Time to get serious... LS motor in my 48

[Smokeybear]

I've spent a couple of years now cruising the L6 and although it's been good, she is starting to show signs of age. She's picked up a smoking habit and goes through a quart of oil every couple of weeks. She's also down on power and it's a crying shame a car that looks this good has to be this slow.  An opportunity has arisen to buy a buddy's car. He smashed up his 02 Firebird with the LS/T56 combo a few weeks ago and I can get it for a song. It's a stout car with only 68K on the clock. I've only seen one other LS motor in a P15 and it was in the HOT ROD mag. BUT it had all Corvette underpinnings. I'd like to keep my car with the original frame (if possible). I received the disk brake conversion for Christmas and swapping the rear for an Explorer or Jeep rear end with disks is no problem. It already had an Explorer drum rear now. My concern is if the LS will fit. I can fab custom headers if needed but the stock F-body manifolds look like they'll hug the block enough to fit. I don't mind doing some firewall and trans tunnel surgery, it's the steering that has me a bit concerned. I know I can get a fatman's kit to convert to rack and pinion and that should free me up some room behind the cross-member. I've looked at it 3 ways til Sunday and I have these options, which in your esteemed opinion would be my best bet.

 

1. Original frame and front suspension. Add disk brake kit and fatman's R&P kit. Hope the LS fits and work out the oil pan and manifold clearances. I'll definitely have to fab the motor and trans mounts (not a problem), and use an aftermarket aluminum radiator. Pros -Not fiddling with a frame stub or swap, with rear swap and front disk kit, brakes would be OK, depending on luck of the fit, the least amount of work and quickest back to roadworthiness. Cons -May run into fitment issues with the cross-member and/or steering, More likely to have to do firewall surgery.

 

2. Stub frame with Dakota front clip. Pros -Disks and R&P done in one swoop, Less likely the fitment issues from cross-member and steering will arise. (There have been several LS swaps in Dakotas with no problems.) The track width will fit nicely with the wheels I have. (front stockers). Cons- More work to install the clip, possibility of weakening the frame, having to deal with fitting the front sheet-metal on the Dakota frame. 

 

3. Go with an S-10 or 98 or newer Ranger full frame. Pros of the S-10- Wheelbase of the reg cab long bed is identical to the Plymouth. The track-width is narrow enough to be able to use adapters to fix the lug pattern problem. Off the shelf parts to drop the engine/trans combo into the S-10 frame. Pros of the Ranger- Wheelbase and track-width are perfect on a regular cab long bed. Wheel bolt pattern is already correct. For either of the frames it's easy enough to get lowering parts or go with a bagged setup. Cons- A lot of work to marry either frame to the Plymouth body. 

 

 

 

So, if I go with the full frame swap, It's more work but I can stop at any part store to get parts for anything that would cause a major breakdown. I've done some major swaps and some major restorations before so the skill level is there. I'm just looking for the most economically feasible and logical path. So what say ye gentlemen?

[Don Coatney]

Your car, your choice. Go for it. I can only tell you what I have done to my car. I cannot tell you what you should do with your car.

[Robert Horne]

The "most economically feasible and logical path" would to buy a good running similar stock engine,

install, and start driving soon.

I bought my flathead engine, $150, from a guy going all modern with his project.

I bought a spare engine, 1956, for $50, runs good...

And there would be nothing wrong with anyone installing a 350 or any other type engine.

[Old Ray]

I am also doing my R & D in regards to some kind of front suspension change and I think that you are looking for input / suggestions that will help you make your decision.

 

 I have found that you can get too much information and go into data overload and it usually just makes things more complicated.  It is human nature for a recommender to say what they did (or would have done) is best, so it’s a bit self-serving.

 

So here is my biased self-serving opinion considering I’m just in the research stage (on this project) and haven’t actually done anything yet (aka wanker).

 

Option one: Most likely fitment problems and old technology (sorry die-hards).

Option two: The Dakota SUB-frame transplant looks like the way to go.

Option three: Frame transplants of any kind are difficult and mega work.

 

Keep in mind that opinions are like bums, everybody has one.  

 

PS.

Oh, speaking of vested interests, I would like you to do a build thread so that I can see how to do MY recommendation.

Edited January 13, 2014 by Old Ray

[mrwrstory]

                        Here's what I did #1 and what I might do instead,...... #2 if did it again.

#1 - I patched in a complete Kugel Komponents IFS front crossmember and retained all the front clip mounting points.  Got me disk brakes, coil-overs, R&P and pan clearance.  Min. firewall mods and bolt-in radiator (on the front of the core support).  There are similar crossmember kits from Morrison, Heidts and others.  If you call them, their response will be, "we don't have that".  However if you study the information and persist, you will see how it can be done.  I am extremely happy with my result on all counts.  I have no second thoughts.  I probably have about 5k miles on the build with no problems.

#2 - If I had it to do over, and knowing what I know now. I would seriously consider doing the purpose built Fatman clip.  It essentially gets all the features in the above description in one package.  I believe it would be less work.  However, the fabricated Fatman clip assembly has the "fabricated" look and I like the stock frame appearance better.  

I'm looking at the same project for a 40 Plymouth and it's a tough decision.

Shoot me questions if you want to know more.

[james curl]

I have seen all of the photos of Bill Story's build on his car, it is all here on the site for all to look at.  I would recommend that any one thinking about a front clip of any type check out his build thread.  He did his homework and it looks to be simpler than a clip from another vehicle.  If you cannot find it I am sure Bill would be glad to direct to the location so you could review what he did, and he would probably answer any questions you might have.  Of all of the builds that I have seen here including the very good ones from Tim Adams this one impressed me the most, to me it would be easier to duplicate than the Dakota swap that Tim does as it can be done with the body on the car.  Note I said easier not cheaper as the Dakota frames are cheaper than the fabricated front suspension units.

Edited January 13, 2014 by james curl

[deathbound]

I think this is Bill's thread that James is referring to......probably one of the most informative builds on this site. http://p15-d24.com/topic/22985-im-back/?hl=%20i

[mrwrstory]

Wow!  Thanks Derek and James.  Thanks for that.

I clicked on the link and spent an hour reminiscing.  A lot of good friends both in person and online made it special.  I noted that many pics were gone and I understand that's 'cause I changed some on Photobucket.  If anyone wants to view something  that has been deleted, just give a yell and I'll try to accommodate.

[falconvan]

LS will fit on the stock frame,I've got one in my 48.

[Tim Keith]

I'm sure that you can fit the LS1 into the P15 better than in the F-body it came from - the motor is set back in the Firebird so that its difficult to access.

[Smokeybear]

LS will fit on the stock frame,I've got one in my 48.

Really, cool, you wouldn't happen to have any photo's and/or tips and tricks to share would you. I kinda figured it would shoehorn in, I looked at side view pictures of both engines and was hoping they would be close enough to be able to work. Did you build your own engine mounts? Which manifold/headers did you use? Did you use an auto or manual trans? Sorry for all the questions but you have my interest piqued. Thanks in advance.

[Jonnyz72]

 

Hi, I put a 318 & torque flight in my 47 Desoto. I made my own motor & transmission mounts, added a disk brake conversion but, used the original suspension & rear end. I'm currently rebuilding another steering gear box to replace the worn out one thats currently in the car. I posted some videos on youtube. you can find them by searching 1947 Desoto. my youtube name is jonzavrel. sorry I don't know how to share the link here. Good luck with your project!

[knuckleharley]

I say try the swap into your stock chassis first,and see what you have to deal with. If it looks like it's going to become too much work,you can always go to plan B.

 

It's mighty tough to go back to Plan A if you are already at Plan B or Plan C,though.

 

In general,I think it is always best to go with the quickest and easiest method that will get you what you want. No need to do work and spend money unnecessarily.

 

Who knows,you might get the engine and trans settled in,and after looking at it sitting there for a while,the solution to all the other problems will suddenly seem obvious to you?

 

Or even just decide to go with a inline with more power. You have all sorts of options until you cut the frame off or pull the body from the frame. Once you do either you are pretty much committed.

[falconvan]

Really, cool, you wouldn't happen to have any photo's and/or tips and tricks to share would you. I kinda figured it would shoehorn in, I looked at side view pictures of both engines and was hoping they would be close enough to be able to work. Did you build your own engine mounts? Which manifold/headers did you use? Did you use an auto or manual trans? Sorry for all the questions but you have my interest piqued. Thanks in advance.

If you look at my profile you can find the build thread on my 48 along with a ton of pictures. My LS is the 5.3 truck version. I built my own mounts and switched to a rack and pinion steering setup. As far as headers I bought a set of block hungers. For an intake I used a kit made by Edelbrock that coverts it over to a carburetor with an MSD ignition box and put in a ZO6 Corvette cam. Trans is a 700R4. The car is still in progress but its coming along; it's taken forever to finish the paint plus I keep getting sidetracked on other projects! Be glad to help you any way I can; the LS based motors are so much better options than the old traditional small block Chevys.