Roller Cam Dynamics 2

[Tim_C.]

The reduced base circle (.140 less) is a must for many reasons.  Most include longevity.  The lobe needs reduced to keep the action in it's wheel-house so to speak.  Like a pro baseball player hitting a ball with perfect timing.  The stock base circle would put more stress on the rockers and shafts.  

Also, for you guys who want more from their slip rocker cams:  You can put the 1.5 ratio roller tip rockers MD106245 on, and get the gains from the increased lift, and less resistance from the frictionless roller tip rockers.  James CNM used to sell those with his (really Schneider) cams. (The cam must be hardened for the rollers, but all of Schneider's are)

I have the new marnal head, and am getting the overall valve-length dims so I can get specs together and build another one from just new parts assembled, with little or no machining, except porting.  I think we can come up with the ultimate StarQuest head for under $1,000 if we assemble it ourselves.  If not, then I will still try to get another one put together with all new/virgin parts.  I should have mine going by the end of next week hopefully, but you know how those time frames go.  I want to prove it first.

Tim C.

[MidNiteRide89]

I think we can come up with the ultimate StarQuest head for under $1,000 if we assemble it ourselves.  If not, then I will still try to get another one put together with all new/virgin parts.  I should have mine going by the end of next week hopefully, but you know how those time frames go.  I want to prove it first.

 

Are you saying that if everything goes to plan, you'll be selling these?      

[Tim_C.]

Yes, but it won't be under $1,000 unless we find better deals on stuff.

The parts alone are already more than that.  I was hoping for better deals, so I'll keep trying.  

Marnal head: $315 (that's a GP price too) Comes w/studs, & cam caps (w/bolts for caps)

Roller Cam: $200

Dual coil springs: $125

Valves: $160

Rockers: $210

Rocker Shafts: $185 (Mitsu)

Lifters, retainer kits: $60

Well, that comes out to $1255

Guess I better start looking for cheaper stuff.  Those prices are what anyone can get them for. Melling makes a rocker for $4.00, but I haven't seen what it looks like. John sent one to me, and I should see it today. I will start looking into aftermarket brands to see what kind of quality & price they offer.  I want the parts to be under $1,000, or I don't think I can make 'em for a price anyone will want to pay.  I will use my friend's alternator shop to maybe get better prices on some of this stuff.  So, anyone know of alternative sources, let me know.  I will not be wanting to make a killing on these.  In fact, I will just want compensated for my labor.  That is about 1/2 shop rate, so we'll see.  I'm not in this to make money, unless I stumble on a product that goes for all cars so to speak.  No one will ever get rich if they just supply parts for the StarQuest.  We've sold about 20 alternators so far in about one years time, so that helps, but it won't pay the bills!

Tim C.

[MidNiteRide89]

Just the fact that you're doing this is a huge boost to the StarQuest community! We owe you thanks for doing something that will never make you rich!  

Keep me in mind once you have the details and tests finished. I'll pay $1k easy for it, same goes with the intake Chad has done. I just need to find a good '89 to stick next to my '83. (There are 2 I'm looking at right now    )

 

Heck, considering I just spent over $800 in the past few weeeks, on factory StarQuest brochures, postcards, plastic and small diecast models............  

Your head sounds like a downright bargin!

[kev]

Thats some good info Tim.   Did you find out what type of valves you need?  Are they the manley valves you wanted?   I got a call yesterday saying my rocker arms are in at the Mitsu dealer.   I got the same ones you have and also the arms for a 3.0 sohc engine.   I have yet to determine the rocker ratio on the 3.0 valves.   I need to get back on the ball on this, I have been focusing too much on the suspension of my car lately thus have been putting the engine to the side for the moment.

 

kev

[Tim_C.]

Yeah, John sent me a 3.0 roller rocker to compare too.  Doing that today. He sent a Melling version of it, and it looks very well made.  He says they are $13 each.  The Mitsu part number for it is MD195450. Is that the same as the 3.0 ones you have?

Well, my Marnal head should come together this week.  I am going to stick with the TEP valves & lash caps, since we have a cap w/a longer skirt, and .020 more height than the ones that slipped out.  Problem is that we will be grinding the new seats.  I figure as long as it lasts, it doesn't matter.  I am getting the measurements to order the correct lengths with a virgin marnal head so I can get another one put together.

Yeah, Manley is the only one who offers the hardened wafer tip on their custom length SST valves.  Titanium would be sweet too! It all matters what we want to spend!

Tim C.

[kev]

Yep that's the rocker I have for the 3.0.   I asked a few people on the 3000gt boards if they knew the rocker ratio of this arm, but no one knew.    I think the 3.0 rocker will work out better for geometry reasons but if the lift is less than 1.4, it won't benefit for performance reasons.    

 

I will be checking into the Manley valves when I finally lug this stuff up to my machinist to get his opinion and to start piecing the head together.

 

Thanks Tim for all of the info,

 

kev

[BuzzKill]

I'm running those rockers with the stock cam. Seems to be doing fine for the last 3-4 months since I put them in. Anyone know of a reason/issue why this isn't ok to do?

[Tim_C.]

OK, found out today that Mellings version of the MD195450 is a 1.6 ratio!!!!  So, that puts quite the lift increase to any 2.6 cam.  That puts the lift of my .476 roller cam at .544!!!  Way too much even for my blood!! He He! (Cam lift .340 X Ratio)

Gabe, it may not last long, and you should maybe check the lobes for wear.  You would think that there is less wear, but the roller is said to make a groove from more pressure on a smaller contact patch.  However, I have 2 stock cams, and they are a dime a dozen, so if they don't wear too fast, slap on another one!  Or, pay to get one hardened if it isn't too much. Or save $150 or so, and put the hardened upgraded cam in.

 

The Melling part# is MR925 for the Galant 3.0Liter Roller Rocker.  

 

I talked to Dan at 1-800-Melling  Technical Dept.  He had to look it up and call back with that 1.6 ratio figure.  I compared the two roller rockers, and the 3.0 one ends up closer to the valve and a tad shorter throw.  At first I thought that would make for less ratio, but now I see it makes sense for more ratio, since the rocker needs to turn less to get the same result at the other end.  It will get turned the same amount as the 2.0, or any rocker on the same cam, so the lift will definitely be increased.  We are checking the EXACT lift of intake and exhaust valves using each rocker to be sure.

Stay tuned, and one of these years we'll get there.

Tim C.

[kev]

Cool!   I have been searching on several Mitsubishi boards for the past three weeks trying to find out that ratio and here you find it in an hour!   I must be doing something wrong, lol.    I guess it just comes down to your connections.  

 

Yes a 1.6 ratio does sound a little high.  

 

kev

[Tim_C.]

We are checking the 1.6 rocker and some longer manual adjuster stock valves to see if that is feasible to use without lash caps.  If so, then a cam can be ground to our specs made for the 1.6 ratio.  Anyway, proof is in the pudding so to speak, and we are checking lift with both rockers to verify all ration info given to us. 1.5 for the 2.0, and 1.6 for the 3.0

If it works with stock valves, that will be the ticket for a much cheaper roller cam head. TheMellings are considerably cheaper. John said $13, but that is a dealer cost, or so Melling Denver told me. They said anywhere from $14-20. I can start an account with them and get them cheap.

More to come!!

[kev]

I did find out that the DOHC 3.0 engine uses a 1.72 rocker ratio.  Also I don't even think the geometry of the dohc rocker is even close to ours.  

 

kev

[MarioG]

Okay guys, this is something I've thought about.  I've been using the V6 roller rockers with Schneider's 284RH cam for some time now without any problems (except it developed a valve tap and I fear that a lash cap has come out).  Apparently, the roller rockers are different ratio than the stock 2.6 rockers, and based on what I see here there are a mess of different ratio rockers.  But, doesn't the fact that the camshaft and rocker shafts are fixed in position mean that the cam timing will change with different ratio rockers?  Think about it, for them to be different ratio there has to be a length change from the fulcrum (where the rockers pivot on the rocker shaft) and the point where the roller touches the cam.  In fact, if you even visually compare a stock rocker and a V6 roller rocker you will see that the roller rocker is identical on the valve side and shorter on the cam side (hence the higher ratio).  The problem is compounded by the fact that the intake and exhaust valves are on different sides on the camshaft, meaning that you cannot simply adjust the cam timing to correct for it, rather the cam must be specifically ground for it.  When I bought the cam from Schneider I was told that it was specifically ground for these roller rockers, but I think that they were only refering to the special profile needed to correct for the smaller diameter of the roller as opposed to the arch of the regular rockers.  What do you guys think, are these legitamate concerns?  

Mario.

[kev]

Yes very legitament concerns.  This has been on my mind as well.   Once I finally get a head together here, I will be first trying the Galant rockers out and I will have the machinist see if he can degree in the cam.   By degreeing in the cam, he will verify that the intake and exhaust valves open at the specified degrees on the schneider cam card.   I have been considering getting an adjustable cam gear to aide in this process.   If I can work out the geometry concerns and be able to degree in the Galant rockers then I will go that route.   If not, I will try the 3.0 rockers.   There are also the aussie rockers from rpw that I can resort to as well but they only use a 1.3 ratio.  

 

kev

[Tim_C.]

Well, the 3.0 V6 rockers are shorter on the valve side. We had the 2.0, & 3.0 rockers on the same shaft, and the valve side is shorter as far as from the center of the rocker shaft diameter to the center of the lifter hole diameter.  Also, the 3.0 puts the lifter closer to the valve, so it is more feasable to use that way.  Yeah, the difference should be able to be taken out with an adjustable cam gear if you really want to get perfect, but it would just make a little less at low RPM with the cam straight up, and hi-RPM's should be better. A little less at low RPM for a roller cam is still much more than any other cam.  Slight ratio increases should not make enough difference to cause concern, but what you say is true.  Maybe the 1.72 ratio one would be enough to want an adjustable cam gear?  Don't know.  All I know is that one is too different/big for me to want to try.  That would put the 284RH lift at .584!!!!

Mario- You may want to pull the cover to check for that cap, because when mine lost one, I drove it for 4 miles maybe, and it already started to deform the top of the stainless valve.  Unless yours are hardened tips.  What valves are you running?  Stock lengths?  What size caps?  We think stock valves from a manual lash adjuster head will work with the 1.6 ratio-3.0 rocker, and a large cap like .125"

It would be good to hear what you are using.  We are trying to figure this one out, so the StarQuest community will have a new, top of the line option available.  If all it takes is buying the parts and assembling them (w/minimal machine work), then I will start doing that for just compensation of my time in it, and get these heads out there.

Thanks,

Tim C.

[MarioG]

The valves are new stock replacements, so the tips must be hardened.  When I realized that the roller cam had such a smaller base circle I figured lash caps would be the easiest way to correct it.  Its been a while, but I think I got the Comp Cams .080" lash caps.  I'll have to double chack to be sure though.  They provided proper lifter preload, so I don't understand why they would ever come out.  What can be done to keep them in?

Mario.

[Tim_C.]

OK, Mario- The proper "preload" on these is deeper than a normal preload.  We had .040 preload on my first set-up, and it lost a lash cap. We were using the Crane Cams .060 cap.  They have a shallower skirt, and that contributed to why they came out on mine.  I now have the Comp Cams .080 caps. They have a deeper skirt that should not come out, but it won't work on a stock valve due to hitting the retainer.  That .040 is 1/3 of the way into the lifters complete range of travel.  Should have been more than enough.  We think the known lifter problem is the culprit.  These lifters like to lose their pump, and when that happens, it doesn't push against the cap tight enough to keep it in.  That makes for a problem that can be overcome with a bigger lash cap, or a cap that screws into a prepped valve(which we can't find yet), or a custom length valve w/a hardened tip.  Manley now offers that valve.  They didn't last year when I ordered mine. We also think the roller lobes are contributing to the lifter not holding its pump correctly.  Another alternative is to use manual adjusters, which need to be custom made, or that Aussie place has them I think, but there aint no room for'em under the valve cover, so a cover spacer (at least 1/4") is needed to accomodate that to clear the cover.

These are all problems that can be solved easily with a proper length valve. And flycutting the pistons! Unless you have a virgin head.  That should give enough clearance, but the 284RH cam really needs to be clay checked for clearance.  

Tim C.

[kev]

Tim,  I got my rockers yesterday.   I see what you mean by the 3.0 sohc rockers.   They look like the optimum setup when it comes to geometry but with a 1.6 ratio, the lift will be a bit too much.   However I am still going to set them up and find out the exact lift from both rockers.   The 3.0 rocker won't have to have the valve cover lifted most likely and using just lash caps on a stock valve will probably work.   But that lift is still large.   The 3.0 rockers are what hendu had on his head with the schneider 284rh cam, I verified the markings on the rockers last night.   He did not have a problem with the valves contacting the pistons or anything but his car only ran a few months before he parted her out.  

 

Oh btw, I got one 3.0 dohc rocker in yesterday as well.  It won't work, the whole rocker is about 0.5" long, 0.25" wide, and 0.25" high and weights about 3 ounces, lol.  It seems like the camshafts on the dohc setup are directly over the valves and this tiny rocker is the only thing between.  

 

 

kev

[Tim_C.]

But wait, there's more!!!:

Alternative options for setting up the Schneider 284RH Roller Cam:  Use the 1.6 ratio rockers, Melling part number MR925 (that puts the lift at .544 on the advertised .476 for the cam).  These will work with the manual/mechanical lash adjuster valves, and at least a .080 lash cap (with a short skirt).  The cap just starts to preload the lifter, but we are sure they will come out unless a sure fire way to secure them to the valve is used.  Is there one? Other than a screw in cap on a prepped valve, there really isn't. There may be an epoxy that is rated hi-heat enough, but we hate to rely on such things, and don't recommend doing it. TEP offers a .125" lash cap, but they are shelf stock not to be replaced when they run out, and Steve said they send whatever size caps with their custom length valves since some final grinding is usually needed, and a little difference in cap size should never be a problem.

Well, I'm getting tired, and broke from this stuff, and am just going with my TEP custom length valves, and .080 lash caps.  We are preloading the lifter a little (.050at least), by cutting the seats on my brand new Marnal head. Yes, cutting brand new seats.  Actually, we chose to cut them for performance reasons, and it will help put more pre-load on the lifters.  The seats come stock with wide cut angles for increased longevity.  Cutting them a little narrower works with more precision, and flows much better. It should still last as long as stock if the fuel mix stays good throughout its life.  The wider angles just give better insurance for life, but decrease flow performance somewhat. We are also doing the pocket porting above the valve, but the Marnals have bigger pockets than the factory, and we won't have to cut nearly as much into it for that.  Pocket porting is something that started in the Stock classes of racing where runner porting is not allowed.  They found that opening up the pockets got them better increases anyway, and that is allowed in stock racing classes. FYI: The Marnals have the same runner flow as stock, but have better cooling passages, and manifold stud mounting bosses. Otherwise, they are the same (except the slightly bigger pockets, but that could be a year difference, and we just compared it to the '86 Caravan head I had).

Tim C.

[Tim_C.]

Well, we have pretty much given up on the idea of offering the Schneider 284RH as a bolt on cam, because it just can't be bolted on.  Using the 3.0L rockers will hit the pistons on any application. Mine hit with .510 lift. Those are .544. No way any head will work with that unless you lower the CR ratio by using a thick copper head gasket. No one wants to do that.

I have the pictures of Hendu's set up.  There are NO lash caps!  So kev says the numbers match his 3.0 rocker, so I believe that to be true, but there is no way to use the 284RH cam with stock length valves, and no caps.  By looking at the picture of Hendu's set-up, there is no way that is th 284RH in there.  Jerry at Schneider told me that all of the 284RH's are reduced base circle, and all of them the same reduction. The only rocker in Hendu's picture that you can see the lifter end, and the cam base cirlce, clearly shows the larger base circle.  That is NOT a 284RH cam! Its most likely a 284 standard tappet cam.  Show me a roller lobe on that cam, & I'll believe it then, but it is not possible to hide a roller lobe on that size base circle.  You would see those monster lobes showing their guns in that picture.  They are just not there.  I'm not saying Hendu is not telling the truth about his application, but just saying maybe he was told it was a roller lobe cam, but it is not.  Those rockers would be all steeped in that pic.  They are not. Why? Becasue a slip rocker 284 cam only has 435 lift, and the tip of the lobes are narrow because it can't hold the valve open as long as a faster acting roller lobe.  That is a slip rocker 284 at best.

Is that a decent set-up? Yes, and that's why TEP and all suppliers don't offer the Roller Cams.  You get .496 lift with the slip rocker cam, and to go roller, you need to flycut the pistons, increase the valve length, & raise the valve cover. This requires a complete engine teardown to accomplish. Can we grind a roller cam with just enough more base circle to work, and less initial cam lift to not hit pistons? You bet!  But we will not be using the Schneider Cams. We are getting our own grind together & having our company grind them. They grind for 2.6 racers all over the world, so we are confident it will work. The Aussies use a 1.3 ratio rocker. That doesn't make sense, because then you need even bigger roller lobes on the big base circle. Our idea will fit under the cover, so we will get it together, and hopefully offer it by the end of Summer.

Tim C.

[kev]

Well hendu just said that he called up Jerry and said he wanted a 284 cam ground for use of roller rockers.   He never checked from there.  He just tossed it in with the 3.0 rockers and drove.  Nope he doesn't have lash caps.   So yes it is possible that Jerry sent him a regular cam.

 

kev

[kev]

Here is the pic of hendu's head just so others could see.   yes I think I agree with you Tim, the one lobe that you can see looks way to fat compared to my 284rh cam.

 

 

http://www.f150online.com/galleries/images/137-134-14947.jpg

[Tim_C.]

Yep, that's what Jerry sends if someone wants to use roller rockers on his cams. Especially when worded as such because Jerry knows it requires much more than slapping the rockers on to run the roller cam.  He won't mention that when you order a roller cam either.  I had to bring it up, and he stayed as vague with his answer as possible. Like, "we don't know exactly what it takes to run it, but there are many people doing it." He just tells you it needs dual coil springs, and not just HD.

Tim C.

[kev]

He gave me the same line!   He reminded me of James actually.  

 

kev

[Tim_C.]

Yep, I think James CNM got his BS technique from Jerry! He He! No, I just see Jerry wanting to make a sale, and he chooses what to say by how you present what you need to him. If you specify roller cam, he figures you will have a machinist set you up, and he doesn't mention all the details involved, and I'm sure he really doesn't know all of them.  He lets everyone else figure that out.

For me, that took a tune of $600+, and a few months of research in the school of hard knocks!!

Tim C.