Converting stock M52 lifters from hydraulic to solid

[someguy2800]

Thought I would share this on here. This is the solid lifter conversion system that I made and am testing in my car. The system uses hardened steel selective shims that go inside the stock lifters to set the lash.

[pbonsalb]

At what rpm do the hydraulic lifters in these motors cause problems? Or do the problems result more from certain cam profiles?

If rpm is the determining factor, how are the S65 hydraulic lifters designed differently to allow 8600 rpm without issue? Or is it the engine oiling system that is designed differently?

[ross1]

Thought I would share this on here. This is the solid lifter conversion system that I made and am testing in my car. The system uses hardened steel selective shims that go inside the stock lifters to set the lash.

Cams out for adjustment then? Good Lord, thinking of the lash adjustment gives me the shivers. Way worse than typical shim and bucket.
My hat's off to you, pal. Hope it pays off.

[NOTORIOUS VR]

At what rpm do the hydraulic lifters in these motors cause problems? Or do the problems result more from certain cam profiles?

All of the above, including the ability to maintain solid oil pressure in the head (which is not always obvious there is an issue when measuring elsewhere on the block), the size/weight of the valvetrain parts, etc.

If you're spending a lot of time revving out well past std. rev limit - and there is an issue with the hydraulics keeping up you will see wear on the cam/followers.

[jakermac]

Is it not true that solid lifter cam profiles are different than hydraulic cam profiles?

[PEI330Ci]

16 Lifters on each side? What engine are you running?

One observation I have about this conversion is that the oil is still going to be pushing on the lifter plungers. The static height of the lifter will be fixed when the engine is off, but then oil pressure with the engine on will push the lifter into the face of the cam lobe. So in effect, you have created a variable height hydraulic lifter which goes between zero clearance, and a compressed height absorbing the shock of the lift ramp.

With normal solid lifters, the static height of the lifter remains constant regardless of the oil pressure. With the engine running, there is nothing pushing the face of the lifter into the cam lobe's base circle.

The other thing is that the weight of the lifter body will be substantially heavier than a true solid lifter body, especially when oil volume is added into the back-side of the lash cap cavity.

I have both brand new OEM BMW 33mm lifters, and a complete set of solid motorsport lifters from Schrick that I can compare the weights of when I get back home if you like? I'm planning on spinning my engine fairly high....so this topic interests me greatly.

[someguy2800]

At what rpm do the hydraulic lifters in these motors cause problems? Or do the problems result more from certain cam profiles?

If rpm is the determining factor, how are the S65 hydraulic lifters designed differently to allow 8600 rpm without issue? Or is it the engine oiling system that is designed differently?

It depends on how aggressive the cam profile is. I have been revving to 8500 for a long long time on hydraulic lifters with no ill effects that I could really see, but I have also always been running super mild cams. With more aggressive profiles people start having problems around 7500-8000, and I have heard some people getting lifter noise on decel with some of the more aggressive cams even at 7200. I don't know anything about S65's

- - - Updated - - -

Cams out for adjustment then? Good Lord, thinking of the lash adjustment gives me the shivers. Way worse than typical shim and bucket.
My hat's off to you, pal. Hope it pays off.

Yes, cams have to come out to adjust. Unfortunately there is no other way in an M50.

- - - Updated - - -

Is it not true that solid lifter cam profiles are different than hydraulic cam profiles?

Yes the opening and closing ramps are different. You can run a solid lifter on a hydraulic profile cam however, you just need to run a relatively tight lash, say .004-.005" intake, and .006-.007" exhaust, and will need to be adjusted more often. A typical solid lifter cam cam be run at .010-.012" lash because they have a longer ramp.

[someguy2800]

16 Lifters on each side? What engine are you running?

One observation I have about this conversion is that the oil is still going to be pushing on the lifter plungers. The static height of the lifter will be fixed when the engine is off, but then oil pressure with the engine on will push the lifter into the face of the cam lobe. So in effect, you have created a variable height hydraulic lifter which goes between zero clearance, and a compressed height absorbing the shock of the lift ramp.

With normal solid lifters, the static height of the lifter remains constant regardless of the oil pressure. With the engine running, there is nothing pushing the face of the lifter into the cam lobe's base circle.

The other thing is that the weight of the lifter body will be substantially heavier than a true solid lifter body, especially when oil volume is added into the back-side of the lash cap cavity.

I have both brand new OEM BMW 33mm lifters, and a complete set of solid motorsport lifters from Schrick that I can compare the weights of when I get back home if you like? I'm planning on spinning my engine fairly high....so this topic interests me greatly.

Yeah someone else caught the 16 lifters lol. Yes you are correct the oil pressure will still be flowing into the lifter, it just won't be held in because of no check valve. The reason I chose to do this with the M52 lifters is because they are the lightest of the stock lifters and have the smallest plunger so they will have the least amount of hydraulic pressure. M52 lifter full of oil weighs 47 grams. The advantage to this over completely new solid lifters is of course cost, and also eliminating the lash caps. This will cost about 1/6th as much as a typical solid lifter conversion and because the shims are contained inside the lifter plunger there is no possibility that anything can fall out of place. A friend of mine recently lost an M52 due to a dropped valve after one of their lash caps fell out of place.

[someguy2800]

Just as a point of comparison on the weight, the factory shim over bucket lifters in a 2JZ weigh 45 grams each. The aftermarket shimless buckets are about 30. I'm curious what your shrick solid lifters weigh

[Randy Forbes]

Yes, cams have to come out to adjust. Unfortunately there is no other way in an M50.

Slightly OT, but while we're on the subject...

What method do you employ when removing the cams? Way back when (2002?) I bought ALL the BMW S54-specific engine tools I expected I'd ever need, the cam-press being one of them. While the spacing is off for the S52s I've done, it still works (backburner project is to machine saddles to fit each engine...).

Just curious to know how you're doing them, and it sounds like you're now doing it even more often, so I figure you* have a streamlined process.



* there are few contributors that I trust 100% of what they post (not limited to the FI section) but I've never found you to deal out a bad hand.

[someguy2800]

Slightly OT, but while we're on the subject...

What method do you employ when removing the cams? Way back when (2002?) I bought ALL the BMW S54-specific engine tools I expected I'd ever need, the cam-press being one of them. While the spacing is off for the S52s I've done, it still works (backburner project is to machine saddles to fit each engine...).

Just curious to know how you're doing them, and it sounds like you're now doing it even more often, so I figure you* have a streamlined process.



* there are few contributors that I trust 100% of what they post (not limited to the FI section) but I've never found you to deal out a bad hand.

If you look at the cam while its in the engine there are only ever two pairs of cam lobes that are actually pointed down and pushing on the lifters. I take off all the caps except for the two that are on those lobes, and then I just slowly take off those two caps like one turn at a time. I do the same in reverse to install them.

[Randy Forbes]

If you look at the cam while its in the engine there are only ever two pairs of cam lobes that are actually pointed down and pushing on the lifters. I take off all the caps except for the two that are on those lobes, and then I just slowly take off those two caps like one turn at a time. I do the same in reverse to install them.

Okay, I've done that in a pinch too. There's just not too many options.

Thanks!

[PEI330Ci]

Yeah someone else caught the 16 lifters lol. Yes you are correct the oil pressure will still be flowing into the lifter, it just won't be held in because of no check valve. The reason I chose to do this with the M52 lifters is because they are the lightest of the stock lifters and have the smallest plunger so they will have the least amount of hydraulic pressure. M52 lifter full of oil weighs 47 grams. The advantage to this over completely new solid lifters is of course cost, and also eliminating the lash caps. This will cost about 1/6th as much as a typical solid lifter conversion and because the shims are contained inside the lifter plunger there is no possibility that anything can fall out of place. A friend of mine recently lost an M52 due to a dropped valve after one of their lash caps fell out of place.

I've had a set of solid lifters on the shelf since 2009. The plan was to use them with a set of custom Schrick cams, (300/296) but I never got around to using the cams, and ended up selling them to a touring car team. So I've still got the lifters....and have been hesitant to sell them knowing very few people will pay the $50 a piece that I did. (And there are 24 of them!) The catch to this is that I don't have any lash caps.....it was something I was was waiting to install the cams to order.

I'm planning to install the brand new stock OEM lifters with the 272/256 cams I currently have, and will rev the engine to probably around 8,000 RPM. I ran "old" stock lifters with the last engine up to 7600 RPM no problem, so I figured another 8000 RPM wouldn't hurt. (New short runner intake manifold will probably move the power band up a bit)

[someguy2800]

I've had a set of solid lifters on the shelf since 2009. The plan was to use them with a set of custom Schrick cams, (300/296) but I never got around to using the cams, and ended up selling them to a touring car team. So I've still got the lifters....and have been hesitant to sell them knowing very few people will pay the $50 a piece that I did. (And there are 24 of them!) The catch to this is that I don't have any lash caps.....it was something I was was waiting to install the cams to order.

I'm planning to install the brand new stock OEM lifters with the 272/256 cams I currently have, and will rev the engine to probably around 8,000 RPM. I ran "old" stock lifters with the last engine up to 7600 RPM no problem, so I figured another 8000 RPM wouldn't hurt. (New short runner intake manifold will probably move the power band up a bit)

The hydraulic lifters do okay with good spring pressures as long as the ramp rates on the cams arn't too extreme. You probably will be fine to 8000. I am changing up my program a bit to try to make more power and extend the rpm range. Enem in sweden is making me a set of custom 276/276 solid lifter cams and I have a billet short runner intake manifold going on. I am hoping to move peak power up to 8500-9000 rpms and probably have a 9500 rpm rev limit.

[Johnbennett103]

I am building a twin turbo M60B30, and I also did a solid cam conversion. I first ground the solid lifters down a bit, and then I used a micrometer and shims to get to the final setting. It was tedious at first, but then I picked up steam. I hope to start up my engine in the next month.

[PEI330Ci]

The hydraulic lifters do okay with good spring pressures as long as the ramp rates on the cams arn't too extreme. You probably will be fine to 8000. I am changing up my program a bit to try to make more power and extend the rpm range. Enem in sweden is making me a set of custom 276/276 solid lifter cams and I have a billet short runner intake manifold going on. I am hoping to move peak power up to 8500-9000 rpms and probably have a 9500 rpm rev limit.

One thing that catches a lot of people off-guard when doing this is the accessory drive speeds. Steering pumps and alternators aren't designed for 50% more operating speed....so there usually is some kind of reduction in the pulley system required. I know of a few race teams that move to electric power steering systems to avoid the issue. For the alternator, that's where these tiny Bosch Motorsport pieces get put in....as they have a different operating range than an OEM component. I've already blown up one stock alternator with increased operating speeds.......now I'm planning on putting a larger pulley on my current "stock" alternator to reduce the load at higher RPMs. (I can deal with the loss of charge rate at idle)

I'm on the fence about an EPAS system for my steering....not sure if I want the cost/headache of adding another component to my "project" plan.

[someguy2800]

I don’t run power steering but I was concerned about the water pump cavitating from spinning too fast.

[pbonsalb]

I recall speaking to a Stewart rep years ago who said the stock style WP cavitates at high rpm, but the Stewart pump does not. Obviously self serving info but may be accurate. Not sure what rpm but assume that was within a normal stock or modded limit of 7200.

As I recall there is not much space for a large underdrive pulley. Obviously there are slight UD pulleys available. Maybe a Stewart pump plus one of those would delay the need to go electric.

[someguy2800]

Yeah I have been thinking about getting the stewart warner pump and maybe machining a larger alternator pulley because I have read that they say the same thing and I see some evidence of it in my datalogs. Typically drag racing I start the run at like 180 degree coolant temp and when I go through the traps it will have only climbed like 2 or 3 degrees, or sometimes even go down a bit. Then after I go through the traps and the RPMs start coming down it will climb up to like 190 degrees. So I think the coolant is not actually circulating during the run up at 7000-8500 rpms, but then when it slows down it starts pumping the heat up into the head to the sensor. I think I have enough alcohol going into the motor though that this isn't really a problem. Unless the temps actually get out of control or it starts killing water pumps or alternators I'm not going to worry to much about it. I did kill one alternator last year after beating on it all day at powercruise doing roll races.

[PEI330Ci]

Yeah I have been thinking about getting the stewart warner pump and maybe machining a larger alternator pulley because I have read that they say the same thing and I see some evidence of it in my datalogs. Typically drag racing I start the run at like 180 degree coolant temp and when I go through the traps it will have only climbed like 2 or 3 degrees, or sometimes even go down a bit. Then after I go through the traps and the RPMs start coming down it will climb up to like 190 degrees. So I think the coolant is not actually circulating during the run up at 7000-8500 rpms, but then when it slows down it starts pumping the heat up into the head to the sensor. I think I have enough alcohol going into the motor though that this isn't really a problem. Unless the temps actually get out of control or it starts killing water pumps or alternators I'm not going to worry to much about it. I did kill one alternator last year after beating on it all day at powercruise doing roll races.

This is where running an inline propeller type water pump can be useful. I'm planning on running one of these in series with the Stewart belt driven pump in the stock location:

https://www.stewartcomponents.com/in...&product_id=69

The trick to this is turning it on when you know the thermostat valve is open.....otherwise....no flow. (Unless you are using it to help feed turbo cooling and wastegate cooling)

I ran one of these on the black car, and it worked really well.

[chikinhed]

I recall speaking to a Stewart rep years ago who said the stock style WP cavitates at high rpm, but the Stewart pump does not. Obviously self serving info but may be accurate. Not sure what rpm but assume that was within a normal stock or modded limit of 7200.

As I recall there is not much space for a large underdrive pulley. Obviously there are slight UD pulleys available. Maybe a Stewart pump plus one of those would delay the need to go electric.

I removed a Stewart WP that had lots of cavitation damage. I don’t rev beyond 7200 rpm.

[pbonsalb]

A few people have said they had issues with their Stewart pumps. Mine is 12 or 13 years old and has been in 3 motors, but has only about 70k miles on it.

[XnWarden]

You guys are mad scientist gurus when it comes to these cars. Makes me feel like a caveman beating at my chassis with a club. Good stuff. Thanks for a wealth of knowledge

Sent from my SM-G975U using Tapatalk

[budgetbmw3]

Are there no other applications that have the same pulley mount dimensions that would lower the RPM of the accessories? Potentially some of the M model or other foreign cars who use the same OEM suppliers? Not sure how easy it would be to find that information.

[E36 HateR]

Did this conversion on my engine today, took my time, the trick was stacking enough shims to get an accurate measurement the first time, perrys lifter magnets work great for this too.

Hopefully this fixes my issue ive been having with my engines murdering valves.