BMW E30 Flow Figures

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GazTwo
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Post Mon Jun 11, 2007 8:23 pm

Bit of a random post as I haven't been on here in a long time but just incase anybody's interested....

Not so much Turbo or Super Charger but wasn't sure which forum would be best.

Anyhow as above Steve @ Port-Formance has just finished an E30 320I (12valve) head with some excellent gains... 8)

Also installed was a Piper 270 Cam which gives around a 10.4mm lift from memory, so at 10.5mm lift the head (on it's own) is producing a 31bhp increase from standard... :D

Car needs to be put on the rollers to make sure the fueling is correct so I'll give an update on the power figure once it's been done, customer was VERY happy when he collected the car last night... :)

Flow graph.....

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Post Tue Jun 12, 2007 1:32 am

31 BHP gain on a 320? No wonder the guy was happy!
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Post Tue Jun 12, 2007 12:56 pm

31hp from a flowed head and cam, that's some good going :cool:
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Post Tue Jun 12, 2007 1:07 pm

and how much did it cost him...would it have been better value to put a 2.5 in?
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Post Tue Jun 12, 2007 1:58 pm

it looks like the bhp gains are estimated from the increase in flow bench numbers? but unfortunately it doesn't work that way.......you'll need a dyno for hp
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Post Tue Jun 12, 2007 2:24 pm

I was thinking that /\ as the OP mentions it needs to go on the rollers. Would have been nice to see a before and after on the same rollers. :thumb:
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Post Tue Jun 12, 2007 5:58 pm

The cost for a 12 valve head to be flowed is £600, thats purely just porting and flowing. The guy wanted to keep the car original as his Dad purchased the car brand new and he has just recently bought it back from the owner his Dad sold it to.

Yes the bhp figures are from the flow figures so are just giving u a bhp increase for the head.

I would think it'll be producing a healthy bhp and torque figure once it's been on a rr.... :cool:
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Post Wed Jun 13, 2007 2:18 pm

GazTwo wrote:The cost for a 12 valve head to be flowed is £600, thats purely just porting and flowing. The guy wanted to keep the car original as his Dad purchased the car brand new and he has just recently bought it back from the owner his Dad sold it to.

Yes the bhp figures are from the flow figures so are just giving u a bhp increase for the head.

I would think it'll be producing a healthy bhp and torque figure once it's been on a rr.... :cool:
problem with that is

1) the cam isn't always at full lift. In effect you need the weighted average lift which is a better measure but difficult to determine
2) the head is not the only component in the system.

As for the actual bhp increase i would not expect more than 5-10% the m20 heads (atleast 885) don't flow too bad, sure it won't do much after 6-6.5k but plenty of midrange (usable power) is available
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Post Sat Jun 16, 2007 6:33 pm

"those that can - do, those that can't - critisise" what else you gonna use to test it with YOUR FINGER!!
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Post Sun Jun 17, 2007 1:51 am

nothing wrong with quoting flow numbers if you know what they mean........ but bhp from head flow numbers don't mean a thing and it goes against the definition of the actual acronym, so there is no use pretending otherwise and spreading misinformation or unrealistic expectations.
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Post Sun Jun 17, 2007 8:17 am

m20b20 ports are big enough already.. Expect a nice loss of bottom end and mid range imo due to gas speeds
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Post Sun Jun 17, 2007 1:57 pm

Gentlemen, couldn't help but stick my two peneth in , as your talking about my Dad's BM..

As mentioned, my Dad bought this car from new in 1990, he adored it, he kept it for around 6 years and then replaced it with a new E36 (some would say, why?), he passed away in 2003 and it took me a while to get it back, but I did, long story but for another thread..

I'd like to keep the car as close to how he bought it, hence the original engine stays and a swaps not an option. I plan on spending the next few years turning this car into a show piece.. I'll show my progress on E30 Zone

As far as commenting on the results of Port-Formance's head work, all I can say is "the proof is in the pudding". It's definitely done something right, it's made a massive difference, honestly a massive difference, it feels like a completely different car.

From stationary you can feel a marked difference, but when it gets to around 3500 revs, wow, he has turned my car into an absolute belter..

Anyone considering flowing your E30 head, can't recommend it enough.

Thank you Port-Formance..
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Post Sun Jun 17, 2007 2:33 pm

Too much willy waving on here of late

so what if the car in question is a B20 engine, having the B25 is not the be-all and end all of e30 ownership, certainly the smaller six has its benifits.

be nice too see a dyno to back the figures up, not because I'm a doubter, merely beacuse then the relaitionship between the flowbench figures and the "real world " can be assesed fully

Stuff like this benifits us all in the modding scene, so from me at least, some applause for trying something new

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Post Thu Jun 21, 2007 7:58 pm

With over twenty thousand flow tests I've a rough idea of what to expect a head to do once it's refitted back on the engine and my experience tells me the flow bench isn't far off the mark when it comes to predicting power increases, as soon as the cars been on the rollers I'll post the graph but the flow bench is an industry standard measuring device which allows hundreds of tests on a head without refitting it to the engine, the BM head in question visited the flow bench around 70 times to find those increases and it gets right on my nipples when students waffle on about things they no nothing about, these are accurate, repeatable figures that I base my reputation on and have been doing for the last ten years —a anyone got any better figures? I think not!!

I imagine when the Dyno graph is posted people will say the rollers read high —a can't win.

p.s. does anyone know what the car produced from the factory?
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Post Thu Jun 21, 2007 8:06 pm

130bhp iirc
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Post Fri Jun 22, 2007 11:33 am

port-formance wrote:With over twenty thousand flow tests I've a rough idea of what to expect a head to do once it's refitted back on the engine and my experience tells me the flow bench isn't far off the mark when it comes to predicting power increases, as soon as the cars been on the rollers I'll post the graph but the flow bench is an industry standard measuring device which allows hundreds of tests on a head without refitting it to the engine, the BM head in question visited the flow bench around 70 times to find those increases and it gets right on my nipples when students waffle on about things they no nothing about, these are accurate, repeatable figures that I base my reputation on and have been doing for the last ten years —a anyone got any better figures? I think not!!

I imagine when the Dyno graph is posted people will say the rollers read high —a can't win.

p.s. does anyone know what the car produced from the factory?
if your engine is sucking through a straw then 14% flow increase on the head won't yield 14% gain in power because the head is only one part of the system, sure it may yield 14% with a whole heap of other mods that compliment the head . Its hard enough to get reliable hp numbers from a dyno let alone from the head flow by itself, i know customers like to know what hp the flow work will net but thats what the dyno's is for.
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Post Sun Jun 24, 2007 8:37 pm

The reason for putting the BHP figure on the graph is because few if any customers know what CFM figures mean and how it relates to their engine, the graph posted has all the information on it you could ever wish for as a potential customer for a flowed head yet some people will still blow money on a stage 3 big valve head without knowing anything more about it.

wise up, no flow figures no sale, you wouldn't buy tyres without knowing the sizes regardless of how cheap they were.

For ten years I've been giving customers these graphs to show where the head started, where it's ended up and the percentage difference between, what I didn't realise is how few customers understood fully the work that was involved and increases they had gained by a percentage line only, how can more information on anything be a bad thing?
All heads are checked using the same back-to-back method and adaptors so years from now I can reproduce the increases you see above.
A back-to-back rolling road figure would have been useless in this case as the original cam and followers were showing signs of wear and most of my custom comes from engines that have blown the head gasket or some other reason for taking the head off, rolling roads allow a lot of movement in the figures they produce and all read different from each other unlike flow benches which have far less scope to â€Ëafudge' figures, I prefer not to convert figures from 10â€a of vacuum into what the yanks like to see which is CFM at 28â€a which most UK tuners seem to have adopted, what you see is unmolested data taken straight from the flow bench.

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Post Mon Jun 25, 2007 3:00 am

stick it on a well known rolling road n see how it gets on.. i know only a bench dyno is accurate, however people will know roughly where the figures stand relative with others..

flow figures are fair enough, but not everything
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Post Thu Jun 28, 2007 4:13 pm


It’s not luck!! with over 20,000 flow tests on heads it’s commitment & damned hard work - DO NOT COME ON & TELL ME HOW TO DO MY JOB from what you've read...
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Post Thu Jun 28, 2007 4:31 pm

A healthy early 2.5 should be around 170bhp @ the crank, a facelift model somewhere around 160/165bhp.

A early engine on late management should see 170+bhp.

I'd be VERY interested to see what you can do with a 2.5 head as the only supplier of these in a tuned form is FRITZ BITZ who offer stage 1 to 4 IIRC.

Having gone from a shagged head with worn rockers and really worn cam to a new head, followers and cam I can imagine the effect the porting has, I can say hand on heart the difference is very noticeable. ( Plus it's sooo quiet too!)

How much do your services cost? and do you do head welding?

HTH, Mark.
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Post Thu Jun 28, 2007 5:00 pm

Hi Mark
Prices are £50 per valve for flow work, all supplied with before & after flow graphs specific to that head, all manner of repairs to heads are available from guides, skims, seat re-cutting, welding & broken stud removal. Obviously prices depend entirely on inspection.
It’s not luck!! with over 20,000 flow tests on heads it’s commitment & damned hard work - DO NOT COME ON & TELL ME HOW TO DO MY JOB from what you've read...
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Post Thu Jun 28, 2007 8:46 pm

When porting a head is it worth doing the exhaust side ?
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Post Fri Jun 29, 2007 11:04 am


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Post Tue Jul 03, 2007 2:07 pm

The good thing about headwork (when done properly) is the gains are everywhere from turning the key and it starting easier to bouncing off the rev limiter, with more torque and a willingness to rev as well as better fuel economy, there really are no pitfalls when air speed is increased due to a better port shape “massagedâ€a into the original design, unfortunately most tuners just make the ports bigger thinking that it MUST flow more now it's bigger & shiny (where jhonno got mixed up with a loss in mid range).

In 1997 I set off in a different direction to “stroke the cat backwardsâ€a working out how vacuum transfers from the cylinder into the port (not something that can be seen or imagined) all this rubbish about â€Ëafluid flow' means nothing when it comes to vacuum transfer & gas speed through an engine, testing small changes constantly has sent me off on an unorthodox route to the norm' with equally revolutionary increases previously unseen from headwork, I have seen what other tuners call good & quite frankly I wouldn't let them tune a radio - let alone an engine.

Forget everything that's gone before when it comes to headwork - this works and it works better than you could imagine, the most important person in all of this has got to be the customer because he's the one that spent his hard earned cash on the modification —a and guess what “he's over the moon with the resultâ€a all the criticism and hair splitting riggid wants to add won't change Royalblu's opinion of how it feels or weather it was worth it.

Surely all businesses want happy customers?
It’s not luck!! with over 20,000 flow tests on heads it’s commitment & damned hard work - DO NOT COME ON & TELL ME HOW TO DO MY JOB from what you've read...
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Post Tue Jul 03, 2007 2:18 pm

Would still be interesting to see back to back engine dyno figures for the standard head and modified.

Would certainly silence the critics :)
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Post Fri Jul 06, 2007 2:01 pm


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Post Fri Jul 06, 2007 5:36 pm

You've been very quiet for a few days RIGGID (you been for a â€Ëadump'). I don't specialise in any one make of engine and when I do get involved with one it always causes controversy due to the increases I seem to get compared to other (vehicle specific) tuners.

I specialise in flowing heads on a flow bench to get as much performance increase as I can find at the time of testing, years from now I may well beat my own figures as porting is a constant apprenticeship with little tweaks popping up every now & then that work on some heads but not others (but you have to try them anyway) which is how I've got to this point in time by chipping away slowly on other port designs to see what works and what doesn't testing constantly every little change.


PORT-PORMANCE STATEMENT; Nobody (Globally) tests as much as I do when flowing a head to extract as much power gain as possible! I'm not saying I'm the best head tuner in the world - just the one that tests the most…..and misses the least.

For this reason I know my figures frighten people, never has so much information been offered to a customer for a service of this kind, most heads are sold as a â€Ëastage' head with no more information available than that, I've tested other tuners big valve stage 3 heads and been able to wipe the floor with mine on stock valves time & time again.

How many times do I have to beat other tuners heads before I realise I've found something others have missed due to the amount I test, you'd be pretty dubious of a workman that didn't use a tape measure or spirit level to do a job even though they may well have done the job before a 100 times, experience comes from testing not thinking!

The best thing would be to wait until the car has been on the rollers and produced a figure people can comment on, I welcome constructive criticism or questions but a pessimistic jerk in the corner does no good for anyone.

No offence intended
It’s not luck!! with over 20,000 flow tests on heads it’s commitment & damned hard work - DO NOT COME ON & TELL ME HOW TO DO MY JOB from what you've read...
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Post Sat Jul 07, 2007 4:49 am

port-formance wrote:You've been very quiet for a few days RIGGID (you been for a â€Ëadump'). I don't specialise in any one make of engine and when I do get involved with one it always causes controversy due to the increases I seem to get compared to other (vehicle specific) tuners.

I specialise in flowing heads on a flow bench to get as much performance increase as I can find at the time of testing, years from now I may well beat my own figures as porting is a constant apprenticeship with little tweaks popping up every now & then that work on some heads but not others (but you have to try them anyway) which is how I've got to this point in time by chipping away slowly on other port designs to see what works and what doesn't testing constantly every little change.


PORT-PORMANCE STATEMENT; Nobody (Globally) tests as much as I do when flowing a head to extract as much power gain as possible! I'm not saying I'm the best head tuner in the world - just the one that tests the most…..and misses the least.

For this reason I know my figures frighten people, never has so much information been offered to a customer for a service of this kind, most heads are sold as a â€Ëastage' head with no more information available than that, I've tested other tuners big valve stage 3 heads and been able to wipe the floor with mine on stock valves time & time again.

How many times do I have to beat other tuners heads before I realise I've found something others have missed due to the amount I test, you'd be pretty dubious of a workman that didn't use a tape measure or spirit level to do a job even though they may well have done the job before a 100 times, experience comes from testing not thinking!

The best thing would be to wait until the car has been on the rollers and produced a figure people can comment on, I welcome constructive criticism or questions but a pessimistic jerk in the corner does no good for anyone.

No offence intended
say what you will, make all the personal comments you wish and be as sarcastic as you want, you've more to lose than me.............

most tuners don't bother with the 200 casting anyway while it can improved alot the 885 is still a better bit of gear and there actually are other tuners who have tested 1000's of the exact same casting and have posted their flow data online if you look hard enough so you aren't doing something that none else does and the flow gains (exluding hp predictions) are not frightening at all, i don't doubt them one bit and i never have.....

you may indeed like you say get the most flow out of the head but you haven't convinced anyone here of the magnitiude of the real power gains.... only the flow increases that are possible, and the two aren't as directly related as you seem to think........... for instance using 'back of the envelope calcs' you claim a 31hp improvement on a 125bhp engine (25% more) from a port job that increased the flow a maximum of 14% at full lift which kinda suggest that the engine won't see all of the head gains claimed. similarly the hp gains are dependant on the other engine components which have not been factored into the head flow results.
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Post Sun Jul 08, 2007 8:11 pm

I'm sorry RIGGID if I offended you but as I stated â€Ëanone intended'. The graph posted wasn't by myself if you remember but by another customer of mine who has a Clio Williams running one of my stock valve flowed heads, a four branch exhaust manifold, K&N and Kent RN2002 cams, his engine is pushing 198bhp @ the flywheel and his involvement with the Williams owners club and tuners associated in that field have taught him other tuners can't get close with wilder cams and big valves, cars producing more power than his need throttle bodies to do it.
He thought e30zone members might be interested in seeing the graph I produced for Royalblu's head.
The flow bench produces accurate CFM figures to be scrutinised and from that a BHP value can be calculated, how you want to read that calculation is entirely your choice but what everyone who's commented so far seems to have missed is the information it highlights, everyone knows aftermarket cams produce more power yet opening the valve to a higher lift on a standard head doesn't produce more flow so gains come from longer duration rather than flow, the head now flows more air than a stupidly mad cam would produce giving customers an idea of what a good flowing head would do for their engine. CFM directly relates to power so an increase in CFM (should, could, would, choose which word applies to you) produce more power even if nothing else on the engine has changed.

Manufactures choose a cam profile to suite the desired characteristic required for a road car which is restricted by the port design/casting imperfections, my job is to then remove/reduce those restrictions and promote air flow increasing performance in the process along with fuel economy.

The problem seems to have risen when someone takes those calculations as law and wants to argue till they are blue in the face just for the sake of not being quiet, if you'd have asked me where those figures come from or how they relate to the engine I would have been happy to oblige! instead you set off to try and make yourself look clever (which you may well be in your own field but on this occasion you've failed miserably) headwork is a very very misunderstood subject which I'd like to say I've set out to educate people over or at least give them more information so they can make up their own minds on what's available.
I'd be very interested to see other tuners figures as I can't find them myself unless I'm looking in the wrong place? and as for doing myself damage with this banter “I think notâ€a as I've already had some strong enquiries from the flow graph posted for a range of different vehicles.

“Don't make enemies out of strangers as you'll have enough amongst the people you already knowâ€a

No offence!
It’s not luck!! with over 20,000 flow tests on heads it’s commitment & damned hard work - DO NOT COME ON & TELL ME HOW TO DO MY JOB from what you've read...
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Post Mon Jul 09, 2007 11:06 am


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Post Mon Jul 09, 2007 4:23 pm

RIGGID, you must first understand how many people out there are doing heads that have absolutely no idea how much damage they are doing to flow, over the years it's become apparent from using wind tunnels to develop car body shapes what design causes the least drag coefficient, given pointers the general public can see what shape is going to work well and what shape will fall flat when it comes to cutting through the air stream, if only as much research had been given to port design - Turbos wouldn't have needed to be invented, I'm amazed how many bad designs manufactures still use when all we hear about is efficiency and how to conserve fuel.

Imagine a car with a bill board on the roof and straight away you'd realise it wasn't going to be very efficient at all, that's more or less what some tuners are doing to the inside of an engine —a going backwards! The flow bench is a miniature wind tunnel but it works with vacuum at a set resistance (I use 10â€a) to pull air through a port and give a reading, at 10â€a on pump fuel every cubic foot of air is worth 0.43 HP, once that figure is known power output can be calculated accurately.

As you pointed out RIGGID the head is only one part of the equation but it's the most important and usually the only piece of the jigsaw I have to go on when a head arrives in a box, the flow data supplied applies to that item as a stand alone part, what the customer then bolts to it or uses it for is their business.

What you must understand is how personal I take a â€Ëadig' (or a comment that looks like a dig) when I've spent ten years researching this subject, but don't worry I spoken to â€Ëatop' design engineers that are clueless about the subject usually face to face though which allows me to explain my findings in more detail.

Sceptics are welcome, just choose the angle of attack more carefully when it involves artistic value!
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Post Mon Jul 09, 2007 5:18 pm

If you've got the facilities to do it Port-Formance, could you not engine dyno a stock engine, flow test the head, work your magic on the head, flow test it again to show the gains, and then rebuild it onto the engine for another dyno run.

It would stop all the conjecture and subsequent hassle that's invariably attached to these type of threads.

Incidentally, purposely miss-spelling someone's name's a bit low isn't it?
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Post Mon Jul 09, 2007 9:01 pm

What seems to be missed here is that flow testing is only good for stationary objects.

Putting a valve at full lift and then raising air flow trough porting will not make max air flow,
as the valves aren´t stationary ever when beeing opened and closed, only close until open, and that is also a really short time.

The best port job would come from measuring air flow on a engine dyno, re port the head, re install and re measure.
as in the real world both sides of the head determine air flow trough the intake ports. Also headers and intake design,

all this can be done on a virtual fluid dynamics simulator, but the cheapest way opviously is the hard way as well.
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Post Tue Jul 10, 2007 9:45 am

To be fair the places i have spoken to re head stuff the ones who are happy to supple figures and graphs all claimed from ther flow figures the resulting bhp is normally an accurate estimate give or take couple %. I am surpised not many e30 heads been flowed in the past so this is sort of a grey area to compare heads.
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Post Tue Jul 10, 2007 10:12 am

port-formance wrote: What you must understand is how personal I take a â€Ëadig' (or a comment that looks like a dig) when I've spent ten years researching this subject, but don't worry I spoken to â€Ëatop' design engineers that are clueless about the subject usually face to face though which allows me to explain my findings in more detail.
i am sure you didn't make the flow software or calculator or whatever was used to make the bhp estimates so its not meant to be personal, btw since i never asked how were the bhp numbers obtained. Nobody said the port job was bad or the results will be bad so it was never personal. If i was on the same continent i would come and have a look at your work and dicuss your findings further.