Touring turbo

[S4Driver]

M50B25 Vanos pistons to M20B25 turbo. Are they any good?. Stronger than originals? Do they need machining from top?

M20B25 turbo
options


M50B25 Vanos pistons+orig.rods
Orig pistons and rods, burned a hole allready, with Motronic. Stupid me.
So not an option.
M50B25 pistons+M50B25 nonVanos rods, 135mm
M50B25 Vanos pistons and rods, 140mm. Do they fit, what happens to comp.
Forged custom pistom +0,5mm overbore+Eagle rods
Last one is strongest but will cost alot.
Tatech for brains.
Hope you understand my purpose.

[Colonel Sanders]

vanos pistons will work with stock rods, giving a cr around 7.5, unless your going real high boost i wouldnt bother, if i were you get stock m20b25 pistons and get the squish shaved off the top and new valve reses cut out, and your good to go with 8.0 cr, and can handle 500hp daily with good tuning.

[S4Driver]

So its vanos pistons+orig rods. How much boost they could handle?

[Colonel Sanders]

its all about the tuning, if you can get it right or have someone do it for you, (like i have had to) maye over 1.5BAR.
but with the lower CR i would still say standard pistons for the tad higher CR = more power at less boost.

[Gunni]

stock everything in a non vanos engine + MLS gasket = 550hp at least.

[S4Driver]

So my original pistons are totally fucked up. So have to replace them.
I have M50 non vanos rods and vanos pistons. Think im gonna put them in.
1,5bar-?
Have in place 390cc injectors. Bigger ones? 450cc-500cc?

[Gunni]

what ecu are you using?

[S4Driver]

Tatech engine management system, Lite version. Easier to use, because it has been made here in Finland, language.
Tatech.fi also in eng vers.

[S4Driver]

In earlier version car ran with original motronic and bigger Garret turbo, 369Hp/510Nm with 1.0bar of boost, original internals. Ringed top, shaved pistons.
Now i have installed a little smaller Holset HX35 so it wakes up earlier.
I have stripped my car to bare shell, only racing seats. So its fearly light.
Tryin to get it to 3kg/1Hp. Would be fun to drive.
Before it broked down little testing with 0,5 bar but i run out of numbers at speedo.
6400rpm/240kmh, it pulled to 7000rpm limiter easy.
It a touring, looks like crap but goes like mad. No rust at all.
Hope when i get it fixed some videos will be posted.

[S4Driver]

Forged diesel crank 81mm stroke, M20B20 rods 130mm, M50B25 vanos pistons or orig. pistons? With 135mm rod comp too high?
Have collected 130mm, 135mm and 140mm rods. M5025 vanos and non-vanos and orig pistons.
Goal is lower comp more boost. 7-8:1, 1,2-1,5bar.
Any ideas?
If i have bore oversize, then its forged pistons with 135mm M52B28 rods.
Hope not, money, money. Never enough of that thing.

[Gunni]

you could go with 2,7crank, b20/eta rods, eta pistons and 885 head.

325i pistons just lower the compression so much.
Try and get your hand on M70 pistons and compare

[S4Driver]

Just bought ETA crank. Goin to stroke the thing.

Tryin to calculate comp.

piston 83,99mm
stroke 81mm
gasget thicknes without compression 2,05mm. compressed? any idea?
gasget diameter (hole for piston) 84mm? or is it bigger?
head of the piston is flat
piston not level with block deck, 3,25mm lower
head 43cc, pistons do not make this space smaller

Got 7,20:1 NICE LOW COMP FOR HIGH BOOST
Block deck had been skimmed, dont know how much. Gonna skim the head, just to make it straight.
Skimming and headgasget compression will rise it a bit, but not much.

Am i totally lost, or does this make any sense?

Pistons are lower than original M20B25 pistons (KH34,2mm)
Mine are M50B25 vanos (KH 32,55)
M20B20 130mm rods
Holset HX35
o-ringed block
BIG cooler
injectors now 390>should go to aprox 500-560?
Tatech Lite version
Boost ??? 1,5>up

[S4Driver]

84,5mm forged special JE-pistons, ARP bolt set, Motornord 135mm rods, Haltec ems.
Need also bigger inj. Gonna get 650cc.
Progress atlast.

[S4Driver]

New goodies for blown engine:

-JE-pistons 8,5:1 comp 84,5mm witch have:
-Total-Seal Gapless Top rings (Endurance Road Race, Extreme Turbo and NOS Use.)
-High Heat Ceramic Coated crowns and Moly coated skirts
-Double Pin Oilers
-Motornord 135mm rods
-New bearings OEM, gasgets
-ETA 81mm crank
-AMC factory new head
-Motec M600
-Motec CDI-800
-Mercury coils
-ARP bolts, all
-New Holset HX52 67/70 , exh size 11
-Adapter T3>T4 Holset
-Downpipe 3,5", modded Viper pipe with v-bands
-Big wastegate
-Screamerpipe
-O-ringed block
-Modded OEM headgasget 2,05mm
-New racevalves, +1mm, PPF
-6 new Delphi 998cc/h injectors . Size standard Bosch 75mm.
-Inline-Walbro 255lx2.
-Intank-Carter 400l/min feeds the Walbros
-IE HD rockers, PPF
-M20 stödgördelkit (ARP) PPF, bottom plate that keeps the block straight when revved hard>8000rpm
-Fuellines 1/2"/9,5mm
-Nuke Performance filter, PPF
-Nuke Performance fuelrail, PPF
-Nuke Performance y-connection, PPF
-Nuke Performance cam gear, PPF
-M20 Z58 cam, 296, 12,3 lift, PPF
-M20 steg 3 valvesprig set, PPF
-Diesel oilpump, new
-For head, all parts new
-VEMS egt+wideband
-MSD 8.5mm wires
-Lightened flywheel
-Balanced
-Light headwork

-Bigger cooler? 620x310x120
-Bigger coolerpipes? 3"

-First e36 M3 ZF, when it fails then
-TREMEC TKO 600

-V-Power/E85



-Borbet T 7,5x16 205/45
-Lots of tyres, different condition 225/45/16, for fun
-Toyo R888/slicks
-H&R arb:s
-Wiechers swaybars for back, up and bottom
-60mm lowering
-Supersport short shocks
-3mm plex windows, not windshield
-Rollcage
-Classfiber bonnet with big EVO scoop
-Powerflex allround
-New controlarms
-Digital gauge
-Roof scoop
-Hartge swaybar
-Goodridge brakelines with stainles connectors
-Bigger brakes allround, Porsche

Opinions please. Pics when engine is redy.

[Gunni]

If you don´t break

What ignition setup are you going to run?
You should be needing a MSD box for the power level you´ll be running at.

[S4Driver]

-Motec CDI-800
-Mercury coils


Good for over 2,4bar

[Gunni]

Ah I missed that ;)