Cheepy Three-Sixty build

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RAMM

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I recently acquired a 360 block 'circa '73 so it is a very early 360. Well after walking around this block for a few days the wheels began turning in my head. What kind of build should this block be used for? What kind of parts do I have on hand that I wouldn't mind using up? Eventually the thought process evolved into a theme that could be guessed at by the thread title.
The plan in black and white is:
Build a VERY streetable/driveable pump gas 3.58" stroke 360
Use what I have on hand
Use inexpensive readily available parts new or used if I don't already have them
Use proven machining procedures/techniques as "ace up my sleeve"
Power output goal= 400HP @ 5800-6000 rpm 425+ TQ @ 4300-4500 rpm

Truth be told I really dig the cheap aspect and think it appeals to a large demographic here on FABO. Case in point , finished up a serious 436 W9 mill today--made big power/torque sounds absolutely obscene it also has a serious price tag. While it was fun it doesn't pique my interest like these "Bang for the Buck" scenarios.

To kick it off here's a pic of the cam card. A custom cam has no place here. J.Rob

Cheepycamcard.jpg
 
One of the earliest decisions in an engine build is the piston selection. This can be kinda tricky when your engine family has a scant piston selection and becomes even trickier when the compression heights offered are in the basement. Having a set of Sealed Power H405CP .020" on hand made this choice easy. Before decking a quick sonic test confirmed yet again that the "early 360's were cast with the 340 cores so the cylinder walls are extra thick" is a MYTH. While the cylinders were quite consistent they are no thicker than an average LA 318/340/360.
Zero deck--The math went like this:

Stroke 3.58/2=1.79
Rod Length =6.123
Comp HT =1.637
Zero deck =9.550

After decking the block height measured 9.549"-9.5495". The rods being used will be Magnum rods recon'd with ARP rod bolts so they will wind up .001-.002" shorter which puts the piston pretty close to zero deck. J.Rob

Cheepypistons.jpg


DeckingCheepy50.jpg
 
Forgot to mention that the mains were given a "lick" in the Line Hone and are right in the middle of the hi/lo spec. Also the cylinders were honed .020" to yield a piston to wall clearance of .0015-.002". I really like cast pistons for there stability. Some people may falsely believe that forged pistons make more power--they do NOT. J.Rob
 
I'm a real cheapskate when it comes to myself and have grown fond of this build so I know it will be paired with a 5spd manual trans which is why I like to perform this mod. Thrust failures are few and far between thankfully but with this modification can be completely eliminated. Just install thrust bearing and drill a .062" hole carefully through the rear face of the insert so that the hole intersects the main feed. Deburr and your done. The thrust face will look as though it never made contact after many many miles. J.Rob

Cheepythrust.jpg
 
As it sits the bottom end will be comprised of:
73' 360 .020"
Magnum '93 Con rods w/ARP bolts
H405CP.020 pistons @ zero deck
Cast crank .020/.020" balanced externally
Durabond cam bearings, King mains/rods
Crane H272-2 hyd flat tappet
Good t-chain (undecided)
M72 w/rear sump pick-up & pan

The top end will get interesting. I may utilize some stock Magnum head castings, fix the cracks with seat inserts, port them and use stock (cuz that's what I have on hand) G3 Hemi valves, springs, retainers, locks. I test fitted a 2.00" 1.55" G3 valve into the Magnum castings and they look right at home. Of course I need to look at spring pressures, lengths, etc..... I'm leaning towards some Comp 5/16" studs /guideplates and some steel roller tip rockers. Pretty sure I'm gonna go this way because I like to be different and I doubt its been done more than a few times. Of course a OEM Magnum head will dictate a Magnum manifold so likely a Cross-wind will top this project. J.Rob
 
It'll probably end up being a total nightmare for Mustangs.:D
"Oh, well it's just some parts I had lying around"
 
mderoy340 said:
I always enjoy reading your threads. Thanks for taking the time to share your knowledge and tips.
Click to expand...

I actually enjoy sharing with communities such as FABO, however if the incessant Ad B.S. doesn't ease up I will probably come around far less. Hate to say it but I don't really have the time it takes to post when Ad pop-ups slow my computer up even more than my already shitty internet service. J.Rob
 
TrailBeast said:
It'll probably end up being a total nightmare for Mustangs.:D
"Oh, well it's just some parts I had lying around"
Click to expand...

Funny you mention this--The very first engine I "rebuilt" was a 360 out of a Cordoba. Did a re-ring job and stuck a small purpleshaft in it with a Weiand Stealth manifold and a rebuilt TQ. That engine probably made all of 275-300HP but the 5.0 crowd ran and hid from my 71 Valiant. I think that's why I love 360's so much, they always had a rep of not being a revver like a 340 and having no power or the rods not staying in them when revved like a 340. I addressed all of these issues with my first 360 and the only thing in town in the street small block crowd that had anything for me was a rebuilt 340 powered 4spd Dart--even then I killed him off the line and we were neck and neck the entire quarter. Stop light 2 stop light it was no contest. Properly built 360's kick the sh#$ out of 340's on the street. J.Rob
 
Do you own your own machine shop, or work at one?
Just wondering, things like boring for oversized pistons, line honing, decking the block, roller tip rockers are all things that don't go along with a "cheepy" build. At least not in my budget.
I know you said you already had a bunch of stuff lying around, but machine shop time ain't cheap.

Anyway, best of luck on it. What's it going into anyway?
 
MileHighDart said:
Do you own your own machine shop, or work at one?
Just wondering, things like boring for oversized pistons, line honing, decking the block, roller tip rockers are all things that don't go along with a "cheepy" build. At least not in my budget.
I know you said you already had a bunch of stuff lying around, but machine shop time ain't cheap.

Anyway, best of luck on it. What's it going into anyway?
Click to expand...

Yes I have a machine shop. I guess your version of cheap is a little less than mine-lol. My parts list is as cheap as it gets. Maybe you think cheap is re-using everything but rings and gaskets--See my post #11.

My comment of "Ace up my sleeve" was in reference to being able to make up in machining where the racy parts lacked. Also when I said roller tip rockers I picture Comp's budget Chev style steel roller tip rockers. Like this --https://www.summitracing.com/int/parts/cca-1417-16/overview/


Heck who know's ? Maybe I will use a set of "full boogie" Comp Hi-energy die -cast roller rockers. Going in a truck. J.Rob
 
RAMM said:
I actually enjoy sharing with communities such as FABO, however if the incessant Ad B.S. doesn't ease up I will probably come around far less. Hate to say it but I don't really have the time it takes to post when Ad pop-ups slow my computer up even more than my already shitty internet service. J.Rob
Click to expand...


I don't get pop up ads. Is it a Canada thing of just the IP?
 
MileHighDart said:
Just wondering, things like boring for oversized pistons, line honing, decking the block, roller tip rockers are all things that don't go along with a "cheepy" build. At least not in my budget.
Click to expand...
FWIW:
- You can save the decking cost by going to H116CP pistons in an undecked block, and will end up at the SCR with the same heads and head gaskets. The H116CP's cost $170 more than the H405CP at Summit.
- Line honing is an option in my book: If the crank installs and spins free, I have never had any issues personally, even cranking high revs.
- I don't bother with a rebuild without fresh bores; bore quality is the foundation of a good performing engine; even moreso at these power and torque levels.
 
nm9stheham said:
FWIW:
- You can save the decking cost by going to H116CP pistons in an undecked block, and will end up at the SCR with the same heads and head gaskets. The H116CP's cost $170 more than the H405CP at Summit.
- Line honing is an option in my book: If the crank installs and spins free, I have never had any issues personally, even cranking high revs.
- I don't bother with a rebuild without fresh bores; bore quality is the foundation of a good performing engine; even moreso at these power and torque levels.
Click to expand...

The H116CP is a real nice piston and would have been what I went with had I not already had these 405's sitting on the shelf. When the main bores were checked three out of five were .0005" under the minimum. I didn't want to get this on the stand, install the crank and find out I had to take it back off for a line hone. Fresh bores are a must if the engine is to stand a chance of performing well. J.Rob
 
RAMM said:
Fresh bores are a must if the engine is to stand a chance of performing well. J.Rob
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Speaking of putting my money where my mouth is..... I just realized that the last time I did not pay for fresh bores in a block was 1980, in a 292 V8 for a 1960 Ford 1 ton truck.... LOL
 
Not everything needs a line hone, period, that was even addressed in a certain 340 build thread recently.....now that's out of the way...back to more interesting stuff, like the rest of this build and the numbers yielded.
 
I realize you have the pistons already. But for others, there are some soon to be discontinued choices still available. These are variations of the H116cp piston (which is the most expensive of these) There is a H116CPX also and a H116CPY. The differences are the compression distances. The H116CP is the tallest the H116CPY in the middle and the H116CPX the shortest. But the "X" and "Y" are much cheaper!
 
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Max1196 said:
I realize you have the pistons already. But for others, there are some soon to be discontinued choices still available. These are variations of the H116cp piston (which is the most expensive of these) There is a H116CPX also and a H116CPY. The differences are the compression distances. The H116CP is the tallest the H116CPY in the middle and the H116CPX the shortest. But the "X" and "Y" are much cheaper!
Click to expand...

I did not know this, thanks. J.Rob
 
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