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So this is for my friend's car. He has a "previous owner built up" motor that he just had rebuilt. Running stock throttle body setup with an aftermarket larger turbo. So its got an Aussie mechanical head. Supposedly its got a 29x cam. Cant tell for sure without pulling the cam out. I'm guessing forged internals and all the goodies.

 

I cant get the distributor set closer than 15btdc. My reading says that if I pulled the dist. and moved it a tooth, based on the degree and tooth count it would move to 5dbtc. Basicly I understand this is a timming issue. I didnt build the motor, so I cant tell how much or if the head has been cut. Maybe the block has been decked? Who knows, but my understanding points to the timing chain being off due to the setup paired with a reground cam resulting in timing problems and him reporting ehh power. Adjustable cam gear is on the way. Now what gentleman?

 

I'm not sure how to degree this thing. No cam card. I read something about degreeing with a dial? That any good? I feel with a motor built to such a high standard and mpi in the near future, anything less than perfect in this case is a waste.

 

All help is greatly apreciated.

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So this is for my friend's car. He has a "previous owner built up" motor that he just had rebuilt. Running stock throttle body setup with an aftermarket larger turbo. So its got an Aussie mechanical head. Supposedly its got a 29x cam. Cant tell for sure without pulling the cam out. I'm guessing forged internals and all the goodies.

 

I cant get the distributor set closer than 15btdc. My reading says that if I pulled the dist. and moved it a tooth, based on the degree and tooth count it would move to 5dbtc. Basicly I understand this is a timming issue. I didnt build the motor, so I cant tell how much or if the head has been cut. Maybe the block has been decked? Who knows, but my understanding points to the timing chain being off due to the setup paired with a reground cam resulting in timing problems and him reporting ehh power. Adjustable cam gear is on the way. Now what gentleman?

 

I'm not sure how to degree this thing. No cam card. I read something about degreeing with a dial? That any good? I feel with a motor built to such a high standard and mpi in the near future, anything less than perfect in this case is a waste.

 

All help is greatly apreciated.

pull the valve cover and line the dots up

fyi, if you have a reman distrib, they put the gear on backwards, if you knock the pin out, flip it, then pin it, itll line up

 

 

also, did you tell him the aussie heads coolant port is different from the usa intakes port

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We fixed that. I custom cut an intake gasket for it and he had his welder guy modify the intake to work. Its been running fine. The dizzy was on the car with the previous motor he had so I doubt the gear is off. Then again maybe no one noticed or cared it wasn't right either. Ill look into that next time I mess with it. Still need to degree the cam regardless to optimize the performance of that built motor. Especially since mpi is in the works soon. Edited by Malykaii
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To do that I would use a dial caliper or would it be easier to pull the cam.

 

well I'm not sure how to answer that,, you do not have a clue as to what your talking about doing ,, the cam was out of the head at one point if ID numbers were on it,, they should have id'd the cam for you right off, with no markings your left with using a degree wheel and measureing the actual lift

points and close point then counting up the total duration of the cam

a little more research is in order for you at this point

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Well the problem is just that. I don't have a clue. Research isn't helping cause I cant find any info for my situation. Everything I read kind of assumes I already know how to actually do this. Ive even looked at a few cam cards and what not.

 

The cam probably was out of the head, but its not my motor and I was not involved with the build. All I know is the owner is confident its a 29x type cam. What I was asking is it best for me to remove the cam and find markings or [i read up on a method of] using a dial indicator to measure the duration. The head is a magna so I believe it has roller rockers and is mechanical. Since thats a pretty uncommon setup I doubt I'll be able to find anyone here who even has that cam card to post.

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not a problem but lissen , no matter who told you , roller rockers will not work with a slipper cam , and as of yet I have never saw a roller rocker with solid adjusters , this going back over 15 years on here

 

only 2 ways I know of to have a roller grind cam , a stock magna or one of Tim C's regrind rollers

 

now if you want some advice from me where you are now you have no neeed for a 29X any thing cam , that comes a bit further up the learning curve from where you areat now , and running a 29X cam makes an after market ecu almost a must

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I'm running a stock set up with the original 12a in my montero. So it may be out of my learning curve. I understand that.

 

However this isnt my car or motor. There are no performance shops that I know of in nyc. Otherwise it would be easier to drop the car and the adjustable gear off and be done with it.

 

Motor background. The current owner bought this build motor from some one on here and had it rebuilt. Forged internals, magna head, big turbo. Other goodies. Mpi is in the works. Since it was build by someone else initially, i cant exactly ask to see the receipts of all the parts in the motor. Hence all this speculations.

 

Don't magna's come with 1.55 roller rockers with mechanical adjustment? I just googled and confirmed. Heck for all I know they could have been switched out to non stock 1.6 ones. I just don't know with this motor.

 

My question, so if Tim was the only one.making cams for this type of setup, did he mark his cams or should I use a dial gauge and find the duration myself?

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I'm running a stock set up with the original 12a in my montero. So it may be out of my learning curve. I understand that.

 

However this isnt my car or motor. There are no performance shops that I know of in nyc. Otherwise it would be easier to drop the car and the adjustable gear off and be done with it. Hence I'm just trying to help a friend out.

 

Motor background. The current owner bought this build motor from some one on here and had it rebuilt. Forged internals, magna head, big turbo. Other goodies. Mpi is in the works. (I think he already has the ecu and intake) Since it was build by someone else initially, i cant exactly ask to see the receipts of all the parts in the motor. Hence all this speculations.

 

Don't magna's come with 1.55 roller rockers with mechanical adjustment? I just googled and confirmed. Heck for all I know they could have been switched out to non stock 1.6 ones. I just don't know with this motor.

 

My question, so if Tim was the only one.making cams for this type of setup, did he mark his cams or should I use a dial gauge and find the duration myself? Lastly, should I adjust the valve lash before or after I degree the cam, or both?

 

Again, thanks for taking time out of your day to help out.

Edited by Malykaii
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one real touchy part is finding TDC,, now you can count on the oreg tdc marks to be very close ,, when doing this you MUST stop valve action to all valves one #1 cyl , easyest way is to lossen the rocker arm assy you'l need a long piston stop aprox 70mm long

lets see if pics will load

 

http://www.26liter.us/gallery/albums/userpics/10009/Jan08%5E06a.jpg

 

a 70mm stop should stop the piston at aprox 25 befor tdc , you adjust your pointer till both before and after tdc numbers match , once

you have both numbers matching , turning the crank to tdc puts you at exact TDC

 

oh yea do not install a piston stop at tdc or close to tdc

 

http://www.26liter.us/gallery/albums/userpics/10009/Jan08%5E05a.jpg

 

in order to have a flat surface for the dial indicator i bolted a metal bar across the cam tower , now the top of the valve retainer is not flat eather but a thin flat magnet works great

preload the dial indicator ..500" or so then find the flat on the cam lobe base set the dial to 0

 

maybe a better pichttp://www.26liter.us/gallery/albums/userpics/10009/Jan08%5E04a.jpg

 

once you have the degree wheel on the crank made sure it is tight enought to turn crank in both directions , also if your timeing chain and guides are not up to par stop wasteing your time

 

ok you now have an exact TDC mark , bolt the rocker arm assy back down ,,all you need to do now is to make sure the lifter has (0) lash , with a hyd lifter bleed the oil out of it and place feeler gauge arms under the end to obtain a zero lash

rotate the engine and watch the dial indicator for any movement

stop the instant you see valve movement and record the numbers , contine rotateing the crank untill the valve reads 0 again , take note of that number,, do this 4 or 5 times untill yu get the same number every time , read the degree wheel and add up the degrees the valve was off it's seat

this is you open to close full duration reading from that you can tell what cam you have

 

with out a special adjustable cam gear your simply doing this for info only,,

 

none of this is hard but it can be frustrateing like a lot of things done for the first time

my personal opnion or what i like to do is set the cam 3 degrees advanced , timeing chains and gears a not static, they wear and what you have today and what the timeing is 10k later will be greatly diff,, and those 3 degrees give just a bit longer haveing the cam in time

 

the magnetic dial indicator stand and the dial indicator cost me less then $20 at harbor freight , piston stop you can make out of an old spark plug by breaking out the center and rounding a 8 mm bolt head and welding it into the houseing at the proper length , degree wheel can be hard at about any parts store

http://www.26liter.us/gallery/albums/userpics/10009/degree%20whl%20mark.JPG

 

any thing you need cleared up about , give me a ring or ask here in the thread so others can read it

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You know I was wondering just that. Awsome pic.

 

So this is the exact thing I was looking for. I work best with clear instructions/wire ups and couldn't find one on the topic. Not even in other brand forums. Thanks so much for the amount of time that must have taken.

 

Only thing that worries me is the motor is already in the car. Would have been easier on a bench. Oh well.

 

This truly needs to be a sticky or up in the instructions area for anyone in the future wanting to learn how to degree a cam.

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There's videos on YouTube of guys doing old Toyota R engines that cam help, too. Just search "Cam degreeing SOHC inline four" or something along those lines. I'd provide a link, but their server is down. It's fairly simple, as Shelby explained, just tedious.
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Another way to set your cam timing is to set your mechanical tapets, on #1 cylinder, to .050" (all cams come with the .050" lift spec). This way, it doesn't matter if the dial indicator isn't exactly vertical to the valve, you are only looking for when the valve initially moves.

Do this for both inlet and exhaust.

 

If there is a discrepancy between the cam spec and your results, you may have to re-check your TDC mark.

 

If you don't have a degree wheel, there is a rough way to check your cam timing is correct. At TDC on #1, with the rocker gear removed BUT a bit of tension on the timing chain, place a steel rule across the inlet and exhaust lobes. It should be level on a neutral (non-advanced or non retarded) cam grind.

 

 

 

Cheers.

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