I am thinking about building a new mudracer for our tracks around here. My 70 is just too big for the races around here and the 4-speed is not really the best tranny to have for doing this. So I am going to keep that as mainly my trail rig/play toy. Also a friend of mine who wasnt even racing when I used too is talking a little trash because he is kind of cleaning house at the races in ALL divisions...and the worst part of it all is he is driving a heep pickup. So I am thinking of putting a 460/C6 combo in my 78 shortbox, gutting it and shutting him up. I wouldnt race until next year and probably not get started working on it until later this year if I decide to. I have an extra set of L&L motor mounts laying around, is this all I will need to put the 460 in it?(originally came with 400) Will I need a new crossmember for the C6? I will probably be running boggers around 35''. I want to make the 44/9'' live. What do you guys think about this build? Any suggestions welcome.

 

the trans crossmember will work fine, you can start with the L&L mounts but odds are you will be replacing them, and if this is dedicated trail rig get some solid motor mounts. I would have to check again but I think it is greenhighboy that makes them, maybe he will chime in if he is still doing that, I have had them on my motor since last year and nicely done. (I feel so bad right now can't remember for sure who it is dang and I even met him at the block summit down in MO last year, dang that is bad expecially since he did such a nice job for me and is reasonable on price, so sorry if you read this, just hit me in the head a few times). Also you will need accesory mounts for alt, PS and of coarse headers.
Making the 9" live is easy so won't even get into that too much, but good gears are worth the money, and used nascar gears polished can be got pretty reasonable and I have been running them for 4 yrs, those guys buy the best gears money can buy and run them one race so they are great at half the cost of new. The D44 in mine lives just fine, but maybe I am just lucky since everyone was betting on how long it would last and all I have done is replace a couple axle joints and I use NAPA branded cheapies, with stock axles, a spool, and a factory ring and pinion.But then again I don't intentionally jump my truck either, not that it hasn't seen the air more than once. One suggestion is set it up pretty tight if all your gonna do is mud race with it. Another suggetion is don't run locking hubs go with drive flanges from a full time 4x4, doesn't matter what they come out of as long as it's a D44, mine are actually out of a 76 chev (wifes son had full time and my axle had locking factory hubs so I just traded him), those are stronger and less parts to break plus if you break an axle at the track they are a lot faster to get out without loosing parts to change it or do anything else to it.

 

I was planning on the drive flange idea...I know I have a set down at the shop but I'm not sure what I pulled them out of, they could have been out of a 10 bolt. The shortbox has what looks to be rear springs out of a highboy and the front sit's higher than most stock fords of this vintage. I will try to post some pics soon. By the way it has a np-435 mated to an np-205. The c6 i have is mated to a 203. What is the weight difference between the 205 and 203? What would the 203 be worth...or possibly just the range box if somebody wants to make a doubler.

 

I have no idea what a 203 would be worth, you will need the adaptor for a C6/205 to do that although I can't remember if they can be modified to work or not. I do have both a long and short adaptors here as well as a couple spare np205s.

 

Your better off getting rid of the 203.
It is chain driven, and the shift linkage doesn't work worth a darn.
It also weights 300 lbs.

I'm trying to swap mine too, but don't know which adaptor I need....

monsterbaby, with a C6/203 that has a short adapter, I need the short 205 adaptor?
What year truck would the short adaptor have to come out of? I have a long one, but of coarse it doesn't work.
Not trying to steel the thread or anything....

Hope you get to show your buddy up!

 

Ok so I would need a different adapter to mate the c6 and 205? If so I may just use the c6/203 combo since this is going to be a race only rig and the fulltime case wont bother me. I dont think I will be putting enough power out to break the 203. Also what would you recommend on tranny (c6) upgrades for around 400-450 horse 460? I have no idea of the condition of my C6...it will probably need a rebuild. The fluid is a little dark but does not smell burnt.

 

The C6 can handle ALOT of power( I want to say 900 HP). All you would need to do is a possible rebuild like you said with a shift kit.
IF the 203 isn't already converted to part time, it might be ok to use like it is. It's stronger than most people give it credit for, but I'm sick of messing with mine.

You might have to replace the chain inside(expecially if you don't know the condition of it). They usually last about 200,000 miles, but with a good bit of power and hard abuse I've heard they only last 50K-100K miles, which is still plenty.

Just curious, would be be doing the gear work yourself?

 

Sorry but the question is a little vague...I will be doing all of the work myself except for the auto tranny work. If the 203 comes apart I wont be out much money. The rig it came out of had about 120k on it. I spun the yokes back and forth and it feels OK...not too much play so I will probably just run it. I want to keep the cost of this down as much as possible, most of the money will be in motor,trans, tires with the majority of it going into the tranny...most of my money goes into the 70 f-250. I will either take the 460 out of my 70 for the engine and start building my stroker OR if I can find a good junkyard (haha good luck huh) engine and work it over and then I will put that in it.

 

Sorry, I was talking about axle gears(ring and pinion).

If you weren't I was just going to suggest MAE racing for the rear 9" third member.
I want to say they use the used Nascar gears monsterbaby was talking about with timken bearings and seals. I got a complete third member with 4.56 gears, 31 spline, full spool, and everything already installed for $500 shipped to my house.

Now this is one thing I don't feel comfortable doing on my truck, b/c I've never done it before and didn't want to mess up, and my off road shop would of been charging about $700 with tax.... Just to say.

 

what carrier did they give you with the, hpe it was a nodular. used nascar gears around $100, billet steel full spool around $110, timkin bearing kit would have to look but if I recall correctly the last one I bought with the bearing for the daytona pinion support and big bearings was $120, setup shouldn't be more than about $50 (atleast thats what I end up charging most of the guys around here, the 9" is simple) stock carriers are pretty good, but I went with the strange nodular and alum daytona pinion support, billet spool, billet 1350 yoke.
As to the C6 building a 500hp capable unit is pretty simple actually (and no they won't handle 900hp for very long without some serious more expensive mods, just ask me sometime) go with alto red clutches, kolene steels, if it's race only go with a manual valve body, upgrade your clutch packs to 5 per pack (some this just involves taking out the wave plate which I do anyway), and use a kevlar band for the intermediate band. Also either use an Rcode servo or F code lever, do not use those together, max I would suggest is the E code lever with the R code servo (this is what I am running, and upto about 600hp you can get away with the R code servo and even a B code lever)

 

I notice you have asked this twice with no response figure I better answer you. the one that is in my truck came from a 77 F150, the other one I have come from a 79 bronco I am thinking but not totally sure that your going to find them in the short wheelbase trucks but the 77 was a standard cab F150 so maybe it's just the later 70s I don't know for sure that there is any one answer to the question but I do know every 78 and 79 bronco that I found with a 205 had the short adaptor.

 

Monster...do you have a rough estimate how much a built c6 like you described would cost in total???

 

parts alone (you doing the rebuild) you should be able to get for around 450-500 including a manual VB, a built tranny not sure probably in the $9-1000 range would be my guess maybe a little more or less but in that range.

 

How much will a c6 recently rebuilt ( close to factory specs) with a B&M shiftkit handle in HP? I may be able to get it cheap.

 

It will most likely handle your 450hp pretty good for awhile. I would put an alum pan on it, good cooler, and run synthetic fluid in it as well as running an external filter either in the cooler lines or as a bypass unit (ford actually makes one that works pretty good, same as the filter ford sells for the PS system and you can get it from NAPA also) that should make it last pretty good for quite awhile. The B&M shift kit is ok I guess but I would still either convert it or buy a manual VB if your going to just use it as a race rig that gives you more control over your gears.