360 build ????s

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Ok so maybe changing things up a bit. A buddy has a 360 block .040 over. Keith Black 107 Hyperutectic pistons with stock 360 rods. Full floating pins. I was told this would help raise the compression to roughly 9.5-1 possibly a little more?? Then I would still be using my J heads.

Thoughts on this application vs using the stock rotating motor previously mentioned?

Sounds like a good start .
If the price is right I would snap it up !
Best of luck !!
As far as budget , when you a good deal it more often then not is cheaper !!!
 
I thought you were on a budget, saving money for later. Am I in the wrong thread again?

You are in the correct thread. I just have a feeling this is going to spiral into something more and just take longer to build. Which is fine. Patience Patience patience. lol
 
Sounds like a good start .
If the price is right I would snap it up !
Best of luck !!
As far as budget , when you a good deal it more often then not is cheaper !!!


That is what I am trying to pencil out is a rough cost. I need to get the compression up from stock. So these pistons would be a good start. I can get the block pistons rods and crank for $250. Already have my heads. I have 273 adjustable rockers I could use or use as a trading tool for different rockers. Then the added costs of buying a the oil pump/pickup accessories, bearings, full gasket set(which will most likely do if I buy the stock motor), etc.

I currently have a 318 in the car. What all will swap over to the 360 from that? Rockers, push rods, timing cover???


Sorry for all the dancing around and confusing everyone. Just Learning a ton here.
 
$250 is a hard deal to pass up!
But, before you put money into that 360, have a look at how far down in the hole those pistons are,and check also to see if the piston tops have valve reliefs in them, or if they are plain flat-tops.Bring a piston to the top, exactly to the top,and measure with a precision measuring tool.With this figure and the head CCs, we can determine fairly closely your Scr. From that it becomes possible to juggle Dcrs and ICAs, to arrive at a cam choice that works for your available gas, and that meets your performance goals. With out the Scr, I, at least am blind, fumbling in the dark,just plain guessing.
For the 360; you will need to know if any balancing was done. If nothing else try to get the oem harmonic balancer. If no good answer come as to balancing,be prepared to have it done.
You will need; oilpump,pickup,A-body oilpan,Performance timing chain set,one engine bracket(drivers side I think),a 360 gasket set, and the cam kit.
You will be able to reuse the 273 arms(if in good shape), the timing cover, the cam T-plate,and everything else from the decks up.
We wont know about the pushrods until after mock-up.
This assumes the short block is otherwise complete including all new bearings and rings, etc.

Just in case you're not familiar;Scr is static compression ratio, Dcr is Dyamic compression ratio, and ICA is intake closing angle.
The measurement from the top of the piston to the deck surface is called Deck Height, and is measured in thousands of an inch(like feeler gauges) and the tool that does the measuring is a Vernier Caliper, or a Dial Caliper.
 
The pistons have .005 relief in them. When he disassembled the motor the pistons were .003-.004 below the deck. They are not flat tops. We are not sure on the cc of the heads but he said they seem close to what he is putting on his new motor and those are 70cc. Then he figured a .040 blue Felpro gasket. He figured up a 9.92-1 compression ratio. Idk how far down the pistons are, unless you meant below the deck. otherwise I have provided what I do know....

My next thing is. This block needs one cylinder sleeved. Machine shop said there is the risk to warping the next door cylinder when doing so. Thoughts on that route or should I just bore a different block and avoid the sleeving? All in all to get my compression ratio up I have a tally of roughly $1500. That is machine work, cam, gasket kit, high volume oil pump assembly, new rod bolts, buying his pistons/rods and block, new water and fuel pump. Still need to figure up a cost for bearings of course. So I am kind of spun on what to do. It is starting to get to the point of where do I say too much money and go with the 408 out of the gate.
 
Find a different machine shop.

So I was confused before, but now Im really lost. This 360 is assembled? But needs to be torn down to sleeve one cylinder? Or, What exactly does this $250 buy?

Going back to the teener, which seems to be running just fine,tho a little underpowered, right?
Seems to me, if you start the 408 project now,the short block will be done before winter(which around here starts in September). That gives you 3 to 4 months to get the rest of it sorted out, a month to assemble it, a month to install it, and a month to drool over it, and then its next spring.GO TIME!
I think I could suffer the teener a little longer. I know I could. Especially having a a $1500 fatter bank account.Ima thinking thats a real good start on a nice pair of heads.
Maybe use the money for rear-end upgrades. Like an 8.75,with 3.55s. Thats something the 408 will need anyway.Or brakes. You know you are gonna need brakes! Or go over the chassis and get it into shape. That 408 will need frame connectors, HD springs, HD brakes HD everything.Well you get the idea. If you start on the chassis now,then by fall, you will have her whipped into shape, and you will have been so busy that you wont even have noticed that the teener was lazy. This way everything will come together by next March, and you can enjoy the 408 ALL next summer.That 408 can get you into a whole heap of trouble in the blink of an eye.
Well, thats what I would do.
 
The machine work was going to cost $590. The setup that is .040 was all one at one time. He bought a Duster with the motor in it. He seen it run a 12.03. He pulled the motor just to paint it. Pulled the heads off to see how things looked the number 6 wrist pin came out and scored the piston. Lucky on the sellers part it didn't hooch IMO. Anyway, that one cylinder needs a sleeve($175). The rods resized($80) and new bolts (he recommends). The crank is already -.010 and looks good but he isn't for sure($125 if needs ground). Cam bearings look good also($35 if needed and the Mopar block doesn't give problems). He is a buddy and knows more than I do by far. So I trust him. He also said I can take it to a machine shop and ask them questions in person with he parts right there to get verification of what needs done. That is what the $250 gets me.
 
So it sounds like you have; 8 used 40over pistons(maybe 7), and maybe a crank. I would pass.


OK, thank you for the help. I appreciate everyones input! I am going to throttle back a bit and not pull any triggers yet.
 
You already have heads .
You might just look into a ready short block ?
Did you say you already have a stock 360 ?
There are plenty of places with good deals on rotating assemblies .
 
Damn, I would have been done already with this thing. Sure compression is good. But not if your going to let it make or break this build. Throw on a four barrel and an off the shelf XE268 or get a custom ground cam,and a high rise intake. A few suggested the Edelbrock RPM. It's a good one! You can even use it on 408 later. I'm a pretty patient person but even I am tired of hearing the same questions with different worded answers. AJ is spot on in his posts, listen to him. You will be more than happy. All in all you will have spent like what... 600 bucks? Sounds good to me.
 
taller pistons like the keith black are good to raise comp. ratio. 1971-2 360's had J heads. look at the 20-232-4 comp. cam, 2500-6000 280/280 230/230 .480"/.480" and 110 lsa. on a budget - for now use the carb, intake and gears u have
 
I am not throwing the build idea away. Just decided to slow my urge to jump into something. I decided to pass on the .040 over setup previously mentioned. That is what was going to cost me a ton of money.

The stock 360 I can buy for $400. He says it is a drop in and run type. If I go that route i do plan to use my J heads, intake, and carb for now. Those can always be upgraded later.

My main thing I have to do is study up more before making a move. Plus, it is easy to get caught up in the excitement of "building" a motor and having more power. Which can sometimes lead to a mistake. I don't want that.
 
Well, whatever you decide to do I'm sure it will be fine. Oh! And use a torque wrench! I'm sure you will I'm just throwing it out there. A guy I work with says he never uses a torque wrench cuz every time he tightens a bolt it's perfect. Obviously he is an idiot. So anyway I ask him so how do you know? He says he has checked with his torque wrench. If it calls for 40 pounds he tightens it by hand then checks it with his wrench. He says it clicks and is spot on every time. So I say, so you know it's still gonna click if you OVER tighten it right?..... So he stops to think about it for a second. Dumbest look on his face ever!
 
Well, whatever you decide to do I'm sure it will be fine. Oh! And use a torque wrench! I'm sure you will I'm just throwing it out there. A guy I work with says he never uses a torque wrench cuz every time he tightens a bolt it's perfect. Obviously he is an idiot. So anyway I ask him so how do you know? He says he has checked with his torque wrench. If it calls for 40 pounds he tightens it by hand then checks it with his wrench. He says it clicks and is spot on every time. So I say, so you know it's still gonna click if you OVER tighten it right?..... So he stops to think about it for a second. Dumbest look on his face ever!

Haha! Yes I will be using a torque wrench. 3 years ago and 8,000 miles I rebuilt my first motor.
A 440 in my 76 Powerwagon. I beat the crap out of that truck. The motor gets ran hard bout 75% of the time I am driving it. I call it luck but knock on wood it is still running. No smoke no ticks or rattles. :burnout:
 
Well for an update.

Some may disagree with my choice but I decided to stick with the 318 that is currently in the car. I know this motor is sound. It does not smoke rattle use oil or anything. Also this direction for the time being is friendly to my current budget and will still make a fun thumper to beat on. I am going to install the purple shaft 284/484 cam, use J heads, Torker II intake and most likely swap to a Holley carb.

My question this time around is. The 318 is a 78 setup. Does anyone know off hand if the pistons pass the block surface from the factory? ( Sorry for the lack of correct wording, positive???) Reason I ask is i dug into my heads some more. They have been milled .100. So obviously need to worry about piston to head/valve clearance. One positive thing is this will help raise my compression if I can still use these heads. I am only asking on here rather than looking for myself because I just found out the info on the heads this evening and do not have time till next week to tear the motor down to see.
 
You are getting ahead of yourself. At least, I, think you are.
Do not order that cam, or any cam, for that matter, until you get the heads off, and are able to calculate the Scr. That cam is too big for a low compression teener. Do not get caught up in cam hype. The single most important thing to consider on an existing combo is the ICA;the intake valve closing angle. If you get that too big, on your combo, your drive-ability will suffer. Not may suffer. Will suffer.
If you value off-the-line-punch, and cant afford a decent hi-stall TC, or 4.10 gears, just waitaminit.Get that Scr number, plug it into a good Dcr calculator. Play with it. It will spit out a number for you. That will be the ICA. Order your cam based mostly on that number and you will be playing to the strengths of the combo. Do do otherwise will lead you down a path of disappointment or endless money-spending.
 
You are getting ahead of yourself. At least, I, think you are.
Do not order that cam, or any cam, for that matter, until you get the heads off, and are able to calculate the Scr. That cam is too big for a low compression teener. Do not get caught up in cam hype. The single most important thing to consider on an existing combo is the ICA;the intake valve closing angle. If you get that too big, on your combo, your drive-ability will suffer. Not may suffer. Will suffer.
If you value off-the-line-punch, and cant afford a decent hi-stall TC, or 4.10 gears, just waitaminit.Get that Scr number, plug it into a good Dcr calculator. Play with it. It will spit out a number for you. That will be the ICA. Order your cam based mostly on that number and you will be playing to the strengths of the combo. Do do otherwise will lead you down a path of disappointment or endless money-spending.
Cutting the heads that much is going to change things a lot. He needs to figure out where he sits after that before worrying that it's going to be low compression. 11.5:1 with open chamber heads will be much worse than 8.5:1 if it's supposed to be a pump gas motor. It's much cheaper to buy a new cam if it doesn't work well than to have to deal with a heads/short block combo that doesn't match.

It's not all that uncommon for people to stay hung up so much on gaining compression that they forget there's such thing as too much. At least being after a real cam is going to help that some compared to trying to gain points of compression at a time and avoid even a stock 340 cam.
 
Well, I understand what you guys are saying. All that fine detailed info will help greatly when I build Bigger badder motor down the road(2-5yrs). This is just a cheap as I can fun 318 to beat on with the 4 speed and 4.11 gears. I understand I will lose the low end side with low compression and this cam. I also learned the gears and 4 speed will help compensate that a little. Now that I know the heads have been shaved and how much I am not too worried about compression being too low now. Just worried it may be too high. As long as the piston clearance is ok I am going to go forward with the build. I was just curious if anyone knew where the pistons set at TDC from the factory in relation to the block surface. Someone told me he thought they set .100 down in the cylinder at TDC. He wasn't 100% sure though. I will be checking that very closely before assembly. Also, curious if the stock length push rods will still work or if need shorter ones?

Again, I do NOT want to sound rude and/or arrogant by continue with my setup. I do appreciate all the info that has been provided. Just at the moment I am going to take the chance and sacrifice some sort of performance. This is just going to be a fun run around street thumper motor and a random track time setup. It may not be an ideal street friendly cam/setup but I know there are larger applications running around out there than this. The perfect motor combo will be built in the future and will slowly be done of years not a few days or weeks. haha

Thanks again!
 
Well, I played around with the Dcr calculator, and it turns out, you'll probably be allright; so long as the valves dont get into the pistons.
Unfortunately there may be very little to no quench or squish, so you may be stuck running premium, even though your Dcr is in the ballpark. Guess we'll see. Good luck
 
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