'77 4350 Spreadbore/Manifold Swap Replacing '78 2150 2bbl Question

[Ripper420]

So...This is my first ever post here on FSJN (go easy).
First, I just want to say that I live in Durango, CO and it's killing me that my 2150 2bbl is not letting me get to OURAY this weekend! Ouray is literally 45 minutes away from my house. I hope you guys can help? All the member posts and overall knowledge has already helped me rebuild/replace so much. I try to learn something new everyday from you guys. Thanks in advance!

I have 2 Cherokees:
-'78 WT 360ci, 2bbl that somehow lost some linkages and runs like s&^*t. It's trashed til a rebuild or replace.
-'77 NT 4D 360ci, 4bbl 4350 spreadbore that runs great, but needs TH400 work. It's not drive-able.

My question is: If I swap the manifold & carb from the '77 onto the 360 in the '78 is there any major issues that I will run into? They seem bolt for bolt.
Are there any tips you can give me to make the process smother and avoid pitfalls that would be time consuming? I.e. - Adjustments after install?
What emissions crap can I jettison?
I have limited knowledge with carb's/emissions and not afraid to admit it.

I love patching my FSJ's together last minute to get a trip going and the Ouray gathering seems to be the best excuse to hustle.

Thanks again, JW

[Tatsadasayago]

Right off the top of my head at this late hour, there are a few things I can suggest you watch out for.
Yes, the manifold will swap easy-peasy.
The throttle cable length and mount are different between the 2bbl and 4bbl but since you have both, you can swap them directly.
The 4350's fuel line connection is different than the 2BBL's but you can simply swap the hard lines from the donor engine so things line up...assuming the 4350's fuel lines are stock/original.
Vacuum lines and ports are different, so take a photo of each before tearing stuff apart.
I would seriously suggest you NOT pull the 4350 from the intake since it sounds like it's working good. The moment you crack the carb loose from that stupid phenolic spacer and manifold, you will have vacuum leaks...bet your life on it!
You may need to play with the ignition timing to get the new combo to play well with the engine.

That's all I can think of at this hour. Good luck and best wishes on making it to the event!

[Ripper420]

Awesome. Thank you Tatsa,
You are reading my mind. It's good to hear some confirmation on what I was assuming, and not pretending I know everything. That's when it hits the fan and I've learned that well in the past.
But,
-Good call on the throttle cable. That will save me some head scratching.
-The hard lines for fuel are stock and will swap.
-I know the vacuum lines shouldn't be that scary, there isn't that much going on there. But, once you F something up, it can be hard to retrace. I am not a fan of an oh-shight moment today.
-From everything I have read about the spreadbore is that maybe 8% of them don't have some kind of leak. I actually feel pretty blessed right now having one that operates. Once that original seal goes then you might as just Spend some $ and get a new manifold/carb or continue to be in denial like most AMC owners and try to fix the same problem over and over to save money and defy the odds. I think that is the definition of insanity, right? It's to much fun either way! Thanks again for your help and advice. I'll let you know how it goes!

[Tatsadasayago]

Yes, if you have a good working 4350, you have a rare critter indeed.
I had one once that worked perfectly...and performed every bit as good as the other 4BBLs but really shined on hills and angles. Very impressive wheeling carb.
I forgot to mention that many of the 70s FSJs used the same length throttle cable between the 2 and 4 bbls. You can confirm this by fully extending the cable (Closed throttle) and measuring the amount of exposed cable. Yours may be the same, which will save you some hassle.
Yeah, I've learned that the moment you begin to think you know it all is the moment where you learn that you don't.
Again, good luck!

[Nikkormat]

I've got four 2150 cores, a few good 4350's and manifolds, and a good th400's!

I can mail you a good 2150 that needs a power valve for real cheap. PM me if you're interested.

For now here's an inside look at the 4350: http://www.ifsja.org/forums/vb/showthread.php?t=80329

[Stuka]

The 4350 is kind of a love hate thing. The tiny primaries make for great low speed throttle response. However, the secondaries are gigantic. So you almost always bog some once they open. My '75 Cherokee came with one. I swapped it out for a performer Intake and carb and never looked back. Although the 4350 was better offroad, it never once caused the engine to load up.

But their main issue is warping, causing them to leak, as you noted.