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Does anyone make ported heads for the m5 ? I have seen vettes pick up over 100 rwhp with a good set of heads , I don't see a reason the same can't be done with the m5. Any thoughts ?
 

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Not sure if anyone has brought this up before. I'm not too
familiar with the process but does it not assume that the
heads are not exactly to spec to net some kind of gain?
Seems a bit risky to me but I'd like to hear an expert
opinion.
 

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Does anyone make ported heads for the m5 ? I have seen vettes pick up over 100 rwhp with a good set of heads , I don't see a reason the same can't be done with the m5. Any thoughts ?

The BMW M engines come pretty much tweaked and tuned out of the box. The simple things that give Chevy motors power have been done in spades already, by German virgins wearing white linen & leather uniforms.

Using one metric, the V10 puts out 100 hp / l. Look at the Chevy LS7, 500 hp from 7 liters (71 hp / l). What work would you have to do to the LS7 to get 100 hp / l or 700 hp - all motor?
 

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I would think there would have to be some room for improvement. I know most OEM heads have a little bit of wiggle room simply because they are built for longevity, not 100% performance. I'd also love a good set of cams. Viper engines (I know it's not really a comparison, but it's the only other V10 I'm familiar with) can gain a good 50-100 HP from a good head job...but then can't we all lol! Somebody want to be the first?
 

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No improvement; the specs of the S85 heads are already very tight. BMW uses a gasket and does NOT recommend milling when doing head work.

BMW heads are already flow benched at the factory.

You have to understand that the s85 engine is cast at the SAME factory as BMW's F08 F1 car. Same people that make the M5 block make F1 blocks.

I dont think Dodge can say the same thing.
 

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It's not worth the gain to port the head on the M5, unless you are running some serious cams and boost.
Yes you are right. Without the cams, a ported head(even flow benched) wont give you the butt performance that you seek. I saw a dyno of an E30 M3, flow benched, and it only yielded plus 5whp:crying2:. On the other hand I saw a dyno in the same shop of an E30 with cams and a ported head and it producted around plus 25 whp. But some guys in Sweden have claimed to come out with 400 to 460 hp on a S38 engine on different levels of mods. It involves the usual cams, high comp pistons, ported head etc. Probably too radical to be DD though.
 

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Yes you are right. Without the cams, a ported head(even flow benched) wont give you the butt performance that you seek. I saw a dyno of an E30 M3, flow benched, and it only yielded plus 5whp:crying2:. On the other hand I saw a dyno in the same shop of an E30 with cams and a ported head and it producted around plus 25 whp. But some guys in Sweden have claimed to come out with 400 to 460 hp on a S38 engine on different levels of mods. It involves the usual cams, high comp pistons, ported head etc. Probably too radical to be DD though.
+1 :)
 

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Dude, I don't mean to pick apart your post, but:

I'm pretty sure that every OEM Mfgr. flow benchs their heads at some point, otherwise they wouldn't run.

Although it's pretty cool that the s85 engine is built at the same factory as the F1 cars, and the same people that make ours could be making the F1 blocks, I'm pretty sure that those same guys could be pretty proficient at making toasters. To me, just cause they are made at the same plant has almost nothing to do with them both being built to peak performance.

And, yeah, I'm pretty sure Dodge can't say the same thing. They don't do F1 but they do do other racing ventures.

I personally wouldn't buy a set of heads, or send mine off to be milled, unless we were squeezing 50+ HP at the wheels from these things. Besides, you and I and everybody else here all know that they would probably be like 15k plus a 10k core charge...not including cams.

E


No improvement; the specs of the S85 heads are already very tight. BMW uses a gasket and does NOT recommend milling when doing head work.

BMW heads are already flow benched at the factory.

You have to understand that the s85 engine is cast at the SAME factory as BMW's F08 F1 car. Same people that make the M5 block make F1 blocks.

I dont think Dodge can say the same thing.
 

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If you are talking about a simple port and polish job, I would think that this is already done with the BMW M5 heads.

Back in the day, when you removed the heads from a Chevy 350, the ports would be all bumpy and rough. Sometimes there was even ridges from the release of the cast in the combustion chamber. We would always take our heads and have a port job where every thing was polished to look like a mirror and flow tested to make sure they flowed well. That was in addition to all of the other work that we would have done with the heads. But this usually went with a new cam, higher compression pistons, bigger valves, etc.

When you take a BMW head from the E60 it already looks polished and really clean. I wouldn't think there would be much room to work with the heads, they are pretty much maxed out from the looks of it.
 

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I agree the M5 already has the heads max'ed out. I've run my finger in there on this motor and it was very smooth.
 

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If I had the head out for some other reason:dunno:, I would at the very least do a 3 angle valve job and de-shroud the valve area. Sounds simple but the rewards will be well worth it.

Paul
 

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If I had the head out for some other reason:dunno:, I would at the very least do a 3 angle valve job and de-shroud the valve area. Sounds simple but the rewards will be well worth it.

Paul
I can't imagine it helping a lot. If you look at the heads, the valve area is really clean, polished very well. The angles around the valves seats look like a professional aftermarket head job.

The only way to get these heads to flow a lot better is to change out the cams and/or valves for a more aggressive profile.
 

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I can't imagine it helping a lot. If you look at the heads, the valve area is really clean, polished very well. The angles around the valves seats look like a professional aftermarket head job.

The only way to get these heads to flow a lot better is to change out the cams and/or valves for a more aggressive profile.
I agree.
 

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Hey Gustav could you please find out if Hartge has any information on this subject of the M5 heads.
What I've heard is that they are pretty max'ed out.

Thank you for your help,

JUAN
 

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Hey, with the correct amount of $$$$$$$ it could be built even more...heads that breath more efficiently need an efficient intake also, dont'ch know !!
 

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Back to life !

I have been talking to a friend that works on high end builds, He told me that he did a P&P on a blue 07 E60 M5 bone stock. The car picked up 65.8 WHP with no mods just the P&P anyone on this ?


Work was done in NJ
 

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Back to life !

I have been talking to a friend that works on high end builds, He told me that he did a P&P on a blue 07 E60 M5 bone stock. The car picked up 65.8 WHP with no mods just the P&P anyone on this ?


Work was done in NJ
Yeah ... but maybe 6.58whp ...

Just impossible to make 65whp which is around 80 crank just from simple port and polish of extreme engineered , racing based engine .
Sorry but cant trust that !
 
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