Thank you for clearing that up for me!
Finally, my first 360 and goals for it! I'll be asking a lot of questions.
- Thread starter trebor75
- Start date
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yellow rose
Overnight Sensation
^^^^^^^^^This^^^^^^^^^
The minimum clearance is designed into the piston, so the stated piston size is nominal, as "in name only".
On most forged Pistons today, for a nominal size of 4.030 the piston will probably measure 4.026-4.027 so finishing your bore at 4.0300 will give you .003-.004 clearance.
Also, in terms of percentages, if your piston is designed for .002 clearance, and you give it .003, you've just given yourself a 50% increase in piston to wall clearance. If you give it .004, that's a 100% increase.
Think in terms of percentages. That's why honing to four places after the decimal is important. And extra .0005-.0008 can be a pretty sizable increase in clearance, as a percentage of what the piston was designed to run.
Filled blocks, real race blocks and power adders will need more clearance.
Learning is fun. Just try not to make it expensive.
stixx
Well-Known Member
Slowing coming apart... slowly going back together again! 
YesSlowing coming apart... slowly going back together again!
I will try and get some more work done tomorrow.Spent a good amount of time today calibrating the bore gauge and then measure and measure again and finally a triple check. I felt like I got a good hang of using the tools. I did not use a stress plate. I measured each bore in 6 positions (took forever). The biggest number on taper was .0023 and out of round the same, .0023. These occurred one time each. I don't have the patience to write down all the measurements. But the bores look good enough for me. I'm gonna dingle berry hone them myself and get Speed Pro pistons. Have a good evening folks!
So now I'm waiting for some tools and parts to arrive. The engine will go together something like this:
Stock crank, rods & bore (honed by me)
All new bearings & oil pump
Ported (by me) 3769974 heads - Mr. Gasket 1121G
Speed Pro H116CP pistons
Xe268H and matching springs, new lifters, chain and gears, stock rocker assembly
LD 340 Intake
Street Demon 625 carb
Long tube headers
10" 3000 stall converter
3.55 or 3.73
I wonder what kind of HP I can expect, any rough idea?
Stock crank, rods & bore (honed by me)
All new bearings & oil pump
Ported (by me) 3769974 heads - Mr. Gasket 1121G
Speed Pro H116CP pistons
Xe268H and matching springs, new lifters, chain and gears, stock rocker assembly
LD 340 Intake
Street Demon 625 carb
Long tube headers
10" 3000 stall converter
3.55 or 3.73
I wonder what kind of HP I can expect, any rough idea?
like the pieces. me personally, I'd like a little more cfm's on top. Might short yourself a little in the upper power band
Could be 380 - 400 , with the bowl work, you have done... The compression bump,will make the torque curve : easier to tune, and be more stable to tune...
It's an expensive, learning curve.
It's an expensive, learning curve.
Change of plans! I ordered a set of Edelbrock RPM heads A lot of other things has started to come in recently too. Still waiting for the heads though.
I followed RustyRatRod's cam bearing install thread. Thanks Rusty! Everything lined up nicely, but of course I f...d up on the last bearing. Will have to get a new one and try again. Slid my old cam in the 4 ones I managed to install and it turned around no problem with my hands and a little assembly lube.
I'm gonna continue this buil in my old project thread: 1970 Duster project in Sweden
Hope you follow it there!
A lot of other things has started to come in recently too. Still waiting for the heads though. I followed RustyRatRod's cam bearing install thread. Thanks Rusty! Everything lined up nicely, but of course I f...d up on the last bearing. Will have to get a new one and try again. Slid my old cam in the 4 ones I managed to install and it turned around no problem with my hands and a little assembly lube.
I'm gonna continue this buil in my old project thread: 1970 Duster project in Sweden
Hope you follow it there!
Hey Dude, checked back in on this thread & wanted to comment....... in the 1st pics of the block, #6(bore#1 & crankpin) there is an area in the bore that appears to haveChange of plans! I ordered a set of Edelbrock RPM heads
I followed RustyRatRod's cam bearing install thread. Thanks Rusty! Everything lined up nicely, but of course I f...d up on the last bearing. Will have to get a new one and try again. Slid my old cam in the 4 ones I managed to install and it turned around no problem with my hands and a little assembly lube.
View attachment 1715090058
I'm gonna continue this buil in my old project thread: 1970 Duster project in Sweden
Hope you follow it there!
a circumferential crack or corrosion line, left in the pic...frt. of eng. side of the cyl bore. Optical illusion? Also, what is the new compression ratio target w/the Eddy heads?
There is going to be a difference in intake port from the matched teener ports, but should be fine.
Hi. Could you save and then post up the picture where you see it? Maybe even draw a circle or an arrow? I can't find it in the photos. If I have all the numbers right for the compression calculator, with the heads, speedpro pistons and thin mr gasket It will be 10.29
Post#152, actually the 5th image, 1st one of the bore.....about 1/3 down from the deck to the left in the image as oriented..........I'm too computer challenged to do it
faster the other way,lol!
I see it now too. The picture after is on the same side of the bore but taken with a flash.
I have gone over this block and have not seen or felt anything out of order. But hey, I cant swear I did not miss this. I hope it's not a crack I have missed! I will take a real close look at that. Thanks for spotting it, lets hope it's all good!
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