erichwaslike Posted July 9, 2011 Report Share Posted July 9, 2011 pretty much as the title says, i want to source a fs5w71b(5speed) or a fs4w71b(4 speed) from a diesel 720. it needs to have the sd bell on it. i dont care if its 2wd or 4wd. it can also be blown up as long as the front case is intact. i got something tricky up my sleeve and need the case. let me know wat u have and wat u want for it or if u want to donate it in the name of research lol Link to comment
Master-O-Turbonics Posted July 10, 2011 Report Share Posted July 10, 2011 FS5W71B $200+ shipping. Trans has ~110,000 miles on it and shifts through the gears fine. area code is 30666 for shipping estimate (lucky number, I know) For an extra $75 I can pull the housings and media blast them. Sorry if the price seems high, BUT I also want a 5 speed kit for a roadster and that is what it'll take to pull it away from me. Link to comment
datzenmike Posted July 10, 2011 Report Share Posted July 10, 2011 The diesel only came with 5 speed and 2wd.You will need a mixture of different clutch arms/PP and release bearings to make your project work so take lots of pictures. Be sure to use a different 5 speed gear set, the diesel ratios are too wide like for a truck. 1st is way too low for a car. Link to comment
erichwaslike Posted July 11, 2011 Author Report Share Posted July 11, 2011 unfortunately that is a lil too much for wat im looking to spend on it.shipping wood be rediculous from ga to ca. thanks for the offer and if i cant find anything i may have to just bite the bullet. mike, i had planned to just use the front half of the diesel trans case and nothing else, no gears or anything. i was going to locate a short rear tailshaft trans and pop the front off and slide the diesel one on. that is the plan as of now let me know if u see anything wrong with that? Link to comment
datzenmike Posted July 11, 2011 Report Share Posted July 11, 2011 So you want a short FS5W71B 5 speed with diesel front. Yes that will work... Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 cool now to just find one local for free or cheap. id prefer one with a cracked rear case or something that makes it useless for the diesel and makes it really cheap Link to comment
ggzilla Posted July 12, 2011 Report Share Posted July 12, 2011 The SD bell pattern is the same as the U20? Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 the sd bell is the same as all the r,h,u series motors (r16, h16,18-19-20, u20) they share the same block. Link to comment
wayno Posted July 12, 2011 Report Share Posted July 12, 2011 unfortunately that is a lil too much for wat im looking to spend on it.shipping wood be rediculous from ga to ca. thanks for the offer and if i cant find anything i may have to just bite the bullet. mike, i had planned to just use the front half of the diesel trans case and nothing else, no gears or anything. i was going to locate a short rear tailshaft trans and pop the front off and slide the diesel one on. that is the plan as of now let me know if u see anything wrong with that? You will want to purchase a new lower cluster gear bearing for the diesel case, or take the diesel case to a machine shop and have them turn the lower bearing in the case for the bigger shortshaft transmission bearing, of course if you can find a 84-86 case it will already have the bigger bearing. I have already done what your planning on doing. I have been using 720 gasser transmissions behind my diesels for a long time now, I tow a lot, or did in the past, and I have not been able to tell the differance between them, 1st gear is the same as far as I can tell, the differance is the charteristics of the engine, a gas engine(L block) will rev to 5000 rpms, therefore you can get the speed up to 25 to 30 mph in first gear, but the diesel will only rev to 3000 rpm(it's worthless any higher even though redline is 4000 rpm), so your only going to get 15 to 20 mph. I put a SD diesel in my 521 kingcab, with the shortshaft 5 spd. the shifter comes out the stock shifter hole. Link to comment
wayno Posted July 12, 2011 Report Share Posted July 12, 2011 The SD bell pattern is the same as the U20? Yes it is ggzilla, but can you bolt a 720 shortshaft to the U20 bellhousing/front case? Link to comment
wayno Posted July 12, 2011 Report Share Posted July 12, 2011 Of course you might be trying to put a shortshaft tranny behind a U20 block for racing or some other application, as U20 trannys are expensive. Link to comment
wayno Posted July 12, 2011 Report Share Posted July 12, 2011 Will the SD25 5 main crank fit in the U20 block? Link to comment
ggzilla Posted July 12, 2011 Report Share Posted July 12, 2011 can you bolt a 720 shortshaft to the U20 bellhousing/front case? Why bother to swap bell housings if the SD and the U20 use the same pattern? Whether or not the 720 short tailshaft transmission is the desired length is another question. Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 Of course you might be trying to put a shortshaft tranny behind a U20 block for racing or some other application, as U20 trannys are expensive. im trying to put one behind my r16 since the u20 trans is too long and expensive. Will the SD25 5 main crank fit in the U20 block? u got me there.... no clue. if anyone has a sd crank i have a r16 just sitting with no crank in it. Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 Yes it is ggzilla, but can you bolt a 720 shortshaft to the U20 bellhousing/front case? no the u20 trans was on its own and even tho its a fs5 its a different style center gear carrier and the pattern is different Link to comment
ggzilla Posted July 12, 2011 Report Share Posted July 12, 2011 The Datsun 2000 Roadster came with FS5C71A didn't it? Front cases don't switch between 71A and 71B. A has a bolt-on bellhousing. B has front case with integral bellhousing. Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 The Datsun 2000 Roadster came with FS5C71A didn't it? Front cases don't switch between 71A and 71B. A has a bolt-on bellhousing. B has front case with integral bellhousing. its the difference between a fs5W and a fs5C that makes it not interchange. from wat i read iirc the dolt on and integral fs5C's can swap internals between the 71a and 71b but not the 71c. i cood be wrong and most likely am Link to comment
erichwaslike Posted July 12, 2011 Author Report Share Posted July 12, 2011 http://www.gracieland.org/cars/techtalk/gearing2.html some good info on trannys Link to comment
Master-O-Turbonics Posted July 13, 2011 Report Share Posted July 13, 2011 Why bother to swap bell housings if the SD and the U20 use the same pattern? Whether or not the 720 short tailshaft transmission is the desired length is another question. Half of the Datsuns in the world have a FS5W71B transmission that the SD22 uses... and there are tons of different ratio gearsets out there for 71B gearboxes. (and with 4+ different swappable 5th gear ratios: .75(maxima), .77(some zx) .813(720), .86(close ratio 280Z) that I know of). I have yet to run across ANY roadsters in junkyards or that are available for stripping parts off of... I may be willing to ship you the bellhousing alone, as I can take the 5th gear off the diesel trans and use it in building a spare race transmission out of a maxima trans. price isn't going to be any different though since the bellhousing is about the only valuable part to me. LOL Link to comment
datzenmike Posted July 13, 2011 Report Share Posted July 13, 2011 The overdrives tend to be in the 12%-19% range with he '81-'83 non turbo zx having a 23% and a 26% drive. The gears inside can be the same and varied by simply changing the input and counter drive gears. Link to comment
merlin Posted August 12, 2011 Report Share Posted August 12, 2011 I just pickedup an sd22 rolling frame ... Very interestiing as i have an r16 roadster too hmmm is there a write up on this conversion anywhere? Link to comment
datzenmike Posted August 12, 2011 Report Share Posted August 12, 2011 FS5W71C from 240sx with diesel fromt case swap. Merlin here's my diesel front case I took to Canby in 2010. Here is a Roadster bell with the bolt pattern cut off (don't ask) Almost all the holes are the same as the diesel, maybe slightly smaller. We test fit the roadster over top of the diesel and it matched. . Link to comment
erichwaslike Posted August 12, 2011 Author Report Share Posted August 12, 2011 I just pickedup an sd22 rolling frame ... Very interestiing as i have an r16 roadster too hmmm is there a write up on this conversion anywhere? i havent seen one posted, i just did the research and it will work tho. no real step by step instructions till i get mine and document it. mike, u really gotta stop wearing those mandals(crocs) u got on man. :P Link to comment
datzenmike Posted August 12, 2011 Report Share Posted August 12, 2011 Hahahaha I 'built them' two years ago this month. Link to comment
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