TII Tranny to N/A Diff?? No Problem!!
03-27-09, 08:39 PM
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TII Tranny to N/A Diff?? No Problem!!
Ok everyone, first thing: I love Mazdatrix, they are a great company for getting OEM parts at sometimes better-than-mazda prices. This thread is not trying to take away from mazdatrix's sales or say anything about their pricing, only to show ppl others options.
w/ that said, i kno that the question has been asked a ton of times on the issue of swapping a TII tranny while leaving an NA rear end. as its been well covered already, if you are putting a TII transmission on a car that is originally n/a (whether you are swapping just the tranny or the motor as well is regardless, and you should also kno that there are also several other items that need to be swapped to match the tranny as well) you have basically these options:
1) also put in a TII drive shaft and rear end (INCLUDING the half shafts). this is the most thorough and "proper" way, but many like myslef have already poured thousands into their projects and dont mind keeping their N/A differential, especially if its LSD and the cars a street car anyways.
2) buy and install one of the custom mazdatrix shafts found here: http://www.mazdatrix.com/g9.htm (10th item down, $288 + shipping new, OCCASIONALLY found used on the forums for about half that). these also have the added benefit of having replacable U-joints (i belive?)
3) Use an Auto shaft
option three has been debated and you will see posts/threads for and against its use all over this forum. i will tell you this from personal experience: they will work but are a few inches shorter than than perfect fit. short enough that most ppl (including myself, altho i did run like this for about the first week of motor break-in) will not want to run it as-is. it is often said that a spacer will solve the problem (which it will, as i ran one for about a month or two) but it is not without its flaws. first, if you dont have access to machining equipment and if you have it done right, it will be expensive. i got mine incredibly cheap since i have a machine shop connection that took some scrap left over from a previous job and made it work for me. otherwise, i called around and got quotes of a properly engineered one (at least 2" tall, 3.5"W x 3.5"L , with a ~2" hole bored down the middle for the differential flange bolt (terminology?) lip and four bolt holes) and was consistently quoted $250 to $300. second, it WILL create a balance issue on the shaft, which we all kno leads to premature u-joint failure. for these reasons, i looked into tossing the spacer and having my auto shaft modified and was greatly surprised. this leads me to my fourth option which is both cost effective and reliable. im sure there are others that have done this too.
4) buy a used auto shaft and have it lengthened!!!
while most driveshaft shops will tell you that nothing can be done for a shaft with non-replacable u-joints, i took my shaft to a local driveline shop my dad is familiar with and was amazed that they only charged me $85, count 'em EIGHTY-FIVE AMERICAN DOLLARS to lop both ends off, weld them to a new shaft of the correct length and then balance it. since i only spent $40 on the auto shaft (i assume this to be a pretty common price in our F/S section?) my total came up to $125, less than half the cost of the mazdatrix unit BEFORE shipping. the guy said it would have been thirty dollars less had my NA shaft had the same tubing as the auto since they wouldve have to only do the yoke end and not have to charge for the tubing!
anyways, like i said, im sure others have done this, i just wanted to post this up since several local friends have already asked me details on this. i hope this will help some ppl looking to keep their n/a diff but not wanting to pay an extra $300 to complete their project.
BTW, call your local driveline shops before doing this as im sure prices vary at least somewhat throughout the country.
pic: Top= N/A 5 spd driveshaft
Bottom= lengthened automatic driveshaft
PERFECT FIT!!!
w/ that said, i kno that the question has been asked a ton of times on the issue of swapping a TII tranny while leaving an NA rear end. as its been well covered already, if you are putting a TII transmission on a car that is originally n/a (whether you are swapping just the tranny or the motor as well is regardless, and you should also kno that there are also several other items that need to be swapped to match the tranny as well) you have basically these options:
1) also put in a TII drive shaft and rear end (INCLUDING the half shafts). this is the most thorough and "proper" way, but many like myslef have already poured thousands into their projects and dont mind keeping their N/A differential, especially if its LSD and the cars a street car anyways.
2) buy and install one of the custom mazdatrix shafts found here: http://www.mazdatrix.com/g9.htm (10th item down, $288 + shipping new, OCCASIONALLY found used on the forums for about half that). these also have the added benefit of having replacable U-joints (i belive?)
3) Use an Auto shaft
option three has been debated and you will see posts/threads for and against its use all over this forum. i will tell you this from personal experience: they will work but are a few inches shorter than than perfect fit. short enough that most ppl (including myself, altho i did run like this for about the first week of motor break-in) will not want to run it as-is. it is often said that a spacer will solve the problem (which it will, as i ran one for about a month or two) but it is not without its flaws. first, if you dont have access to machining equipment and if you have it done right, it will be expensive. i got mine incredibly cheap since i have a machine shop connection that took some scrap left over from a previous job and made it work for me. otherwise, i called around and got quotes of a properly engineered one (at least 2" tall, 3.5"W x 3.5"L , with a ~2" hole bored down the middle for the differential flange bolt (terminology?) lip and four bolt holes) and was consistently quoted $250 to $300. second, it WILL create a balance issue on the shaft, which we all kno leads to premature u-joint failure. for these reasons, i looked into tossing the spacer and having my auto shaft modified and was greatly surprised. this leads me to my fourth option which is both cost effective and reliable. im sure there are others that have done this too.
4) buy a used auto shaft and have it lengthened!!!
while most driveshaft shops will tell you that nothing can be done for a shaft with non-replacable u-joints, i took my shaft to a local driveline shop my dad is familiar with and was amazed that they only charged me $85, count 'em EIGHTY-FIVE AMERICAN DOLLARS to lop both ends off, weld them to a new shaft of the correct length and then balance it. since i only spent $40 on the auto shaft (i assume this to be a pretty common price in our F/S section?) my total came up to $125, less than half the cost of the mazdatrix unit BEFORE shipping. the guy said it would have been thirty dollars less had my NA shaft had the same tubing as the auto since they wouldve have to only do the yoke end and not have to charge for the tubing!
anyways, like i said, im sure others have done this, i just wanted to post this up since several local friends have already asked me details on this. i hope this will help some ppl looking to keep their n/a diff but not wanting to pay an extra $300 to complete their project.
BTW, call your local driveline shops before doing this as im sure prices vary at least somewhat throughout the country.
pic: Top= N/A 5 spd driveshaft
Bottom= lengthened automatic driveshaft
PERFECT FIT!!!
03-29-09, 08:50 AM
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Project P --- Pedospeed
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yea, i was suprised out how good of a deal it was, in fact i wasnt even really considering this until my dad convinced me to just go and talk to the guys over and get a quote. thats why i wanted to post this so others could kno.
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