M5 TB's on a M30 ?

[535ise]

Hi all :-)

Has any one got any ideas on putting M5 throtle bodies on a M30 535 E34 88'.

I know that theres a differance in port shapes between these two motors but i'm hoping to buy/make an intake manifold so that i can blend the differant shape/sizes between my head and the TB's ?

Which engine should i take theses parts from ? Or should i say which is the most suitable for this conversion ? E28 M5 or E34 M5 3.6 or 3.8 ?

Does any one have any picture's of any of the M5 TB's,manifold's or air box's ?

Anouther alternative i was thinking about is to make a custom intake manifold that uses a larger single TB that is routed so that it takes air from the alternator side of the radiator rather than going up and over the engine like standard.

I think i read some where that the US version of the E36 M3 had a large single TB around 100 mm bore ?

The modifications so far are....

Ported/flowed head and inlet manifold
Schrick cam and fitting kit(springs rockers etc)
Slightly over sized Valves( + 1 mm on the inlet's i think ?)
Stand alone custom 3D mapperble ECU
No AFM
Oil catch tank for the crank case fumes
After market sporty exhaust
4 inch bore air box inlet pipe

After these mods i was thinking that the next best step for more power was to improve the inlet side of things ?

Sorry for rabbiting on but i wanted to throw a few ideas up in the air too see what you guys think.

P.S. I like the new lay out of the forum :wink2:

Thank's a lot,

Andrew
The UK

[Jeff N.]

I think you'll find no easy way to get the M5 intake to fit. Port shape is VERY different - 2 valve vs. 4 valve per cylinder. Better just to get an entire M5 motor.

What schrick cam are you running?

Jeff
90 535i
US version
Metric Mechanic Sport head (ported, cam)

[535ise]

Thank's for you reply Jeff :wink2:

Schrick 284 from Korman's.

Do you rate those bored out Tb's you can get ?

Cheer's

Andrew

[winfred]

it depends on if you can make good use of the extra aiflow, most cars the afm or ams is the same size as the throttle body, at which point the throttle body could be twice the size and not flow any more air. i have a machinest buddy who bored out a m20 throttle body to accept a m30/50 butterfly, it's about 5mm larger(most overbore tb's are 2-3mm), i gutted a 535 afm and installed the electronics from a 325 afm and tweeked the spring tension for the smaller engine, i allready had headers, lightly ported intake, 19# injectors and a chip,

[535ise]

Hi Winfred,

I'll bet your E30 went well after those mod's

I've just sold my M30 AFM to an E30 325 owner who want's to do the same as you but in a slightly differant way.

Here's a picture of my engine bay (before i tidied up the wireing)


As i'm no longer restricted by an AFM,What's the best way to improve the the breathing on the inlet side ?

Bored TB and a panel air filter ?

I can get a bored TB for £ 120 (= $ 218)Alot cheaper than BMP wants for one !

Korman's do a inlet manifold that's meant for carb's but i'm sure i could get some TB's to fit it,but this option is going to be expensive as they want $ 400 just for the manifold.

Cheer's

Andrew

[Jeff N.]

Not sure I have any recommendations on your flow questions but I am curious about your ECU upgrade. Can you comment on what unit you used and what adjustment/tuning features it provides? I'm curious in ways that I can gain control over my fuel maps, advance maps etc.

Jeff
90 535i

[535ise]

Hi Jeff

The Ecu i use gives you total control over fueling and timing maps.It's fairly easy to fit and wire up your self.

It comes with a base map to get you going then you take it on a rolling road to get it optimized for your car.If the spec of your engine is similar to mine the base map you get supplied will probobly be the one from my ECU.

It's not cheap though £ 550 or $ 1000 in US money.I imagine the shipping wont be to much as it's not a very heavy item.

There is one thing that i've got to sort out though is a differant ICV as the standard one isn't compatible so when the engine is in the blue on the temp gauge it won't tick over properly.It's not expensive to fix it's just that i haven't got round to doing it yet.

You do lose your dash economy meter and range/consumption functions on your obc but as they weren't very accurate i don't miss them.

There web page http://emeraldm3d.com/

HTH

Andrew