84 replies to this topic

[kev]

EDIT:  This info was split from a thread in the VM forum....there is a lot of good technical discussion here that deserved its own thread with a proper title and in the proper forum.  



I had to step away from this topic and the site for a week to clear my mind.   It was obvious that I was leading this into a certain direction and I didn't want to start this into a huge argument.   I was upset that someone popped up saying he knew all about this issue and never spoke up...although in some regards, I kind of expected this to happen.   In all, I apologize for this and simply want to figure out a decent roller setup in an economical fashion.

I have what I believe is an Au roller rocker from a mid 90s Magna TS, it is part number MD106245.  I bought this directly from Mitsubishi years ago when Tim was just experimenting with roller camshafts.   I have yet to find a Magna TS parts manual and haven't been able to fully confirm it but found AU sites selling this P/N for the mid 90s Magna TR/TS application. I may be incorrect...if so, please correct me with factual proof (not meaning to be sarcastic, I honestly want to know).  Anyways, I put this rocker arm on my setup shown in the other post and it contacted at the same spot as the v6 rocker, MD195450.

I am interested to know more of your thoughts on this topic.  I'm interested in the numbers you are considering to offset the lobes to correct for the different contact point.   I have a pretty good idea based on what I recorded over the past month...my setup is still intact in my garage and I could easily spin the engine to do a sanity check on the numbers. I'm also interested in knowing where you found a solid billet camshaft for this car.  

Regards,
kev

[questtuner82]

Im still in the process of figuring the exact degreeing of the cam for use with the 3.0 rollers. The issue is that every grind has differences in lobe center. For my cam im going to figure out exactly how far apart the contact point is from a slipper to a roller then go from there. Theres a fraction that has to be used to figure all the changes out. I do believe that the slipper vs 3.0 roller contact patch is roughly .080" off maybe a little more which is roughly 8-12* off what the lobe center should be. As for the magna rollers i acuired a set when my mother was in the uk. She is a g54 gearhead herself and has been finding stuff in the uk every year when she goes there for work purposes. Not sure of part numbers but i can tell you that there is a difference between them and the 3.0 rollers. She has also acuired a set of billet roller rockers that were custom made with mech adjusters from a uk company that went out of buisness 3 years ago. Ive been trying to get her to send me some so my machine shop can replicate them. She wont come off them though. As for the billet cam stock. It was made by bme as that company is a sponsor for my two race cars. It took me three months to get the company to make me one with alot of nagging every week and cost me 450$ even with my sponsor discount. This is why i have to do alot of numbers research and roller research bc i want it to be correct so im not wasting 700$ on a custom cam.

[kev]

From the data I obtained from profiling the cam, I am getting just about 6 degrees delta (this is camshaft degrees, not crank).  If I advance the intake lobe by 6 cam degrees and retard the exhaust by 6 cam degrees, I get a lobe separation of 108.75 (with the Monsta-banshee cam).   The Monsta-banshee should have had a 109 lobe sep.   With my last data run, I had 119 intake centerline from about the center position of my cam gear (my camgear has no markings, so it was eyeballed).   If I wanted 107, the delta is 12 degrees in relation to the crank...further confirming the 6 degrees.
  

But I'd want to reconfirm all of this with greater attention to the absolute center of peak lift on both lobes prior to developing a cam.    When I took this data, I wasn't so concerned about the peaks but rather the overall profile including when the valves started to open/close.  

I don't believe the grinder can compensate for this much of a difference on a regrind cam...would need a billet like you have found.  But I didn't ask the question.  

kev

[questtuner82]

Regrinds can be compensated without any issues if the grinder is competent. Ive had small block chevy stock cams reground before and all they do is weld the area needed and after that they heat treat the cam before regrinding then another heat treatment is done before polishing.

[kev]

Is that how colt said they can compensate for this...weld overlay?

[kev]

The data Kevin C collected using the cam profile system  is another reason why I believe the AU roller arms aren't right.    Note the curves, the both cams follow very similar profiles regardless on the AU vs v6 roller rockers.  A slight difference in the exhaust, but very close.  


Red - AUS Roller Cam w/ AUS Roller Rockers
Black - Slipper Cam w/ AUS Roller Rockers
Yellow - AUS Roller Cam w/ V6 Roller Rockers
Teal - Slipper Cam w/ V6 Roller Rockers

[kev]

A source of the custom roller arms with mechanical tappets.  They've carried them for years and use to have them directly on their webpage.   Price was very high plus shipping.   Don't know anyone in the states who actually purchased a set.

Been in discussion with rpw on their cams....they won't even provide camcard info. Too risky of a gamble for me

http://shop.rpw.com....ker-detail.html

[Mach 5]

I have just experienced the service with David from RPW. I am very disappointed.. He will twist words to make a sale. The cam itself is nice but wont be a custom grind to your specs. I will be posting all emails and my full experience in a thread very soon. Basically the cam I ordered ends up being not what I ordered but is ground to whatever they feel like. This is why they wont provide a cam card.

-Jarek

[Mach 5]

Kev can you send me yer email addy? I want to send all the stuff I have from RPW.  I will be making this aware on here very soon so hopefully nobody else has an issue like me.

[scott87star]

I had contacted RPW over a year ago about purchasing blanks that we could grind here stateside, even in lots of 10 or 20 they wanted the same price as a ground cam.

[Mach 5]

they use a company called Camtech in aussie land. I think we need to contact them.  I did also run in to a problem with the large cam with the stock magna rollers.. the cam with the correct base circle actually rubbed the bottom of the rocker arm directly behind the roller. I had to shave the rocker slightly to gain clearance. I have some pix I will post hopefully later this week my findings. still haven't used the cam though since the car is going to the body shop

-Jarek

[kev]

I'd consider budgeting for an rpw cam if I had the added confidence that it would work.   My scare is that I'd me out hundreds of more dollars and in the same boat as I am in.    

I just want to know if the fundamental setup will work (cam profile, rocker arms, etc).  The performance increase is secondary for me at this stage of the game.  

I can't believe it is this difficult to find a functional roller setup for our cars that doesn't cost a fortune.  Especially being that Mitsubishi made factory 4g54 engines with roller setups!    

Kevin

[kev]

Mach 5, on 03 November 2015 - 10:31 AM, said:

they use a company called Camtech in aussie land. I think we need to contact them.  I did also run in to a problem with the large cam with the stock magna rollers.. the cam with the correct base circle actually rubbed the bottom of the rocker arm directly behind the roller. I had to shave the rocker slightly to gain clearance. I have some pix I will post hopefully later this week my findings. still haven't used the cam though since the car is going to the body shop

-Jarek

Interesting for sure!   I figured cam tech supplied rpw cams but their info doesn't match up right...May be just out of date.   Another reason why I'm nervous.  

Where were you able to get the magna rockers?   Was it from that ebay site posted a few months ago?   I think from a company called Kenny's or something like that?  

Did you degree in your rpw cam with these rockers?   If so did it take a major or minor adjustment?

[stariondreams]

Are these the rockers that you guys are looking for i just ordered a set I wanna try them .
http://www.ebay.com....k0AAOSwl8NVeCj8

[kev]

Yep, that is what I was referring to.   That is one of the sources where I was able to cross-reference the part number of the rocker I have (mentioned earlier).   I found another distributor in AU who mentioned the same P/N for the Magna TR/TS...

This rocker arm contacts the cam at the same spot as the v6 rocker (via the same method shown in my thread in the cam forum).





kennysholdenspares & MBS-auto
OEM quality at a fraction of the price. High quality rocker arms as good as the genuine product, in fact they are the same. You just don't get the mitsubishi part Number tag inside the bag.
These are not a cheap imitation as you may find from certain US manufacturers. These are identical to the OEM rocker.

Originally fitted to the Magna/Pajero TR-TS and are an excellant performance upgrade to the Astron engine from 1.8L to 2.6L, but generally fitted to the 4G54 engine.
The Mitsubishi part number is MD106245 selling at $56.40 ea = $451.20 for a set, but are no longer available from Mitsubishi.
This sale is for a full set of 8 rockers

Also available individually just contact me if you need less than a full set..

[kev]

Shame this ad doesn't have better photos.   But zoom in, you can see those rockers don't contact the center of the cam..

http://www.ebay.com....csAAOSw0HVWBKnu

[Mach 5]

yes that's where I got them from. Very nice guy to deal with.

the head be careful they have many generations of heads even some that have heart shaped chambers. not that the design is bad its prob very good in terms of quench.

[Mach 5]

the sohc gallant uses half of the same rockers as magna but rockauto didn't have a full set

[kev]

yes, same as the sohc galant 2.0....well the exhaust side.   That is how I found and bought the one rocker I had way back when.  Tim started trying to make the galant rocker work with the banshee cams....actually I believe he uses it on his schneider roller cam hybrid setup on his silver 87.    Just wish I could find a magan ts/tr parts catalog to fully prove this p/n was applicable for that car.  

i wouldn't buy that head, I was just trying to see the rocker in relation to the cam. What I really want is an oem magna cam....   Almost worth it to buy that head just for the cam but doesn't appear they sell to usa (AU listing only)  

kev

[Mach 5]

I did degree it. RPW uses a centerline method but I had nothing to base timing events off of so it will be a trial and error deal when on the dyno. I will say this it was a very nice cam but it was way off the specs I provided. not even close. I did try and graph the profile so I had an idea on what I was looking at. I will post that info also in the thread Im going to make. My main issue with the cam they provided me disregarding the part of it not being anything custom I asked for was that it has a small duration @ .050" lift. but not really sure the cam would fit if any bigger anyway due to the cam hitting both the lower part of the head and the bottom of the rocker. This would be fixed with a higher ratio rocker due to a smaller base circle.

I think funkyphil is coming out with a cam line btw

-Jarek