6 Speed Conversion???
#2
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this conversion has been discussed many times at miata.net. check there--and note that those who have done it don't just report negative gains in acceleration, but also rev more on the highway. I don't see any upside.
#3
there are plenty of upsides.
1) 6speeds are sexy.
2) if you pair a 6 speed to a 4.3 rear end, then your gearing will be a lot shorter, making for a quicker accelerating car. Good for touge and city driving but high revs for freeways.
Other than the tranny, you'll need the shift lever, and a 6spd ****. Also you'll need the plate that goes between the block and tranny. don't forget tranny fluid. While you're at it, might as well swap out your rear main seal on the engine, the front and rear seals on the tranny and put in a new clutch.
1) 6speeds are sexy.
2) if you pair a 6 speed to a 4.3 rear end, then your gearing will be a lot shorter, making for a quicker accelerating car. Good for touge and city driving but high revs for freeways.
Other than the tranny, you'll need the shift lever, and a 6spd ****. Also you'll need the plate that goes between the block and tranny. don't forget tranny fluid. While you're at it, might as well swap out your rear main seal on the engine, the front and rear seals on the tranny and put in a new clutch.
#6
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yes, they do seem to be stronger; I have not heard of the 6 failing under high power, but bear in mind that there are hundreds of 5 speeds for every 6, so not much of a sample exists.
I am yet to see a 0-60 or 1/4 mile time improve after the conversion. I have seen them go down. there is nothing sexy about spending lots of time and money to lose performance, shift more and buzz on the highway.
if you have any contradicting data to share, please do so.
I am yet to see a 0-60 or 1/4 mile time improve after the conversion. I have seen them go down. there is nothing sexy about spending lots of time and money to lose performance, shift more and buzz on the highway.
if you have any contradicting data to share, please do so.
#7
Well, if you were smart, you'd part the 6-speed with a 3.3, 3.6 or 3.9 rear-end. Which is exactly what many of the folks who've done the swap do. Kags1969 is running a 3.6 rear with his and loves it, from what I recall.
In fact, with the 3.6 and 6-speed, all the gear ratios will provid roughly the same speed potential as the 5-speed paired with the 4.3, except that 6th gear is now a bona fide cruising gear: 80mph is only 3600 vs. 4150 rpm for the 5-speed.
So, maintains great gear ratios, has true "gas-sipper" gear, is far stronger...what's not to like? Well, the price I suppose...
In fact, with the 3.6 and 6-speed, all the gear ratios will provid roughly the same speed potential as the 5-speed paired with the 4.3, except that 6th gear is now a bona fide cruising gear: 80mph is only 3600 vs. 4150 rpm for the 5-speed.
So, maintains great gear ratios, has true "gas-sipper" gear, is far stronger...what's not to like? Well, the price I suppose...
#9
You should ask Kags. I know there's a least one U.S. vendor that sells them. They came on the '79-'82 626 and the '01+ 6-speed Miata in Australia.
www.solomiata.com
And search M.net, as I don't believe he's the only one running a 3.6.
Edit: Okay, that was pretty quick; I just used the search button on M.net: http://forum.miata.net/vb/showthread...6+differential You can get them from Mazda Motorsports.
www.solomiata.com
And search M.net, as I don't believe he's the only one running a 3.6.
Edit: Okay, that was pretty quick; I just used the search button on M.net: http://forum.miata.net/vb/showthread...6+differential You can get them from Mazda Motorsports.
#11
Sure it's stronger, but what kind of power are you running. It only really makes sense if you're going with a lower overall final drive and can get the revs down to make better use of the new power... basically what Bripab said.
It's cooler granted... but again, but unless you're talking about 400hp and want a road burner vice a street car, it just doesn't make sense to me. Somebody may say something to convince me otherwise, but for the price...
#17
I believe the 6-speed couple with a 3.6 rear-end will give almost the same mph-per-gear in the first 5 gears as the 5-speed with a 4.3 but with a taller 6th gear for cruising.
Courtesy of Savington:
Assuming a 7000rpm redline and 22.7" tire diameter, here are some of the speeds you're looking at.
Your current ratios (5-speed, 4.3 final drive)
33.1 in 1st
58.2 in 2nd
82.7 in 3rd
109.9 in 4th
135 in 5th (3371rpm @ 65mph, 3889rpm @ 75mph)
6-speed with 3.636 final
34.6 in 1st
57.3 in 2nd
79 in 3rd
103.4 in 4th
129.9 in 5th
154.1 in 6th (2952rpm @ 65mph, 3406rpm @ 75mph)
6-speed with 3.9 final drive
32.2 in 1st
53.4 in 2nd
73.7 in 3rd
96.4 in 4th
121.2 in 5th
143.7 in 6th (3166rpm @ 65mph, 3653rpm @ 75mph)
6-speed with 4.1
30.7 in 1st
50.8 in 2nd
70.1 in 3rd
91.7 in 4th
115.2 in 5th
136.7 in 6th (3328rpm @ 65mph, 3840rpm @ 75mph)
Oh yeah, plus the 6-speed holds together with 500+ horsepower on a Miata-sized vehicle...so, yeah, I don't see any downside at all, assuming you have a 3.6 or 3.3 rear-end.
Courtesy of Savington:
Assuming a 7000rpm redline and 22.7" tire diameter, here are some of the speeds you're looking at.
Your current ratios (5-speed, 4.3 final drive)
33.1 in 1st
58.2 in 2nd
82.7 in 3rd
109.9 in 4th
135 in 5th (3371rpm @ 65mph, 3889rpm @ 75mph)
6-speed with 3.636 final
34.6 in 1st
57.3 in 2nd
79 in 3rd
103.4 in 4th
129.9 in 5th
154.1 in 6th (2952rpm @ 65mph, 3406rpm @ 75mph)
6-speed with 3.9 final drive
32.2 in 1st
53.4 in 2nd
73.7 in 3rd
96.4 in 4th
121.2 in 5th
143.7 in 6th (3166rpm @ 65mph, 3653rpm @ 75mph)
6-speed with 4.1
30.7 in 1st
50.8 in 2nd
70.1 in 3rd
91.7 in 4th
115.2 in 5th
136.7 in 6th (3328rpm @ 65mph, 3840rpm @ 75mph)
Oh yeah, plus the 6-speed holds together with 500+ horsepower on a Miata-sized vehicle...so, yeah, I don't see any downside at all, assuming you have a 3.6 or 3.3 rear-end.
#19
I believe the 6-speed couple with a 3.6 rear-end will give almost the same mph-per-gear in the first 5 gears as the 5-speed with a 4.3 but with a taller 6th gear for cruising.
6-speed with 3.636 final
34.6 in 1st
57.3 in 2nd
79 in 3rd
103.4 in 4th
129.9 in 5th
154.1 in 6th (2952rpm @ 65mph, 3406rpm @ 75mph)
Oh yeah, plus the 6-speed holds together with 500+ horsepower on a Miata-sized vehicle...so, yeah, I don't see any downside at all, assuming you have a 3.6 or 3.3 rear-end.
6-speed with 3.636 final
34.6 in 1st
57.3 in 2nd
79 in 3rd
103.4 in 4th
129.9 in 5th
154.1 in 6th (2952rpm @ 65mph, 3406rpm @ 75mph)
Oh yeah, plus the 6-speed holds together with 500+ horsepower on a Miata-sized vehicle...so, yeah, I don't see any downside at all, assuming you have a 3.6 or 3.3 rear-end.
Mark