just joined the turbo net
09-18-2018, 04:53 PM
#1
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just joined the turbo net
hey whats up just joined the forum and im sorry for the noob questions ive been trying to study and collect parts for a build and thought it was about time to join since im now getting into the real technical stuff, anyway thanks in advance for any help !
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09-18-2018, 05:17 PM
#3
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alright lol. here we go. sorry about the run on sentences its just not use to it since texting and all that has changed the way i type. anyway i have a 1991 mx5 with the 1.6L which is getting a 1.8 swap from a 95. the engine had good compression according to flyin miata which is who i bought it from. ive been looking for parts and slowly building the car. my end goal is to have 250hp to the wheels hopefully with a turbo build. ive decided on buying the fmii turbo kit without the turbo because i already bought a gt2560 off of someone. at the moment im trying to collect prts for the transmission swap. i just purchased a 6spd from a 2002 nb and it came with the flywheel and shifted an has all the bolts to it, or so it seems. and i know ill need a1.8 drive shaft and diff case for strength but i dont have those yet. right now the problem ive come across is what ill have to do for the speedometer since mine is mehanical and impretty sure the 2002 nb trans has an electric one. ivesearched and i think ive found some answer but what makes it even more complicated for me to understand is what is supposed to be done for the final drive speedo? my plan for the trans is to put a 3.6 diff in it and im reading that those are electronic unless im misunderstanding. so for the 6spd swap with a 3.6 final drive and a 1.8 engine how do you keep a mechanical speedo for the na cluster ? im sorry if this has been answered before (im sure it has) but im not exactly sure how to post or find threads for specific things. i usually just google and go from there. ive never been on a forum either so this is all new to me. and ive been searching lol. just not sure if im doing it right. thanks
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09-18-2018, 05:37 PM
#4
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Seriously, learn how to write properly, you'll find that people are much more willing to actually read your posts. It's hard to decipher a wall of text with no punctuation, no capital letters, no paragraph breaks, etc, and if you make your posts hard to read then people just skip them.
AFAIK, there is no simple drop-in solution for a 3.6 rear end with a mechanical speedo. Your choices are:
1) get a 3.6 VSS and do some surgery on it to try to hack it up into a gear that can drive the cable. I've heard of people trying this, but I don't know how feasible it is.
2) get a 3.6 VSS and an electronic-to-mechanical converter and use that to drive the speedo
3) get a 3.6 VSS and some kind of electronic display (retrofit NB cluster, race dash, etc)
4) GPS speedo
5) put in the 4.1 or 4.3 gear and learn to do the conversion in your head
--Ian
AFAIK, there is no simple drop-in solution for a 3.6 rear end with a mechanical speedo. Your choices are:
1) get a 3.6 VSS and do some surgery on it to try to hack it up into a gear that can drive the cable. I've heard of people trying this, but I don't know how feasible it is.
2) get a 3.6 VSS and an electronic-to-mechanical converter and use that to drive the speedo
3) get a 3.6 VSS and some kind of electronic display (retrofit NB cluster, race dash, etc)
4) GPS speedo
5) put in the 4.1 or 4.3 gear and learn to do the conversion in your head
--Ian
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09-18-2018, 06:08 PM
#5
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okay i see.
so would the more logical step to take for the 6spd be a 3.9 diff instead? i had just read everywhere that a 3.6 diff with a 6spd and turbo was a very good setup. if its not as simple as putting parts in then i may have to go with a different final drive.
so would the more logical step to take for the 6spd be a 3.9 diff instead? i had just read everywhere that a 3.6 diff with a 6spd and turbo was a very good setup. if its not as simple as putting parts in then i may have to go with a different final drive.
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09-18-2018, 06:23 PM
#6
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Search this way, using google: site:miataturbo.net xxxxxxx where x’s represent the words for which you are searching.
See how Ian enumerated his answers? That is a good format for your questions. We want you to win.
DNM
See how Ian enumerated his answers? That is a good format for your questions. We want you to win.
DNM
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09-18-2018, 08:36 PM
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Don't base your choice of rear end ratio on the speedo gears that are available. The speedo will work with the wrong gear installed, it'll just produce a number that's off by a certain percentage. For example, if you have the original 4.3:1 gear installed and install a 3.6:1 diff, then your speedometer is going to read about 20% (calculated as (4.3 - 3.6) / 3.6 low. So when it says you're doing 20 mph, you're actually doing 24, when it says you're doing 40 mph, you're actually doing 48, etc.
--Ian
--Ian
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09-18-2018, 08:54 PM
#9
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oh okay. i was really set on a 3.6 being that it made the 6th gear a real overdrive according to the research ive done. ive also read that a 3.6 diff is what japanese and australian cars had but would there be any specific vendor hanging out on here or maybe somewhere that you could point me to?
if i have to buy one from overseas then so be it, but ive seen miataroadster had a 3.6 ring and pinion for 700$.
as far as the diff itself goes ive wanted a 2way or 1.5 so i decided the kaaz or osgiken would be really good options
i guess in the grand scheme of things if my speedometer isnt 100% i wont really mind as long as it works and wont really need modification
if i have to buy one from overseas then so be it, but ive seen miataroadster had a 3.6 ring and pinion for 700$.
as far as the diff itself goes ive wanted a 2way or 1.5 so i decided the kaaz or osgiken would be really good options
i guess in the grand scheme of things if my speedometer isnt 100% i wont really mind as long as it works and wont really need modification
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09-19-2018, 12:15 AM
#11
A 6th option that Codrus didn't note is that you could get a custom gauge face made by Adam (revlimiter?) that would have the graduations at the correct rotational positions for the mis-matched sender/rear end ratio.
Eg: Install the 3.6 diff, don't change your sender, use a gps to note the actual speeds compared to the indicated speeds (or do the math) and then have a custom speedometer face made to match the actual speeds.
Eg: Install the 3.6 diff, don't change your sender, use a gps to note the actual speeds compared to the indicated speeds (or do the math) and then have a custom speedometer face made to match the actual speeds.
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09-19-2018, 01:04 AM
#12
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A 6th option that Codrus didn't note is that you could get a custom gauge face made by Adam (revlimiter?) that would have the graduations at the correct rotational positions for the mis-matched sender/rear end ratio.
Eg: Install the 3.6 diff, don't change your sender, use a gps to note the actual speeds compared to the indicated speeds (or do the math) and then have a custom speedometer face made to match the actual speeds.
Eg: Install the 3.6 diff, don't change your sender, use a gps to note the actual speeds compared to the indicated speeds (or do the math) and then have a custom speedometer face made to match the actual speeds.
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09-19-2018, 07:13 AM
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Thanks.
Rosa,
Use the same mechanical gear from the tail housing of the 5speed in the 6speed to drive the speedo cable. It will fit in place of the electric NB sender.
If I were you I'd just buy a 3.9 or 4.1 diff, axles, and driveshaft from a 1.8 car and not be concerned with a pricey gearset yet. And the differential you buy may already have limited slip. There is always time for fancy differential gears later but there are more important places for you to spend your money early on.
You will need a much stronger clutch than stock and better cooling system.
Suspension and brakes will also require upgrading. 1.6 cars had smaller brakes.
Rosa,
Use the same mechanical gear from the tail housing of the 5speed in the 6speed to drive the speedo cable. It will fit in place of the electric NB sender.
If I were you I'd just buy a 3.9 or 4.1 diff, axles, and driveshaft from a 1.8 car and not be concerned with a pricey gearset yet. And the differential you buy may already have limited slip. There is always time for fancy differential gears later but there are more important places for you to spend your money early on.
You will need a much stronger clutch than stock and better cooling system.
Suspension and brakes will also require upgrading. 1.6 cars had smaller brakes.
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09-19-2018, 01:23 PM
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gesso,
that seems like a good idea. its too bad i already purchased the zen gauges from revlimiter. :/
sixshooter,
i think a 3.9 would be the best option. ill just have to source the parts and stick with a 3.9 torsen for now. ive seen youtubers like gingium do that so itll probably be easier than the options that codrus provided.
as far as the clutch goes i decided on getting thr happy meal stage 1 from flyin miata when i get the money saved up. i just recently bought a roll bar and engine hoist so my pockets are a bit empty lol.
i really appreciate all the advise. one thing id like to know is exactly how much a 1.8L 3.9 torsen rear end should go for? ive seen some prices like around 1000. that seems like the average price but im unsure if there are cheaper ones laying around or if thats a pretty fair price .
that seems like a good idea. its too bad i already purchased the zen gauges from revlimiter. :/
sixshooter,
i think a 3.9 would be the best option. ill just have to source the parts and stick with a 3.9 torsen for now. ive seen youtubers like gingium do that so itll probably be easier than the options that codrus provided.
as far as the clutch goes i decided on getting thr happy meal stage 1 from flyin miata when i get the money saved up. i just recently bought a roll bar and engine hoist so my pockets are a bit empty lol.
i really appreciate all the advise. one thing id like to know is exactly how much a 1.8L 3.9 torsen rear end should go for? ive seen some prices like around 1000. that seems like the average price but im unsure if there are cheaper ones laying around or if thats a pretty fair price .
Last edited by rosaatomica; 09-19-2018 at 01:49 PM.
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09-21-2018, 01:27 AM
#16
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wow that sounds like a resllygood deal compared to what ive seen. ive checked ebay and the results havent been so good. i remember a while back 4.1 and 3.9 torsens were everywhere around here but now i cant seem them. i may just have to order from the uk or australia. or we could overnight parts from japan.
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09-21-2018, 01:51 AM
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The 3.9 was by luck as someone was breaking a car and I asked before they advertised. There seem to be a few 4.1 available in the UK on eBay but hit and miss regarding them coming with shafts.
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