S54 Stroker build

[jbfrancis3]

CSL BMEP = 4π(370.1383Nm) / (3.246L * 100) = 14.33. Pretty impressive given that it's an I6 so it has to have small pistons and long stroke. HP/liter is a better number for the S54 of course...

Are 355Nm and 365Nm correct torques figures for the US/CAN M3 and Rest of World M3, respectively? If so, that's 13.47 and 14.13.

[M/Anthony]

I just got in contact with Chris Fletcher, I will end up giving him a call this weekend.

[ethan]

CSL BMEP = 4π(370.1383Nm) / (3.246L * 100) = 14.33. Pretty impressive given that it's an I6 so it has to have small pistons and long stroke. HP/liter is a better number for the S54 of course...

[jbfrancis3]

Ahaa, so he takes the micro gain here and there and he combines that number
as sum of 41hp. Then he takes this 41hp gain and adds them on top of the Factory
power of 310-311 SAE Crank HP as a gain and this is how he calculates the
gains for 200 bucks.

This is how the numbers are presented to public as 351 SAE crank HP.

That's simply fraudulent, except that's much too strong a word in a world where there is little enforcement and the consequences are far from life-threatening. But if that marketing creativity were applied in another more critical industry, it would be fraudulent. That aside, we have seen in the last 20 yrs that better communication has allowed more transparency and push-back to these tactics in our world, decreasing their frequency considerably. I like to hear to the stories, though!

Back on topic somewhat, I recommend that the OP and whomever else inclined watch a recent Engineering Explained video. Set aside any preconceptions you may have about the host, qualifications, or whatever may be a first reaction to dismiss it. The video touches on how to box in the goals and expectations for the OP. It covers many themes which have been debated in this thread.

First 1/3 of video: shows the long math, its skippable it needed
Second 1/3 of video: shows how expectations can be boxed in for OP
Final 1/3 of video: covers notion of raising RPM to achieve horsepower

Take a look

https://youtu.be/bE_1JYrlYYU

or

https://www.youtube.com/watch?v=bE_1JYrlYYU&feature=share

[Anri]

Everyone is not using the same ruler to measure

Hi Digger,

The way I approach all of this is more constructive rather than unclear
represented numbers.

Based on your comment there are various rulers and you are spot on,
one of the many rulers is bellow.

20years ago when Dinan was upgrading the E34M5 and S38 engines
his advert was his eprom chip will make your S38-B36 351hp crank.

20 years later still people are believing that their E34M5 3.5 makes
351crank hp.

I was also into this special representation trap up until I took so many S38
engines to a Dyno-Jet and non made 351crank-14%=302rwhp.
No E34M5 3.5 ever was able to make 302rwhp dyno-jet measured, period.
You never ever ever see E34M5 3.5 which makes anything over 270rwhp
on a Dyno-Jet with comes to about 311hp

On my S38 3.5 with large cams intake and hi flow exhaust system I reached
305.5rwhp on a stock engine just cams upgrade.

So were are those promised 351hp as advertised from only Eprom Chip for
200 bucks ?

Here is how he calculates the power. Thru the rev range the power is gained
5hp here 2hp there and at pass 6000rpm the graph is showing no gain of
single hp at were the 110/110 cam timing is set on 3.5 the pick power
never changed at 6900rpm and 7250rpm is the rev limiter, again were is the
351crank hp power from ?

Ahaa, so he takes the micro gain here and there and he combines that number
as sum of 41hp. Then he takes this 41hp gain and adds them on top of the Factory
power of 310-311 SAE Crank HP as a gain and this is how he calculates the
gains for 200 bucks.

This is how the numbers are presented to public as 351 SAE crank HP.

BMW MS when they made the final version of S38-B38 they made so many revisions
on the head, valves, 50mm itb, 0.5CR is raised, list goes all the way down to installing Metallic
Cats in order to reduce back pressure and with all of that they achieved only 340hp DIN ?
Were did they go all wrong ?

When I build S38 for a customer I never represent the HP gain numbers in this way
because I will be embarrassed.

Anyway, as we can all see out there are a lot of people with hi level of requirements
and expectations.

Regards,
Anri

[digger]

Hi,

Man could you please explain to me how on earth you can achieved 400RWHP
out of as you call it "Mild" build with 280/272 cams and E85 ?

If we talk say Dyno-Jet I do consider 13.5-14% drive train loss absolute no more
than that but that is my personal tests I have done. So based on this drive train loss
you are saying that your suggestion will make 468hp at the crank.

Fuck, I wander were BMW Motorsport GmbH went all wrong back in 2001 with their
race engine which target is to survive the given race and that is it, and they never ever
made more than 435-450hp. at the crank..and that is all out P54 engine which means its
race engine and the European measuring tape for HP is DIN not SAE. 141hp per liter DIN.

468hp SAE crank is 146hp per liter...So if convert to DIN this will be legit a tad under 150hp
per liter.

So if you were to build all out S54 engine what would be estimate power 500-550hp crank ?
which is 156hp per liter ?

BMEP on S54 for the given displacement and RPM's will never allow to produce this
level of power ever put on E85. If we put M5+Nitro sure it can make 600hp no problem.

To produce power out of small displacement we need RPM's. Back in 92's those V6
engines were producing nearly 420hp crank out of 2.5 per regs. but ~12000rpm.


This is exactly how people are screwed and fooled. One needs to approach this more
logical rather than "Bro my stock S54 tune by XXX makes 350 wheel dude" let me give
you a ride...

Serious Race engine builds are rated at the Engine Dyno never on chassis dyno...and
with (BMEP) in mind !!!

Regards,
Anri

Everyone is not using the same ruler to measure by, even on the chassis dyno there is a fairly big disparity between dynojet, dyno dynamics and dynocom in terms of the power and torque numbers.

It is probably not a coincidence that most of the big numbers come from the dynocom dyno....there are many instances of comparisons where it produces significantly higher numbers. Personally i rate dynojet as a fairly consistent benchmark and put more weight in numbers from those over some others from a relative standpoint.

It is a can of worms trying to back calc flywheel numbers. One thing for sure is you cant use a fixed %. A stock vehicle might lose 15% but with power mods the absolute hp losses will be fairly unchanged so the % could drop to 10% at peak hp and lower at the peak torque rpm. Its best not to worry about it. Often the factory race engines have a rule set and endurance level with which they need to abide by so its not open slather so these should not be taken as hard limits.

the way to evaluate BS claims is in torque per liter. 460bhp at 8500rpm is still within plausible levels for a NA 4V engine, maybe not the engine spec in question but there are some factory engines that actually produce numbers in the ballpark from Ferrari and the like

[jbfrancis3]

Hasan is making 382 whp with 280/272's on pump gas. E85 would bump those numbers up a smidge. So it's very possible with the right tuning and conditions.

You're thinking too hard at this lol. It's already been done. There's another car in Florida making 394 whp on E85 with the same cam setup albeit with a built head, I believe Lang did his head.

I recently learned about Hassan's instagram. hte_performance-tuning. Of course, now it comes up frequently since I looked once. Such is social media.

Anyway, the most recent post of his discusses light modifications and quotes 355whp. Anyone may look at the details if they choose. I know he is member here and a good contributor.

I would just be careful quoting these one-sie / two-sie cases as if other owners can reliably achieve the same results.

[cozmo kraemer]

Lets semi-start over,
I hear what everyone is saying and I also thank you for your input.
can we shift the build to scrapping 9000rpms as it will be impossible and dangerous
What if we switch to running a higher compression, but also increasing torque.
Going off what Carbahn and Mike run, increasing compression in displacement can be doable, his engine maxes his hp at 8100.
So then, I'm not saying stuff won't be custom and this and that. Making this engine reliable with higher compression and higher torque.
I still believe we can get a pretty aggressive build matched with a high diff ratio.

Just my $.02

In my discussions with Andrew, the path to bigger high rpm power is to de-stroke the engine to a 3.0l, rev it out as far as possible and build it for high RPM only. You sacrifice nearly all streetability, but that is the path to what you the big high rpm power

I think MisterEm on here had a reliable 3.4l stroker that made over 400whp if I remember correctly. I would probably mirror that setup. I think it had the most documented power on the boards. I could be wrong there though, I haven't seen much documented from full stroker builds. I did a lot of research on it when I spun my rod bearing. I thought about going that route but instead went with buying a good used engine, doing rod bearings and putting in the car. That has turned into doing the full cylinder head rebuild and basically replacing everything. I probably would have been better off just rebuilding as a stroker, or at least a wider rod bearing journal crank refresh with forged rods and pistons, slightly higher compression and just slightly more bore to make the cylinders perfect.

I guess we will see what it makes when it is all together. It has been an experience.

[M/Anthony]

Im in this same boat since my head gasket blew and i seemed to have blow by on all cylinders anyway. So this thread has been quite helpful.

Since I am pulling the head, the engine can come out and be gone through. Lang seems to have a nice head rebuild option(for some money, and as was just mentioned, some power). Also he has a crank/piston/bearing package that is very attractive as well,(also for some money) He widens the stock crank rod bearing journals for wider rod bearings and presumably better reliability there. Im not sure if power is lost (if any) by doing this but then they clearance and match all the bearings and balance the parts in house before they send em to you so no guess work or extra tools required. Just bore the cylinder to 87.5 and start building.

If anyone has done either of these builds(the widening or the head build) id love to hear some feedback on them.

Sorry to hear that,

Agreed feedback would be great, thank you to Sharocks for providing a personal build, helps give real-world expectations. Thank you for finding this thread useful, that was one of my goals lol.

I'm awaiting a response from lang but most likely he will be doing a lot of my work, since he's the closet engine builder I know, and he's done great s54 builds so far. Once I get in contact I will ask him with reliability and the steps he will take to ensure that.

And does anyone know of a reputable engine builder where I could bore and sleeve my block near NorCal?

[F1Dryvr]

Im in this same boat since my head gasket blew and i seemed to have blow by on all cylinders anyway. So this thread has been quite helpful.

Since I am pulling the head, the engine can come out and be gone through. Lang seems to have a nice head rebuild option(for some money, and as was just mentioned, some power). Also he has a crank/piston/bearing package that is very attractive as well,(also for some money) He widens the stock crank rod bearing journals for wider rod bearings and presumably better reliability there. Im not sure if power is lost (if any) by doing this but then they clearance and match all the bearings and balance the parts in house before they send em to you so no guess work or extra tools required. Just bore the cylinder to 87.5 and start building.

If anyone has done either of these builds(the widening or the head build) id love to hear some feedback on them.

[Sharocks]

Hi,

Man could you please explain to me how on earth you can achieved 400RWHP
out of as you call it "Mild" build with 280/272 cams and E85 ?

If we talk say Dyno-Jet I do consider 13.5-14% drive train loss absolute no more
than that but that is my personal tests I have done. So based on this drive train loss
you are saying that your suggestion will make 468hp at the crank.

Fuck, I wander were BMW Motorsport GmbH went all wrong back in 2001 with their
race engine which target is to survive the given race and that is it, and they never ever
made more than 435-450hp. at the crank..and that is all out P54 engine which means its
race engine and the European measuring tape for HP is DIN not SAE. 141hp per liter DIN.

468hp SAE crank is 146hp per liter...So if convert to DIN this will be legit a tad under 150hp
per liter.

So if you were to build all out S54 engine what would be estimate power 500-550hp crank ?
which is 156hp per liter ?

BMEP on S54 for the given displacement and RPM's will never allow to produce this
level of power ever put on E85. If we put M5+Nitro sure it can make 600hp no problem.

To produce power out of small displacement we need RPM's. Back in 92's those V6
engines were producing nearly 420hp crank out of 2.5 per regs. but ~12000rpm.


This is exactly how people are screwed and fooled. One needs to approach this more
logical rather than "Bro my stock S54 tune by XXX makes 350 wheel dude" let me give
you a ride...

Serious Race engine builds are rated at the Engine Dyno never on chassis dyno...and
with (BMEP) in mind !!!

Regards,
Anri

Hasan is making 382 whp with 280/272's on pump gas. E85 would bump those numbers up a smidge. So it's very possible with the right tuning and conditions.

You're thinking too hard at this lol. It's already been done. There's another car in Florida making 394 whp on E85 with the same cam setup albeit with a built head, I believe Lang did his head.

[Anri]

Other than it's mildly possible with enough money, OP where do you plan on driving this thing? I have 288/280s with a built/ported head for 9k rpm. I have my redline set at 8500. I'm short shifting usually around town at like 8k.

If this is going into a street car, understand these are PEAK numbers.

If it's gonna be a street car, grab some 280/272's, mildly build your head, run E85 and you should be good for at least very close to 400 rwhp at a useable rpm.

If I was gonna do it over again, I'd go that route.

Hi,

Man could you please explain to me how on earth you can achieved 400RWHP
out of as you call it "Mild" build with 280/272 cams and E85 ?

If we talk say Dyno-Jet I do consider 13.5-14% drive train loss absolute no more
than that but that is my personal tests I have done. So based on this drive train loss
you are saying that your suggestion will make 468hp at the crank.

Fuck, I wander were BMW Motorsport GmbH went all wrong back in 2001 with their
race engine which target is to survive the given race and that is it, and they never ever
made more than 435-450hp. at the crank..and that is all out P54 engine which means its
race engine and the European measuring tape for HP is DIN not SAE. 141hp per liter DIN.

468hp SAE crank is 146hp per liter...So if convert to DIN this will be legit a tad under 150hp
per liter.

So if you were to build all out S54 engine what would be estimate power 500-550hp crank ?
which is 156hp per liter ?

BMEP on S54 for the given displacement and RPM's will never allow to produce this
level of power ever put on E85. If we put M5+Nitro sure it can make 600hp no problem.

To produce power out of small displacement we need RPM's. Back in 92's those V6
engines were producing nearly 420hp crank out of 2.5 per regs. but ~12000rpm.


This is exactly how people are screwed and fooled. One needs to approach this more
logical rather than "Bro my stock S54 tune by XXX makes 350 wheel dude" let me give
you a ride...

Serious Race engine builds are rated at the Engine Dyno never on chassis dyno...and
with (BMEP) in mind !!!

Regards,
Anri

[Obioban]

I love this car and especially the engine but for the price I dont think this engine has more cons than pro's when it comes to adding a stoker. I am happy with a ceiling of 375 reliable whp for the price and risk to reward I think it would be better to just drop a Dinan Built 5.8L v10 If your chasing bmw NA power.

There's a reason you don't see a lot of stroker builds on here. I'd say >90% of people that go past the bolt ons/cams/TBs route end in engine failure, and the additional power to be gained is surprisingly... minimal.
(which makes sense, since going to a 3.4L is only a 6% displacement increase-- so, all else equally optimized (unlikely it will be for the stroker, since it's a less worked out path), 6% more power).

[M3AN ONE]

I love this car and especially the engine but for the price I dont think this engine has more cons than pro's when it comes to adding a stoker. I am happy with a ceiling of 375 reliable whp for the price and risk to reward I think it would be better to just drop a Dinan Built 5.8L v10 If your chasing bmw NA power.

[Sharocks]

thats good to hear that about your valve train lol. This is good information since you've done this. Thank you for sharing your build btw. Your car does look stunning
So gong big duration camshafts aren't the best option and idea basically, don't go higher duration because you lose lower end power. How much of a difference with 288/280 in the top range compared to 280/272?
Are those the Supertech valves that people had issues with? and since they're titanium how often do you have to replace/do valve adjustments?
I will most likely run inconel because there doesn't seem to be a negative to it beside a few more bucks.
What do you mean by a chore to rev it out?
Who did your port and polish?

Thanks, the 288's move the powerband upwards in the rev range. With a proper tune the 280's can do the same but most cars with 280's aren't revving past 8500.

Haven't had an issue with my Supertech parts. Only the valvetrain springs, retainers etc are Titanium. I believe the valves themselves are SS. I'm doing valve adjustments at normal intervals, every 30k or 3 years.

The Inconel ones are a lot cheaper nowadays, this head was built like 8 years ago lol.

The car doesn't make power low end. So it's chore to rev it out because I don't wanna be spinning tires to get up and moving.

Port and polish was done by a local shop in Pittsburgh.