Anyone tried AA's adaptor to mount a NP203 as a gear reduction in front of a LC 3 speed TC? I'm thinking of using this to put a mopar V8 in instead of a SBC.
NP203 gear reduction box--Anyone tried it?
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- #3
While cruising the junkyard, I spotted a York standalone compressor. It was attached to a 318 so I thought why not try this instead of a sbc. Silly impulsive me bought the whole motor with rebuilt 727 and NP203 for $300. Then I discover that nobody make adapters. I had a Scout II for a few years and got spoiled by the auto trans. I thought that if I adapt it to the toyota and flip the rear springs I could get the double gearbox and be able to keep the stock 3.70 gears for highway and have a good crawl off road. My other alternative is to use the 318/727/203 with minitruck axles, which I have with 4.10 gears, to have a centered rear cheaper than a custom housing. I plan to run 235/85-16 tires which work out to 32 x 9.50 for light trail work. Watcha think?
Like HI^C said the main thing you have to deal with using a doubler is driveline length. If you can make it fit go for it. I wouldn't use the NP203 solo though its really long and has terrible low range gears.
You could also look into a NP205 behind the NP203 and use pickup axles, check into differences in doubler adapter and transfercase lengths. Besides if you can get the NP203 to fit whole, you can get a 203/205 doubler to fit, they are close to the same length. You might be able to make up some length there as well.
You could also look into a NP205 behind the NP203 and use pickup axles, check into differences in doubler adapter and transfercase lengths. Besides if you can get the NP203 to fit whole, you can get a 203/205 doubler to fit, they are close to the same length. You might be able to make up some length there as well.
If you are dead set on the 318 you might get it to fit by doing a spring flip in the rear which moves the rear axle back 3.5". You might also consider moving the motor as close as possible to the radiator. IIRC that 727 is really long.
The only reason anybody else uses a 203 is that they want a strong, inexpensive doubler.
The only reason anybody else uses a 203 is that they want a strong, inexpensive doubler.
203/205 combo puts the rear output in exactly the same place as the 203 alone. Same overall drivetrain length.
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- #7
Thanks; lot to think about. I may just sell the mopar and save my lunch money for a sbc.
If you got it laying there, pull some measurements off the trans, trans adapter to t case, and then overall engine length. Try to help layout your crap. I do not do mopar stuff really, so i have no hard numbers.
All for trying different engines, I got OLDS engine laying about all early 70's high compression, 2-455s and a 350. One 455 might end up in the other 40. NO F*** crap though, lol.
Driveline length is the biggest problem with autos, then trying to doubler it also.
All for trying different engines, I got OLDS engine laying about all early 70's high compression, 2-455s and a 350. One 455 might end up in the other 40. NO F*** crap though, lol.
Driveline length is the biggest problem with autos, then trying to doubler it also.
I am running a 350/TH400/203/toy case The motor is as close to the taurus fan as possible, the springs are flipped and SO. it is close. The tube on the rear driveshaft is only about 3 inches long. I will try it like that as a 100% trail rig until I do the four link and move the axle back another 4-6". The doubler adds the same if not a little less than many adapters. The NP203 to toy case is a 1" plate and the GRB for the 203 is only about 8". It is a great way to adapt an auto to a Toyota case. I would do it again in a second, especially in a longer wb rig. (working on a 55 deal as we speak 
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- #10
Gumby,
Any pics of the driveline from a snails' eye view would be most welcome!
Any pics of the driveline from a snails' eye view would be most welcome!
Got it!! Love it!! Do it, you will love!!!
run'n gear...
http://www.lslc.org/austin/bios/blumenthal/rungear.jpg
Oher pics...
http://www.lslc.org/austin/bios/blumenthal/Dulciena.html
run'n gear...
http://www.lslc.org/austin/bios/blumenthal/rungear.jpg
Oher pics...
http://www.lslc.org/austin/bios/blumenthal/Dulciena.html
Gumby said:I am running a 350/TH400/203/toy case The motor is as close to the taurus fan as possible, the springs are flipped and SO. it is close. /snip/ It is a great way to adapt an auto to a Toyota case. I would do it again in a second, especially in a longer wb rig. (working on a 55 deal as we speak
That is my exact setup in my 60. Have the stock radiator and shroud in with the SBC lined up perfectly to it. My drivelines are almost equal in length, a great setup for a longer rig.
You would still be much better off with a toy box doubler than the 203 if you insist on an automatic tranny. I'm pretty sure you could get a longer drive shaft without hacking your truck up.
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- #14
Okay. Since it will be some time before I can get back to this thanks to taxes 
, which would be better or cheaper; 203 plus LC 3spd or 203 plus 205?
, which would be better or cheaper; 203 plus LC 3spd or 203 plus 205?better 203 to 205
cheaper 203 to 3spd,
you have the 3spd, adapters are a bit cheaper for the 203to205, the centered rear output of the 205 makes this a bit more costly. You could combine a 205 and np200 for offset rear output. 205 can be costly to buy or costly to make one work.
DEPENDS on what you can get your hands on and for how much $$$$$.
cheaper 203 to 3spd,
you have the 3spd, adapters are a bit cheaper for the 203to205, the centered rear output of the 205 makes this a bit more costly. You could combine a 205 and np200 for offset rear output. 205 can be costly to buy or costly to make one work.
DEPENDS on what you can get your hands on and for how much $$$$$.
There's something to be said for 203 to split case as well.
I wouldn't do the Toybox behind an auto cause you can't stop the truck..
If you have a split case then that's the way to go for strength.. Or grab a 4spd case cause they're quieter.. Does it matter if you lose a touch of gearing for strength.. Your wanting auto right? That basically doubles your crawl.. I have a 700r4 to Toybox with 4.7's and split case and I can't hold the truck back in gear! Not good but really cool!
203 is cheap and effective, if I were to do it again behind an auto it'd be a 203.. Behind a stick.. ? Go gears!
If you have a split case then that's the way to go for strength.. Or grab a 4spd case cause they're quieter.. Does it matter if you lose a touch of gearing for strength.. Your wanting auto right? That basically doubles your crawl.. I have a 700r4 to Toybox with 4.7's and split case and I can't hold the truck back in gear! Not good but really cool!
203 is cheap and effective, if I were to do it again behind an auto it'd be a 203.. Behind a stick.. ? Go gears!
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- #18
I guess my other alternative is to try and match the mopar to a toy 3 speed and forget the gear doubler. That driveline is way long even with the 203 by itself.
If you're determined to use the mopar try contacting Pete Moesser in Evanston Wyoming. If he can't help maybe his pal Flyin Bryan Shafer might be interested. They both used to run Chrysler powered Cruisers At hillclimbs and sand-drags back in the 70-80's. They are both machinists.
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- #20
Anyone got an email for Flyin Bryan or Pete ?
