How much power can I get naturally aspirated?

[AS007]

I have a 328Ci with:
Headers
UUC TSE2
Pulleys
Shark Injector
CAI
3.46 diff
UUC Stage 2 clutch
JB Racing 10lb flywheel

I dynoed at 199.2rwhp and 209.6ft/lbs yesterday.

So with:
Technik 264/248 cams
Technik Stage 3 ported cylinder head
Valvesprings, retainers, lifters.
12.5.1 compression pistons
Forged Rods
Intake Manifold
Throttle Body
and some fuel upgrades, what kind of power do you think I will put down? Also where can I find the pistons,valves,manifold,throttle body?
And isn't there a stroker kit availible for our cars? Thanks for any input, I really want to do this project because not many people go NA.

[redronin]

only 1 way to find out :buff:

[BMWPower06]

wouldnt it have been cheaper to just SC?

[BMWPower06]

PS- how much do headers run?

[russ330]

Try contacting Samir @ Technik for a guesstimate on the power output. As you've said not many people have gone that route, so not many people know what type of power you would put down.

[AS007]

It would be much cheaper to supercharge, it's very tempting and I may do it but I just want to see how much power I can get out of this motor, and it will sound sick when it is done naturally aspirated. I will contact them, thanks. PS- they were $1025 shipped through a group buy from Technik but I think they are $1,250 normally.

[Bim Growl]

I've done everything there except for the higher compression. I've run between 250-265 to the wheels. That is a tricky game to play to build your engine like you're thinking. If you go that far, it would be worth your while to get a completely new ECU, like Motec, to give you a higher redline, and to remap all of your performance data. This is going to be big big money...

Doing everything above that you've got listed, and keeping the stock ECU would probably get you up to 300 rwhp. If you use Motec, that number could jump significantly. But this is going to be a very tricky engine that will need a lot of care.

Remember race built engines aren't in daily drivers for a reason... Also, don't forget the little stuff that will pop up like a new oil pump, and higher flow injectors. You'll also most likely need an oil cooler, etc... I would add up the cost of what you've listed, and double or triple it to give you an idea of the resources you'll need to make this happen properly. It's not just a matter of throwing these parts on the car, it's a matter of quite a bit of R & D work as well.

How many 12.5:1 3.0 liter engines do you see on this site? Hmmmmm. Now do you think there could be a reason for that?

Consult a professional like Turner Motorsports or Vac Motorsports to see what they think...


You are right wabout one thing though. It does sound sick!!!!

[bmwstephen]

you have 199 rwhp on a 328ci? thats freggin impressive of a 2.8l thats how much the average 330i driver gets.!!!

[AS007]

So do you think $13,000 would cover it? How much does a Motec engine management cost? Bim Growl do you have any videos of your car?

[sjo328ci]

You'll have a very hard time running 12.5 compression on premium pump gas. Even the M3 runs only 11.5. The ECU will back the ignition timing off to protect the engine when it senses the detonation that will inevitably occur, and when it does, you won't get the power you expected anyway. Limit the compression ratio to 11.5:1 and you should be OK.
I am working with Technik Engineering on exactly the same configuration that you described with 11.5 compression. PM me for details.

[BMWE46Fl]

So do you think $13,000 would cover it? How much does a Motec engine management cost? Bim Growl do you have any videos of your car?
i'm using their M880 and adl dash, if you go stand alone you will have to get some form of dash cluster becuase the stock one will no longer work

[AS007]

Is there a stroker kit availible for our cars? I think Hartge....maybe:hmm:

[joema]

I know it's already been said, but I STRONGLY suggest just putting a supercharger on it. You'll get more reliable hp more cheaply than any normally aspirated method.

The ESS twin-screw supercharger should eventually be available for the 328i, and would probably be the most impressive: http://forum.e46fanatics.com/showthread.php?t=355037 However any of the mainstream centrifugal supercharger kits (Technik, AA, VF, ESS) would work very well.

[AS007]

How much of a gain should I expect if I installed the cams in my car as it is now?

[pei330ci]

Power is addictive, you won't be happy with JUST the cams.

Cams will give you approximately 20 Hp.

A supercharger will give you more bang for the buck.

[AS007]

20rwhp? And how much does install usually run?

[pei330ci]

Samir can clarify the actual Hp a bit better than I can on a 328, as I only speak from experience with my 330Ci. For me, it was 20rwhp.

Install for my car was about 10 hrs. That said, its NOT something for inexperienced mechanics to do. I've heard quite a few horror stories about installing cams on an M54 engine, including a factory trained BMW tech at a BMW dealership with all the factory tools taking 3 days. There are fewer things that can be messed up doing a SC install, and it takes close to the same amount of labour as cams.(A tiny bit more in most cases)

[TxZHP04]

So do you think $13,000 would cover it?

I believe you're looking at more like $20 - $40k. :yikes: It's definitely a one thing leads to another kind of project... and the cost depends on how much you can do yourself, how much "experimenting" has to be done to get everything right, and how many "mistakes" are made along the way.

[Activ3]

I think RD has a stroker kit, bumps it up to 3.5L

[sjo328ci]

Keep in mind with stroker kits that increasing stroke will increase peak piston speed in direct proportion and will thus increase friction and wear at the piston skirt/cylinder wall interface. The 328 is exactly "square" with stroke and bore equal at 84 mm, while the 330 is "undersquare" at 89.6/84 mm. Oversquare (typically .8-.9 stroke/bore ratio) is generally favored for performance engines because it allows a higher maximum crankshaft speed (i.e. "redline") for a given displacement. Formula 1 engines are able to rev to 19-20,000 rpm by using stroke/bore ratios of about .4, i.e. stroke is only 40 percent of the bore diameter.