S54 Stroker build

[ethan]

"Not a bad way to spend $(3)0,000 dollars" - Dom, probably.

[stash1]

Lang Racing does different stages of head work for your lighter components. You do know this engine is not going to last very long right? What you're wanting is going to cost ALOT of money and reliability is going to be gone.

For compression ratios, I believe once you get to 12.5:1 compression 93 octane isn't going to cut it. You will need to convert to race fuel or by that true E85 online. Look up what a lot of chevy drag racing guys use for fuel.

Bore size can be machined out from 87mm to 87.5mm but not beyond that as there won't be enough metal between the cylinders so it's basically going to be all stroke.

I would look into a standalone ECU that will actually show live data and whatnot for something so high performance. If you don't have a good tuner, this engine will probably blow up quickly.

I don't race cars but this is the information I've pieced together over time from research and school. If I'm not mistaken, 296/288 would be too aggressive to maintain the vanos. The vanos can only advance timing so much and once you start adding so much duration in, advancing becomes difficult. A valve could hit a piston much easier.

Lightening up valvetrain components significantly decreases durability. Titanium parts are crazy light but aren't as durable. Valve shims might start flying if you rev too high as well.

I want to see you succeed at this because N/A engines are quite superior when engineered right. They tend to be more efficient even if they don't put out more power.

No, you're mistaken, it's entirely possible to run big boy cams in an S54...and retain VANOS. The Schrick cams that you're both referencing are actually 304/296 duration specs, and it's actually more the lift than duration that gets you into trouble. Both the 288/280 and 304/296 are available in high lift versions (14mm), and this is where you could possibly run into trouble and would need to double check piston-to-valve clearances. At this level though, most folks would be running custom aftermarket pistons, and they can be designed w/custom reliefs in the piston tops to account for the higher lift cams. Even an 'off the shelf' piston could have deeper reliefs machined into the top to accommodate higher lift cams.

Also, I believe that ST has developed a shim conversion kit that all but eliminates the worry of spitting shims out. Mike @ MaxPSI ran this set up successfully in his turbo car. OP, sounds like it could be an epic build, but I would encourage you to do more research on part selection and maybe talk to the folks over at Partee racing. I've read about a few of their recent S54 builds, and they could be a good source of info as well. Also, maybe try contacting Matt Coyne @ Coyne Performance as he has a lot of experience building S54's as well. GL!

EDIT: OP, to answer a couple of your other questions:

!. I believe that you can make 400WHP keeping it a 3.2, but of course stroking it would add a little bit more HP and more importantly-torque...which these engines can certainly use!.
2. I think that you will need to bump comp. ratio to either 12.0:1 or 12.5:1 to achieve your 400WHP goal. Anything above 13.0:1 is probably unnecessary, and would most certainly require a steady diet of either race fuel or E85/100.

[jvit27]

You should also ask yourself where you plan to race this car down the road and try to at least futureproof if... you could very well spend a ton of money on a motor that is not legal or competitive by then.

[Daniel]

When you do get around to building, please document it! Very interested in seeing this build and your justification on parts you're using

[Arith2]

Lang Racing does different stages of head work for your lighter components. You do know this engine is not going to last very long right? What you're wanting is going to cost ALOT of money and reliability is going to be gone.

For compression ratios, I believe once you get to 12.5:1 compression 93 octane isn't going to cut it. You will need to convert to race fuel or by that true E85 online. Look up what a lot of chevy drag racing guys use for fuel.

Bore size can be machined out from 87mm to 87.5mm but not beyond that as there won't be enough metal between the cylinders so it's basically going to be all stroke.

I would look into a standalone ECU that will actually show live data and whatnot for something so high performance. If you don't have a good tuner, this engine will probably blow up quickly.

I don't race cars but this is the information I've pieced together over time from research and school. If I'm not mistaken, 296/288 would be too aggressive to maintain the vanos. The vanos can only advance timing so much and once you start adding so much duration in, advancing becomes difficult. A valve could hit a piston much easier.

Lightening up valvetrain components significantly decreases durability. Titanium parts are crazy light but aren't as durable. Valve shims might start flying if you rev too high as well.

I want to see you succeed at this because N/A engines are quite superior when engineered right. They tend to be more efficient even if they don't put out more power.

[D-O]

Have you considered contacting Lang Racing Development? They are highly regarded and offer S54 stroker kits and components.

Jesse

[M/Anthony]

Hello all,

I have a spare S54B32 long block with 137k miles (40-50 ish k on tranny) from my previous m3. I plan to rebuild the entire engine than swap it into an e46 m3. I want to stroke my S54 to either a 3.4L or 3.5L. I do not have any intentions with forced induction, as I dream to have an overbuilt, overengineered naturally aspirated s54. This will not be a race engine but will see hard-driving, many track days, and very few daily driving miles, possibly a gts4 car way in the future. Its main purpose is to be a very hardcore car basically. While there is some information out there and I have already contacted an S54 specialist (VAC), I needed some information a little bit faster on my direction for stroker parts. My main question is what Bore size and compression ratio I should run. I know the stock s54 runs an 11:5:1 but will 12:1, 12:5:1 be more feasible or even 13:1? This isn't my realm exactly and that is why I need your input on the best compression ratio, bore size, and camshafts. I would like to run bigger than 288/280 as BMW Motorsport put out I believe 296/288 cams for the S54 ( not totally confident on that). I would like to achieve 400+rwhp as I will be adding lighter drivetrain components like carbon driveshaft, lighter clutch, etc. Kits possibly? Finally, I want to retain VANOS to keep with the nature of the car and the driveability of it. Thank you and any help or reference to other engine builders/ people that can help will be greatly appreciated.

Anthony