Ross Performance Harmonic Balancer

[enjoy_m3]

Stan,

I personally have a better idea of how to make the S54 rev to 8500rpm on daily basis with
Warranty, but its not via upgraded custom damper !!!

Regards,
Anri.

So what's the secret sauce? lol

[Anri]

So what's the secret sauce? lol

Hi,

The secret sauce is increasing the crankshaft rigidity.
Stock damper will remain in place.

There are few things I can alter to increase strength. Its
a package of several changes must be made in order to
improve over std crankshaft.

In other words the crank twist will still exist but I will
be able to move the dangerous frequency starting at 9000rpm+
So the mathematical equation shows that at around 8800rpm
it will be strong as std crankshaft at say 7950rpm.
I have been looking over this for long time and after my
S38 project may be I will put something together...if there is
any interest..

These changes will work very well with increased stroke.
Our cars are heavy and the power curve is much better
to start early with very hi HP under the curve. Asking hi HP
from the std engine is knife with 2 sharp edges..Adding
more cam x rpm and the engine will start coming in cam
later on the revs..Vanos helps tremendously! to make the
S54 move. I always laugh at those who want to delete the
Vanos with the std manual transmission.

In my book goes as follow. Road going cars with full interior
AC, larger wheels, wider tires, say light weight seat etc this
set up I favor stroker choice with 8000rpm are plenty enough.

Race engine needs rev for the track, I will remain on std stroke
at 91mm but with the trick changes and it will rev to 8700-8800rpm
no problem.


Regards
Anri

[stash1]

Right - the ATI damper may or may not be properly engineered for its intended purpose, but it will be hard for us as a community to determine if that's the case by trial and error because nobody can keep a damn belt on the VAC pulley to begin with lol. Maybe next season I'll get a Ross Performance part and see if it at least actually fits right.

Ya, I heard that they're spitting belts..the damper itself may be fine? If you end up getting one, or find any additional info, plz feel free to post up!

[stash1]

Hi,

The secret source is increasing the crankshaft rigidity.
Stock damper will remain in place.

There are few things I can alter to increase strength. Its
a package of several changes must be made in order to
improve over std crankshaft.

In other words the crank twist will still exist but I will
be able to move the dangerous frequency starting at 9000rpm+
So the mathematical equation shows that at around 8800rpm
it will be strong as std crankshaft at say 7950rpm.
I have been looking over this for long time and after my
S38 project may be I will put something together...if there is
any interest..

These changes will work very well with increased stroke.
Our cars are heavy and the power curve is much better
to start early with very hi HP under the curve. Asking hi HP
from the std engine is knife with 2 sharp edges..Adding
more cam x rpm and the engine will start coming in cam
later on the revs..Vanos helps tremendously! to make the
S54. I always laugh at those who want to delete the Vanos
with the std manual transmission.

In my book goes as follow. Road going cars with full interior
AC, larger wheels, wider tires, say light weight seat etc this
set up I favor stroker choice with 8000rpm are plenty enough.

Race engine needs rev for the track, I will remain on std stroke
at 91mm but with the trick changes and it will rev to 8700-8800rpm
no problem.


Regards
Anri

Girdle?

[CrookedCommie]

Ya, I heard that they're spitting belts..the damper itself may be fine? If you end up getting one, or find any additional info, plz feel free to post up!

I've got one for sale if you guys want to give it a shot.

https://nam3forum.com/forums/forum/classifieds/members-parts-for-sale-wtb/e46/193590-zf-4-clutch-lsd-vac-ati-damper-clutchmasters-slave-cylinder

[Anri]

Girdle?

No

[stash1]

No

Ahhh, I just re-read your post...you're not suggesting physical changes, but cam timing/tuning changes.

[Anri]

Ahhh, I just re-read your post...you're not suggesting physical changes, but cam timing/tuning changes.

Brother, no no no, Concentrate.

I am talking about making a new crankshaft with
DNA change !!! the internals will be also diff
configuration !!!!

Any crankshaft will fail no matter what.

The trick is to push the dangerous frequency above
the intended use of RPM say a safe range is 8000rpm
but at 10.000rpm the crankshaft Second order or 3rd
or 4th harmonics will destroy the crankshaft in 5 pieces
but you are not planing to push to 10.000rpm.

Stroke is the King for street use like your toy also track
but revs will remain at 8000rpm not 1-rpm over !

Regards
Anri

[stash1]

Brother, no no no, Concentrate.

I am talking about making a new crankshaft with
DNA change !!! the internals will be also diff
configuration !!!!

Any crankshaft will fail no matter what.

The trick is to push the dangerous frequency above
the intended use of RPM say a safe range is 8000rpm
but at 10.000rpm the crankshaft Second order or 3rd
or 4th harmonics will destroy the crankshaft in 5 pieces
but you are not planing to push to 10.000rpm.

Stroke is the King for street use like your toy also track
but revs will remain at 8000rpm not 1-rpm over !

Regards
Anri

Ahhh, sorry brother, not poking fun…but your words/sentences are just a bit difficult to follow sometimes-lol. It seemed that you were suggesting altering cam timing or something to reduce stress on the bottom end…guess I was the only one to see it that way.

Sooo, you’re saying that the factory balancer can’t be improved upon because BMW engineers spent thousands of hrs developing/testing, but the factory crankshaft (that one would assume they spent similar time developing as well) can be? Just trying to understand-lol

[Anri]

Ahhh, sorry brother, not poking fun…but your words/sentences are just a bit difficult to follow sometimes-lol. It seemed that you were suggesting altering cam timing or something to reduce stress on the bottom end…guess I was the only one to see it that way.

Sooo, you’re saying that the factory balancer can’t be improved upon because BMW engineers spent thousands of hrs developing/testing, but the factory crankshaft (that one would assume they spent similar time developing as well) can be? Just trying to understand-lol

Stan,

Never forget there is always room to improve...with very little
altho they did a fantastic job already.

For example the S54 wrist pin weighs Xgr. Is there room
to go 85grams x 6 ? absolutely.


The S54 rotating assembly balance have not changed since 1983.
Pistons weight vary 1gr here 3gr there...so do the rods...I am actually
surprised to see an engine with 8000rpm to have that much weight
variation inbetween. I always balance the stock/std parts when they
go back together. Its not that BMW does not what they are doing
but it works yeah..also remember road car is not a race car...its
not that critical. But I am sure on their P54 the parts are balanced
to +/-.05gr and down.

The oldest Engineering saying "Good enough is the enemy of perfection"


S54 rod length is 139mm, will 142mm rod fit so that we can improve
the rod ratio ?, absolutely. BMW favored the shorter rod vs pushing
the ring pack up towards TDC because on the table of the 2 choices
rod ratio has the less affect on things vs how much the rings will
suffer by getting closer to TDC, specially near the rod bolts threads...

Stan, remember this engine is designed to do 7950rpm. Show me 1
M3 in your caliper build that has been tuned with stock rev limiter ?
If there are, its clever choice, but those who push power its alway
over 8000+ for sure.

Bellow I will describe what BMW did thru the life on the inline-6 and
the issues BMW was facing so you can see how much is changed for
very little either 500revs or 4mm increased stroke.

Gen-1 S38 B35 crank material is CrMo45 rev limiter was 6500rpm.
When push 7000rpm+ Issue is OD on the snout is way to small and
when the crank twists the snout so much that damper can't do its
intended job. Also the snout has thread and a nut is holding up the parts
together. Issues are damages on the wood roof key, key way etc loose
nut and damper will run away form the engine.
Damper front sandwich has integrated water pump pulley and that
is NOT good because when the damper is absorbing the vibrations
the Water-Pump drag is interrupting this process.

Gen-2 S38-B36 Crankshaft moved to CrMo42 material, Snout
OD grew and the snout twist was reduced but still existed but its
was pushed much in a higher revs than the Gen-1 and say 7800rpm i
s not a problem with Gen-2, The damper water pulley was removed
and it was designed to be bolted direct to the crankshaft. Long bolt was used
vs nut. Issues: When one starts to push S38B36 to 8000rpm+ the
snout is twisting just as bad as on Gen1 and its damaging slowly the
woodroof key and the crank hub inside.

Gen-3 S38-B38 with its increased stroke they re-designed the snout, again !
This was the final Crankshaft snout revision BMW did under their testing program.
From S38-B38 up to S65 the snout remains the same design via 4 bolts
if not mistaken the S54 is using S38-B38 snout bolts, interchangeable
(have to confirm I have both in hand)

My point to you is if one remains on 8000rpm the factory parts work
wonderful. But as I described above when the revs are pushed higher
then the crankshaft design must be changed!

Stan, let say hypothetical BMW made Gen-2 S54 and it was meant to do
8500rpm from the factory with Warranty. Believe me BMW would have
done changes to the crankshaft and other parts to work with the increased
500rpm ! just follow the history above.

Follow the progress, follow the improvements, understand the engineering
behind.

I am not ready yet to reveal the alterations I have in mind to apply on the S54
bottom. We will see if I have the necessary budget to put this engine together
and perform a test track/street etc, take it a part and see what's up..It's fun.


S54 is one very expensive "Love" when one starts asking for power. 10.000
15.000 its not enough.....you know how it is Stan. 3 here 5 there 7 later...
it piles up...

I always say, those who can't justify the cost leave it stock sell the car
etc...Or go buy an M4 and forget about power issues...Those who wants to push
S54 NA platform further up have to spent the coin and enjoy the increased results
on its own!

Fanatics on NA power like I consider myself you will always see with expensive
"hot-rodded" NA engine.

Regards,
Anri

[digger]

What is the purpose of the new damper? replace the OEM one for stock engine that is too much $$$? or is it one tuned for a modified engine? ATI is the goto and this is the consensus industry wide but damper can do only so much, obviously need to sort the belt issues but it seems weird, haven't people been using this for years?

Its not hard to improve on the factory stuff, lighter reciprocating and rotating mass increases the natural frequency, then there are billet cranks with strategic lightening and strengthening but you are looking at $5k+ for a quality crank at a minimum. There isn't much scope for stiffening a crank as your mains and crankpins are kind of fixed so the overlap of them is fixed aswell, so for the most part its about maintaining stiffness and making it lighter which is definitely doable and improving the fatigue strength with optimised geometry, improved mechanical properties and heat treatment/finishing.

The 2JZ has a similar bore spacing and aftermarket stroker cranks up to around 94-96mm that turn pretty high so all been done before

[stash1]

Stan,

Never forget there is always room to improve...with very little
altho they did a fantastic job already.

For example the S54 wrist pin weighs Xgr. Is there room
to go 85grams x 6 ? absolutely.


The S54 rotating assembly balance have not changed since 1983.
Pistons weight vary 1gr here 3gr there...so do the rods...I am actually
surprised to see an engine with 8000rpm to have that much weight
variation inbetween. I always balance the stock/std parts when they
go back together. Its not that BMW does not what they are doing
but it works yeah..also remember road car is not a race car...its
not that critical. But I am sure on their P54 the parts are balanced
to +/-.05gr and down.

The oldest Engineering saying "Good enough is the enemy of perfection"


S54 rod length is 139mm, will 142mm rod fit so that we can improve
the rod ratio ?, absolutely. BMW favored the shorter rod vs pushing
the ring pack up towards TDC because on the table of the 2 choices
rod ratio has the less affect on things vs how much the rings will
suffer by getting closer to TDC, specially near the rod bolts threads...

Stan, remember this engine is designed to do 7950rpm. Show me 1
M3 in your caliper build that has been tuned with stock rev limiter ?
If there are, its clever choice, but those who push power its alway
over 8000+ for sure.

Bellow I will describe what BMW did thru the life on the inline-6 and
the issues BMW was facing so you can see how much is changed for
very little either 500revs or 4mm increased stroke.

Gen-1 S38 B35 crank material is CrMo45 rev limiter was 6500rpm.
When push 7000rpm+ Issue is OD on the snout is way to small and
when the crank twists the snout so much that damper can't do its
intended job. Also the snout has thread and a nut is holding up the parts
together. Issues are damages on the wood roof key, key way etc loose
nut and damper will run away form the engine.
Damper front sandwich has integrated water pump pulley and that
is NOT good because when the damper is absorbing the vibrations
the Water-Pump drag is interrupting this process.

Gen-2 S38-B36 Crankshaft moved to CrMo42 material, Snout
OD grew and the snout twist was reduced but still existed but its
was pushed much in a higher revs than the Gen-1 and say 7800rpm i
s not a problem with Gen-2, The damper water pulley was removed
and it was designed to be bolted direct to the crankshaft. Long bolt was used
vs nut. Issues: When one starts to push S38B36 to 8000rpm+ the
snout is twisting just as bad as on Gen1 and its damaging slowly the
woodroof key and the crank hub inside.

Gen-3 S38-B38 with its increased stroke they re-designed the snout, again !
This was the final Crankshaft snout revision BMW did under their testing program.
From S38-B38 up to S65 the snout remains the same design via 4 bolts
if not mistaken the S54 is using S38-B38 snout bolts, interchangeable
(have to confirm I have both in hand)

My point to you is if one remains on 8000rpm the factory parts work
wonderful. But as I described above when the revs are pushed higher
then the crankshaft design must be changed!

Stan, let say hypothetical BMW made Gen-2 S54 and it was meant to do
8500rpm from the factory with Warranty. Believe me BMW would have
done changes to the crankshaft and other parts to work with the increased
500rpm ! just follow the history above.

Follow the progress, follow the improvements, understand the engineering
behind.

I am not ready yet to reveal the alterations I have in mind to apply on the S54
bottom. We will see if I have the necessary budget to put this engine together
and perform a test track/street etc, take it a part and see what's up..It's fun.


S54 is one very expensive "Love" when one starts asking for power. 10.000
15.000 its not enough.....you know how it is Stan. 3 here 5 there 7 later...
it piles up...

I always say, those who can't justify the cost leave it stock sell the car
etc...Or go buy an M4 and forget about power issues...Those who wants to push
S54 NA platform further up have to spent the coin and enjoy the increased results
on its own!

Fanatics on NA power like I consider myself you will always see with expensive
"hot-rodded" NA engine.

Regards,
Anri

Appreciate your knowledge, insight, and passion as always Anri (thanx brother), but I was really just asking a simple question to the forum...does anyone have any practical experience w/the Ross balancer-lol I do very much look forward to hearing more about your bottom-end parts when/if they become available though! Please share w/the forum if you have any more updates...maybe start a separate thread to discuss?

[stash1]

What is the purpose of the new damper? replace the OEM one for stock engine that is too much $$$? or is it one tuned for a modified engine? ATI is the goto and this is the consensus industry wide but damper can do only so much, obviously need to sort the belt issues but it seems weird, haven't people been using this for years?

Its not hard to improve on the factory stuff, lighter reciprocating and rotating mass increases the natural frequency, then there are billet cranks with strategic lightening and strengthening but you are looking at $5k+ for a quality crank at a minimum. There isn't much scope for stiffening a crank as your mains and crankpins are kind of fixed so the overlap of them is fixed aswell, so for the most part its about maintaining stiffness and making it lighter which is definitely doable and improving the fatigue strength with optimised geometry, improved mechanical properties and heat treatment/finishing.

The 2JZ has a similar bore spacing and aftermarket stroker cranks up to around 94-96mm that turn pretty high so all been done before

Hey digger, sooo, I'm gathering parts to build a new bullet (non-stroker), and was really just curious if anyone had any practical experience w/the Ross balancer. To directly answer your question, I was looking for a balancer that could control harmonics, at least as good as the factory damper, if not better w/o breaking the bank. Not that it's that much cheaper than a factory one, but hey, if it's effective and a quality product...then why not? I'm sorry, but I don't have any direct experience w/the ATI damper...only the issues that I've seen here and elsewhere so I can't really comment on it.

[EthanolTurbo]

Stan,

Never forget there is always room to improve...with very little
altho they did a fantastic job already.

For example the S54 wrist pin weighs Xgr. Is there room
to go 85grams x 6 ? absolutely.


The S54 rotating assembly balance have not changed since 1983.
Pistons weight vary 1gr here 3gr there...so do the rods...I am actually
surprised to see an engine with 8000rpm to have that much weight
variation inbetween. I always balance the stock/std parts when they
go back together. Its not that BMW does not what they are doing
but it works yeah..also remember road car is not a race car...its
not that critical. But I am sure on their P54 the parts are balanced
to +/-.05gr and down.

The oldest Engineering saying "Good enough is the enemy of perfection"


S54 rod length is 139mm, will 142mm rod fit so that we can improve
the rod ratio ?, absolutely. BMW favored the shorter rod vs pushing
the ring pack up towards TDC because on the table of the 2 choices
rod ratio has the less affect on things vs how much the rings will
suffer by getting closer to TDC, specially near the rod bolts threads...

Stan, remember this engine is designed to do 7950rpm. Show me 1
M3 in your caliper build that has been tuned with stock rev limiter ?
If there are, its clever choice, but those who push power its alway
over 8000+ for sure.

Bellow I will describe what BMW did thru the life on the inline-6 and
the issues BMW was facing so you can see how much is changed for
very little either 500revs or 4mm increased stroke.

Gen-1 S38 B35 crank material is CrMo45 rev limiter was 6500rpm.
When push 7000rpm+ Issue is OD on the snout is way to small and
when the crank twists the snout so much that damper can't do its
intended job. Also the snout has thread and a nut is holding up the parts
together. Issues are damages on the wood roof key, key way etc loose
nut and damper will run away form the engine.
Damper front sandwich has integrated water pump pulley and that
is NOT good because when the damper is absorbing the vibrations
the Water-Pump drag is interrupting this process.

Gen-2 S38-B36 Crankshaft moved to CrMo42 material, Snout
OD grew and the snout twist was reduced but still existed but its
was pushed much in a higher revs than the Gen-1 and say 7800rpm i
s not a problem with Gen-2, The damper water pulley was removed
and it was designed to be bolted direct to the crankshaft. Long bolt was used
vs nut. Issues: When one starts to push S38B36 to 8000rpm+ the
snout is twisting just as bad as on Gen1 and its damaging slowly the
woodroof key and the crank hub inside.

Gen-3 S38-B38 with its increased stroke they re-designed the snout, again !
This was the final Crankshaft snout revision BMW did under their testing program.
From S38-B38 up to S65 the snout remains the same design via 4 bolts
if not mistaken the S54 is using S38-B38 snout bolts, interchangeable
(have to confirm I have both in hand)

My point to you is if one remains on 8000rpm the factory parts work
wonderful. But as I described above when the revs are pushed higher
then the crankshaft design must be changed!

Stan, let say hypothetical BMW made Gen-2 S54 and it was meant to do
8500rpm from the factory with Warranty. Believe me BMW would have
done changes to the crankshaft and other parts to work with the increased
500rpm ! just follow the history above.

Follow the progress, follow the improvements, understand the engineering
behind.

I am not ready yet to reveal the alterations I have in mind to apply on the S54
bottom. We will see if I have the necessary budget to put this engine together
and perform a test track/street etc, take it a part and see what's up..It's fun.


S54 is one very expensive "Love" when one starts asking for power. 10.000
15.000 its not enough.....you know how it is Stan. 3 here 5 there 7 later...
it piles up...

I always say, those who can't justify the cost leave it stock sell the car
etc...Or go buy an M4 and forget about power issues...Those who wants to push
S54 NA platform further up have to spent the coin and enjoy the increased results
on its own!

Fanatics on NA power like I consider myself you will always see with expensive
"hot-rodded" NA engine.

Regards,
Anri

Great post and info. Thanks a lot. I have my stroker S38 revving to 7500 RPM, and spoke to another guy who also has a Korman Motors stroker and has been running it for 90k miles so I guess the upgraded crank/internals really are better for higher revs on S38.

[Randall921]

I have one on my car. Thought I’d give it a try after reading about the problems with the VAC/ATI product (plus I’d rather not give another dime to VAC).

It’s a pretty mild build with stock compression CP pistons, Molnar rods, Schrick cams, completely stock head besides that. I think the limiter is 8400 but I try to stay off it when possible.

Dyno’d at 360 whp and has survived a few DEs and a club race. Hasn’t blown up yet (knock on wood). I’m afraid I don’t have much to offer beyond that.


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