High Compression 2.6L Astron.

[Superscan811]

Some freshly machined blocks...


The block at the back is for the turbo build.



The knife edged crank, back from being balanced.



Comparison of a standard crank (top) v knife edged crank (bottom]


From these pics you can see how uneven the webbing is, between the outside of the bigend and the main.
With the next crank, I'll even it up a bit more.


Pistons and ARP bolts.

Was surprised the 4g54 turbo pistons (middle box, 393 grams) actually weigh less than the N/A 22R pistons (top box, 460grams. Bottom box 449grams). May have a go at reducing some of their weight before they go in.


Also bought an 2-ton engine crane and engine stand because it was getting to be a bit of a pain having to borrow them..

Starting the build process shortly.

Cheers.

[A112H]

Looks the goods mate. I am looking forward to seeing this come together, before you start mine that is

[Superscan811]

Starting to space out the 40mm motorbike carbs and it is a P.I.T.A. (pain in the ass).

10 hours work and I'm around 80% done..









Definitely easier to just make the manifold to suit the current carby spacing.



Another bit of kit arrived this week, a complete EDIS setup (Electronic Distributor-less Ignition System).

It also comes with an aluminium pulley..

This will allow me to use electronically controlled timing with the carbies.





Still need to finish "shaping" the Turbo diesel crank..


Cheers.

[dvsfin]

Another bit of kit arrived this week, a complete EDIS setup (Electronic Distributor-less Ignition System).

It also comes with an aluminium pulley..

This will allow me to use electronically controlled timing with the carbies.

the motec in my galant just uses the ref/sync from a magna dizzy, are there any advantages to running a trigger wheel setup?

[Superscan811]

the motec in my galant just uses the ref/sync from a magna dizzy, are there any advantages to running a trigger wheel setup?

Yes, you get the correct timing.

With the cam timing, there are a lot of variables..
Timing chain/belt and gear wear.
Chain/belt tension.
Dizzy gear wear and backlash.

While this probably would make bugger all difference in a standard engine, if you are trying to get every last horse out of an engine, it's worth it.

One of the main reasons I went for an EDIS setup is because I want to run CDI wasted spark system. I was able to convert one of the older standard dizzy to run it but changing the timing curve was getting annoying.

I'll be using a MegaJolt to control/change the timing now.

Cheers.

[amehel0]

Why did you go for that instead of a magna dizzy? you still have both a signal for each cylinders TDC as well as a home signal and its hall effect. or even just a bosch unit thats got the hall effect but no dizzy cap? Also is the knifing just for minimising the weight and to help balance the crank? Great build btw

I hate to break it to whoever thinks that astron 4g54 blocks are weak but thats not true. If you treat a Alloy Cast Iron block like its a football then it will crack, however if you take due care such as having clean threads, torquing off bolts replacing gaskets , cleaning mating surfaces and having freash oil and ample coolant you will not have such issues. Cast Iron is very easy to crack if you dont respect its britallity (word?). They came out with drop forged rods and crank and have a rock solid bottom end. However they dont like detonation. I flog the crap out of my triton frequently accelerating to 6500rpm and have never had issues with it. but i also change the oil and foil filter every 5000k use rust inhibiting coolant as apposed to regular coolant which although better then water will still make your block rust. And thats why im turboing mine. Honestly a 4g63 conversion would of been cheaper and easier but this engine has an awsome torque curve till you hit about 6500.

[Superscan811]

Why did you go for that instead of a magna dizzy? you still have both a signal for each cylinders TDC as well as a home signal and its hall effect. or even just a bosch unit thats got the hall effect but no dizzy cap?

Again, it comes down to accuracy. When setting your timing, look how much the timing mark moves around. Quite often, it will move around a few degrees and you just "average" the center.

With a high compression engine, this will cost you several kw's because you can't average your timing, you must set it for the worst case, otherwise you'll get a lot of detonation.

Also is the knifing just for minimizing the weight and to help balance the crank? Great build btw

Thanks..
"True" knife-edging is done to reduce turbulence caused by the leading and trailing edges of the crank counterbalances. Doing this, of course, will also reduce the mass of the crank.
You round the leading edge and chamfer the trailing edge (a bit like a plane wing), this helps the crank "cut" through the air.

Chamfering the bottom edge was done to reduce the weight.

I also tried to make the crank shape roughly symmetrical.

Cheers.

[amehel0]

Fair enough i had a look on the net about knifing and people were saying cutting through the oil in the sump but the 4g54's crank should never be cutting through the oil in the sump as it has an oil screen to stop that. Fair enough with the timing on a high comp engine, but is that variation in the timing due to the distributor and 'spark method' (ie single coil and distributor vs Coil on plug or wasted spark etc) or the hall effect sensors? What i mean is in effect is the gear/tooth system more accurate.

[Superscan811]

people were saying cutting through the oil in the sump

You NEVER want your crank to hit the oil reservoir in the sump, that would cause a LOT of major problems.

but is that variation in the timing due to the distributor and 'spark method' (ie single coil and distributor vs Coil on plug or wasted spark etc) or the hall effect sensors?

It's because there are SEVERAL components between the crank and the dizzy output that wear, streach, contract and have backlash etc...

What i mean is in effect is the gear/tooth system more accurate.

yes it is..

Cheers.

[cheaterparts]

Fair enough i had a look on the net about knifing and people were saying cutting through the oil in the sump but the 4g54's crank should never be cutting through the oil in the sump as it has an oil screen to stop that. Fair enough with the timing on a high comp engine, but is that variation in the timing due to the distributor and 'spark method' (ie single coil and distributor vs Coil on plug or wasted spark etc) or the hall effect sensors? What i mean is in effect is the gear/tooth system more accurate.

have you ever thought how the oil gets back to the sump from the head or the top balance shaft housing
it drops on the crank through the a hole at the rear of the head then through a matching hole in the top of the block then just drops on the crank
the balance shaft houseing has 2 holes that drop straight on top of the crank

now the crank is spinning a quite a rate so creats a low presure area ( speed up air and that makes a low preasure )
so this oil clings to and around the crank area untill the weight on the oil over comes the low presure
now we have a crank crashing into oil mist and droplets - that makes drag and heats up oil at the same time

by the way the faster the crank spins the worse this becomes

there is no complete cure ! unless we dont run any oil ,also not a good plan

so by making the crank that cuts through the air better does 2 things first it cuts though this thicker oil misty air
and it cuts though the air and this less drag also doesn't speed the air as much ,so in turn the low presure is not as great

to add to a knife edge crank a good close fitting crank scraper is also worth fitting

by cutting the drag means more of the power can be used to drive the car and that is quite a few HP

-by the way getting some weight out of the spinning mass never hurts on the 4g54 ether the whole bottom end is dam heavy

[Superscan811]

Decided to remove a bit more weight from my knife edged 2.6L crank.

Still a fair bit more work to be done but getting there.

STANDARD CRANK



MK-1



MK-2 (Work in progress)

Had to cut a V-Block into 3 pieces to better support the crank. I also used old bearing shells so I didn't damage the crank.




Work done so far..
1. Reduced the diameter of the counterweights so they are the same diameter as the bigend.
2. All the counterweights are now the same thickness.
3. Machined the edges (last pic) to make the shape more uniform.


Still need to chamfer/round the leading and trailing edges then side drill the bigends (to remove some more weight).

After that, I'll statically balance it before sending it away for a dynamic balance.

Cheers.

[amgis_obrut]

cranks are nice

here's something to ponder over
mmmmmmmm gun drilled

[Superscan811]

cranks are nice

here's something to ponder over
mmmmmmmm gun drilled

Would like to take the crank that far but my skill and machinery are somewhat lacking at the moment.

This is what I'm wanting to do (jump to the 45-second mark)

The side drilling of the big ends along with machining the webbing between the big-ends and the mains should help compensate for the weight removal off the counterweights.

Also, the piston and rods will be significantly lighter than standard, fingers crossed, the end result should work quite well.

BTW: I know removing weight off the outside edge of the flywheel will make a far greater difference than what I'm doing to the crank, I just wanted this build to be a bit different.

Cheers.

[Superscan811]

Knife edging done.


Drilled and reamed all the oil galleries, from 6.5mm to 7.25mm which will allow for 25% better oil flow.

Spun it up to 2500 in the lathe and there seems to be only a small imbalance.

Getting hold of a 25mm dia rod of tungsten carbide to use as Mallory Metal for the counterweights (approx 3X the weight of steel).

This will allow me to increase the the mass of the counterweights, which will dramatically reduce the bearing peak loads, but still allow the engine to spin up fast.


To Do:

1. Side drill the big-ends.
2. Polish.
3. Shot peen.
4. Grind 6-tho under size.
5. Nickel plate (3-tho) then hydrogen de-gas.
6. Install Tungsten counterweights.
7. Balance.

Should be interesting...


Cheers.

[geezer101]

How's the quad carby set up Ver2.0 going on this build? The crank is coming up a treat btw!

[Superscan811]

How's the quad carby set up Ver2.0 going on this build?

Just deciding whether to use the CV's or these Flat Slide carbies.

The CV's need to be mounted at 45-degrees but the Flat Slides are mounted as shown.



The beauty of these is the air path is straight and un-obstructed.

The crank is coming up a treat btw!

Thanks. Decided to put the time, effort and money into doing it right.




Cheers.

[cheaterparts]

look like very short runners there sunshine have you done the sums on what lenth you should be using ?

and I think you should be using electic water pistols my self

[Superscan811]

look like very short runners there sunshine have you done the sums on what lenth you should be using ?

To be honest, no..

BUT in my defence, I'll be using an airbox with a cold air induction system that will force the air in via a front air dam. True power won't show up on a dyno but who care.
A dyno isn't where you have the most fun..

As for the water pistols, it's in the works, just wanted to be a bit retro ATM..

Cheers.

[4B11LA]

HI
my webers were sucking hot air in the lancer with broken filters and one trumpet shorter than the rest to clear the tower.....
just get it together and refine the ugliness later on as you go or it will never get finished !! lol
btw i gave up on my old log in and made a new one...

[amehel0]

Hey man its looking good. I recently got my mill and im slowly learning the process and getting all the parts i need to machine things. So the crank is from a 4d56 and will fit in a 4g54 without any mods? or do you need different bearings or flyeheel? just in the process of pulling a crank out of a 4d56.

[Superscan811]

Sorry for the delay in replying amehel0,
The 4D56 crank will need the mains machined down from 66mm to the 4g54 standard 60mm.

The best way to do this would be to turn them down in a lathe to 61mm, then have them ground.

Cheers.

[amehel0]

oh yeh. do you think that the diesel crank(4D56) is stronger then the 4g54 one even though the 4g54 one is drop forged? im only using the diesel crank cause it's free! also are you just using the standard diesel conrods or aftermarket? man hope to see the high comp engine running soon!

[Superscan811]

oh yeh. do you think that the diesel crank(4D56) is stronger then the 4g54 one even though the 4g54 one is drop forged?

The 4D56 crank is also forged and while the machining 6mm off the mains would negate some of those benefits, it will be shot peened before use, this will help.
Also, the bigends are closer to the mains and in theory, this should allow it to handle a more torque with less deflection.

... also are you just using the standard diesel conrods or aftermarket?

I wouldn't use the diesel rods, they will most likely be too heavy for a N/A build.
Standard 4G54 rods (properly prepped) will handle almost anything a N/A build will throw at it.

That said, I'm going with a set of forged H beams, mainly for the weight reduction.

Because of the dramatically reduced counterweights on my crank, it will need light rods and pistons to help offset what has been removed (my crank started at 18.7kg but now weighs 14.7kg).
The Forged rods are around 25% lighter than the factory rods, and the forged pistons, 20% lighter than standard, that alone should allow the engine rev quickly and reduce the peak loads on the bearings at low rpm's

man hope to see the high comp engine running soon!

As this is going to be in a daily driven vehicle (along with a few motorkhanas, khanacross, etc...) , I want it to last a while so I'll spend a little more time getting everything 100% (or correctly interpreted as lazy and usually unmotivated).

Cheers.

[Superscan811]

Decided to tidy up my lightened flywheel a little.
It's now down to 7kgs and I still want to do a bit more to lighten the outside.

Original lightened flywheel




Currently.




The majority of the weight was removed by the 45deg cut behind the ring-gear, the rest of the surface was machined approx 1mm to clean and even it all up.


Cheers.

[A112H]

[damian]

nice work as always

[amehel0]

Nice did you do that on a lathe or a mill?

[Superscan811]

nice work as always

Thanks guys.

Nice did you do that on a lathe or a mill?

I turned it in a lathe.
Could possibly remove a bit more from the front surface if I want to go any lighter, but I'd prefer to make a steel one as I think I've just about reached the safe limits of the standard flywheel.


Cheers

[Superscan811]

Well I picked up my Titanium valved head today (it's only been sitting at the engine conditioners for the last 6 months or so).
Using 2mm oversize valves with 7mm stems, bronze valve guides and Beehive valve springs.
Inlets are 48mm and the exhaust is 39mm
It has 2mm larger valve seats as well as Beryllium-Copper exhaust valve seats to help remove the heat from the valves, but the inlet seats are steel because the inlet valves are mainly cooled by the fuel-air mix.

The head at the top of the picture has 1mm oversize Stainless valves(for my Turbo build).


Cleaned up the ports and chamber a bit as well.




The weight difference between the valves is HUGE..

Standard steel Inlet valve and spring retainer (couldn't find any collets).





Titanium Inlet valve with collet and spring retainer.


Almost 1/2 the weight.

Have tested the head with a lumpy cam, designed for 12.5:1 CR, and all the valves miss each other.

Have to CC the chambers yet and need to dummy assemble the engine to see how much the pistons need to be flycut.

Should flow well I think.



Cheers.

[A112H]