Engine Swap Qs, '87 burb to '83 K5

[yakmastermax]

Hey all

A while back I spun a main bearing in the 305 in my K5. Ran her low on oil

I've finally got the funds to get her running again. I found a guy on CL who has a 350 he's willing to install. Before we go ahead with the swap though I wanted to ask the brotherhood some questions and confirm the fitment of the motor.

The guy says that he went to the GM dealership about 3 years ago and got a crate motor replacement motor for his 1987 TBI suburban. I called the dealership and they gave me two possible part numbers for the motor: 12568758 or 12520270

http://www.jegs.com/i/GM-Performance/809/12568758/10002/-1

http://www.jegs.com/i/GM-Performance/809/12520270/10002/-1

We're planning to complete the swap over the course of next Saturday and Sunday so we should have 2 full days and he lives 10 minutes from an O'reillys.

I've figured out so far that my '83 spreadbore manifold won't bolt to the late '87-'95 style heads but I've found an intake manifold locally that should work. They guys says it is a knock off edelbrock (has no brand on it) with slotted bolt holes so it can bolt to the later heads but it is setup for a spreadbore quadrajet. Does this seem like an okay solution to get my quadrajet on top of everything? Should I consider using spreadbore to squarebore adapter instead and running a real manifold? If I go with the no brand slotted manifold what kind of gaskets should I get? I think the "no name" manifold may be a Professional Products manifold.

What all do I need to have planned for the swap? Will my exhaust manifolds bolt up? Will the existing motormounts work? Will the existing accessories bolt up? Will the Mechanical fuel pump from my 305 bolt up or do I have to get an electric inline system setup? What else should I plan for?

This is my first motor swap sorry for all the questions...

My truck is a 1983 K5 blazer, factory 305 and SM465 & NP208C

Thanks for the advice everyone!
I'm excited to get her running again.

 

[Kay86K5]

I would try to get the factory style TBI intake manifold, then just get an adapter to bolt on top to make your carb work. Will be probably easier that way. If 87 block, then motor mounts are the same, if I remember correctly, I think stock horn shaped exhaust manifolds should work, but can't remember if there was a generation change between those years (since the heads are different on TBI, there is a chance that there is a difference, but can't remember). '87 and '88 were still V-belt drive accessories (didn't change to serp setup until '89) so you should be fine there. For fuel pump, I would make the change to an inline electric one right now. Will probably save you a lot of headache and be easier. My brother swapped to that on his '78 from high school cause his mechanical pump was giving him so much problems. Everything ran a lot smoother after that.

That is all I can think of. Hope it helps. I just swapped out a carbed 383 to a TBI350 in my 86 K5. Everything was really easy other than the wiring. But since you are staying with carb, should go relatively smoothly

 

[yakmastermax]

I don't really like the idea of adapting the TBI intake manifold to the spreadbore quadrajet. Seems a little restrictive, thanks for the idea though!

I ended up picking up this intake manifold from craigslist:

It looks like a professional products intake manifold or possibly a knock off. I've ordered a set of the angled adapter bushings so that the manifold will seal well with the later style heads.

Motors mounts are the same check

Still not sure on exhaust manifolds, hopefully my '83 ones will work.

Belt and accessory drive is the same check

Definitely going with an electric inline. Anyone have any recommendations for a pump and how to mount it?

I'm afraid I've stumbled upon another hiccup. My '83 is a two piece rear main seal and the older style crankshaft. The flywheel that is in the truck now won't work with the new motor's crankshaft.

Anyone know of a solution? The parts store recommended buying an '87 flywheel and clutch kit for a 4spd TBI K5

Thanks all! I've got one week till the swap.

 

[yakmastermax]

Anymore Input guys?

 

[dyeager535]

No solution I'm aware of for the clutch but to get the one piece components. The seal is way better, still worth the expense/hassle.

I assume the cam doesn't have a fuel pump lobe? Have you checked?

 

[yakmastermax]

No fuel pump lobe so electric pump it is. Any recommendations for a pump or guidelines to installs?

Yeah I went to the parts store and they're saying I'll need the newer flywheel and clutch kit. The bellhousing and tranny should alll work fine though.

Anything else I am missing?