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Discussion Starter · #1 ·
I recently purchased a '73 blazer that was in pretty rough condition. I took the body off yesterday and after everything else is apart I'll take the frame to be sanblasted and painted. Now I'm just trying to decide on drivetrain. I most likely will get the 350 GM crate engine so I'll be getting around 350 HP. I have a NP203 transfer case that I will use. I just need to decide on a Tranny. Standard or Auto? I've heard the SM465 is a good choice for standards but will the bolt up to a new 350 and the 203? I haven't heard many things about Automatics. Like which ones are better than others. Any advise would help me a lot. Feel free to tell me if I've overlooked anything. Thanx

Chad

 

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Can't really tell you what too usewithout more info.(i.e what kind of stuff will you be doing with it etc.) But 203's Most often came behind autos so it whould be easier too find an adapter at a j-yard if you had too.

A Man a Dog and a Pickup it's a wondurful thing(sometimes)/wwwthreads_images/icons/wink.gif
 
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Discussion Starter · #3 ·
I want it to be an all around 4x4 with crawling capabilities. It possibly could be a trailor queen.

Chad

 

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Well if you want too really crawl the SM-465 whould be really good for that with it'd 6.55:1 granny gear.(And it's strong too!) Most autos don't have a real good 1st gear ratio for crawling, The 700-R4 has a good 3.06:1 1st but can be weak if you don't put build it right. TH400's which most people think are the strongest auto ever built for a light truck, Have a 2.4something:1 first and it's little brother has a 2.7something:1 1st.
A little more(useful I hope/wwwthreads_images/icons/smile.gif) info for you.

A Man a Dog and a Pickup it's a wondurful thing(sometimes)/wwwthreads_images/icons/wink.gif
 
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Discussion Starter · #5 ·
if it were me id go with a JET 700r4. they build em up good and strong and like someone said, they have a good first gear. ive never heard anything but good things out of the JET built ones

Mike ~
* Earnhardt Forever *

89 Chevy K1500 - 350TBI/700R4/NP241 - 3" lift - 33's
 

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Personally, I would go with the SM456 and also get the NP205. You can get a used 456/205 combo for really cheap. Cheap as in lets say $500 is on the high side for them together!!! thats cheap/wwwthreads_images/icons/wink.gif

One thing I like about the combo is the amount of HP you can put through them. I am putting them in my Truck Puller for two reasons. 7 guys that pull up here that I know have them in there truck and are putting at the least 500HP through them and one guy is running it in his modified 4x4 and he is running 1200HP from an Alky 620CI engine and has had the same trany/T-case in the truck for 3 years with out a single problem. The other reason they are great is that with the gearing set up the way it is you can run in Low in the trany and High in the T-case or 1st in the trany and Low in the T-case and the final ratio is almost the same but at the same time when you racing in mud or pulling a 20,000LBS sled like I am that little extra RPMs in the rear means alot.

Anyway, thats what I would do....Ryan

93 GMC Yukon
Chevy SuperStock 4x4 Truck Puller
Great Lakes Truck & Tractor Pulling Association
http://www.greatlakespull.com
 
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Discussion Starter · #7 ·
If I were to put in a Standard how much more complicated would hooking it up be than an automatic? It has an automatic on it right now. I've been told the linkages are a *itch to get to work right. Seems to me all there is a shifter. I guess I'm wrong.

Chad

 
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Discussion Starter · #8 ·
Hello, I just completed a conversion from the TH350 to the SM465 in my 1978 GMC Jimmy. Pretty much everything bolted right up. I bought the plate that holds the linkange to the frame at the dealer, and used junk yard linkage. I would recommed buying a new clutch fork from P.A.W. It cost 30.00 I think. I also had to slightly modify the brace behind the guages in the dash that the pedals mount to. I am going to replace it as soon as I can find one in a junk Yard. If you are interested I can answer more specific questions. By the way I love the SM465. It doesn't shift fast like a Muncie car tranny but the Grannygear is way cool.. Lazydog

 
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