hi all,
i have done a search but couldnt find anything that is easy enough to follow.

i am wondering if anyone has the knowledge to tell me if it is possible to change the cam timing on a 96 te 3.0L with stock cams
if so, how do i do this (please put in language anyone could understand) (ie. loosten timing belt and turn each cam 2 mm clockwise)

thanks in advance

Welcome to the forum!


Cams:
Why would you want to?
Do you know what cams do?
Do you know what turning the cams 2mm would do? What do you expect it to do?

Why would you want to?
Do you know what cams do?
Do you know what turning the cams 2mm would do?


Funny as it sound like you dont.



OP
you will need a set of adjustable cam gears if you do a search on this site Jasonsvrx has posted the part numbers up many times, once they are fitted you will need to get them adjusted and but i would suggest and after market piggyback ECU or tune from Steve Knight to get the full benifits

pretty sure that'll make it run like crap.
just get adjustable cam gears

Yep, get adjustable timing kit and adjust the timing - do dyno runs after each adjustment. You will find:

Retarding the standard cam timing will give you more low down torque but lose top end power.
Advancing will do the opposite.

You will also find that the factory setting is the best compromise between driveability, low speed torque and top end power.

thanks guys. i was only throwing the "2mm" remark out there so you would no the format of the info i am after.

by the sounds of it, i cant just move my cams and get free power. looks like i am getting some adjustable cam gears.

thanks again

Yep, get adjustable timing kit and adjust the timing - do dyno runs after each adjustment. You will find:

Retarding the standard cam timing will give you more low down torque but lose top end power.
Advancing will do the opposite.

You will also find that the factory setting is the best compromise between driveability, low speed torque and top end power.

The factory retards the cams eg 380 retard is 6 deg. The cams don't want any more retard. They need to be advanced!

The factory retard isn't for driveablity and low speed torque. Retard destroys low speed torque. The factory retards to help emissions and idle quality, and sometimes to lower transmission loads and help with traction control. Retard acts like EGR on closed throttle and lowers cylinder pressure. With manual transmissions the torque reduction can also make the car less jerky at low speed when going on and off the throttle.

Most engines work better at about 2-6 deg advanced from split timing. Personally for road engines I have found best results with the inlet lobe peak at about 104-108 deg ATDC.

The attachment is of an engine Graham recently was working on. The engine is similar to our Magnas and shows the result of cam timing changes. Most engines respond in a similar way. At half and quarter throttle the results are even more dramatic, which is why engines with retarded cams feel so sleepy and those with cams advanced feel jumpy and ready to go.

Adjustable sprockets are not required. The stock sprocket dowel hole can be filed. Every 0.21mm will change the cam timing 2 deg(crank deg) so to advance the cams say 8 deg only means elongating the dowel hole 0.84mm.

Cheers,
Alan

Yep, get adjustable timing kit and adjust the timing - do dyno runs after each adjustment. You will find:

Retarding the standard cam timing will give you more low down torque but lose top end power.
Advancing will do the opposite.

You will also find that the factory setting is the best compromise between driveability, low speed torque and top end power.

And yet agian your ability to spout utter crap has exceeded every expectation.....

As for the OP, read Alan's post as he has been there and done exactly that. His advice is about the best you will get.

And yet agian your ability to spout utter crap has exceeded every expectation.....

As for the OP, read Alan's post as he has been there and done exactly that. His advice is about the best you will get.



I couldn't agree more with you on both those points

love this site.

so allan, where are the hole i need to elongate.

is it the on close to the bolt, also, which way do i need to spin the cam sproket?

Elongating the hole is the easy bit.

Do you have the knowledge to remove the timing belt and cam sprockets, then replace these bits with the cam timing marks set correctly? Do you know how to measure the stock cam position, and then check the timing again after you have elongated the sprocket hole?

Make a mess of it and you mash the valves into the pistons!

If you are confident you can do it here is how:

The Magna cam sprocket has a slot to properly locate the sprocket on the cam. Most engines just have a simple hole, but that doesn't make any difference. The top of the slot is the bit that determines cam timing position. To advance the cam the top of the slot is filed on the right hand edge so that the cam moves clockwise relative to the sprocket. The cam dowel dia is only 6mm so you need a small round file. A chainsaw chain sharpening file about 5-6mm dia is good.

For detailed info a good free source is to go to the tech section of a site like Comp Cams. If you want to spend a few $ buy my old mate's books(thats one you owe me Graham), or look for them in the library.

Cheers,
Alan

Alan re cam timming on these engines how risky is it to go up or down one tooth on the cam gear just to try its quite tempting to do to see the result. Is there any chance of the valve hitting the piston by advancing the cam gear or retarding? Obviously the best method would be adjustable gears but i thought i would throw it out here for all... no matter how dumb my question would be lol...

How does advancing the cam timing affect torque/power output, driveability and emissions on the road?

Never mind, the graph explains it all.

Alan re cam timming on these engines how risky is it to go up or down one tooth on the cam gear just to try its quite tempting to do to see the result. Is there any chance of the valve hitting the piston by advancing the cam gear or retarding? Obviously the best method would be adjustable gears but i thought i would throw it out here for all... no matter how dumb my question would be lol...

Moving a tooth is way too much. From memory about 15 deg.

Adjustable gears are handy during dyno pulls but a waste of money otherwise, and some are none too strong for long term use with aggressive cams or valvetrains with harmonic issues.

As many know the Magna cams have been ground on different lobe separation angles. That means the front bank works better with around 2-3 deg more adv than the rear bank.

Milling the head and/or block also increases cam retard. Many makers specify only very small amounts of milling because they know how much the extra retard kills performance.

Piston clearance varies due to production tolerances so it is always safer to check unless you know the particular engine very well. I'm new to Magnas so can't accurately say, but as the factory cams are so mild I would not expect any problems with unshaved head/block. I suggest that Dave or Jason would know a lot more about valve/piston clearance.

Cheers,
Alan

i know how to remove timing belt etc (i have done the crank shaft seal), but not how to measure "stock cam piston"

so when i do this the cam sproket has to spin anti clock wise.

how much movement would give me more torquue?

thanks again

Moving a tooth is way too much. From memory about 15 deg.

Adjustable gears are handy during dyno pulls but a waste of money otherwise, and some are none too strong for long term use with aggressive cams or valvetrains with harmonic issues.

As many know the Magna cams have been ground on different lobe separation angles. That means the front bank works better with around 2-3 deg more adv than the rear bank.

Milling the head and/or block also increases cam retard. Many makers specify only very small amounts of milling because they know how much the extra retard kills performance.

Piston clearance varies due to production tolerances so it is always safer to check unless you know the particular engine very well. I'm new to Magnas so can't accurately say, but as the factory cams are so mild I would not expect any problems with unshaved head/block. I suggest that Dave or Jason would know a lot more about valve/piston clearance.

Cheers,
Alan
Thanks for the reply. I had an adventure with my vehicle pajero after i bought it same engine as the magna but some differences. We were chasing a loppy idle and after a lot of umming and arring and swaping things over we established that one of the cams was out by a tooth previous owner had the belt done and they obviously mucked it up. We corrected this with a new belt since we were in there already but after this i noticed the engine didnt rev out as quick as before and a slight hesitation but the engine runs very smooth since we sorted it. Wouldnt mind that low down power back again.
Might have to take it to my mech and rip those covers off and check things over again.
Regards

i know how to remove timing belt etc (i have done the crank shaft seal), but not how to measure "stock cam piston"

so when i do this the cam sproket has to spin anti clock wise.

how much movement would give me more torquue?

thanks again

To save me spelling out how to measure the current cam timing I would suggest that you have a look at the Comp Cams tech section or read Four Stroke Performance Tuning. You need dial gauge, degree wheel, good eyesight
and lots of patience to do it with the engine in the car!

To change the cam timing the sprocket isn't moved. To advance the cams the locating hole is elongated and the cam moves clockwise(forward) to open the valves earlier, and close them earlier. Opening the exhaust earlier gets wastes out of the engine faster so less power is used pushing ex gas out of the cylinder. This also can improve cruise economy. The big improvement though is from closing the inlet earlier. This traps more charge in the cylinder so the engine has more compression and makes more power. This also helps economy if you have a steady throttle foot as you need a little less throttle for normal driving.

It is impossible to say what cam timing is best for every engine. Just as all engines need slightly different ign timings, so with cams. Generally though I start testing most road engines with the inlet lobes set full open about 105-107 deg ATDC. That works for most engines. A deg or two more or less may be helpful but only dyno testing will show that.

Keep in mind that advancing the cam increases cylinder pressure and reduces ex gas recirculation, so the engine may want a bit less spark adv or more fuel octane.

Cheers,
Alan

People, if you know what you are talking about in this thread, post away. If you do not, STFU and just observe or ask logical questions.

If you give info that is up the spout you can potentially cause many $$ of damage to a person's engine.

If you have NFI about this, please keep an eye on this thread as people like Alan know what they are on about. This is a great source of information for all, even those such as myself who have done this sort of thing in the past. We can all learn more from those with more experience in a particular area.

Now back to the OP, when you use the OEM pulleys, it is a great way to experement with the cam timing but make sure you do use a torque qrench to tighten the pulleys back up again as they can come loose and slip.

As Alan said, a single tooth is way too far, I have not measuered a tooth but I would say 15 deg would be about the right amount.

Although the Magna engine is an interferance motor, you do have some give when you are playing, 2 - 5 degrees should be fine, any more than that and you start to get risky. For those who have seen an old belt on one of these, I have recently done a job where the front cam was a tooth out, car ran like a pig but no valve damage.

Before you do this though, please learn how to measure the cams on both front and back so as to get the benefit from the mod you are spending many hours on doing.

i moved the sproket 1 tooth clockwise:eek2:

it runs smooth, has much more power in low revs but dies at 5000.
there is no bad or abnormal souns coming from the motor. i will put it back to normal though, but do some sprocket filing
thanks

So was that on both cams, or just on one bank?

What model is your engine?

One tooth is way too much, depending on your engine most would only want about 4-6 deg advance rear cam, and 7-9 deg front cam. Ralliart and 380 cams are retarded 6 deg so probably need more like 6-8 deg rear cam and 9-11 deg front bank.

Cheers,
Alan

both cams. would it be advantageous to move the front one back and leave the rear one where it is

i figured it was only around 7 degrees per tooth as there is 48 teeth, and 360 degrees per sproket.
so 360/48 is around seven. is my reasoning flawed?

my engine is the stock te v6 3.0L 3rd gen

also, i dont have the resouces to dyno it, so, a ball park figure for the best power/torque would be muchly appreciated.

the motor is completely stock apart from k&n pod filter.

thanks

OK I don't have any knowledge of the 3.0/24valve 6G72 cam timing. Dave and Jason possibly know how far the cams are retarded. From what I've seen and been told by Graham with the Ralliart and 380 both cams are retarded 6 deg approx. Engines with the earlier cams probably have had different retard.

You may want to get a comment from Dave and Jason first but I would guess that a good starting point would be to assume the 3.0 ltr has 4 deg retard. So I'd file the rear sprocket to move the cam 6 deg(thats actually a true 2 deg advanced), and for the front bank I'd move the cam 9 deg. 6 deg= elongate hole clockwise to right by 0.63mm, 9 deg= elongate hole clockwise to right by 0.95mm, so it doesn't take very much filing. When you refit the sprockets just be sure to wind them back anti clockwise as you tighten the center bolt. Make certain you tension the bolt correctly.

Where you are going wrong with your 1 tooth calculation is that the cam moves 1 rev for every 2 revs(720 deg) of the crank. 720 deg divided by 48 teeth is 15 deg. Cam calculations are always relative to the crankshaft and piston position.

Cheers,
Alan

Gentlemen,
One of the best threads ever, along with the cam info in the 6G74 thread.

It seems to me that we can achieve a relatively quick and easy driveability / response improvement with the standard engine by a judicious amout of cam advance.
As an AWD driver I would really like to see an improvement with the very woolly low end.
I hate having to bury my foot on the accelerator to get the car moving in traffic.
I have been amazed at the difference between the Magna and a Mazda SP23 throttle reponse.

Seems to me that the ideal AWD improvement would be :-
1) Advance the cams.
2) Flow the throttle body.
3) Extractors and high flow catalytic converter.
4) Steve Knight ECU retune.

If more money is available then :-
1) Improved inlet manifold, the long awaited Streetfighter??
2) Carefull flow work on the heads
3) Up the compression ratio - either 9.4:1 Ralliart pistons or 10:1 Pajero ones.
Obviously matched to an ECU retune.

Gerry

ok everyone, the deed is done.

this easy mod is one of the best ways to get free power. takes only 2hrs.

definitley worked with the adjustments given by alan (all hale alan).

so here it is again. Do it if you want free easy power.

consider it done

This is a great bit of info guys, thanks ;)

I will be testing this mod on a sohc 24v 6g72 within the next couple of weeks when I get around to changing the timing belt, I will be posting results

OK, a bit of a heads up.

The cam gear modification was performed on a 6g72 in a 2005 MK triton.

Results are: a lot more induction noise and a lot less power, in what seems, throughout the entire rev range.

On paper the 2005 triton 6g72 was 133kw at 5250rpm, while the last magna (about 2002) 6g72 was 140kw at 5500rpm.

I'm guessing that the triton timing may not be so factory retarded as the magna was, as it seems I have clearly overshot the mark.

This may also explain why the ML triton 6g74, which was available up to 2008 or 2009 only had 135kw.

Either way, I would not recommend this mod in tritons, there is a bit more involved mechanically in accessing the goods also.

For those chasing more low down torque, triton cams could possibly be the answer

You will also find that the factory setting is the best compromise between driveability, low speed torque and top end power.

Just quoting myself here, from 5 years 4 months ago. lol

/start rant.

Why the fk would the factory NOT optimise cam timing for best performance across the range?

Whoever came up with the idea that the factory timing is NOT optimal, that blindly moving the cam gear timing relative to the crank would make the engine perform better across the rev range, needs to speak up and explain their logic.

And a few people need to explain why they accepted this idea.

(Engine builders who use adjustable cam gears and extended dyno runs with small changes in cam timing to find the best performance from the engine for its designed purpose, my carry on. lol)

/end rant.

Emissions is number 1 priority at the factory, well at least these days it is.

Why the fk would the factory NOT optimise cam timing for best performance across the range?a lot of manufacturers dull down performance from their engines in order to limit possible drivetrain abuse, mitsubishi are not alone in this aspect, I'm sure you have noticed the extended drivetrain warranties?


Whoever came up with the idea that the factory timing is NOT optimal, that blindly moving the cam gear timing relative to the crank would make the engine perform better across the rev range, needs to speak up and explain their logic.very little oem spec gear seems to be optimal, I wouldn't expect this to be any different


And a few people need to explain why they accepted this idea.I'm not sure what you mean, but factory tuning from mmc leaves a lot to be desired in many areas...

a lot of manufacturers dull down performance from their engines in order to limit possible drivetrain abuse, mitsubishi are not alone in this aspect, I'm sure you have noticed the extended drivetrain warranties?
very little oem spec gear seems to be optimal, I wouldn't expect this to be any different
I'm not sure what you mean, but factory tuning from mmc leaves a lot to be desired in many areas...

I'm sure that blueprinting an engine, dialling in cams, port matching etc can gain a few Kw, on any engine. But that requires flow benches, a dyno and many hours of workshop time. Do one change, then dyno the engine, and so on. Just changing the cam timing by one tooth in blind faith that the manufacturer of the engine (any make) has it wrong and you are about to unleash major horsepower, just isn't in the same league. More wishful thinking than proper engineering.

ok all, you'll have to forgive my previous posts, on re-opening the triton 6g72 and having a close inspection of things, I found that the apprentice had aligned the crank dowel with the timing mark instead of the actual crank timing mark, maybe my instructions weren't as clear as they needed to be...

Either way, even though I had advanced the cam timing with the small mod, being a full tooth retarded (I think) had negated that and then some, with the poor outcome which I posted previously.

I initially opened her up to re-set the cam gears, but ended up leaving them modded and simply setting the timing marks correctly.

The results this time around were much better, no noticeable change at idle, a slightly different note during mid range, and a bit more urge at bottem/mid range revs. Exactly what I was hoping for.

It will be interesting to see how the economy fares, I will post up results.

Thanks for the info guys

Nice, How much to you file off and was it the same on both cam sprockets?

On our 6G74 the service manual says that there is an adjuster for the front idler pulley.
There is no instruction as to how the pulley should positioned but it would seem to me that if the pulley position is indeed adjustable then moving it in toward the water pump pulley would effectively shorten the belt length and bring both cams forward relative to the crank. A lot easier than filing out dowels.
As 1 tooth is 15 deg. at the crank then only 1/4 tooth advance would be good.
Feel free to abuse me, I'm a noob with Magnas.

On our 6G74 the service manual says that there is an adjuster for the front idler pulley.
Feel free to abuse me, I'm a noob with Magnas.

Except that adjuster is for a different belt, it is for the alternator/aircon ancillary belt tension, not the cam belt.

No abuse from me,. too much of that on this forum as it is.

Thanks for that MadMax, looking at the exploded view in the manual it looks like it supports the Cam belt. Oh well, seemed a good idea at the time. I havent seen the mounting for the front idler, may a shrunk on sleve to increase the diamater a bit. Guesss a nice mod would be an eccentric mount like the tensioner mount.
Cheers

If you want to spend a few $ buy my old mate's books(thats one you owe me Graham), or look for them in the library.

Like to but whho is Graham and what's the names of the books?

Four Stroke Performance Tuning - A Graham Bell

Thanks for that WytWun, havn't forgotten the defs, just need time to work through the differences.

I have a question which you or someone else might know about.

Our crank angle sensor is nearly 5 Deg late, flashing somewhere between 0 and 1 Deg BTDC with the 5 Deg force set via Evoscan. The ignition timing can be fixed in the EPROM but the original performace / economy is not fully restored. Does the injector timing run off the ignition phase locked loop or is it locked to the Crank signal and thus is 4 Deg late, and is this significant?

Four Stroke Performance Tuning - A Graham Bell

Have the book now, excellent read, he takes an experienced practical approach to tuning.
Booktopia shipped in 5 days. Cheapest quote as well.
Thanks again.

Our crank angle sensor is nearly 5 Deg late, flashing somewhere between 0 and 1 Deg BTDC with the 5 Deg force set via Evoscan. The ignition timing can be fixed in the EPROM but the original performace / economy is not fully restored. Does the injector timing run off the ignition phase locked loop or is it locked to the Crank signal and thus is 4 Deg late, and is this significant?
Sorry, overlooked this. This is not an area I've gone into, but my understanding at the moment is that all timing (injection & spark) is based on the CAS signal, with the camshaft angle sensor (aka TDC sensor) used to identify which cylinder is #1. From what I understand the cam angle sensor isn't being used for base timing because advancing or retarding the cams (e.g. via adjustable sprockets) has no effect on this.