single wear item in the donor box (@$650) and have a shop that knows what they are doing build it.
All of the Quaife failures I have seen had "issues" which could have been related to the install. It's not a drop in install. I've built several motors, transmissions, rear ends and was a jet engine mechanic in the US Air Force.....and I still coughed up the dough to have a pro build the box.
After you have spent 3500 in parts...what's an extra $500 to have the case machined properly and have everything set up buy someone who has built a few thousand Miata transmissions?
And before you say $4 grand....that's just too much money. Think about people who have broken 7 5 speeds and 4 6 speeds. If you assume $250 for the 5 speeds and $600 for the 6 speeds you have already spent $4,150 on stock boxes, had to change transmissions 11 times and missed at least part of an event.
Kinda ashamed I didn't do it sooner.
All of the Quaife failures I have seen had "issues" which could have been related to the install. It's not a drop in install. I've built several motors, transmissions, rear ends and was a jet engine mechanic in the US Air Force.....and I still coughed up the dough to have a pro build the box.
After you have spent 3500 in parts...what's an extra $500 to have the case machined properly and have everything set up buy someone who has built a few thousand Miata transmissions?
And before you say $4 grand....that's just too much money. Think about people who have broken 7 5 speeds and 4 6 speeds. If you assume $250 for the 5 speeds and $600 for the 6 speeds you have already spent $4,150 on stock boxes, had to change transmissions 11 times and missed at least part of an event.
Kinda ashamed I didn't do it sooner.
#311
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Problem is a really usible ideal autocross gear is too low for even the slow corners on most every track I run.
And I also think the best SSM autocross box would be a Nascar 3 speed dog box. as a side benifit it would be about 20lbs lighter than the Mazda 5 speed I think.
#312
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Why not save even more weight with a 52lb Jericho 2 speed. Just gear it to 74 with the 4.10, and keep a setup 4.30 for tighter courses. Its 18lbs lighter than the 3 speed and 20 pounds lighter than the 4 speed. And I think once you put the bell housing on the 4 speed it'll be in between the weight of the miata 5 and 6s. But they're all side loader boxes which are going to have exhaust clearance problems.
#316
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Helios did mine. While ISC is MORE than capable of building a stock box, I would not send them a Quaife set because they haven't done one before. There is some machine work which has to happen to the case...and no mention of the a chine work is in the instructions that come with the gear set. I would send it only to someone, who when you talk to them, mentions the machine work to the case BEFORE you bring it up. That way you will know they know what they are doing.
#317
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Why not save even more weight with a 52lb Jericho 2 speed. Just gear it to 74 with the 4.10, and keep a setup 4.30 for tighter courses. Its 18lbs lighter than the 3 speed and 20 pounds lighter than the 4 speed. And I think once you put the bell housing on the 4 speed it'll be in between the weight of the miata 5 and 6s. But they're all side loader boxes which are going to have exhaust clearance problems.
#319
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Have you all actually laid hands on that quicktime bellhousing for the BP? That thing is made out of led. My current trans is lighter than the T101A and that Bellhousing was. Just saying....Ive had both setups on the scales.
#320
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I could get on board with it, the rating and that there have been failures worry me. I would have a conniption fit if it broke after all that because then it would have made more sense to go all in on a $8k custom whatever else we're looking at.
In my case a tko600 with a .82 5th was brought to my attention and wouldn't be the worst thing in the world though there's a lot of fabrication involved compared to what I want to do (none), but zero worries about power.