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Old 07-17-2015, 03:04 PM   #81
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new and improved because your car ACTUALLY runs, so it's a compliment.

he was very entertaining when he wasn't drunk posting
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Old 07-17-2015, 03:07 PM   #82
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I've seen his posts. Looks like a fun guy. Does he still have his Miata? Just gave up on it?
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Old 07-17-2015, 09:59 PM   #83
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Quote:
Originally Posted by Corky Bell View Post
A 6278 & a 6758. 45 in 5th is about 2200? And offers 2 psi. The 2860 matches that pretty easy, and the 2560 typically hits 4 at 2000 revs.

A VATN Aerocharger could be adjusted to make 10 psi at 1000, but it was undriveable. Best setting seemed like about 4 to 5 psi at 2k was good, but it was reluctant to make 200 rwhp.

Perhaps a 2860 and a VATN.............. I think I'll pass.

corky
Is the 2860 or the aerocharger that can make that boost down low also capable of 450hp?
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Old 07-19-2015, 08:44 AM   #84
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Is there a Miata transmission solution for 450hp at a reasonable price? Until such time, why would above 350hp matter?
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Old 07-19-2015, 01:05 PM   #85
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because then we can say we drive 450hp cars even though they've never been past 250
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Old 07-19-2015, 01:08 PM   #86
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Rx7 trans is pretty reasonable. Ratios just aren't good for road racing so it gets no attention here.
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Old 07-19-2015, 04:04 PM   #87
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How about just build a fast spooling 300rwhp 2560 setup? Compromises.
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Old 07-19-2015, 04:53 PM   #88
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Quote:
Originally Posted by aidandj View Post
Rx7 trans is pretty reasonable. Ratios just aren't good for road racing so it gets no attention here.
I need to look into this. With the SC it has plenty of torque, just needs longer spaced gears. A much taller 1st and 2nd would be great.
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Old 07-19-2015, 09:21 PM   #89
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The RX-7 Turbo transmission actually has decent ratios for road racing shifting @7,000 rpm gets you about 4,500 in 3rd (from 2nd) and around 5,000 anything above that except from 1st to 2nd which is low 4,000. Most turbo cars are making almost max boost in those ranges.
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Old 07-19-2015, 09:26 PM   #90
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Somewhere in the transmissions options thread the rx7 box is dismissed. Not sure why.
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Old 07-19-2015, 10:48 PM   #91
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Well depending on the amount of power you make (well torque), they can have issues with 3rd gear on track (north of ~300-350 ft.lbs.)
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Old 07-19-2015, 10:50 PM   #92
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What are you running for a trans?
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Old 07-20-2015, 02:06 PM   #93
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I currently have a RX-7 Turbo but most likely will switch is out for a dog-gear of some sort in the very near future as I know the turbo transmission will be on borrowed time pretty much right away!
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Old 07-20-2015, 08:14 PM   #94
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Quote:
Originally Posted by bcrx7 View Post
The RX-7 Turbo transmission actually has decent ratios for road racing shifting @7,000 rpm gets you about 4,500 in 3rd (from 2nd) and around 5,000 anything above that except from 1st to 2nd which is low 4,000. Most turbo cars are making almost max boost in those ranges.
Drop on shifts only really matters for drag racing. The issue when using it for road racing is that you're either too low in a gear or too high in a gear while in a corner.
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Old 07-21-2015, 12:15 AM   #95
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Quote:
Originally Posted by aidandj View Post
Somewhere in the transmissions options thread the rx7 box is dismissed. Not sure why.
Do you happen to remember the name of that thread? I searched for it but didn't find it. I've seen it before, and I believe someone (Sav maybe?) posted charts with the RPM drops for each gear for the RX7 and 5 and 6 speed miata transmissions. I wanted to go through that thread again.
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Old 07-21-2015, 12:46 AM   #96
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Gearbox options and experiences
<br />https://www.google.com/url?sa=t&sour...La1wvNJtMSqHZA
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Old 07-21-2015, 12:51 AM   #97
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Quote:
Originally Posted by Leafy View Post
Drop on shifts only really matters for drag racing. The issue when using it for road racing is that you're either too low in a gear or too high in a gear while in a corner.
You just shift then? But joking aside, the gearing is pretty standard compared to other 5 speeds. Sure if you have a 6 speed, then you have a close ratio. But I rather not drive a 6 speed on a road course, just too much shifting for my liking. Carry enough speed in the corner, then you won't be too low in a gear.
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Old 07-21-2015, 01:55 AM   #98
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Quote:
Originally Posted by aidandj View Post
Gearbox options and experiences
<br />https://www.google.com/url?sa=t&sour...La1wvNJtMSqHZA
Thank you sir!
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Old 07-21-2015, 02:51 AM   #99
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Quote:
Originally Posted by bcrx7 View Post
Carry enough speed in the corner, then you won't be too low in a gear.
Wildly oversimplified. Carry too much speed and you can't use the low gear, which forces you into the next higher gear. On a box like the Rx7 TII box, that means you're way, way down in the RPM range.
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Old 07-21-2015, 03:34 AM   #100
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Quote:
Originally Posted by aidandj View Post
Gearbox options and experiences
<br />https://www.google.com/url?sa=t&sour...La1wvNJtMSqHZA
Just read through that thread, thanks again.


Quote:
Originally Posted by bcrx7 View Post
Well depending on the amount of power you make (well torque), they can have issues with 3rd gear on track (north of ~300-350 ft.lbs.)
From poking around, I've found numbers thrown out of people racing cars with the TII transmission at 350whp reliably. Street cars with more.

Quote:
Originally Posted by Savington View Post
Wildly oversimplified. Carry too much speed and you can't use the low gear, which forces you into the next higher gear. On a box like the Rx7 TII box, that means you're way, way down in the RPM range.
I don't know crap about gearing as it applies to track use.

But I do have a question for anybody who has an opinion/experience: Is the RX7 TII transmision stronger than the Miata 6 speed? All other things aside, is it at least a stronger box? It seems that it is from my reading online.
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