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Aussie Roller Cam


Tim_C.
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Truly plotting the profile requires expensive machinery. Too many things are going on at once to actually map the profile from a mock block. You can get close though, and maybe that's all we need?

 

I really don't think more lift is needed. .432 is plenty. More will require 120Lb valve springs (seat pressure) If we do more lift, it should be the exhaust valve only, but I believe that can be accomplished by widening the duration on only the exhaust valve. Pretty much that is all we need. A wider exhaust duration and less overlap along with a later centerline if possible, but it all depends on how much is required to take off the base to do it. We can do anything with a blank billet to work with, but we are talking grinding an OEM roller cam core here. Schneider actually has a decent set of roller cams with blank billets. Problem is big money, lots of time to grind, and maybe they can't do it any more? All I know is my .510 lift Schneider runs like a raped ape, but cost lots and lots to just get set-up. Custom valves, fly-cut pistons, custom VC gasket to clear the higher lift from hitting the VC. That is with hyd rockers. I think the mechs stick out even further if I remember right.

I agree with Glenn that a mech roller rocker would be the ultimate, but also must be made to take a serious beating and adjustments would be quite frequent.

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Truly plotting the profile requires expensive machinery. Too many things are going on at once to actually map the profile from a mock block. You can get close though, and maybe that's all we need?

 

I really don't think more lift is needed. .432 is plenty. More will require 120Lb valve springs (seat pressure) If we do more lift, it should be the exhaust valve only, but I believe that can be accomplished by widening the duration on only the exhaust valve. Pretty much that is all we need. A wider exhaust duration and less overlap along with a later centerline if possible, but it all depends on how much is required to take off the base to do it. We can do anything with a blank billet to work with, but we are talking grinding an OEM roller cam core here. Schneider actually has a decent set of roller cams with blank billets. Problem is big money, lots of time to grind, and maybe they can't do it any more? All I know is my .510 lift Schneider runs like a raped ape, but cost lots and lots to just get set-up. Custom valves, fly-cut pistons, custom VC gasket to clear the higher lift from hitting the VC. That is with hyd rockers. I think the mechs stick out even further if I remember right.

I agree with Glenn that a mech roller rocker would be the ultimate, but also must be made to take a serious beating and adjustments would be quite frequent.

 

I work for a company that makes measuring equipment. The primary product is optical encoders used to measure rotation and linear distance and another device is a data logger to bring the info into a spread sheet. Did I mention that a group of us that work there are car guys? And that one of my side projects is to work out a software / hardware package to measure cams?

 

The fun thing is the platform for the project is the magna head I bought :)

 

The data aquistion box is a FPGA based logger that brings data to a USB port. Really slick setup.... I should have the head in a few weeks and can test cams very quickly.

 

 

 

Kevin :)

 

 

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Sweet! I was going to send a couple of cams to my grinder to measure but I won't need to if you are doing it. I probably will anyway so I can get his opinion on how to improve it.

Another reason I don't want to add lift is that alone will reduce base considerably. The more loss in base means less chance of it bolting right in. I've seen stock cores that won't preload the lifters on a different head. Point being, we are already dealing with a non-adjustable set-up. Even though I have improved my shims to be stronger and work better than before. I want to really minimize base reduction unless absolutely necessary. The main thing is to widen the lobe separation. If we only did that, it would keep the RPM range the same on boost but it would lose a little low end. That is my main concern, to try and keep low end power. To do a good SOHC turbo grind, you pretty much have to lose some low end. That is why the stock cam can perform fine to 5000RPM or so. It has great low end power, and with the right combination of mods, it can retain a decent amount of power to 5K. It just takes a lot of mods to do it. I want something that doesn't lose much low end, but will also provide power up to 6500 or so without having to run MPI and tons of boost to do it. It may be impossible, but I already have cams that have great power up high. I only have one cam that performs well on both ends and it is a mechanical slip rocker. It outperforms stock on both ends with or without mods. A bolt-in roller that retains low end is kind of what I'm looking to come up with.

Yes, these Magna rollers are for a naturally aspirated engine. I plan to simply bolt one up to see what it does. It may be fine for both street and strip the way it is? An OEM roller is bound to be a big improvement over any stock slipper cam.

 

 

 

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Chip it took a few years for that gp to become a reality,,back in the summer of 99 talk was just begining , any way 10 yrs is a long time on a car forum ,

i remember Cookie (aussie member ) did leg work going to the yards and looking at a posible intake and gave me the phn number to them so i could order me one and take a look first hand at it

a cheap intake and later the comeing along of a cheap ecu made it very posible for nearly any one to go MPi , props to all that had a hand in that comeing to be

 

and DC thanks but i'm not the man for that,, Tim C and Chad are far better at

working up a cam set up , me i just ask dumb questions ;)

 

I don't think it was quite '99, at least not publicly, but uh, considering I'm the one that originally found Glen's site, contacted him and ran the first GP for Magna intakes, I think I'm familiar. I was just trying to get Dc to stop calling someone younger than me an old timer.

 

 

edit: It's still in the GP section here http://www.starquestclub.com/forum/index.php?showtopic=24458 The oldest thread in the GP section. I couldn't even remember if the GP ran on this site or the previous one. I think mention of it started over there and migrated here with the site change. There's mention of the timing of it all in post 38, where on 16 Jun 2002, I say the GP started 9 months ago, which obviously would have been late 2001. If someone else was working Magna intake options prior to that they did it privately.

Edited by chiplee
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i recive'd my magna intake 1st week of feb 2001 after months of scearching for the right oem intake and shiping took nearly 5 weeks , so it was ship'd in 2000

i wasn't trying to take any thing away from your's and Glenn's efforts in comeing up with the GP

i remember the time real well cause 1 week later i went into the hospital with a heart attack and bypass sugery

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TurboRaider(Kevin) perhaps you'd be interested in one of our local SQ meets?? (Saw that you're in Portland)

 

So, I'm guessing that grinding a cam out to the roller specs is not possible??

 

-Robert

 

Going to one of your meets would be great.... Let me know the next time you have one.

 

Kevin

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i recive'd my magna intake 1st week of feb 2001 after months of scearching for the right oem intake and shiping took nearly 5 weeks , so it was ship'd in 2000

i wasn't trying to take any thing away from your's and Glenn's efforts in comeing up with the GP

i remember the time real well cause 1 week later i went into the hospital with a heart attack and bypass sugery

 

 

I didn't think you were, not that I would really mind either way, and I don't doubt that timing one bit. A few members had heard of these intakes when I posted a picture of it on the old site back in 2001 sometime and asked why we weren't doing a GP for these.

 

But you said it took a few years for "that gp to get going", which made me think you were talking about Glen's very first GP, which was the one I coordinated from this end, and it didn't take a few years to get going. This is all kinda' pointless other than for posterity's sake, because the whole point of even mentioning any of it was to jokingly say I didn't like Glen being called an "old timer".

 

But it does raise an interesting question. Sooooo, Shelby, you kept a secret from us back then ehh. Ok, I see how it is.

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Great thread, I look forward to good results from this collaboration. For my part I'll add pictures.

 

http://www.picturehosting.com/images/oblique9881/cams01.jpg

 

http://www.picturehosting.com/images/oblique9881/cams02.jpg

 

Also did some measuring installed on my M7 head sitting on the bench. The USA stock cam using mechanical rockers set to 0.003" clearance gave exactly 0 degrees of overlap while the Aussie roller with 1.6 ratio hydraulic rockers gave a consistent 35 degrees of overlap. Overlap being that period where both valves were off the seat by at least 0.001" with the dial indicator sitting on the valve spring retainer.

 

Scott

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Also did some measuring installed on my M7 head sitting on the bench. The USA stock cam using mechanical rockers set to 0.003" clearance gave exactly 0 degrees of overlap while the Aussie roller with 1.6 ratio hydraulic rockers gave a consistent 35 degrees of overlap. Overlap being that period where both valves were off the seat by at least 0.001" with the dial indicator sitting on the valve spring retainer.

 

Scott

 

 

Did you run this cam on a turbo motor? What boost level and how did it perform? I thought for Turbo motors Overlap was bad. 35% seems like a lot. I like the small cam lobs :) sweet.

 

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Nope, bought it and plan to install it but haven't yet. It's on my list but there are a few other key things in front of it so maybe this summer pending what happens in this discussion. A couple of other numbers and let me state up front I've never made these measurements before so they are suspect until confirmed; seat to seat (0.001") intake duration 292 degrees, seat to seat exhaust 304 degrees, all degrees are crank degrees using 1.6 ratio hydraulic rockers including the overlap in the previous post.

 

Hey Shelby, or anyone else with experience, I can see why the roller rocker couldn't cope with the slipper cam lobe profile but it would seem the roller profile could be acceptable to a slipper rocker? Longer gentler ramp opening and closing and less abrupt going over maximum lift, seems more universal but its not done so I'm obviously missing something. Do tell.

 

Scott

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Nope, bought it and plan to install it but haven't yet. It's on my list but there are a few other key things in front of it so maybe this summer pending what happens in this discussion. A couple of other numbers and let me state up front I've never made these measurements before so they are suspect until confirmed; seat to seat (0.001") intake duration 292 degrees, seat to seat exhaust 304 degrees, all degrees are crank degrees using 1.6 ratio hydraulic rockers including the overlap in the previous post.

 

Hey Shelby, or anyone else with experience, I can see why the roller rocker couldn't cope with the slipper cam lobe profile but it would seem the roller profile could be acceptable to a slipper rocker? Longer gentler ramp opening and closing and less abrupt going over maximum lift, seems more universal but its not done so I'm obviously missing something. Do tell.

 

Scott

 

Were you using the aussie roller rockers to measure aussie cam specs? or the same slipper for both? Because the curvature on the slipper rocker changes the opening and closing timing (and overlap?) compaired to the roller rocker.

 

PS. you can see the roller lobes are way thinner than the slipper can. Does this mean they are made from a totally different cam blank than slipper cams? Maybe different or harder material too?

Edited by PDX87Starion
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sliper rockers can not be use'd to measure any thing on a roller cam,,

the slip rocker is not a center contact rocker ithas aprox a patch 1/2 inch long that does the rideing on the lobe

 

intial contact point with slip rocker (toe)___center____(heel), where as the roller only has a "." (center of roller )as lift , center and trailing point

the slip rocker starts out by the toe contacting first and rideing up the open ramp, when it reaches the top it sides across the wear surface maintaining nearly the same lift the entire time , and starts down on the heel on the closeing side of the slope , while the cam lobe is very point'd the actual valve full open point stays at full lift for a good while

 

a slip rocker on a roller grind cam will open way early and close way late , causeing the duration to be extra long , as you found in your test

 

magna roller cam specs should be easy found in your repair manuals as for duration open and closeing points ,lift etc

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But it does raise an interesting question. Sooooo, Shelby, you kept a secret from us back then ehh. Ok, I see how it is.

................................................................................

...................................

 

 

 

secret no way , i post'd the first pics i know of of a magna head that was here in the US ,,my only problem was heart trouble and 10 months of being unable to do any thing and no work meaning no pay for almost a full year

 

not meaning to take any credit away from you at all you and Glenn did a super job of geting things rolling , me i never talk'd to Glenn at all untill later when you and he was geting the GP going , i had talk'd with an aussie guy name'd Cookie he had an 83 starion

 

it was 4 yrs befor my intake was on an engine

 

 

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man i had a hard time finding these but they are pics i frist took of my magna head when i got it back in feb 2001

 

http://www.26liter.us/gallery/albums/userpics/10009/May14_12.jpg

 

 

http://www.26liter.us/gallery/albums/userpics/10009/May14_09.jpg

 

 

http://www.26liter.us/gallery/albums/userpics/10009/May14_06.jpg

 

http://www.26liter.us/gallery/albums/userpics/10009/May14_01.jpg

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Also, a slip rocker will destroy a roller cam very quickly, and probably the rocker, the rocker shafts, the journal caps and head. All in the first few secnds of run time! It's the other way around. A roller rocker will follow any lobe easily. A slipper might not make it around the roller lobe.

 

Our USA stock cams are made of the same material used in Japan on new OEM roller cams today.

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Hey, your an old timer chip! :)

 

I have only just recently noticed that on a lot of the other forums i am on, there are very few members left that have been around for more than 4years.

 

 

Hey, don't think I won't show up in AU one day, fugger. :biglaugha: I was almost there in 2006 but the dinks in VMFA-212 took that det from us.

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To be clear and it seems I wasn't, the measurements made on the stock slipper cam were using a mechanical slip rocker set to 0.003" clearance, the measurements made on the aussie roller were done using a 1.6 ratio roller hydraulic rocker. The ratio may be incorrect for the Magna application, that's still unknown, but the correct type of rocker was used appropriately. Roller for roller, slipper for slipper.

 

Scott

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To be clear and it seems I wasn't, the measurements made on the stock slipper cam were using a mechanical slip rocker set to 0.003" clearance, the measurements made on the aussie roller were done using a 1.6 ratio roller hydraulic rocker. The ratio may be incorrect for the Magna application, that's still unknown, but the correct type of rocker was used appropriately. Roller for roller, slipper for slipper.

 

Scott

 

I'll do some more measuring of base circle too. The base on the roller in the pictures looks much bigger. That means we have a lot more room to grind to reduce overlap. However, I measured the overall lobe height and it was only .1 more than the manual says the stock cam should be. I just got back home last night (this morning), so I will try to get everything out and do some more measuring today. I'll simply write down the numbers I get and post them.

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We definitely need to wait for Kevin C's measurements. All I can get are rough ones with some digital calipers .

AUS Roller cam:

I came up with a 1.495 Base circle measurement.

A 1.768 total lobe height.

This gives a lift of .436 with a 1.6 ratio rocker.

Journal = 1.339

 

USA :

Base circle is 1.380 or so. So basically a .115 increase in base with the AUS roller cam.

Total lobe height is 1.673 ('83 Mech spec) or 1.6693 ('87 Hyd spec).

 

I found this note I got from someone, but I didn't keep who it was that sent it to me so it may not end up being correct:

Magna Roller Camshaft Specifications:

Inlet Opens 25º BTDC

Inlet Closes 61º ABDC

Inlet Duration 266º

Exhaust Opens 66º BBDC

Exhaust Closes 20º ATDC

Exhaust Duration 266º

Overlap 45º

Inlet Cam Lobe Height 42.50mm

Exhaust Cam Lobe Height 42.56mm

Nominal Cam Lift 10.50mm

 

USA Stock Hyd cam from '87 manual:

Valve timing

INT Open (BTDC) 25*

INT Close (ABDC) 59*

EXH Open (BBDC) 64*

EXH Close (ATDC) 20*

Valve Overlap 45*

INT, and EXH Duration 264

 

I don't have it set-up on a head so I can't do any direct rocker comparisons. I can say that the AUS rockers are indeed a different rocker than the 3.0L V6 rocker and the 2.0L rocker. I removed the lifter from the rockers of a 2.0L SOHC 1st Gen Eclipse engine (known 1.5:1 ratio), and the AUS, and the 3.0L V6 (known 1.6:1 ratio). I held the lifter hole end flat on the edge of a bench with the rollers hanging off the edge, and observed the depth of the roller at the tip. As I already knew, the 3.0L rocker protrudes lower (more) than the 2.0L rocker. However, the AUS rocker was in between them as far as protruding depth. This says nothing about the ratio, but does say that the 1.6 ratio rocker will preload the lifters more than the AUS rocker.

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hehehe yeah 32 is defiantly starting to hit the hi side of 20s :(

 

Come on over chip, come out with us oneday, see if you can fly a real aircraft :)

 

 

I'd probably kill myself. I'll take two 22,000lb thrust problem solvers out back thanks. No riding the whim of the wind for me.

Edited by chiplee
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Tim if that info you post'd on the magna roller is acurate it's perfict for what i want,, but this 1.6 and 1.5 ratio on the rollers is some thing we need to check out,, where did they make the change at , in the roller to shaft axle pivot point or the valve stem side,is it a bit longer , or a slight bit of diff on both sides,, if the diff is on the valve stem side thats perfict as it won't change cam timeing

 

i'd suspect the roller arm side to be slightly shorter and the valve stem side to be slightly longer , that would not hurt any thing cause most set ups tend to be too far from the valve stem any way , but we'l have to wait and see but it sounds damn promissing

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