Starting my parts gathering

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Fishthatkills

Fishthatkills

Fish that kills
Joined
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So I have a complete 318 engine and I am begining to gather and research parts for a small block build. I have read and heard that a 273 crank would be a good choice as they are forged and the same stroke and main journal size. I am not wanting or needing to stroke this thing out!
I have a lock on a 273 crank and rods for basically free, out of a running motor! Free is always good.

My current engine in the fish is a 273! So my plan is to have the 318 block gone through and over bored .030 over, using the 273 crank and rods. So what are good pistons? I will either be using stock 318 heads with mild porting or Edelbrock performer aluminum heads, if I can justify to the wife the expense!!!

I want as much horse power as I can get but really reliability is also a big factor. I think with the right cam and head work,intake and carb I can get 400 hp. Is that possible? not looking for a strip machine, just a Honda killer and street cruiser!

Thanks,
John B.
 
The 273 Steel crank and rods are a good starting place but remember free generally means they will need gone over. In fact it's just about as cheap to buy new Eagle or SCAT I-beams as it is to get ARP bolts put in old rods and have them re-sized which I can almost guarantee you need to do to 43+ year old rods to stand up to 400 hp. KB Hyperutectic (sp?) pistons are fine for a 3.31 stroke. Their pretty cheap too. Just remember to have the rotating assembly balanced no matter what route you take because the 273 crank is balanced for the bob weight of a 273.

400 hp is doable on a "teen" but you will sacrifice drivability. I doubt your stock heads even with mild porting will make much more than 300 hp. You will need to step up there if 400 hp is your goal. A lower cost alternative set of heads that can make 400 hp on a 318 are the RHS heads. Brian @ IMM engines (member OU812) sells them mildly ported and set up to go with good beehive springs for about the same cost as out of the box Edelbrocks and from everything I've read they out perform the out of the box Edelbrocks. Don't get me wrong, the Eddy's are great heads once you correct the sloppy valve job and check and ream the valve guides so you don't hang a valve open. Their quality control needs to be better. Even with Eddy's you'd need to do some porting to get 400 hp. I believe with the right cam (solid preferably) the RHS heads can make 400 hp on a 318. But along with that you'll need to run a pretty loose converter and low gears or it'll be a pig out of the hole.

You said you didn't want to stroke it but you may want to set down and figure up the price to do it as a 318 vs. a stroker. I say that because you may be able to find a stroker kit just as cheap as it'll cost to build the 318 due to all the machining expense of re-using old parts. Another big advantage is a stroker makes so much more torque than a 318 it won't need nearly as much stall speed and low gears (can we say drivability). Plus it'll be much more docile than a 400 hp 318. Just a thought to consider.
 
I agree with my central Il neighbor, look long and hard at a stroker, and if thats not doable i would go with a 360, don't worry about the cast crank in the 360 they can handle 450hp and even more.
 
How much are you willing to spend?

On my 318, I'm using the stock bottom end, (crank, rods, pistons) I just honed the cylinders, installed new rings and bearings, added a MP windage tray utilizing the stock passenger car oil pan. For a cam I used the Edelbrock Performer RPM cam and lifters (not the best choice, but it's all I had and didn't want to buy a new cam). I used a comp cams timing chain with a magnum engine timing chain tensioner.

For the top end, I didn't skimp out. I went with a set of RHS heads complete from Brian at IMM Engines. I had to do this to get my compression up to about 8.85 to 1. lol I went with a set of Hughes 1.5 roller rockers and an Edelbrock Performer RPM manifold with a Holley 600 spreadbore on top. I also am using the MP viscous fan package to free up some horse power. This combo should all be good for about 325 HP maybe a little more. My limiting factors are my low compression and the edelbrock cam...

I'm using 355 gears with a 3000 stall 11" converter from PTC.
 
Thanks for the feedback! As far as how much do I want to spend, well as little as possible, but the truth is I would rather spend the money on the right things and get a good motor in the end. I read the article in Mopar Muscle when they squeezed out 400 hp from a teen, I am not saying I can do that , I just want as much as I can get with out exotic parts and pain!!!

So spending the money on good machine work and heads would benefit me more than going stroker, but it's all relative really. No more than 3k total is what I am looking for. Like I said not going drag racing, just a sweet cruiser that can take a Honda when she feels like it.

I have read the stories on this board about the Eddy heads, and I have also heard that the RHS stuff is pretty good. So here is another question, What would get me to 9.0 compression ratio and still be street friendly and run pump gas, The commando 273 was 10:1 comp and 235 hp! So 300 to 375 could be possible? again with the right cam, heads and such!

318 stock block, squared to the world and .030 over, zero decked as a starting point. All other parts are the question?

John B.
 
can you use 318 rods with 273 crank? I have same build going on right now...shop has my 273 crank and my 318 block..and my 318 rods...Do I need to get them the 273 rods and not use the 318 rods
 
Furydan,
I don't know really, I just read that the 273 rods were stout enough, But then it's all in who you ask! I will have both at my disposal. I do believe they have the same journal size! Difference in the 273 vs 318 is bore size?

John b.
 
I guess I need to call the machine shop and ask them...maybe they could tell me. I too have both sets of rods at my disposal.
 
Some 318 engines were forgings with bushed rods for floating wrist pins. Casting numbers on 273 & early 318 should be the same. The 273 & 318 cranks have the same ballance. Early 273 has a smaller hub bore for torqueconverter hub.
 
i have a 318 a friend built for me, that runs a 318 block with 273 crank, 360 rods, 340 cam. a set of old 273 4 bbl heads (closed chambers to get up comp.) and performer 318/360 intake eddy 600 carb. great set up. strong as hell! almost everything was pulled out of the junk yard, super cheap. good luck with your build. alot of guys on here will tell you, you have buy expensive parts to make power. it is true to an extent but you can make a strong little a body for cheap as hell with the right info. there is a book out there called "chrysler performance upgrades" that will give you a world of info cheap.
good luck
 
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