Big Block help needed

[c502]

Hi all. I've read about every post I can find on doing a BBC swap in my 71 K5. I have this pretty Ram Jet 502 in my garage, a custom rebuilt Turbo 400, and a fresh NP 205 ready to drop in, except it won't just drop! 2" body lift and I'd really prefer to not hammer on the firewall because I'd have to hammer a lot. Also, the stock crossmenber and the oil pan are hitting in multiple places using the small block mounts..

I have tried the following:
1) Placing it on the stock small block mounts. See above.
2) Buying Big block 2wd towers. Obviously that wont work.
3) Pulling a motor out of one of my many 73-87's to get the crossmember out of it. I would have no problem drilling the frame and moving it forward but the actual mount (the parts that bolts to the engine and the crossmember on each side) is at least 1/2" too large to fit between the 71 frame rails.

I don't mind spending the money to find something that works but I need some advice which way to go. Any advice would be appreciated.

[jaros44sr]

Number 3, Burt 4x4 in cali area did exactly that, he said he saw it in an old article and it worked for him. Don't know about the 1/2", but this is just what I've read. Didn't do it, yet. J

Oh, I almost forgot, welcome to the boards from Philly. There will be others along to give you their .02

[vtblazer]

Check out CK5, several great threads over there about big block installs.

What are you planning on using this monster for?

Two words come to mind...frame twist.

[jojotonka]

Well, You probably seen some of my pics if you did research. I used a Milodon oil pan with the stock cross-member and had no clearance issues, however, I had major firewall problems. I did it the ghetto way and beat the stuff outta the firewall. Part of that problem was the tall valve covers.

I was nervous about moving the motor forward, therefore moving tranny and transfer case forward as well. In turn, making you rear driveshaft to short and your front driveshaft to long. ????? Everyone here has different opinions.
IMO it depends on how custom/show is your vehicle going to be?
Is it going to be a trailer queen for car shows?
Or is it going to be a badass BBC that gets noticed for what it can do... not how it looks.

But on the flipside.. If you have that much cash wrapped up into the driveline, buying driveshafts and moving everything around probably isn't an issue.

[c502]

Guys, I'm going to wheel the ever living *&$# out of it. Trailer queen isn't even in my vocabulary. I'm a big block junkie. Making driveshafts isn't an issue, I was going to do that anyhow so changing locations of mounts is fine.
I've looked over at CK5 and see the same info but I'll look at it again. I really like the idea of the 73-87 crossmember because I won't have oil pan issues and I can move then engine forward to clear the firewall.
I just wish I knew how those guys made the 73-87 stands fit the frame rail!
Thanks for the help!

[jojotonka]

My two cents again!!!

If your gonna rag the snot outta your rig, why worry about the firewall??

IMO It's alot easier to change an oil pan versus swapping cross-members, and moving driveline forward. Not to mention your making your front driveshaft angle that much more angled, when you move everything forward. I can't imagine the angle your going to have already from 12" of lift.

[c502]

It's a valuable two cents too and is appreciated. Only have 6 " of lift by the way. I'm messing with all options now so no working solution is being thrown out. I guess the reason I'm shying away from the bashing in the firewall is just from wanting to do the driveline right the first time and I'm being picky I suppose. While the exterior body might never get done, when buddies open the hood I want them to see clean work, not a bashed in firewall. However, your points are well taken and I might go that way anyhow. If I go that way surely I'll get over it!

[jojotonka]

Woops!!! I got two different threads confused... 12" of lift was another member.

Anyway, I found some pics that show you the ghetto hammer!!!
And I'm already over it!!!!!!!
BBC's are awesome!!!!

[vtblazer]

Originally Posted by c502

I want them to see clean work, not a bashed in firewall. However, your points are well taken and I might go that way anyhow. If I go that way surely I'll get over it!

One variation to the BFH method if you want a 'clean' look could be done two ways.

1) shape a piece of wood to a sutable shape (roundish) and bash on it...you wouldn't get the hammered look but you'd still get the clearence.

2) cut out the part of the firewall that hits and weld it back together using a metal piece that allows for the clearence you need.

Yukon Jack did the version #2 on his BB install.

[Yukon Jack]

A guy over at CK5 did something I hadn't thought of - he dropped the engine 1" by using spacers between the frame and the crossmember - he reported that that really helped him get his bbc installed. I have too much body lift and had to cut my firewall to make my bbc fit. In the future I am going to drop the engine or move the engine forward so I can get rid of part of my body lift. If you cut the firewall you need to be aware of whether that will interfere with your heater components inside the vehicle and your gas pedal. My 69 has the hard linkage style and had to be careful to not screw that up.

I used the stock crossmember and my bbc is from an 89 1 ton. My oil pan was very close to the crossmember so I used a few washers between the motor mount and the block to raise the motor up. That of course doesn't help me with my firewall clearance.

If I had it to do over again, I would definitely drop the motor down and have a custom crossmember built. That would help my swap alot.

Be aware that for whatever reason, some people have major fitment issues while a few people have posted that they had absolutely no problems sliding a bbc into place. Still makes me scratch my head!

If you go to my website in my signature you can see lots of pics and info on my bbc swap.

[c502]

Once again, many thanks for the help. I also scratch my head with some having it easy. The first time I read that I knew I wouldn't be in that group, I never have been so lucky!

Part of the reasons I dont want to do the firewall bash is that with clearance so close, and the obvious frame/body flex that will happen while wheelin', the noise of the motor hitting body can't be good. I had an early Bronco once in my life with a big block Ford motor (sorry for my youthful stupidity!) that had the same situation, motor hitting the body, and it wasn't ever pretty. made my head hurt listening to it.

No problem moving the whole thing forward and inch or two if I need to, just need to make the crossmember work. That DIY4X set up may be the way I go. I'm still wondering if there aren't two sizes of motor stands on the 73-87 crossmembers because the one I have doesn't fit! I guess I can put the 84 one ton back together now since I robbed it for parts to get the crossmember. I've swapped big and small blocks at will with the 73-87's and never even noticed a difference.

YJ, I'll check out your web pages. Thanks.

[dentmaster]

I was curious...I am doing the same exact install. If you change the oil pan, and slide everything forward..( of course adjusting the length of the dtriveshafts). How far would you need to move it all forward? and would you have any other issues? thanks for all of the help.

[c502]

I decided to go with the diy4x crossmember, ordered it up today. Thanks to all for the help, I'll let you know how it goes!

[70rs/ss]

I have a stock 454 out of a 73 and up truck. it is mounted in the rear holes and lines up fine. the hei is close to the firewall, but not so close it won't work. the motor in the forward holes if where the BBC should be from the factory (2wd that is no BBC made it into 4X's) but using the factories logic, the BBC in the forward holes will make it all fall together. you can get away with the rear holes if you use the small capped distributor. the only thing I saw you were struggling with was the oil pan, and that is probably because you have a car pan of the 502 (deeper in the front to offer more ground clearance). Find a good truck oil pan and the factory 4X crossmember will work A OK? Sounds like all my advice is a day late, hope the new crossmember makes everything all right?

[c502]

Not too late but it is a truck pan on both the 502 Ram Jet and the 502 motor I'm using for test fits. Using the stock small block towers and crossmember I was hitting on valve covers and cylinder head, although some of it was the head studs on my test fit motor. I'm just one of those guys who always has the challenge scenario no matter what I build!