272 HP

[Suprgnat]

Expanding on a discussion started in another thread, I'm now very curious.

Looking at the E70 X5 and its 272 HP I'm wondering what BMW did to "castrate" the N52 in the 128i. The E70 uses the same cylinder head, valves, cams, actuators, injectors, pistons, and a DISA manifold. It has different exhaust manifolds and exhaust, and different intake airbox stuff (is the resonator for sound or flow..?).

272 HP with the cats.

Seems like DISA with a tune should yield great numbers without the need for headers, etc. unless BMW used magic intake and exhaust pipes on the X5. Do companies like Evolve do any kind of reverse engineering of the factory tunes? Would the stock X5 state of tune work in a 128i?

What with the headers and such maybe TheSt|G IS pushing close to 300 HP at the crank. The deeper I dig, the more I'm starting to believe
Stop working 12 hour days! It's killing me!

I would also think that the N51 would respond phenomenally to a tune, despite air pumps, secondary cats, a slightly lower compression ratio and only 91 octane (in California).

[TheSt|G]

I really don't think my butt dyno is unreasonable, especially given one of my previous cars was a dyno'd 300hp BMW(E36 M3) at roughly the same weight and such.

[Dafttt]

I'm going to play Devil's advocate here. No one on e90post has come close to 300hp with similar bolt-ons and headers as you. Your SuperSprint headers are a win over examples like MMW, but those cars still only hit around 270hp.

I do have some reservations about this nicely rounded '300hp' number, but believe me, I'm rooting for you man.

Off topic but I just picked up a euro box and I'm curious if you kept the stock filter or swapped it for something else.

[Suprgnat]

Originally Posted by Daft Auto

I'm going to play Devil's advocate here. No one on e90post has come close to 300hp with similar bolt-ons and headers as you. Your SuperSprint headers are a win over examples like MMW, but those cars still only hit around 270hp.

270 HP at the wheels equals ~310 HP at the crank, and at the crank is how all SAE factory HP numbers are derived.

[Dafttt]

Originally Posted by Suprgnat

270 HP at the wheels equals ~310 HP at the crank, and at the crank is how all SAE factory HP numbers are derived.

Mate, I'm talking about crank.

Turner and RMP can squeeze a lot out of these engines, I think with the latter hitting as far as 280whp*, but to replicate their results or near with a euro box, DISA, headers, and tune seems like a stretch. Again, others have tried and only faired as far as ~280hp(I moved this number up), or roughly 236whp(this too), with the same modifications. By the way, this was an e90 330i too, if I'm not mistaken.

*With a custom radiator, custom headers, custom exhaust, custom camshaft, custom head, upgraded water pump, Motec M800 ECU, and race gas.

EDIT: I searched for a while, but can't find those dyno numbers for reference anymore, so I'm shooting blind. Would someone gladly prove me wrong? Again, I just want to see some solid numbers from users with headers, DISA, and tune - so I can throw my money that direction.

Video description:
This E9X 328i has a 3 Stage Manifold, Stage 3 AA Software, Supersprint headers, Eisenmann Rear Exhaust
Mustang Dyno - 215 whp

[Suprgnat]

Most of the 128i dyno charts I've seen are about 198 HP at the wheels. Given the 230 HP by BMW, that would imply a 32/230 13.9% drive train loss. The X5 i mentioned earlier is rated at 272 HP or 42 HP more through the cats with an engine that's basically identical from the intake manifold (w/DISA) to the exhaust ports and and fully EPA compliant. That equates to an additional 34.16 HP at the wheels on a 128i. Evolve is saying 15-20 HP for their stage 2 DISA tune, yet the (conservative) factory yields more.

So, are the X5's (and X3's) intake muffler and exhaust system really that much better? Are the tuners at BMW just that good? Does a decent set of headers on a 272 HP engine gain no HP?

[Bimmer-Bob]

Assuming 272 HP as a pre-header starting point is absolutely asinine with no data to support it. You can't just look at BMW's best spec N52 and assume that Evolve is matching it. Don't any of you have science or technical backgrounds? All of this talk w/o data is just that - talk.

[Iron Man]

Originally Posted by Suprgnat

Most of the 128i dyno charts I've seen are about 198 HP at the wheels. Given the 230 HP by BMW, that would imply a 32/230 13.9% drive train loss. The X5 i mentioned earlier is rated at 272 HP or 42 HP more through the cats with an engine that's basically identical from the intake manifold (w/DISA) to the exhaust ports and and fully EPA compliant. That equates to an additional 34.16 HP at the wheels on a 128i. Evolve is saying 15-20 HP for their stage 2 DISA tune, yet the (conservative) factory yields more.

So, are the X5's (and X3's) intake muffler and exhaust system really that much better? Are the tuners at BMW just that good? Does a decent set of headers on a 272 HP engine gain no HP?

I think Turner quotes adding a DISA+tune, keeping all else stock, will get the N52 to 260 HP. I would think if you could improve the engine breathing by adding an intake, could probably push that another 5-10 HP (provided the tune can optimize for it). Add better breathing headers, without cats, I would think you could easily be in the 280+ HP region.

[Suprgnat]

Originally Posted by Bimmer-Bob

Assuming 272 HP as a pre-header starting point is absolutely asinine with no data to support it. You can't just look at BMW's best spec N52 and assume that Evolve is matching it. Don't any of you have science or technical backgrounds? All of this talk w/o data is just that - talk.

Um, I did look at BMW's best spec'ed N52. 272 HP is the power stated by BMW for the N52B30 in the E70 X5 3.0si and E83 X3 3.0si. Is that enough data to support it? Yes, I have a technical background. I can read and research, too. Obviously you didn't before calling BS. And, I never assumed Evolve was matching it. I stated quite clearly that they weren't and asked why.

Here's what I said:

Originally Posted by Suprgnat

Evolve is saying 15-20 HP for their stage 2 DISA tune, yet the (conservative) factory yields more. So, are the X5's (and X3's) intake muffler and exhaust system really that much better? Are the tuners at BMW just that good? Does a decent set of headers on a 272 HP engine gain no HP?

http://www.pml.com.sg/bmw/newvehicle..._catalogue.pdf

I've attached a link to the X3 BMW brochure so you can read it yourself, since you obviously believe I just made up the numbers in my original post.

[Suprgnat]

Originally Posted by Bimmer-Bob

Assuming 272 HP as a pre-header starting point is absolutely asinine with no data to support it. You can't just look at BMW's best spec N52 and assume that Evolve is matching it. Don't any of you have science or technical backgrounds? All of this talk w/o data is just that - talk.

I also said this:

Originally Posted by Suprgnat

Looking at the E70 X5 and its 272 HP I'm wondering what BMW did to "castrate" the N52 in the 128i. The E70 uses the same cylinder head, valves, cams, actuators, injectors, pistons, and a DISA manifold. It has different exhaust manifolds and exhaust, and different intake airbox stuff (is the resonator for sound or flow..?).

I didn't just pop the hood on an X5 and say "That looks about the same." I spent a considerable amount of time on Realoem comparing part numbers. Sorry I didn't write down the side by side comparison for your benefit.

Why you so angry?

[Bimmer-Bob]

I'm not angry at all. I just said that you couldn't look at BMW's best-spec N52 (yes, the one in the X3 & X5) and assume that tuners could match it. Yet you continue to quote X3 numbers for some reason.

[Suprgnat]

Originally Posted by Bimmer-Bob

I'm not angry at all. I just said that you couldn't look at BMW's best-spec N52 (yes, the one in the X3 & X5) and assume that tuners could match it. Yet you continue to quote X3 numbers for some reason.

No one assumed anything. I asked specifically why tuners couldn't match it. I quote X3/5 numbers because it proves that those numbers are achievable with the N52B30 engine and selected their best spec'ed N52 because one has to set goals. Why wouldn't that be "The Best"?

Again, what I said:

Originally Posted by Suprgnat

So, are the X5's (and X3's) intake muffler and exhaust system really that much better? Are the tuners at BMW just that good? Does a decent set of headers on a 272 HP engine gain no HP?

That is an interrogative not declarative statement.

[Bimmer-Bob]

Originally Posted by Suprgnat

No one assumed anything. I asked specifically why tuners couldn't match it. I quote X3/5 numbers because it proves that those numbers are achievable with the N52B30 engine and selected their best spec'ed N52 because one has to set goals. Why wouldn't that be "The Best"?

Again, what I said:

That is an interrogative not declarative statement.

Not trying to be argumentative, but when you say "Does a decent set of headers on a 272 HP engine gain no HP?" that sounds an awful lot like you're assuming 272 HP as a pre-header starting point.

[Suprgnat]

Originally Posted by Bimmer-Bob

Not trying to be argumentative, but when you say "Does a decent set of headers on a 272 HP engine gain no HP?" that sounds an awful lot like you're assuming 272 HP as a pre-header starting point.

Yes, I chose 272 HP as a pre-header starting point as it has been proven conclusively to me by BMW that one does not need headers on an N52 to achieve those figures. The question has more to do with whether BMW has wrung all the HP that can be had from the N52 regardless of the addition of headers. I don't think so but I, just like you, am awaiting proof. I have seen numbers quoted as high as 298 HP at the wheels (~340 crank HP) for a full race N52 motor, but seen no dyno slips to back it up.

[ilikebmxbikes]

Stig, please Dyno. A lot of people would benefit if you are hitting your claimed number and it would eliminate a lot of this speculation. What ever number you land on, you would be doing the forums a service.

[Dafttt]

Originally Posted by Suprgnat

Yes, I chose 272 HP as a pre-header starting point as it has been proven conclusively to me by BMW that one does not need headers on an N52 to achieve those figures. The question has more to do with whether BMW has wrung all the HP that can be had from the N52 regardless of the addition of headers. I don't think so but I, just like you, am awaiting proof. I have seen numbers quoted as high as 298 HP at the wheels (~340 crank HP) for a full race N52 motor, but seen no dyno slips to back it up.

Conclusively? Where are you finding these numbers?

I've never seen any x28i dyno and hit 272 crank HP, with full bolt ons, tune, and SuperSprint headers.

Doing the 'math' is pure speculation. None of this means anything without actual dyno charts - and I'm not referring vender claims or to what Evolve has posted. Either way, I'll be in this boat pretty soon, with numbers to put this argument to rest.

[Suprgnat]

Originally Posted by Daft Auto

Conclusively? Where are you finding these numbers?

I've never seen any x28i dyno and hit 272 crank HP, with full bolt ons, tune, and SuperSprint headers.

Doing the 'math' is pure speculation. None of this means anything without actual dyno charts - and I'm not referring vender claims or to what Evolve has posted. Either way, I'll be in this boat pretty soon, with numbers to put this argument to rest.

Please look at the PDF I linked to. It's BMW that's making the claim. X3/X5 3.0 si.

[ilikebmxbikes]

Originally Posted by Suprgnat

Please look at the PDF I linked to. It's BMW that's making the claim. X3/X5 3.0 si.

You are comparing crank HP and dynos are WHP. 272HP probably will dyno more around 230-245 whp (my guess)

[Suprgnat]

Originally Posted by ilikebmxbikes

You are comparing crank HP and dynos are WHP. 272HP probably will dyno more around 230-245 whp (my guess)

That's actually what I said:

Originally Posted by Suprgnat

Most of the 128i dyno charts I've seen are about 198 HP at the wheels. Given the 230 HP by BMW, that would imply a 32/230 13.9% drive train loss. The X5 i mentioned earlier is rated at 272 HP or 42 HP more through the cats with an engine that's basically identical from the intake manifold (w/DISA) to the exhaust ports and and fully EPA compliant. That equates to an additional 34.16 HP at the wheels on a 128i.

198+34.16=232.16 HP at the wheels

[ilikebmxbikes]

Originally Posted by Suprgnat

That's actually what I said:

198+34.16=232.16 HP at the wheels

misunderstood where u are coming from

[strati1]

Originally Posted by ilikebmxbikes

Stig, please Dyno. A lot of people would benefit if you are hitting your claimed number and it would eliminate a lot of this speculation. What ever number you land on, you would be doing the forums a service.

This, for the love of god end this squabbling mess.

[TheSt|G]

I'm was looking to get my muffler on before I do, but perhaps I should just focus on the dyno done before this section explodes.

Don't forget the guy running 340hp+ with the cams, individual throttle bodies, motec, and a few other bits.