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Bone stock 360 potential?

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PHAT69AMX View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2019 at 1:46pm
Thanks everyone.
The 304/360 Crank in the 343 block with .020 shorter cast aftermarket 360 pistons
just happens to work out just right for about 0.000 deck clearance nominal
since the stock 343 was .060 nominal deck + .020 shorter slugs = .080 Deck
and 3.44 stroke - 3.28 stroke = .016 Stroke / .080 Throw...
If a 360 block, 0.000 deck can be accomplished with Deck Mill
which also ensures Deck square and true to Crank Centerline.


Edited by PHAT69AMX - Feb/18/2019 at 1:52pm
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Post Options Post Options   Thanks (1) Thanks(1)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2019 at 2:37pm
New +.030 Badger Cast Pistons and ~$1,700 paid a shop 1st build in ~1988.
Apart, "freshened", "tweaked", and self re-assembled 2 or 3 more times 1990-2007.
Always same bore, spun #5 Rod Brg ~2002, my fault, 6k+ shift points.
Denial, kept driving it, Badger Cast 360 piston eventually smacked the head
once the Rod Cap offset ground the crank far enough to allow contact.
Badger cast slugs replaced with same size +.030 Zollner Cast Slugs, Hastings Rings.
Around 50k street strip miles on that motor over 25+ years...
And it is STILL in the car and thumpin' right along for the new owner.
Still runs 12-sumthin', he had it at GAD 2017 and maybe 2018.
Endurance?... it went down the track a few times over that period of time...



 




Edited by PHAT69AMX - Feb/18/2019 at 9:42pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 1982AMCConcord Quote  Post ReplyReply Direct Link To This Post Posted: Feb/19/2019 at 7:54am
Wow Phat... that's a really good time. So.. flywheel hp would probably be around 325hp roughly? That's really good. Definitely fast enough for my car! 

So that engine was built with the old Badger pistons? What was the comp. ratio for those? 
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Post Options Post Options   Thanks (1) Thanks(1)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/19/2019 at 7:06pm
I guess flywheel HP would be about that, depends what "HP Loss % Factor" is used.
311 HP Flywheel results from 10% loss and 280 RWHP
375 HP Flywheel results from 20% loss and 300 RWHP

The 277-282 HP Chassis Dyno printout was before the mild ported big $ '70 Heads
and still had Badger Slugs, stock-ish '70 Heads, 3.44 Stroke, 365 CI, and 9.07:1 CR.
imho the 727 uses quite a bit of HP, and the Cheap B&M Converter is in-efficient, so 10-20% loss?

343-348-365-367 Compression Ratio "History" = 10.2:1, 7.8:1, 9.07:1, 9.68:1, 10.17:1

In about 1988 when I paid a shop to do the 1st rebuild on the original ~95k mile
stock 1969 343 4V 10.2:1 from my AMX I bought July 1985, and knew less than a "lot"
little did I know and was not told it was only 7.8:1 Compression Ratio 348 when I got it back !
And of course I had a cam put in it !   Yeee Hah!  (not)...

Being less than "rich" and once I figured out what had been "done", I tried to figure
how or what to do to "recover" and figured out I could swap in a 304/360 Crank.
Had a shop do what I couldn't, re-balanced rotating parts, and I re-assembled.
Everything the same except the crank, same +.030 Badger Slugs, cam, yada.
That made it 365 C.I. and 9.07:1 Static CR and obviously ran much better.
But I was still "unhappy" with the CR because of the Cam I had selected and was still using.

So some years later I got a cheap pair of 1970 304 Heads and spent "big money" on them,
all new 360/401 size StnStl 11/32 Stem Pro-Flow Valves, mild porting / bowl blend, yada,
and had them milled as much as they could be milled for the smallest possible chamber
which "used them up"  BUT being stubborn I wanted the 10.2 or more CR to work with
that 1st Cam I had chosen, was still in the motor, and had never realized it's potential...
So I swapped on the big-bucks '70 rubbed-on Heads on the 365 and got 9.68:1 Static CR.
Better again, but still was not satisfied, but it would wind-up for sure...

One evening at Test & Tune with no slicks just the street radials and having fun...
Self Control "lapsed", wound it to 6k+ in 1st & 2nd, and come to find out spun #5 Rod Brg
but did not know for sure until later...  denial... kept driving it, maybe 300-400 miles
until the Rod Cap offset ground the Crank enough for the Badger Slug to smack the head ! Doh!
So 1 more time tear it down, get another 304/360 Crank, but this time "a little more"...
Bought the Zollner Cast 360 Pistons cheap, eBay iirc, and bought 2 Sets, a +.030 Set & a +.040 Set.
Got dims off the Zollner Slugs, had new Crank Offset Ground +.010 to make it 3.46" Stroke.
Re-assembled it my self, iirc the cast Zollner Slugs were .005 proud of the Block Deck.
That build was now 367 C.I., a "legit" 6.0 Liters, and 10.17:1 Static CR, FINALLY, and it ran really good...
Then it wiped off a lobe on that same 1 Cam I'd been "chasing" for who knows how long!
Dang!

So another tear down, block clean, yada... got a new Lunati Cam with specs I liked...
Nope, couldn't use it... all that other stuff I'd done backed me into a corner...
New Cam had more overlap and I had "no" Piston to Valve Clearance with my custom rotating Assy.
That old 1st Cam I'd been "chasing" was a Stock AMC Cam re-ground by Chet Herbert in the 80's
and had the same somewhat low overlap with reduced base circle, more lift, and more duration.
So I "back pedaled" went looking for an old-school-cam-tech Cam, found an Elgin Pro-Stock Cam,
it worked, and worked pretty good, but it runs out of umpf at about 5500 or so.
That's what is still in the car now.

I would do so many things completely differently now, but I was stubborn ( dumb ).
But all this just typed up right here is really a story about how I learned I guess, and slowly maybe...


Edited by PHAT69AMX - Feb/20/2019 at 12:21pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 1982AMCConcord Quote  Post ReplyReply Direct Link To This Post Posted: Mar/18/2019 at 6:28am
Originally posted by PHAT69AMX PHAT69AMX wrote:

I guess flywheel HP would be about that, depends what "HP Loss % Factor" is used.
311 HP Flywheel results from 10% loss and 280 RWHP
375 HP Flywheel results from 20% loss and 300 RWHP

The 277-282 HP Chassis Dyno printout was before the mild ported big $ '70 Heads
and still had Badger Slugs, stock-ish '70 Heads, 3.44 Stroke, 365 CI, and 9.07:1 CR.
imho the 727 uses quite a bit of HP, and the Cheap B&M Converter is in-efficient, so 10-20% loss?

343-348-365-367 Compression Ratio "History" = 10.2:1, 7.8:1, 9.07:1, 9.68:1, 10.17:1

In about 1988 when I paid a shop to do the 1st rebuild on the original ~95k mile
stock 1969 343 4V 10.2:1 from my AMX I bought July 1985, and knew less than a "lot"
little did I know and was not told it was only 7.8:1 Compression Ratio 348 when I got it back !
And of course I had a cam put in it !   Yeee Hah!  (not)...

Being less than "rich" and once I figured out what had been "done", I tried to figure
how or what to do to "recover" and figured out I could swap in a 304/360 Crank.
Had a shop do what I couldn't, re-balanced rotating parts, and I re-assembled.
Everything the same except the crank, same +.030 Badger Slugs, cam, yada.
That made it 365 C.I. and 9.07:1 Static CR and obviously ran much better.
But I was still "unhappy" with the CR because of the Cam I had selected and was still using.

So some years later I got a cheap pair of 1970 304 Heads and spent "big money" on them,
all new 360/401 size StnStl 11/32 Stem Pro-Flow Valves, mild porting / bowl blend, yada,
and had them milled as much as they could be milled for the smallest possible chamber
which "used them up"  BUT being stubborn I wanted the 10.2 or more CR to work with
that 1st Cam I had chosen, was still in the motor, and had never realized it's potential...
So I swapped on the big-bucks '70 rubbed-on Heads on the 365 and got 9.68:1 Static CR.
Better again, but still was not satisfied, but it would wind-up for sure...

One evening at Test & Tune with no slicks just the street radials and having fun...
Self Control "lapsed", wound it to 6k+ in 1st & 2nd, and come to find out spun #5 Rod Brg
but did not know for sure until later...  denial... kept driving it, maybe 300-400 miles
until the Rod Cap offset ground the Crank enough for the Badger Slug to smack the head ! Doh!
So 1 more time tear it down, get another 304/360 Crank, but this time "a little more"...
Bought the Zollner Cast 360 Pistons cheap, eBay iirc, and bought 2 Sets, a +.030 Set & a +.040 Set.
Got dims off the Zollner Slugs, had new Crank Offset Ground +.010 to make it 3.46" Stroke.
Re-assembled it my self, iirc the cast Zollner Slugs were .005 proud of the Block Deck.
That build was now 367 C.I., a "legit" 6.0 Liters, and 10.17:1 Static CR, FINALLY, and it ran really good...
Then it wiped off a lobe on that same 1 Cam I'd been "chasing" for who knows how long!
Dang!

So another tear down, block clean, yada... got a new Lunati Cam with specs I liked...
Nope, couldn't use it... all that other stuff I'd done backed me into a corner...
New Cam had more overlap and I had "no" Piston to Valve Clearance with my custom rotating Assy.
That old 1st Cam I'd been "chasing" was a Stock AMC Cam re-ground by Chet Herbert in the 80's
and had the same somewhat low overlap with reduced base circle, more lift, and more duration.
So I "back pedaled" went looking for an old-school-cam-tech Cam, found an Elgin Pro-Stock Cam,
it worked, and worked pretty good, but it runs out of umpf at about 5500 or so.
That's what is still in the car now.

I would do so many things completely differently now, but I was stubborn ( dumb ).
But all this just typed up right here is really a story about how I learned I guess, and slowly maybe...

PHAT.... I read about the current set up a lot but I didn't know that you had gone through all that to reach the end engine combo. You put in a lot of work to finally dial it in. I have also been looking at the Lunati cams a lot.. every time I ask someone that is one of the cam companies that gets often mentioned. 

I liked the 701 and the 703... but I think the 703 might be a little too much. Its tempting... my friend used the 703 in a 360 build and made 430hp/430ft-lbs with Wiseco pistons and 291 heads. In another build he used the 701 cam with cast pistons and the 291 heads for get 325hp/375ft-lbs.... and that's not too shabby either. These numbers are flywheel and done on an actual engine dyno.   
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 1982AMCConcord Quote  Post ReplyReply Direct Link To This Post Posted: Mar/18/2019 at 6:33am
Hey guys.. sorry I didn't come back sooner.. I don't have good access to forums on my cell phone and its difficult for me to come back to a computer to type a good message. Then by the time I do make it back to the computer... I forget about all the threads I have been participating in! 

Anyway.... you guys are right... the best bet would be to just use the forged Wiseco pistons... they are worth the money because they are a quality pistons that will make a big difference in performance and long term peace of mind. Thanks a lot for all the input.  

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