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r_towle |
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#61
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
I was more interested in the fact that there is no signed of any alignment, or rotational control on the lifters.
Not sure if I am explaining what I mean properly, but I noticed your setup holds the lifter in the bore so the lifter cannot rotate in any direction, while these look like there is nothing designed to do that, and yet the motor did survive and the camshaft did not look totally spent. Agree on some of the other issues with the motor, not interested in those point....just what you find when you open up these motors... The lifters, why would they twist and what force is making them twist in the bore, if that is what you are saying.... |
HAM Inc |
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#62
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Senior Member ![]() ![]() ![]() Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None ![]() |
Those are .742 Harley lifters. The wheel diameter is so great that you must have a very large base circle camshaft. These hate lash, the issue that I had with them came mostly from axles failing prematurely do to base circle, and lash. The closest I came to success with these was using a Schubeck RollerX lifter that has no axle, but those went away with Schubeck in 2007. If the base circle is too small, these things run super loud, sounds like a diesel. They beat themselves to death. Again, you will have to rework the case to realign the cam tunnel with the lifter bores. These are no where near perpendicular enough for a roller cam to live without cam walk in any T4 case I have seen yet. That includes brand new, NOS cases. Call a company named BHJ, for about 6k they will make some jigs to your design to facilitate this, but when it doesn't work, and you chop up what they made to make it right, you'll be mad enough to spit nails. You must "nest" the lifter with this arrangement, else the first rotation of the cam, every lifter will turn 90 degrees and crash the cam. We even tried to change the cam lobe to retain the proper lifter orientation, but those oil samples had 12X more iron in them than the worst comparative sample, and visual wear was very clear. Modern Porsche engines have nested tappets, to allow for variocam plus on the intake, and VVT on the exhaust. In these engines a dowel is employed to do the job of alignment, but the cam profile is kept very conservative. It's no where near the lift per crank degree that the mildest roller profile that you'll find (Fox body Mustang, stock profile). Don't put too much stock in what the guy in those pics has done... It's clear that he hasn't been able to achieve a proper cylinder head to cylinder seal, which is the first essential to T4 performance. See that nasty head surface? Yep, he had a head leak. Holy head-leak Batman! Those registers have been opened for big bore jugs, which I'd bet plenty of $$ were iron. Leaks in general, and that area in particular, are a classic symptom of big iron jugs, which just don't stay sealed long on T4 engines. I have seen that soooo many times over the years I can spot it from across the room. |
Randal |
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#63
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 4,446 Joined: 29-May 03 From: Los Altos, CA Member No.: 750 ![]() |
I think only available in his fully built motors...so us "normal" folk will never have the chance to purchase them (IMG:style_emoticons/default/smile.gif) Pauter sells them, but I have the feeling only all out race motors (and type 1 instead?) Being that a new solid camshaft kit is $1000 from the TypeIV store, I would venture to say that the roller setup would be minimum 2X that price. 222 has them in the 2.4 liter motor. They work great and are still working great if you look at the GGR AutoX results. |
Bills914-4 |
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#64
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Member ![]() ![]() Group: Members Posts: 310 Joined: 1-March 08 From: suburbs of Miami FL. Member No.: 8,762 Region Association: South East States ![]() |
Maybe I'm not seeing something but those roller lifters don't have the oil groove around
the body (to allow the oil up thru the push rods to rockers) and they don't look like they have any wear marks on the body dia. , maybe I'm wrong & this is not finished being set up (IMG:style_emoticons/default/confused24.gif) , plus they will need some form of locking the rotation . |
r_towle |
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#65
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
Maybe I'm not seeing something but those roller lifters don't have the oil groove around the body (to allow the oil up thru the push rods to rockers) and they don't look like they have any wear marks on the body dia. , maybe I'm wrong & this is not finished being set up (IMG:style_emoticons/default/confused24.gif) , plus they will need some form of locking the rotation . That is the part I don't believe is required, locking the rotation. What force would make them twist if they are in constant contact with the camshaft. If they are touching all the time they would be forced to stay square. For oil, it's possible there is a hole in the middle, not sure, no other pics. |
scott_in_nh |
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#66
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Senior Member ![]() ![]() ![]() Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States ![]() |
Maybe I'm not seeing something but those roller lifters don't have the oil groove around the body (to allow the oil up thru the push rods to rockers) and they don't look like they have any wear marks on the body dia. , maybe I'm wrong & this is not finished being set up (IMG:style_emoticons/default/confused24.gif) , plus they will need some form of locking the rotation . That is the part I don't believe is required, locking the rotation. What force would make them twist if they are in constant contact with the camshaft. If they are touching all the time they would be forced to stay square. For oil, it's possible there is a hole in the middle, not sure, no other pics. Rich my Buell has a sportster based motor with roller lifters/cams. It uses pins to keep the lifters inline and one of them failed. The lifter turned sideways, ground away on the cam and wheel and when it got hot enough to seize the lifter, the piston hit and bent the exhaust valve. You would need caster to have them point the right way by themselves. |
Elliot Cannon |
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#67
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Retired Members Posts: 8,487 Joined: 29-December 06 From: Paso Robles Ca. (Central coast) Member No.: 7,407 Region Association: None ![]() ![]() ![]() |
where do you (did you) get Ceramic lifters? Mine were for sale on the "Samba" about 12 years ago. $500. (Thanks Clayton, wherever you are). I don't think they are available any longer. I figure I have $1000 worth of valve lifters in my engine. (IMG:style_emoticons/default/laugh.gif) |
Dave_Darling |
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#68
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914 Idiot ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California ![]() ![]() |
What force would make them twist if they are in constant contact with the camshaft. If they are touching all the time they would be forced to stay square. Well, if there is valve lash, that can propagate all the way to the lifter, so there won't necessarily always be contact. And if there is any tendency at all for the lifter to turn at all, there doesn't seem to be a way that it will correct itself, so it will just get worse and worse until it gets to 90 degrees and turns into a lathe bit. Remember that the stock lifters are designed specifically to rotate, in order to spread the wear out. I think there is a slight built-in taper to the cam lobes that helps with this, and the lifter bores are offset from the cam axis as well. If you get the alignment perfect, and spec a cam with zero taper, you might be able to convince the lifter not to rotate. But unless you have a way to correct any rotation that may occur, eventually you're going to get one flipped 90 degrees and you'll be super unhappy. --DD |
Jake Raby |
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#69
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
The mechanical tendency of the lifter is to rotate as it travels up the opening ramp of the cam lobe. I found that this tendency occurs at roughly .175" lobe lift with most profiles. It's much easier for the lifter to try to turn, than for it to ascend up the ramp, the more lift it sees, the more valve spring load it sees, and the quicker the issue at hand becomes apparent.
None of the photos that you have seen are of my final lifter/ indexing design. In fact, it's a far departure from those designs, in every way. I abandoned that, and sold the lifters, and tooling on thesamba. The lifter is now indexed with two control surfaces, sharing noting in common with previous attempts. If one believes that a roller lifter can self index, and maintain alignment with the cam lobe with no mechanical limitation, they haven't studied the fundamentals of roller lifter and cam evolution. The challenge that everyone has had stems from this same issue. Some use dowels, some use links between lifters, and others use tunneled bushings. All of these have caveats. If you just throw a roller lifter in the mix, and expect it to follow the cam lobe, you'll be disappointed before the engine is even assembled. The lifters will roll sideways and crash the lobes before you get all the valves adjusted on the bench. Once you get the roller mechanicals figured out, then you'll need to pony up for custom springs, retainers, and valves, so you can net dramatically increased spring pressures that will allow for more lift, while handling the insane opening and closing speeds of the roller actuated lifter, and pushrod. Once you tackle that, then you'll learn that the pushrods that are readily available are deflecting under load, and costing you valve timing. You won't notice this at first, but maybe after 3 months of beating your head against the wall you'll remember this post. If someone has head leaks that bad, less time needs to be spent on the crazy stuff, and more on the elementary level elements of T4 modification. There's a possibility that the engine had a tendency for head leaks due to the cam profile that was used, as it's easy to build too much dynamic CR and cylinder pressure with a roller arrangement. Been there. The dynamics associated with utilizing a roller lifter impact the entire engine combo. Don't be one of those guys that says "I'll not worry about any of that, because I'll keep it mild". Guess what? You'll hit all the same issues as the engine I have running .700" valve lift. The last set of ceramic lifters I sold went for 2k, I have one more set that I'd take that amount for, the other 10 sets I'll be selfish and keep for my own cars. This post has been edited by Jake Raby: Oct 31 2015, 09:30 PM |
rhodyguy |
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#70
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Chimp Sanctuary NW. Check it out. ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 22,098 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch ![]() |
No mr 914werke, you have no idea what you're talking about, nor my assertions or their validity. The validity of my comments is well documented here, the old shoptalk forums and other sites as well. Events that occurred LONG before you became a member. I suggest you go back to posts starting in the spring of 2005 and sift thru them to find the information. Then you can avoid looking like an uniformed fool in the future. Pretty sure you've used 'analogy' in the wrong context too. Nice try but you've missed the mark. I will give you a 'pass' this time but not in the future. Rookie.....
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r_towle |
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#71
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
The mechanical tendency of the lifter is to rotate as it travels up the opening ramp of the cam lobe. I found that this tendency occurs at roughly .175" lobe lift with most profiles. It's much easier for the lifter to try to turn, than for it to ascend up the ramp, the more lift it sees, the more valve spring load it sees, and the quicker the issue at hand becomes apparent. None of the photos that you have seen are of my final lifter/ indexing design. In fact, it's a far departure from those designs, in every way. I abandoned that, and sold the lifters, and tooling on thesamba. The lifter is now indexed with two control surfaces, sharing noting in common with previous attempts. If one believes that a roller lifter can self index, and maintain alignment with the cam lobe with no mechanical limitation, they haven't studied the fundamentals of roller lifter and cam evolution. The challenge that everyone has had stems from this same issue. Some use dowels, some use links between lifters, and others use tunneled bushings. All of these have caveats. If you just throw a roller lifter in the mix, and expect it to follow the cam lobe, you'll be disappointed before the engine is even assembled. The lifters will roll sideways and crash the lobes before you get all the valves adjusted on the bench. Once you get the roller mechanicals figured out, then you'll need to pony up for custom springs, retainers, and valves, so you can net dramatically increased spring pressures that will allow for more lift, while handling the insane opening and closing speeds of the roller actuated lifter, and pushrod. Once you tackle that, then you'll learn that the pushrods that are readily available are deflecting under load, and costing you valve timing. You won't notice this at first, but maybe after 3 months of beating your head against the wall you'll remember this post. If someone has head leaks that bad, less time needs to be spent on the crazy stuff, and more on the elementary level elements of T4 modification. There's a possibility that the engine had a tendency for head leaks due to the cam profile that was used, as it's easy to build too much dynamic CR and cylinder pressure with a roller arrangement. Been there. The dynamics associated with utilizing a roller lifter impact the entire engine combo. Don't be one of those guys that says "I'll not worry about any of that, because I'll keep it mild". Guess what? You'll hit all the same issues as the engine I have running .700" valve lift. The last set of ceramic lifters I sold went for 2k, I have one more set that I'd take that amount for, the other 10 sets I'll be selfish and keep for my own cars. As always, you raise an interesting set of related factors. I believe you when you say they turn. I can't visualize it at the moment, but I will see it over the winter when I go to replace the camshaft.... Most likely won't go down this road unless I can achieve my goals. After all is said and done, what is the benefit of going this way from a torque perspective? Ideally, having better tolerances, and less adjustment maintenance would be my personal goal. |
DBCooper |
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#72
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
After all is said and done, what is the benefit of going this way from a torque perspective? Ideally, having better tolerances, and less adjustment maintenance would be my personal goal. With a roller you can have steeper ramps on the lobes to open and close the valve faster. Means you can get the cam profile closer to what you want rather than what's possible. You've got an aircooled engine, though, so unless they're hydraulic lifters you're still going to be adjusting valves in the same intervals. |
Mark Henry |
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#73
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
I have a set of ceramics sitting on the shelf (IMG:style_emoticons/default/happy11.gif)
And a set in my 1967 bug. |
Mueller |
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#74
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914 Freak! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None ![]() ![]() |
Maybe it's just me, but I want my next Type IV to have more than one cam to open the valves (IMG:style_emoticons/default/wink.gif)
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r_towle |
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#75
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
Maybe it's just me, but I want my next Type IV to have more than one cam to open the valves (IMG:style_emoticons/default/wink.gif) Stop it, my head hurts. Where are those pics of the guys that were working on that? They even had a website for a while, then the project went quiet. Rich |
stugray |
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#76
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None ![]() |
Maybe it's just me, but I want my next Type IV to have more than one cam to open the valves (IMG:style_emoticons/default/wink.gif) Stop it, my head hurts. Where are those pics of the guys that were working on that? They even had a website for a while, then the project went quiet. Rich It's called overhead cams. If you had your own machine shop and money & time to burn, you could probably convert some 911 heads to fit on a type IV, then make some custom cams.... If you want to talk about radical modifications, then consider my idea where I use a 6 cyl boxer engine and use the two middle cylinders as a supercharger. Put the largest avail. jugs on the middle two, and the smallest jugs avail on the outer 4, custom heads and bingo - internally supercharged 2.0L 4 cyl. All it would take is an infinite amount of time & $$ :-) Noodle on that for a bit Sorry for the OT |
Mueller |
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#77
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914 Freak! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None ![]() ![]() |
Sorry...more OT...dual Ducati converted to single using other cylinder for a supercharger
http://thekneeslider.com/ducati-v-one-twin...gle-conversion/ |
DBCooper |
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#78
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
I don't understand why you wouldn't just add a super or turbocharger to the engine you have.
Bottom line on all those projects is that at the end of the day it's still gonna be air cooled, with all the limitations that are built into that. Means it ends up being a pretty small box to think inside of. |
r_towle |
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#79
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
I don't understand why you wouldn't just add a super or turbocharger to the engine you have. Bottom line on all those projects is that at the end of the day it's still gonna be air cooled, with all the limitations that are built into that. Means it ends up being a pretty small box to think inside of. I think you are coming at this way to binary. It's not an either or question. I can have fun with both air cooled and water cooled....no need to limit the fun. Having grown up rebuilding VW motors for years, it's fun to see if there is any more to find....Jake admitted that 200 was it, now he is at 300hp. Supercharger, turbo, overhead camshafts, it can all be fun with both water cooled and aircooled. For me, most of the fun the the project, it's cheaper than therapy. |
DBCooper |
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#80
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14's in the 13's with ATTITUDE ![]() ![]() ![]() ![]() Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California ![]() |
Sure, but it's a quest of diminishing returns, where to get Jake's horsepower will cost you $25,000. Worse, for you to get near that yourself, with all the dead ends that you'll inevitably have to negotiate, your cost will be a multiple many times that.
That's not cheap therapy in my neighborhood, Rich. I enjoy puzzles and building engines, but more when I was younger than now. For me now the best therapy is going for a fast drive through the mountains, then having a nice lunch up in the hills somewhere and not worrying too much about it. But obviously I understand, it's the quest and everyone does that differently. |
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