[Bbc 454 k5 2wd]

I want to convert my 79 k5 4x4 to 2wd 4 speed looking for 550 to 600 hp (eventually) sitting at around 368 or so (with good tuning of my carb ) so I'm pretty sure a 700 r4 will get it done but is there a better choice? especially when I start adding power????

Motors a early eighties late seventies 454
Any advice is better than where I'm at

[cobalt327]

I had a '76 2WD Blazer, kept it for years as a DD/parts chaser. I'm wondering why you'd want to go to all the trouble to convert a 4WD to 2WD when the 4WD are generally worth more (if working). What I'm getting at, is couldn't you sell or trade the truck and buy a PU or even a 2WD Blazer (although they're uncommon) easier than converting?

But in any event, what trans you need will depend on if the truck will be used for towing and/or used as a TRUCK, or if it'll have an easier life of a cruiser, or not used as a truck.

If it'll see a lot of heavy duty use, there's the 4L80. If not a 4L60/700R4 will do. At some point (like how you will use it and how much power the engine is making), one will make more sense than the other. The mods to make them stronger are fairly well known and being as how I'm not a trans expert by any stretch, I'll leave those details to someone w/hands-on experience.

Don't neglect the rear end, either. It's a "12-bolt", but not as beefy as the car 12-bolt. At some point it will need attention too.

[adantessr]

I'm definitely onboard with Cobalt on this one. Are you really planning on getting rid of the transfer case and front axle and installing the IFS ? That is a LOT of work. Selling what you've got and buying a 2wd would be much more cost effective and much less work. Pull your 454 and replace it with junkyard 350 to sell the vehicle. Easy engine change on that vintage.

[Bbc 454 k5 2wd]

The issues I'm having are the turbo 35O trans is NOT doing justice AT ALL and my transfer case don't function rite I'm almost curious as to if I just have linkages hooked up wrong or if I'm just not as smart as a 33 year old 4x4
Don't get me wrong 4x4 is why I own the damn thing in the first place as I traded a 250 mph bike for this truck I've grown up in a faithfully blue oval world and avoided the bowtie at all cost but this blazer has made me a believer
Anyhow if I was to stay 4x4 which from what both of yous says is the more logistical idea what should I do about getting a four speed behind that big block? And is there an ideal 4x4 setup that would be nice for this truck? It's DEFINATLY not gonna pull anything heavier than a bike trailer as its DEFINATLY just a street queen by ALL means I just hate it running out at fifty I know that has to do with diff gearing as well so for safe measure I'll tell you guys now there 4.11 front and back ( according to the guy I bought it from )

[adantessr]

I'll confess right off that I'm not entirely sure what trans will bolt up to your transfer case. I think that it is the 200R4, but may be the 700R4. I'm sure somebody here knows. As for the transfer case problems. If you have the fulltime 4WD transfer case that came without lockout front hubs, they are notorious for the chain and sprockets wearing out over time, and it doesn't matter if the transfercase is in a Ford, Mopar, or GM, the symptoms are the same, it bangs and jumps. If that is the problem that you are experiencing, the sprockets and chain are replaceable. If it were me, I would put the part time 4WD kit in the transfercase at the same time which eliminates the differential gears in the transfercase, and install a set of lockout hubs while you are at it. I hope this helps. On second thought, maybe pick up a 4 speed AOD trans and tranfercase from a salvage yard and be done with it.

[Bbc 454 k5 2wd]

No it has the manual locking hubs already I have climbed under it and checked the drive shaft prior to locking the hubs and it turned the universals on both sides but after locking the hubs there's nothing and I'd I try to drive it in 4 wheel it hums something serious idk what this issue is from I have been told that different size gear drives in front than back or visa versa could cause this any ideas?

[speedbump]

Get a well built th-350 and it will take care of your problems. With today's parts, they will handle 600 hp easily. You'll be disappointed with a 4 speed and the big block. I've gone the other direction twice. The auto, whichever you choose, is a better 4x4 trans than the old style, granny gear, four speed. Also, those t-cases are easy to rebuild. Have somebody go through it and make sure it's a true part time case and not a converted one. There were a number of cheap conversions, including hubs, but, IMO, only one good one made by DNE. That could be your problem.