No Hotrod Valves for M30...

[Robin-535im]

Just an FYI for anyone rebuilding an M30 head... So far I haven't been able to locate anything other than stock valves, called Korman, BMP, VAC, and visited with local "builders". Lots of choices for hotter springs and various cams available but no one sells lighter/stronger valves. Which is good I guess, says something about stock parts.

Local guy charges $44/$45 for exhaust/intake valves, and that was a "special" deal for me because he's such a nice guy. BMA has them for half that!

I'm thinking of cutting down the part of the valve guide that hangs into the throttle throat like a big brass tonsil. I don't suppose anyone has any experience with that? BMW usually does things for a reason I assume, so maybe it's needed for stability. The guy at Korman (not Ray, a guy in sales) was pretty confident it was just fine. Sure looks like a major obstruction in the airway though.

- Robin

[winfred]

ireland has 38 39 and 46 47 mm, depending on year some of those are upgrade sizes https://secure17.nexternal.com/shared/StoreFront/default.asp?CS=ireland&BusType=BtoC&Count1=281856715&Count2=198997139

[Bill R.]

lighter and stronger, depends on the pocketbook






Just an FYI for anyone rebuilding an M30 head... So far I haven't been able to locate anything other than stock valves, called Korman, BMP, VAC, and visited with local "builders". Lots of choices for hotter springs and various cams available but no one sells lighter/stronger valves. Which is good I guess, says something about stock parts.

Local guy charges $44/$45 for exhaust/intake valves, and that was a "special" deal for me because he's such a nice guy. BMA has them for half that!

I'm thinking of cutting down the part of the valve guide that hangs into the throttle throat like a big brass tonsil. I don't suppose anyone has any experience with that? BMW usually does things for a reason I assume, so maybe it's needed for stability. The guy at Korman (not Ray, a guy in sales) was pretty confident it was just fine. Sure looks like a major obstruction in the airway though.

- Robin

[BigKriss]

http://www.ferrea.com/

[Robin-535im]

lighter and stronger, depends on the pocketbook
I'm afraid to ask what they would cost... Sure look like more than a $23 part to me!

[bill g]

The M30 camshaft and inlet tract including the head ports are carefully designed to give good mid range torque and overall performance. It looks to me as if the port is shaped as it is to help guide the intake charge smoothly past the valve guide boss, which compared to many heads does not project much into the actual airstream.
I had my cylinder head ported by a professional who had done many of these heads. My aim was to make the thing work as well as possible without resorting to 'performance cams' and bigger valves and I particularly did not want to destroy the bottom end performance.
Hogging out the ports may help high rev performance but will surely stuff it up everywhere else.
The head guy did not remove lots of material from the head - the main object was to smooth the flow, remove sources of turbulence, and improve flow into the cylinders at low valve lifts. He did not touch the valve guide boss much at all and we reused the stock valves and springs, but with new valve guide inserts.
Anyway the result is about 12 to 15hp increase in max power but more importantly (to me) improved torque right throught the range. And it pulls very strongly all the way to 6800 rpm in the lower gears, with typical surge from about 3800.
I realize some of this improvement would be due to the fresh head irrespective of the porting, but the engine had only done 65000 miles so the head was pretty 'fresh' anyway.
Unless you plan to turn your M30 into a different kind of beast altogether and regularly drive in the rev range 6500 to 7000 plus I doubt you need bigger and lighter valves and all that stuff.

Bill G Melbourne Australia

[Robin-535im]

The M30 camshaft and inlet tract including the head ports are carefully designed to give good mid range torque and overall performance. It looks to me as if the port is shaped as it is to help guide the intake charge smoothly past the valve guide boss, which compared to many heads does not project much into the actual airstream.
...
Unless you plan to turn your M30 into a different kind of beast altogether and regularly drive in the rev range 6500 to 7000 plus I doubt you need bigger and lighter valves and all that stuff.

Bill G Melbourne Australia

I agree 100%. I tend to have faith in the design team at BMW, even if the shade tree hot rod in me has different ideas. I plan to use the stock valves, and maybe new stock springs or new HD springs, with a Schrick 284.

Jeff N and I discussed this last week. I could imagine low-flow velocity & low end torque could suffer if the inlet was too free flowing, especially if there is a point in the flow where it slows due to an enlarged area.

My secret plans for this beast include m5 throttle bodies & headers, which are already on the way from Germany. Probably I'll end up screwing it all up and will have cool throttle bodies with terrible flow! :) Still not sure about hogging out the guides with the tb's... Definitely will take your experience under consideration...

[Jeff N.]

Robin - BTW, I may have some answers forthcoming on the tuning problems I related on the phone. I'm arranging a meet-up with Dan Miller from Miller Performance to see what they may be able to do. Spoke with them on the phone and they seem be pretty interesting, smart guys who can tackle the problem.



I agree 100%. I tend to have faith in the design team at BMW, even if the shade tree hot rod in me has different ideas. I plan to use the stock valves, and maybe new stock springs or new HD springs, with a Schrick 284.

Jeff N and I discussed this last week. I could imagine low-flow velocity & low end torque could suffer if the inlet was too free flowing, especially if there is a point in the flow where it slows due to an enlarged area.

My secret plans for this beast include m5 throttle bodies & headers, which are already on the way from Germany. Probably I'll end up screwing it all up and will have cool throttle bodies with terrible flow! :) Still not sure about hogging out the guides with the tb's... Definitely will take your experience under consideration...

[Jeff N.]

.

I'm afraid to ask what they would cost... Sure look like more than a $23 part to me!

[535ise]

Which M5 TB's, E28 or E34 ? Diameter of the throttles ? Which type of ECU and cam are you using ?

How are you mounting them to the head ?

I started a similar project with some E28 M5 TB's on my M30 but gave up on it inplace for some thing simpler(see pic below), a friend who is more dedicated to seeing the project done had them off me for his E30 335 turbo.

He ended up having to chop one of the pipe stubs from the 'stat housing and use an angled/bent bit of tubing from another car to clear the TB's. You should be OK on the E34 chasis but he had to move the brake servo over, use a smaller servo and had to cut/weld a bit of the plenum to fit. Plus some other stuff needed doing to get them to work, a PITA in other words.

Good luck with the project, i hope it goes well for you.

(still not fitted properly yet, twin 60mm TB)

http://img174.imageshack.us/img174/2104/picture041rrzc8.jpg

[Robin-535im]

Which M5 TB's, E28 or E34 ? Diameter of the throttles ? Which type of ECU and cam are you using ?

How are you mounting them to the head ?

...a friend who is more dedicated to seeing the project done had them off me for his E30 335 turbo.

... a PITA in other words.

Good luck with the project, i hope it goes well for you.
...

Right now I'm still in the planning stage so I may decide it's indeed too much work, but I've got some e34 M5 (S38B36) throttle bodies on the way from Germany, (assuming the seller keeps up his end of the bargain.) I'll use the same ECU and some sort of alternative to the AFM, like a MAP or MAF. Idle control should be pretty much the same, as should TPS. Clearing them in there and mounting it up is where the costs come in, and my plan is to saw off the last inch of the stock manifold, saw off the last inch of the TB's, and weld them together. That way I keep the bolt pattern and injector geometry to match the head. Now will that really work? I have to get the parts in hand to really see.

I've seen the thread on the e30 board, that is an impressive setup. Hopefully the air box won't need a hunk cut out for the e34!

The head I'm still building up, and I plan to get a Schrick 284 cam from VAC and keep it otherwise stock. It's been CNC ported by Bavarian Engine Exchange and it looks pretty well done, but I am by no means an expert. I may totally screw up the whole engine and have less power than stock but it's worth a shot just for the gleaming TB's under the hood. The headers have the same plan, I've got s38B36 headers and will lop off the last inch and weld on a flange that matches the M30 head, then fab a piece to make the bottom bolt on to the rest of the exhaust.

The MAF/MAP should allow me to get the mixture right, and if I want to play with timing that's another $500 or so for a programmable ECU... I'll wait on that until the beast proves it can make it down the block!

[535ise]

I'll use the same ECU and some sort of alternative to the AFM, like a MAP or MAF. Idle control should be pretty much the same, as should TPS.

Yeah, i think you need to lose the stock AFM if possible, some thing(ECU) that allows you to tweak the fueling would be good ?


Clearing them in there and mounting it up is where the costs come in, and my plan is to saw off the last inch of the stock manifold, saw off the last inch of the TB's, and weld them together. That way I keep the bolt pattern and injector geometry to match the head. Now will that really work? I have to get the parts in hand to really see.

Given the chance again i'd be cutting/welding the mounting flanges rather than mess about with an adapter plate. I'd cut the M30 manifolds just upstream from the injector boss's.



I've seen the thread on the e30 board, that is an impressive setup. Hopefully the air box won't need a hunk cut out for the e34!

Yeah, you should have more room to play with, i've not been in my freinds 335T since the TB's went on but he is happy with them, it was a very rapid before the TB's(330RWHP), he is maxing out his 30lb injectors on a fairly low boost level once he gets that sorted the boost is going higher i think.



The head I'm still building up, and I plan to get a Schrick 284 cam from VAC and keep it otherwise stock. It's been CNC ported by Bavarian Engine Exchange and it looks pretty well done, but I am by no means an expert. I may totally screw up the whole engine and have less power than stock but it's worth a shot just for the gleaming TB's under the hood. The headers have the same plan, I've got s38B36 headers and will lop off the last inch and weld on a flange that matches the M30 head, then fab a piece to make the bottom bolt on to the rest of the exhaust.

Sounds a nice set up you are aiming for, i'd like some headers my self but RHD isn't too helpful, i bought some 'pina B10 headers because they were cheap but there was no way they were going to fit with out buchering them.

I've got my head ported and a 284 schrick but i don't feel that it pulls hard enough over 5.7k rpm so my hope is the twin TB will help flow more air to help this ? I know the M30 is no rev monster but i'm hoping it will make peak power around 6.2k rpm ?



The MAF/MAP should allow me to get the mixture right, and if I want to play with timing that's another $500 or so for a programmable ECU... I'll wait on that until the beast proves it can make it down the block!

Some thing like MS is the way forward modded engines/owners that like to tweak and/or keep modding. Once my TB is on my Emerald ECU is going to get remapped.