84 replies to this topic

[Mach 5]

Kev.. I will post the entire curve hopefully later tnite if I get around to it. I missed 1 increment of .050  but the rest is there and should still be able to build a chart with it.

[kev]

Cool.    This is all great info!

[kev]

Here is one of the emails I received from RPW.   Note the statement on 'custom' cams.  Didn't really take notice to this prior to your experience.

Quote

These roller rocker setups come off a standard Mitsubishi vehicle so they
will bolt right up without any modifications. They retain the same rocker
arm ratio as your existing setup.

Camshaft I would recommend the HKS style 272 turbo profile. Unfortunately
our camshafts do not come with camshaft cards and I can only provide you
with the most basic specifications only. But a 272 duration / 300" valve
lift is what we mostly use with great results.

If you want a custom profile we can make one of these for you, but we would
not be able to match it exactly, as we can only work off already developed
camshaft profiles so we would use one which is closest to the specifications
you would ask for.

Last email I received...a bit ironic being yours had fitup issues:

Quote

These are brand new billet camshafts custom manufactured to the same
specifications as the TS/TR magn.

So there are no fitting issues as such

[Mach 5]

ohh so I guess he changed his tune for you after I pointed out that he messed up on with me.. what a guy..

Jarek

[Mach 5]

The thing that gets me is I asked him initially for profiles and he said he could only do custom and that it wasn't an issue.. never that it couldn't be matched exactly. I would have been a little more understanding.. even more so if there was an actual spec or card

[Mach 5]

another thing is he says has had great results but has never used them personally.. see my emails. well I guess I will be the test bed for my cam spec

[Tim_C.]

Good luck to you guys. Like I said, the perfect cam will cost due to the need for more metal. Those processes aren't cheap and not many if any would want to pay the price. Plus, there is no such thing as the perfect cam that fits every application. Thus the need for different grinds. Grinds that were offered for years with good success except for the few people who were in over their heads and didn't know the basics of what is needed to set up a cam. The Aussie rocker works, but is a 1.55 or so ratio. It is between the 2.0L SOHC 1.5 ratio, and the V6 1.6 ratio. I'm sure the Aussie cam will work with a 1.6 ratio rocker, but it was close and I didn't feel like trying it since I had the 1.55 Aussie rockers with the cam. It seems to me that you are trying to re-invent the wheel when there are good options out there already, unless you want to spend the cash to make your own custom grind. Even then, you will go through a few cams before you get it right. Since my cam source was already posted by someone, I'll say that yes, he has a regrind that is basically the same as the Aussie stock roller cam. Call him up and he can grind it for you, no problem. I will say that it is very bad morals to post up someone's source without asking. However, I would have said that is fine since I won't offer anything ever again to anyone on these boards. Doing business properly seems to be a lost art with these new boys trying to build cars. Again, good luck, you are going to need it.

[Dad]

". Doing business properly seems to be a lost art with these new boys trying to build cars. Again, good luck, you are going to need it."

Top notch Tim,, I agree 100 percent.  Sorry to see this happen to you,  Dude just used you to make him out to be a big shot.. Real shame.

[88351wtsi]

Just wanted to say I appreciate the ones like Tim, Randy, and Scott, and of course many others that I have been able to contact for help that I take with confidence that their wisdom and integrity stands for something more than just words or smoke. We are a community here people, please respect and honor the ones that have been down the road and back a few times.  First hand experience from trial and error goes so much further than theories but after they have been tried by Starquest owners please post your results both good or bad. It takes a real adult to admit when they are wrong so anyone who says they have done this or that without proof.... Well it's like saying you made an omelette but you don't have any broken eggs to prove it.

[scott87star]

Quote

I'm sure the Aussie cam will work with a 1.6 ratio rocker, but it was close and I didn't feel like trying it since I had the 1.55 Aussie rockers with the cam.

I'll just add that I tried my Aussie roller first with the 1.6 ratio roller rockers and it held the valves open slightly, about 65-70% leakdown.  Switched to the 1.5 ratio and it runs fine.  I have not done any degreeing yet as my goal was to switch to a roller setup and get some run time on it, and I can say I like it.

[kev]

Well I sure feel like complete crap over this.

[Funky Phil]

As you should! I mean were talkin cars with zero parts support and even less research! You should feel horrible for trying to get what you want out of your project! How dare you share info on a web forum.

[kev]

Funky Phil, on 10 November 2015 - 06:21 PM, said:

As you should! I mean were talkin cars with zero parts support and even less research! You should feel horrible for trying to get what you want out of your project! How dare you share info on a web forum.

Haha, no not in terms of that.    I feel bad because my gut reaction to posting Tim's cam source was 'this is wrong' but I didn't do anything about it. Would have been so easy to just hide the post, shoot a pm to the OP, and request he get in touch with TIm prior to posting that info online.   At a bare minimum, it deserved a response to the thread saying just that.   Neither of which I did.



Haven't thought too much about cams this week.   I'm in a dilemma what to do.  I will back out the lift on the galant rocker vs the caravan rocker...just for the sake of it.    Still am left in a quandry as to the P/N of a magna roller cam.    Can't believe that I'm having such a hard time finding a parts list for the later 4g54 engines with this roller cam.

[Mach 5]

finally getting around to posting it on here. Sorry I took my sweet ace time in doing so... I hope this helps and I typed this correctly


Mach 5's RPW G54B Billet Roller "Custom" Cam

Intake Lobe

.002"/ -11.5*

.050"/ 7.5*

.100"/ 21*

.150"/ 34*

.200"/ 43*

.250"/ 65*

.300"/ 96*

.310"/ 111.5*

.300"/ ?*

.250"/ 158.5*

.200"/ 175.5*

.150"/ 190*

.100"/ 204.5*

.050"/ 220*

.002"/ 250*

Exhuast Lobe

.002"/ -74*

.050"/ -39*

.100"/ -22*

.150"/ -8.5*

.200"/ 5*

.250"/ 23.5*

.300"/ 48.5*

.312"/ 75*

.300"/ 93*

.250"/ 117.5*

.200"/ 143*

.150"/ 147*

.100"/ 157.5*

.050"/ 172.5*

.002"/ 204*

[kev]

Cool!  

I have some new info to share as well.   Thanks to the clever eye of Notstock88, I was able to acquire an OEM magna cam and roller rockers from a M6 used magna head.    

I'm having browser issues it seems, can't post pics.   But long story short is than md106245 is the part number for the stock magna roller rocker. Which is indeed the same as the exhaust rocker on the 2.0 SOHC galant engine!    Have tons of pics to prove it....coming soon.

The roller rocker ratio of this rocker is just under 1.55.   The lift is .405" with the magna cam.  Have the curves plotted out and will post as soon as I can.    But they are the same as Kevin C's plots.  

Never found the true p/n of the magna cam.  

I also tested the v6 rocker arms with the magna cam, as expected the valves are held open on the base circle.   The cam would need to be ground to work with those rocker arms.  Interestingly, the rocker ratio on the v6 arms was close to 1.7 using the magna cam!  

For now I'm building the engine with the stock magna roller setup.  I degreed it in at 3 degrees advance and plan on eventually playing with the cam timing on a dyno.   This will establish a good baseline.  I'll keep my eyes open for another magna cam down the road to regrind to use the v6 arms and a split duration....but that is far off.

I'll post my pics as soon as I can but I'm going to turn this over to you guys for I'm done with this camshaft science project.    My engine is almost built and I'm saving up for my turbo/waste gate.  Next debacle for me is to build the exhaust and intake piping.  

Kev

[kev]

Here are the photos showing the comparison between the brand new MD106245 rocker and the used rockers from the OEM M6 Magna head.   As you can see, they are geometrically the same.   I ran numbers on both the new rocker and the used rockers on the engine setup with the degree wheel..there are identical!  Same lift, same everything.  

Thus, the P/N for the OEM 4g54 roller rockers is MD106245.  This is the same as the exhaust rocker on the 2.0L SOHC Mitsubishi engine sold in the USA.  

















kev

[kev]

Here are the pics of the used Magna camshaft that I acquired next to a reground OEM cam (Monsta-Banshee).   I was very dissapointed to see the scarring on the wear surfaces.   But putting that aside for a moment; look closely in the pics, you can see the lobes are adjusted for the different contact location of the rocker arm.  













Prior to even placing this cam into my new head casting; I took it to a local machine shop whom polished the bearing surfaces.  They removed about .0005" of material which wasn't enough to completely remove the scores on the surface but what it did was smooth it out to eliminate any high spots.  The machinist assured me that there will be no issue with running the cam like this.   I still felt a bit uncomfortable so I had another local machine shop look it over and give me a second opinion (same answer).   After polishing, I'm still within spec on the oil clearance (~.0025 via measuring and double checked with plastigage).  Still may be taking a risk, but I will be running this cam on my build.





Finally, I cut off the knub at the end of the cam used on fwd applications and hand polished the cam lobes:

[kev]

The Magna cam has a base circle of 1.496".   Oblong dimension was 1.759 which means the cam provides a .263" lift.    My 'valve lift' measured via the dial indicator on assembly was .405".  This means the MD106245 roller rocker has a rocker ratio of 1.54.  (Note; I ran the numbers several times and .405 was the average of the trials..I had as high as .408)

Finally; here is the chart showing the Magna cam w/MD106245 rockers vs the Monsta-Banshee w/V6 rockers in addition to the Magna cam w/v6 rockers.   As I said earlier, the v6 rockers opened the valves on the b/c even with fully collapsed lifters.   The two lifters that I was using had slightly different collapsed lengths which is why you see a lower lift on the exhaust than the intake in the graph.  Although I didn't hunt it down further, I'm pretty confident that the max lift with the v6 rocker on the magna cam is .440" or possibly a hair greater (meaning a RR of 1.67 on the V6 rockers).




Should probably have taken more measurements than just every .050" lift but it told the story...ie the curves matched what Kevin C. posted using the cam profiler.  

The v6 rockers do contact at a slightly different location but note that the overlap is identical to the MD106245 rocker!  They result in a higher lift and greater duration without sacrificing the LSA too much (~2 cam degrees) and holding the overlap.  I believe there would be extensive gains by simply regrinding the Magna cam to accept the higher ratio v6 rocker...not even having to experiment with different lobe profiles.    But as I said, I don't have a baseline or a way to prove any gains...so I'll start off using the stock Magna condition and go from there.

kev

[Funky Phil]

Good work

[lionbull]

Glad to see this kind of documentation