UPGRADE A 318

[rumblefish360]

Valve train issues being swapping to the stud rockers, different pushrods and lifters. Mags oil through the pushrods like chebby.

Oh! I thought issues like what you would find on the Magnum valve train at a high rpm. At the point of where a griddle would be installed. Being that oiling is like the Chevy, the hollow pushrods are often a normal purchase since pushrod length changes when you start changing everything else on the engine. Milling decks and head surfaces are the big ones of course. Cam lobe size, lifters, even if both are the same cam family/engine family, the size of the lobe can be an issue, new rocker gear, all change the pushrod length. Pushrod length should always be checked. The placement of the lifters plunger changes from manufacturer to manufacture as well as simply part numbers from the same manufacture. Also the style of lifter, Hyd, solid & the same for both of the roller tappets.

Oiling through the pushrod (possibly) eliminates drilling the block for proper oiling volume to feed the rocker shaft and rockers. Oil going directly to the rocker isn’t a bad thing. In this manor, it helps eliminate high rpm oiling issues up top. Then you can focus in on getting the crank to live.

 

[72redbird]

Not sure how crazy you want to go. If you want to stay stock, what I did on my 72 Challenger was kept the stock pistons, installed a set of cylinder heads that had the heart shaped combustion chamber. Installed the stock 1968 340, 4 speed cam, LD340 intake, a carter 650 cfm carb, and put duel exhaust on it with the factory manifolds, also put the light springs in the distributor. Car had 3.23 gears, actually ran pretty hard for a 318! Best pass up here at 6500+ feet was 15.92et. Didn't have much in it, but this has been awhile back!

 

[Mark Barnes]

Interesting thread. I have a rebuilt 318 Magnum with less than 10K miles, a freshly rebuilt 273 with 1 hr of run time, and a newly rebuilt 904 trans.
Any chance I could make a fun combo with any of these parts?
I am pretty unfamiliar with the differences between the earlier 318's and the later Magnums.

 

[Slap Stick]

If you have a 273 then you know about 318 LAs pretty much.

 

[Mark Barnes]

If you have a 273 then you know about 318 LAs pretty much.

I guess my question is would there be any benefit from putting the 273 heads on the 318 block? The 273 has been kind of a PITA anyway...

 

[Slap Stick]

No. And there are differences in the heads and intake between early and late 273s IIRC.

 

[toolmanmike]

Yeah?
Is that YOUR port work? Looks pretty!

Yes, those are my 273 heads. A friend of mine did them. He works part time at a Mopar Performance shop nearby. They specialize in Mopar heads. Radar the shop owner used to do head work for John Force.

 

[Darter6]

I like mine. Just enough to sound good and give it some extra go with minimal cash outlay.

 

[Darter6]

Toolman,, Moar?

 

[toolmanmike]

Toolman,, Moar?

Nothing fancy.

 

[Darter6]

Nice !

 

[barbee6043]

Drop in a 3:5 or 3:91 and feel the wow even as is now.!

 

[dart4forte]

No. And there are differences in the heads and intake between early and late 273s IIRC.

Actuall the 920 is the 273 head you want to use. They flow a bit better than the other heads found on 273s. Another good head is the 302 swirl port.

 

[toolmanmike]

No. And there are differences in the heads and intake between early and late 273s IIRC.

64 and 65 273 heads are different. The intakes have smaller bolts and are almost 90° to the gasket surface. The chambers and ports are all very similar between the 64-67 273 heads. In 68 and 69 273 heads got open chamber heads that they shared with the new LA 318.

 

[Slap Stick]

Thank you, an old dog can still learn.
When I was messing with this stuff we didnt have this electronic library called the Internet.

 

[Ironbuilt]

Edelbrock makes a complete top-end kit for Chrysler small blocks. Guaranteed HP increase.

https://www.jegs.com/i/Edelbrock/35...m_term=4579397212211329&utm_content=Edelbrock

 

[VitaMeVas]

One of these days, I am going to do something with that 318 I have on the engine stand.
I've read about the 4 inch stroke crank builds...a 390 cubic inch plant that looks like a 318. Even staying stock stoke but a .030 bore to clean it up, stepping it up to true 9.5 compression, a cam at least as big as a stock 340 cam could really wake it up.
Ford and GM have been making power with their lower displacement V8s. The Ford 5.0 was a dragstrip winner for years. There is no reason why a 318 couldn't be built to be competitive.
Just look at the similarities and differences between the 318 and the 340.
Both have the same stroke but the 340 has a bigger bore to get the extra 22 inches.
The 340 had more compression, better heads, a bigger cam, larger carburetor and better exhaust manifolds with dual exhaust.
If you built a 318 to 340 specs, there is no logical explanation as to why you couldn't make a big improvement over the 150 hp rating that the 318 2 barrel engine had.

I bought a 68 Satellite with the original 318 bored/ stroked to 390 with more aggressive cam and ported heads. HP around 400-450. Impressive little V8. Lots of potential.