Pros/Cons removing balance shafts

[Rally_2.6LC]

Exactally what it says guys, just wanting to know the good and bad points of removing the balance shafts from a 4G54 TR magna (going into my LC).


Cheers Matt

[Jamie]

Removing the balance shafts, as long as you don't mind the engine rocking around a little more, is definitely rewarding.

The engine becomes a lot more responsive, while I have heard people suggest that you gain 10HP, I doubt that you really gain much horse power, but rather an increase in torque.

My L200 ute has a block from a GK sigma, Head from a TR Magna, High Compression Pistons and injection from a TP.
So effectively my engine is almost a TR just without the knock sensor and it is a wide bell housing type.

The balance eliminator kit includes a metal ring to knock into place where the top balance shaft bearing goes to block the oil gallery.
But nothing is supplied to block the rear galleries of the balance shafts.
When I built my engine, the local machine shop pushed in the rear bearings in around the wrong way to block the oil galleries.

Oil Pumps.....
This is a big one.
TR Magna engines are known for having a higher flow pump than the sigmas.
While that is good, you will destroy a genuine Magna pump just a quick as a Sigma Pump as the pump is no longer being held true with the 30cms of balance shaft aligning it now missing.
As both pumps have an alloy casing and steel gears, they start to shred the internals of the pump and start to score the internals of the pump on the intake side.
A better solution is to buy a Mellings after market pump which has a cast iron casing.

Replacement chain:
A problem with removing the balance shafts is how do you tension the oil chain.
With balance shafts in place, the chain is tensioned on the exhaust side.
You can no longer tension the chain on sigma block as the tension doesn't meet with the replacement shorter chain.
TR and TS Magnas do how ever have an automatic chain tensioner that tensions the chain in between crankshaft and the oil pump.

I did consider this when I built my engine, but it was a two week wait and $100 for a genuine one or $150 for a non genuine one from Repco.

I ended up just using a new guide and a pre stretched chain of about 10,000Km.
I adjusted the lower guide to hold tension on the chain and I have hoped for the best.
But doing this when running in the engine created a weird ticking noise much like spinning a ratchet spanner when I de-accelerated. It was just the chain wearing the toe off the guide.
That is really not the sound you wish to hear when running in a new engine.

So I would highly recommend using a TR Magna Chain tensioner.


Sorry, this really hasn't given you a defined Pros / Cons for your question, I just thought it might be better If I give you my experience and thoughts with the custom engine that I built.


Jamie

[Rally_2.6LC]

Well that does help, as I just bought a TR engine to build up.
I was considering buying one of the balance shaft removal kits from eBay.
I wouldnt have guessed that with the oil pump destroying itself.....what is the after market one you got? is it still a high flow one?

Ill be running TR block, 2L Sigma Jap head (#3 cam and double valve springs, just re-conditioned), forged flat top pistons and the standard intake and exhaust.


Cheers Matt

[Skidmark]

here ya go mate

http://www.sigma-galant.com/viewtopic.php?f=30&t=2077
Skidmark

[81GL]

Ill be running TR block, 2L Sigma Jap head

Just curious... but why are you wanting to use little valves and small ports on a 2.6.... ?

Nick.

[Rally_2.6LC]

For the upped compression and the head has just been reconditioned with double valve springs and #3 cam - and i can use it without having to spend anymore money on it......i would love to use one of the magna heads, however i just dont have the money to do one up and get EFI converted to rear wheel drive at the moment.
Just looking to get back into racing and then ill fix it up down the track, plus if I go EFI that means ill change the category I race in and there are a lot of faster people/cars in that category.


Cheers Matt

[81GL]

Arh okay.

I was getting the jist that you were going out and starting from scratch. understandable if you already have it though.

Nick.

[Sigmaproject]

Quote ;;Oil Pumps.....
This is a big one.
TR Magna engines are known for having a higher flow pump than the sigmas.
While that is good, you will destroy a genuine Magna pump just a quick as a Sigma Pump as the pump is no longer being held true with the 30cms of balance shaft aligning it now missing.
As both pumps have an alloy casing and steel gears, they start to shred the internals of the pump and start to score the internals of the pump on the intake side.
A better solution is to buy a Mellings after market pump which has a cast iron casing. End quote.
---------------

I have read this before. I have had the balanced shafts removed and a TR pump in for nearly 10 years, with no problems.

Someone on the old site put up a pic that showed that there is no difference in chain alignment between the 2 pumps.

[turbosigma]

Balance shaft turned down on a lathe.

although this is 4g63.

http://i547.photobucket.com/albums/hh46 ... G_2820.jpg

http://i547.photobucket.com/albums/hh46 ... G_2818.jpg

[81GL]

Balance shaft turned down on a lathe.

although this is 4g63.

http://i547.photobucket.com/albums/hh46 ... G_2820.jpg

http://i547.photobucket.com/albums/hh46 ... G_2818.jpg

Nice idea.

Has anyone really had that much trouble with the oil pump due to this?

[Superscan811]

TR Magna engines are known for having a higher flow pump than the sigmas.
While that is good, you will destroy a genuine Magna pump just a quick as a Sigma Pump as the pump is no longer being held true with the 30cms of balance shaft aligning it now missing.

While this is true, think of the forces applied to TURN the balance shafts and where that force is directed.
The forces exerted on the bearing surfaces, due to trying to spin the balance shafts at TWICE the engine revs, would far exceed those of just turning the oil pump.
Remember, there is a film of oil that protects the metals from contacting.

As a case in point....
My brother originally had a GE sigma back in 1982. He rebuilt the engine, removed the balance shafts and drove it VERY hard. I bought the sigma off him in 1985 and again, drove it very hard.
I stripped the engine down in 1993 and there was no visible damage/excess wear in the oil pump and the oil pressure was always fine.
The reason I pulled th engine down was due to it blowing too much smoke for my liking, it turned out the valve stem seals were shot.

I was putting in around 40,000k per year (I had a girlfriend that lived 800k away and I drove there every 3rd weekend for over 18months).

If you are worried about the "possible" extra wear, you could always have a shaft made up with a large flange at the back of the pump.
That would negate any of the other unwanted forces generated by the removal of the full shafts.

Cheers.

[Billsy]

ive just pulled my engine down and the pump had started to score the housing.
it still had the balance shafts in aswell. so ive got another pump and no balance shaft.

[Rally_2.6LC]

I do like the idea of turning the balance shafts down on the lathe, but keeping the section at the end to rotate in its housing, keeping the shaft level.

There is just some part of me that says, if something was engineered to have a weight spinning on the end of it, and you remove that weight that yes it may spin more freely but it may also S*** it self because now there is no weight.

Are the balance shafts across the Magna range the same (ie TP and TR) because I have a spare set of TP balance shafts I might experiement with turning down.
How do you remove the balance shafts out of the back of the oil pump?


Cheers Matt

[cheaterparts]

Exactally what it says guys, just wanting to know the good and bad points of removing the balance shafts from a 4G54 TR magna (going into my LC).


Cheers Matt

good points - less fiction/weight for the engine to move ( results in more usable power/torque )
there are 3 less bearings to feed so a std pump works a bit like a H/V pump
by removing the balance shafts and the long std drive chain removes the weakest link in the engine

the bad points ? I have not found any in 10 years of racing astrons ( my findings only )

Oil Pumps.....
This is a big one.
TR Magna engines are known for having a higher flow pump than the sigmas.
While that is good, you will destroy a genuine Magna pump just a quick as a Sigma Pump as the pump is no longer being held true with the 30cms of balance shaft aligning it now missing.
As both pumps have an alloy casing and steel gears, they start to shred the internals of the pump and start to score the internals of the pump on the intake side.
A better solution is to buy a Mellings after market pump which has a cast iron casing.

Replacement chain:
A problem with removing the balance shafts is how do you tension the oil chain.

Jamie

have you worn out a pump by removing a balance shaft ? the reason I ask is that the pump used in my race engine has never given any problem from this mod
I also dont use a high volume pump just a preped std sigma pump

as for the chain why do you need a tentioner just use the std lower guide it works fine

[Rally_2.6LC]

Yea I have no problems with the chain, I was going to use the existing guide to tighten it up.

When you say "the pump was preped", define preped. Is it just a standard pump that has had the balance shaft removed or is it something different?


Cheers Matt

[cheaterparts]

When you say "the pump was preped", define preped. Is it just a standard pump that has had the balance shaft removed or is it something different?
Cheers Matt

I alway check clearances in the pump and tighten them if needed

also I open up the holes for the oil releave so that the oil presure does not go to high on cold start up

[DragonCypher]

So how is the lower balance shaft removed (the one that ISNT behind the oil pump)?

I got the one out of the oil pump simply by unbolting everything i saw and it slid out, the other one though is sealed in, with a welsh plug on the other end. Does the plug need to be removed?


Cheers,
Chris

[Rally_2.6LC]

I found that one came outu easily, all i did was unbolt it, tap it with a rubber mallet and turned it round a bit until the outside was half covering one of the bolt holes in the block, then stuck a screw driver in teh bolt hole adn behind the casing thing and levered it off.

I think im just going to go with turning down the balance shaft on a lathe and use balance shaft removal kit from ebay.


Cheers Matt

[Rally_2.6LC]

Ok I called a specialist in this field today and he gave me some great advice for 4G54 engines.

Its sorta to do with the balance shafts. If you are building an engine you dont intend on reving over 6000 RPM you should leave the balance shafts and standard oil pump in.
If you are planning on reving the engine higher than 6000 RPM (4G54's can get comfortably to 8500 RPM) then removing the balance shafts, getting the whole bottom end balanced are advisable but when reving this high YOU MUST GET A HIGH VOLUME OIL PUMP.
Apparently the 4G54's oil pump's are only good until 6000 RPM, because the pump is then spinning at 12000 RPM (twice the engine speed). This causes the pump to cavitate and thus the bottom end of the engine is starved of oil.

So Im getting a new high volume oil pump (about $800 for kit including chain). This pump only spins at half the RPM of the crank, so at 6000 RPM the pump is only doing 3000 and still providing more than enough oil to keep the engine happy.


Cheers Matt

[75wagon]

My mates dad used to work for RALLI-ART. They used to remove the balance shafts in the 2.6's they had in their Pajeros (these are the same Pajeros that used to win every rally they entered, or so I believe).
If you need any info maybe they would be good to contact?

[cheaterparts]

Ok I called a specialist in this field today and he gave me some great advice for 4G54 engines.

Its sorta to do with the balance shafts. If you are building an engine you dont intend on reving over 6000 RPM you should leave the balance shafts and standard oil pump in.
If you are planning on reving the engine higher than 6000 RPM (4G54's can get comfortably to 8500 RPM) then removing the balance shafts, getting the whole bottom end balanced are advisable but when reving this high YOU MUST GET A HIGH VOLUME OIL PUMP.
Apparently the 4G54's oil pump's are only good until 6000 RPM, because the pump is then spinning at 12000 RPM (twice the engine speed). This causes the pump to cavitate and thus the bottom end of the engine is starved of oil.

So Im getting a new high volume oil pump (about $800 for kit including chain). This pump only spins at half the RPM of the crank, so at 6000 RPM the pump is only doing 3000 and still providing more than enough oil to keep the engine happy.


Cheers Matt

who was the specialist ?

I run to 7200 rpm with a std preped sigma pump and so far no oiling problem
the same set was used for 4 years of hillclimb and sprints before a rebuild and the bearings
came out looking like new so the pumps are quite safe to these revs
I dont think a H/V pump is needed and have not used one myself

as for a special high vol pump why not just get a fork lift pump - scott the ebay junky has a pic on here somewhere of one

[Rally_2.6LC]

Specialist was Ron Masing of Coltspeed.
I may not buy a high volume oil pump just yet, going to get engine bored and balanced first along with a rev limiter (does anyone know any good brands).


Cheers Matt

[leoca]

I am unsure if this will help , but I recall that few years ago I removed the balance shaft from my 4G54 equipped LC. It was also carby turbo.
As I hadn't tuned it properly i think the engine was running lean (but great fuel economy compared to the other carby I had and the engine started overheating before long, i found out the head gasket had gone.
I then drove it around a bit too long like that.
Performance began to drop off, something wasnt right with her and one day upon starting i accidently stepped on the pedal to which it revved over 6000 rpm id say for sure.Soon after, same day or next, I realised that I had little or no oil pressure , it was running poorly on boost and funny sounds began to come from the motor backing off the throttle.
maybe now I can guess that it was because that the engine had'nt been balanced after CB shaft removal that this led to my oil pump failure.
Presumably this is from the vibrations that you experience at various engine revs or other reasons?.certainly it was a lot more "revvy" once they were gone as well...

I never did find out the bottom end diagnosis cos the bearings looked fine ...maybe I examined the wrong spot,if ever i get the time its in the back yard somewhere!

ps if you want I have a instruction of how to install the kit that came with it.About 10 pages with diagrams.J

[stealth]

jeez im going to have a rant here as i cant hold back
maybe the people with oil pressure and pump dramas should have a better look at
there pile of shit and set there clearances better in the fisrt place
there is NO REASON for a high volume pump NONE AT ALL
if your engine bearing clearances and oil pump (in other words build your engine
properly )there is no problems taking a astron to 7500rpm all day ,your more like to
shag rings
but as cheater said there is no need for this
i hate to break it to you guys but set your engines up better and these issues wont occur
rant over
cheers stealth

[Billsy]

ok , just to jump in on several leads here.

ill start on the actual topic. balance shafts
ive just fired up my new engine tonight and with no balance shafts i am definitely getting that Buzz (actually a very loud horrid vibration) and the engine definitely doesnt feel as smooth.

now engine clearances, what clearances do you build your engines to stealth?

[stealth]

.0015 mains .002 max
.002/.003 rods
.005 crank float
.004/ .006 max rod side clearance
oil pump
rotor tip .004
rotor to cover .005
end float .003/.004
shaft to cover .002 max
and for the vavles .001/.003
this is what i run my engines at but always pay the money and have you bottom end
balanced by a pro who knows what the f--- he's doing
rather than the local shop that will just take your money
cheers stealth

[Rallyant]

One of the pros is you can go back to the Oil pumps these motors were designed to run, the oil pumps the astrons used before the balance shafts were invented.
I have not done a back to back dyno, But im told you also gain some significant HP with these pumps over the gear style pump, the gear style sap more power than these ones. ?

[Rally_2.6LC]

Stealth, fair rant.........
How much (ball park figure) does balancing cost when it is done properly? I just want to know how many hundreds im looking at?

Rallyant, what brand of pump is that, where did you get it and how much was it?


Cheers Matt

[rob440]

I have been following this thread. I have the ebay balance shaft elim kit. My motor is a stock astronII and I will be removing the b/shafts in the next week or so. I would like to get my hands on the oilpump pictured above. Does anyone know where/what they are?

Rob

[stealth]

yeah thats sir is a forklift oil pump
designed for no balance shafts costs about $500
and supplys that same amount of oil as a std sigma pump
but is cast iron (for extra weight)and would last longer
but there is nothing wrong with the sigma pump
just make sure that you block off all the oil feed to the balance shafts
and as long as you have a decent bottom end no probs
cheers stealth