86mm Turbo Pistons For NA Motor

[Competition CNC]

Wow.  I dont even know where to begin......

Its over whelming.....

Look at it this way Jim,  as a Professional Engine builder, it can only increase your workload.

Yea but I hate to see people go thru the aches and pains of learning.   But some people like working on stuff as half the fun of it all.

When I was 12 (1976) I rebuilt my 1972 honda z50a motor and it was all new to me.  I had a basic understanding of engines from working on my 5hp briggs and stratton engine from my go kart.  I had blown that Briggs up several times and had to replace the piston and rod from donor engines, but that honda engine was some kind of complicated exotic engine for me at that time.
After I took the engine apart and looked at all the pieces, I bought a manual to put it back together.
So I learned at an early age that getting in deep over your head can be scary but with enough info you can dig your way out.

When I was 8 or 9 my dad who was a radial aircraft engine mechanic (late 1940's early 50's) in the air force, let me struggle and work my way threw it to learn how to solve problems.  Each night after I went to sleep he would check out my "progress" in the shop on my briggs 5hp engine.  When I progressed to the honda engine a few years later, he recommended a service manual.  A what, I said.  I learned to really like service manuals.   I rebuilt my first 350 chevy engine at 15 for a T bucket I was building.  That was my first car at age 16 and I learned a lot in the process and it was frustrating at times.
So I'm very familiar with working your way threw the unknowns in with an over whelming project.

I guess some people enjoy the challenge as much as the results.

[BATTMAN]

Every man has to know his own limits.  Box the motor up and send it to a builder.

[knecum]

Every man has to know his own limits.  Box the motor up and send it to a builder.

Ill give you a good deal!

[fvance]

My first Busa motor I built myself, all oem parts with Carpenter head. Second motor not many oem parts with Carpenter head. I thought it was beyond my expertise or lack of. Knecum built it and is bad azz.

[GRUNTMAX]

Not possible, many bent valves. Will now have to purchase the pistons I should have used in the 1st place

[fvance]

If you bent all the valves get a set of Gen2 titaniums. They drop right in. You can find a set cheap, nitrous and turbo guys cant run them.

[80 Theory]

The price of having a professional build your motor is nothing compared to the price of the parts.  Steve Knecum put together a Bonneville RECORD SETTING, 1634 stroker motor, in record time for me.  271 horsepower on 110 ERC race gas, 284 Horsepower on VP-Q16.

Yeah, I might have been able to do it.  I know about rod bolt stretch, piston clearance, bearing clearance, etc.  I've built stoked Harley engines for years (truing the flywheels in my lathe).  I even have my own remote Sunnen hone.  But I wanted it done right the first time!

Life is short.  I'm spending mine riding.

Mike

[GRUNTMAX]

  Only 4 bent exhaust valves. No other damage. Maybe it was the compressed spring steel head gasket that stuffed the numbers up, & when the head was taken off the deck height clearance was around 0.4mm less than it should have been.
I'll save the other motor for my supercharged stroker motor build. Who knows, I may have a professional builder do that for me.

[GRUNTMAX]

Wow.  I dont even know where to begin......

Its over whelming.....

Look at it this way Jim,  as a Professional Engine builder, it can only increase your workload.

Yea but I hate to see people go thru the aches and pains of learning.   But some people like working on stuff as half the fun of it all.

When I was 12 (1976) I rebuilt my 1972 honda z50a motor and it was all new to me.  I had a basic understanding of engines from working on my 5hp briggs and stratton engine from my go kart.  I had blown that Briggs up several times and had to replace the piston and rod from donor engines, but that honda engine was some kind of complicated exotic engine for me at that time.
After I took the engine apart and looked at all the pieces, I bought a manual to put it back together.
So I learned at an early age that getting in deep over your head can be scary but with enough info you can dig your way out.

When I was 8 or 9 my dad who was a radial aircraft engine mechanic (late 1940's early 50's) in the air force, let me struggle and work my way threw it to learn how to solve problems.  Each night after I went to sleep he would check out my "progress" in the shop on my briggs 5hp engine.  When I progressed to the honda engine a few years later, he recommended a service manual.  A what, I said.  I learned to really like service manuals.   I rebuilt my first 350 chevy engine at 15 for a T bucket I was building.  That was my first car at age 16 and I learned a lot in the process and it was frustrating at times.
So I'm very familiar with working your way threw the unknowns in with an over whelming project.

I guess some people enjoy the challenge as much as the results.

I was a Fitter & Machinist, Marine Engineer, Fishing Master (Perfect Storm job) & Saturation Diver (flangemaster "No Leaks"). I was learning how to use MastercamX & Solidworks while I was at sea working before I got wiped out by the drunk driver & copped this brain injury, now I can't even get past the first lesson.  Challenge ? More like a frustrating rehabilitation.
So how would you CNC port a head for a Supercharged motor ? Oversize Exhaust Valves only ?

[80 Theory]

I'd CNC my head by putting it a box and sending it to Bob Carpenter.

Mike

[Oz Booster]

Brad was it running fine without noise for a while?? sort of surprised it made 20 kms if you had a clearance prob

My take on a supercharged motor is its essentially a very big all motor and should be treated as such in just about everything except compression and even that i think not as low as a turbo ,
 unlike a turbo that has backpressures and needs exhaust velocity and  have the huge mid range torque rise

[GRUNTMAX]

Brad was it running fine without noise for a while?? sort of surprised it made 20 kms if you had a clearance prob

My take on a supercharged motor is its essentially a very big all motor and should be treated as such in just about everything except compression and even that i think not as low as a turbo ,
 unlike a turbo that has backpressures and needs exhaust velocity and  have the huge mid range torque rise

It was running fine without noise. Was shifting up from 2nd to 3rd whilst going down a slight slope.
When I let the clutch out (without using easyshifter) back wheel just locked up. My CR is already low enough so I'll use Muzzys 13:1 Pistons (waiting on price).

Supercharging;

Have a Gen1 Intake with Brocks Offset Cam Pin & Gen2 Intake with the Roller Cam Chain Sprockets sitting in a box ready to use for the Supercharged motor. All to do with the lift & duration. But I reckon on a 1500cc + busa motor if I had Competition CNC do a CNC job on a Gen2 Head it would be good with 1mm oversize exhaust valves only.
Maybe Jim can do the figures ???? What do ya reckon ???

1500cc + Supercharged Busa Cams
Intake Opens BTDC : 28 degrees
Intake Closes ABDC : 68 degrees
Exhaust Opens BBDC: 72.5 degrees
Exhaust Closes ATDC: 28.5 degrees
Cam Calculations  Lobe Center / Duration for 110 & 112 degrees
Overlap: 56.50 degrees
Intake Duration: 276.00 degrees
Exhaust Duration: 281.00 degrees
Intake Installed Centerline of 110.00 degrees ATDC.
Exhaust Installed Centerline of 112.00 degrees BTDC.

[Oz Booster]

What cam chain  tensioner,
and Roller without top guide ?? or cut down guide and spacers ?

[GRUNTMAX]

What cam chain  tensioner,
and Roller without top guide ?? or cut down guide and spacers ?

APE Manual Cam Chain Tensioner
Roller without top guide.

Never mind, I remember when I was a machinist using a Bridgeport Vertical milling machine & "touching on". Well, I reckon after 20kms one day & 10kms the next before those 4 bent exhaust valves "touched on" is about the best "touch on" ya can get.

About the best compression ratio I could get with those pistons & cams would be 9.05:1
Head Chamber Volume  : 18.00 cc
Vlve Reliefs Piston  :  8.27
Deck Clearance @ TDC :  3.20
Deck Volume @ TDC    : 26.86
Head Gasket Bore     : 86.45
Head Gasket Thickness:  0.72
Head Gasket Volume   :  4.23
Swept Cylinder Volume:395.00
Total Combustion Vol : 49.09cc
Compression Ratio    :  9.05:1

Base Gaskets
 3.1mm
 2.4mm
 0.4mm
=5.9mm
-3.7mm removed
=2.2mm exhaust valve clearance
+1.0mm deck height clearance with previous 3.7mm base gaskets
=3.2mm deck height clearance

Looks like the 13:1 pistons are a must have

...and even then, the CR will come up a bit more if required as those pistons are rated @ 13:1 for Gen1 18.8cc head instead of 18cc Gen2 head that I'm using.

[knecum]

Why don't you just have someone build it and then have fun.. Your doing way to much math and then have shit contact..

[GRUNTMAX]

Why don't you just have someone build it and then have fun.. Your doing way to much math and then have shit contact..

This is my rehabilitation. I have a calculator, & Dynomation5 software for the CR calcs.
While I'm waiting on parts, plenty of time to get ready for the next step. My latest stuff up was bunging the cases back together then finding out my gear selectors weren't right then I had to split em again
Today, it started, with the 13:1,s in it. Just hope it doesn't blow up on the dyno