318 vs 360 Rebuild...

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70DusterBob

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I'm starting with a 360 that needs to be rebuilt. '75 make. I have heard that a 360 block from 88 down will work. Is that right?

Anyway, if I can't find a 360 block, I'm sure the 340 long blocks are expensive, anyone got a ball park on a stock 340 long block?

I may need to find a 360 block, this one is at 60 over already, if it is too worn for honing, I will need to find another bock, if I can't find another block, I may need to go with a 318. I am planning to port the heads and get a large hydraulic roller cam for which ever one I end up with.

If I can't find an empty 360 block, I will probably have to get a completely rebuildable long block 318 or 360.

I know the list is long, but can someone give me an idea of the "basic" pro's and con's of having a 318 vs a 360 and vice versa? For example: I have heard the 318 is quicker off the line, and the 360 is more for top end.

A 318 might be easier to find, I don't know.

Do I have any other options I am not aware of?
 
You will need to change the balance between the two.........different balancer, different converter / flywheel. Pans are different if you are talking about LA and not magnum. LA 360, the rear pan seal area is much smaller than a 318. If you put 360 heads on a 318, you lower the compression A BUNCH. Most 318 heads have much smaller ports. Most of the rest you can deal with
 
360 LA engine went up to 1992......

360 Magnum continued to 2002....
 
Why not just het a 5.9 Magnum . They come factory with a roller cam. They tend to have much less cylinder bore wear because of the fuel injection help with better fuel control. Less of a tendency to wash off the cylinder wall oil. They are more plentiful now than the other LA engines as those have been out of production for over 25 years now. Aftermarket Magnum heads are plentiful and economically priced. Competitive with any 318-360 cylinder heads. More power potential with the swirl combustion chambers than the 318-360. Shortly the Gen III engines will dominate the wrecking yards and will be like the next SBC of engine transplants.
 
Thanks, I swapped from a 318 to the 360 20 years ago, couldn't remember all the differences but knew there were some.

The machine shop said it was '88 and down, upping the search to '92 may prove helpful. Yes it is an LA.

Can I put an Air Gap Eddie with a Holley on top with the Magnum? I like carbs.






360 LA engine went up to 1992......

360 Magnum continued to 2002....
 
yes..just buy a eddy air gap for a magnum ......
 
Thanks, I swapped from a 318 to the 360 20 years ago, couldn't remember all the differences but knew there were some.

The machine shop said it was '88 and down, upping the search to '92 may prove helpful. Yes it is an LA.

Can I put an Air Gap Eddie with a Holley on top with the Magnum? I prefer the carb set up. 30 years of messing with them and I almost have them down, lol
 
Yes. the intake bolt angle is different but the pattern is exactly the same. Very simple to adapt.

Do I just need to drill the holes out a bit, maybe 1/16"? I just bought the air gap and found metal in the oil.
 
O-M-G!

Slow down there champ! The post looks like a teenager babbling on while stoned, ... and overly excited!
LMAO, I’m goona answer your questions one by one but what I need from you is to settle down and think of a route to take after you read my post answers.

I'm starting with a 360 that needs to be rebuilt. '75 make. I have heard that a 360 block from 88 down will work. Is that right?
If the ‘75 isn’t a good candidate to rebuild, ANY 360 is fine to use.

Anyway, if I can't find a 360 block, I'm sure the 340 long blocks are expensive, anyone got a ball park on a stock 340 long block?
I don’t think anybody can ball park a short block built for you because prices change from machinist to machinist, area to area, state to state.

But! A 360 block can be cheap as $100 and a 340 block can be around $600-&700 bucks or more. Also the piston choice can vary a lot because the 340 can have a larger bore way past a .060 IF the core is good. That adds cost. And a good chunk.

If I can't find an empty 360 block, I will probably have to get a completely rebuildable long block 318 or 360.
Stick with the 360 because the 318 has a sub 4.00 bore which equals more money in pistons. ( usually )

I know the list is long, but can someone give me an idea of the "basic" pro's and con's of having a 318 vs a 360 and vice versa? For example: I have heard the 318 is quicker off the line, and the 360 is more for top end.
I don’t know who told you that **** but shoot them on my behalf so the world can be a better place with less stupid people in it. Thank you.
Both are about the same price to build except the 318. Pistons can be more expensive. Method of balancing can be an issue and add cost if you start moving away from stock methods.
The 318 is 42 cubes smaller. “42!”

The ability to rev is controlled by 3 things, camshaft profile, adequate spring pressure to control the valves, proper fuel and spark management (state of tune)

A 318 might be easier to find, I don't know.
Probably, but not by much.

Do I have any other options I am not aware of?
You can purchase a crate engine. Check out blueprint engines, we have a member here from Blue Print that posts on a regular basis. And/or ATK.

If you still want to build your own engine, you can add in a stroker kit for not much more of a standard rebuild. You can click on the Hughesengines banner above and check out there stroker packages for what ever block you get. (Except the 273.)
 
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the 89 to 92 360 could be factory roller cam to and they ran tbi so bores should be just as pretty! should have 308 heads as well and that and a bad platform to build from!
 
Do I just need to drill the holes out a bit, maybe 1/16"? I just bought the air gap and found metal in the oil.
Late Magnum engines do not have the ability as cast to oil the valve train as the earlier engines do, via, through the block up through the head to the rocker arm shaft. You’ll have to work around that.
 
the 89 to 92 360 could be factory roller cam to and they ran tbi so bores should be just as pretty! should have 308 heads as well and that and a bad platform to build from!
The 308’s are excellent factory stock heads if there found to be sound around the valves and great for porting.
 
O-M-G!

Slow down there champ! The post looks like a teenager babbling on while stoned, ... and overly excited!
LMAO, I’m goons answer your questions one by one but what I need from you is to settle down and think of a route to take after you read my post answers.


If the ‘75 isn’t a good candidate to rebuild, ANY 360 is fine to use.


I don’t think anybody can ball park a short block built for you because prices change from machinist to machinist, area to area, state to state.

But! A 360 block can be cheap as $100 and a 340 block can be around $600-&700 bucks or more. Also the piston choice can vary a lot because the 340 can have a larger bore way past a .060 IF the core is good. That adds cost. And a good chunk.


Stick with the 360 because the 318 has a sub 4.00 bore which equals more money.


I don’t know who told you that **** but shoot them on my behalf so the world can be a better place with less stupid people in it. Thank you.
Mbofh are about the same price to build except 318 pistons can be more expensive. Method of balancing can be an issue and add cost if you start moving away from stock methods.
The 318 is 42 cubes smaller. “42!”

The ability to rev is controlled by 3 things, camshaft profile, adequate spring pressure to control the valves, proper fuel and spark management (state of tune)


Probably, but not by much.


You can purchase a crate engine. Check out blueprint engines, we have a member here from Blue Print that posts on a regular basis. And/or ATK.

If you still want to build your own engine, you can add in a stroker kit for not much more of a standard rebuild. You can click on the Hughesengines banner above and check out there stroker packages for what ever block you get. (Except the 273.)

LOL Rob, I haven't been called an excited teenager in,...... hmmmmmm, 35 years, lmao.

I am somewhat excited to be rebuilding this engine. I am glad to have this forum that can give me the information I need to do it right. This place is priceless if you think about it.

I've got a bad case of arthritis in my back preventing me from any heavy lifting or the heavier work, but I do have a good mechanic that can do it, per my instructions. I figured the 340's were expensive since they are so sought after, that and they are rare too.

I appreciate your advice, and will try to stick to the 360 since there are so many balancer/balance issues with it. 42 Cubes would be noticeable.

I will look into a crate engine, but was thinking that if I were to get one it would not have a large cam in it and I would void my warranty by tearing it up. Is that right?
 
there are no balancer/balance issues with a 360.....just use the right one.....simple
 
there are no balancer/balance issues with a 360.....just use the right one.....simple

I mean switching between the 360 LA that is in it now and going to a 318 would mean a different converter, flywheel, balancer.

I found BluePrintEngines and convo'ed them. I will see what they have to offer and for how much.

Thanks
 
True! The balance issue is when you move away from what the factory did. It will add costs going from external to internal.

The Magnum has a different external balance than the LA 360 external balance. The good news is B&M has a SFI flex plate that handles both engines.

I don’t know how big of a cam you want to run but Blue Print does offer 2 different cams with the engines. Go to Blue Print (.com) Has a good street cam and the other is about 10*’s more. For a nice street stripper that isn’t to danm big to drive around on.
Swapping out a cam is no biggie. Re sell the cam (the cam that comes in the BP engine) to off set costs if not simply break even. (Or better yet, profit!)

Oh, arthritis, yes I got it, I know it.
 
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True! The balance issue is when you move away from what the factory did. It will add costs going from external to internal.

The Magnum has a different external balance than the LA 360 external balance. The good news is B&M has a SFI flex plate that handles both engines.

I don’t know how big of a cam you want to run but Blue Print does offer 2 different cams with the engines. Go to our Print (.com) One is a good attested and the other is about 10*’s more. For a nice street stripper that isn’t to danm big to drive around on.
Mswapping out a cammis no biggie. Re sell the. p cam to off set costs if not simply break even. (Or better yet, profit!)

Oh, arthritis, yes I got it, I know it.

Hey Rob, I will go check out the site now. Just wondering what you meant by "Re sell the. p cam" to off set costs. Was that a typo?

I will go see what bp has to offer.
 
Left side motor mount is different from 318 to 340 & 360. Some guys have made the left one work by adding shims to take up space. I went to Carlisle over the summer and picked up the correct mounts. Shumacher makes them but a little pricey but is worth the assurance of using the right mount.
 
One thing I like about 360s especially for the street,is that when you put tall flat-tops in them (like the KB 107/191s or similar),you instantly have some compression to work with. And the biggest part of that is the 740/750 or more CCs of swept volume. It is a lot easier/cheaper to get to 10/1 or more Scr, with a 360. And when you get there, you can put some cam into it and still have enough bottom end to not have to run a big TC or race gears to get moving. That close-to-zero deck gives you a lot of flexibility in choosing the top-end. Flexibility that you can use to tailor the engine to your needs and/or expectations.
 
Hey Rob, I will go check out the site now. Just wondering what you meant by "Re sell the. p cam" to off set costs. Was that a typo?

I will go see what bp has to offer.
Fixed it above. I was saying to resell the cam that comes with the engine IF it is t big enough for you.

BluePrint Engines 408CI Stroker Crate Engine | Small Block Chrysler Style | Longblock | Iron Heads | Flat Tappet Cam

Looks good to me! And this will match all my pre-existing equipment, ie: headers, trans, TC, Flex Plate, motor mounts? And my brand new air gap? lol
What I was thinking about.....
BluePrint Engines 408CI Stroker Crate Engine | Small Block Chrysler Style | Longblock | Aluminum Heads | Flat Tappet Cam

The cam differences;

The first listed engine;
  • Cam Type: Flat Tappet
    .474 Intake .474 Exhaust
    238 Intake / 238 Exhaust duration
    @ .050 - 110 degree lobe separation
The second engine I listed
  • Cam Type: Flat Tappet
    .545 Intake .545 Exhaust
    241 Intake / 247 Exhaust duration
    @ .050 - 110 degree lobe separation
It’s only a few degrees difference but that can be the world sometimes. Ether way, if the cam isn’t large enough for you, then you could sell that cam and install your own.

The second cam is a Comp Cam XE.
The first cam has specs like the MP Purple cam.
Both will produce some good power.

Do note that the engines have two different cylinder heads. The bigger cam has Edelbrock heads where it can take advantage of the higher flow rates with the higher lift of the cam. Equaling more HP but a nice chunk.

Add higher ratio rockers and ported heads for more top end pop!
 
Looks good to me! And this will match all my pre-existing equipment, ie: headers, trans, TC, Flex Plate, motor mounts? And my brand new air gap? lol
Get with BP on the exact parts needed and let them know exactly what you have and what you want to do. They can just about sew this up for you.

The engine link you have pictured has Magnum heads. So the LA intake can not be readily used. Ask BP what aluminum head style is used on the other engine.I see an LA head pictured but it should be asked! As to avoid headaches!
 
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