M20 B3x Naturally Aspirated Stroker build past, present and future

[leez]

Any updates for us digger

[skarlqvist]

If you want to run classic wheels and a big brake kit. K-sport is a nice alternative. This kit has 3 piston callipers and 350mm rotors. I have tested it to work with all the 18" wheels I like.
Order a 325mm rotor and it will clear 17" also.

[litu]

Nam nam

[skarlqvist]

A proposal for the ultimate screamer:
Move to dry sump, Use a 2.5l crank, Port the head, Bore the cylinders from 80 to 87mm, Use hi-comp pistons 12:1, Use RHD itb and roller kit with 316 cam.
Add a really light fly wheel and clutch pack and rev this 2,7l m20 to 10K.
This will give you more than 300whp at piston speed 25m/s and with the right exhaust a sound like a Honda CBX1000 ;-)

[litu]

It is all about the total package head. This awd dyno result is from my m20 low comp na stroker build. It pulls harder than an original s54. With a bigger cam there is a lot more to gain.

Wow, that engine in ix. We want more, way more info...Is there any where i can follow this project

[skarlqvist]

280 whp in an ix on a awd dyno with perhaps 15% drive train loss is a dead race against an original S54 (tested on the same dyno).
There is room for an additional horses if you go for the 302/309/316 roller cams (street-ability will suffer, this is none vanos engines).
The RHD roller setup allows for revving to 10K but the 89,6mm crank in my car translates to a pistonspeed of 25m/s at 8400 rpm.
Piston speeds of 25m/s is the upper limit in most engines.
The original m20 oil pump will start to cavitate at 8000+ so the real max rpm is actually 8000 (one must move to dry-sump for higher revs).
My engine is build for boost and >500Whp. If I was to keep it na I would have gone for RHD itbs, any day.
I have been talking to DBilas and they have pressure tested the plenum and itb construction for 2 bar.
For this car I have bought an Australian "Raptor V" supercharger and since the ix front diff is the weakest part I will limit power to 500whp on pump gas.
The engine needs a lot of air in and out. I use AEM Dry flow 76/135mm and the custom build 2x2,5" exhaust below.

[digger]

~240whp (281bhp) seems about right for that, though i would expect it to peak at higher rpm with the short runner dbilas intake but this might be a lazy dyno tech not setting up rpm correctly. Personally i would consider the RHD inlet it is far superior perhaps except for the OEM looks or lack thereof

[hasa]

Thats better than what I'd expect for standard compression and 173CFM head! Nice packet.

[skarlqvist]

ACSchnitzer S3 IXT with VW T5 Ronal wheels, Original M3 fenders with rework for read doors and handles.
E36 compact hubs in rear and E87 rear hubs in front. Aftermarket big brake kit.
CNC ported AMC head 43/37. Flows 173/134 at 10mm lift
89,6mm M54B30 crank
DP pistons 86mm/135mm Compression 9.0:1
Full RHD roller cam kit with (AGAP roller cam 296gr)
DBilas itb 45mm MaxxEcu sport
Headers with 2x2,5" stainless exhaust and dual race cats.

[MrBurgundy]

That is a nice curve, would be interested if you could post more details

2nd

[digger]

It is all about the total package head. This awd dyno result is from my m20 low comp na stroker build. It pulls harder than an original s54. With a bigger cam there is a lot more to gain.

That is a nice curve, would be interested if you could post more details

[skarlqvist]

It is all about the total package head. This awd dyno result is from my m20 low comp na stroker build. It pulls harder than an original s54. With a bigger cam there is a lot more to gain.

[zwill23]

I swapped my booster and master for an E93 unit as well after looking at prices for standard E30 boosters. Even with stock brakes, massive improvement in pedal feel and considering the price point and ease of modification this is a no brainer.

Car is looking lovely as always

[digger]

DId a booster and m/c swap along with 300mm/de BBK.


-Year and model of your E30: 89 325is RHD vehicle

-Intake manifold used in swap: m20 RHD ITB setup with own custom airbox. PLanning a new airbox and trumpets hence the mod as it creates more space

-Brake booster donor car: e93 320d

-Brake booster part number:34336779733

-Brake booster manufacturer and manufacturer PN or identifying marks: i thought TRW make them but cant be sure? it has single vacuum port, i oriented port closest to engine but it was on the otherside on the doner vehicle. some have 2 vacuumm ports just block one off.

-Parts needed:
e93 booster 34336779733
e90/92/93 m/c RHS version with ports on outside 25/22 34336785664
e93 clevis pin 34336753646
spring clip 07129904567
new o-ring for M/C 34311160617
new bung for M/C reservoir 2 x 34311160133
rubber hose for remote mount reservoir
remote reservoir 2002 bottle FTE brand p/n 9790000
connector for M/C to fit hoses for remote reservoir 2 x 34321102282
Booster vacuum port bung 34336765316
2 x M10x1 bubble tube nuts
2 x M12x1 bubble tube nuts
3/16" cunifer brake line
flare tool https://www.amazon.co.uk/Laser-TOOLS...01N39OIKA?th=1
line cutter

-Modifications needed:
booster unmodfied as clevis bolts right up with RHD vehicles as the clevis position is within a couple mm or the stock one but you adjust the brake light switch as required as pedal height changes a bit
to fit booster trim away the firewall insulation with a box cutter and/or scissors
trim the plastic firewall clips that retain the hard lines near the booster and lightly massage the lines by hand so boosters sits flush on firewall
i made two (2) new lines from ABS unit to the M/C using cunifer 3/16" tube and M10x1 tube nuts at one end (ABS) and M12x1 at the other end (M/C).
i dissassembled the rear pressure limiting device and removed the guts and reassmbled (optional step)

-Comments on pedal feel and stopping power: Brake are best they ever felt. i did this with 300mm.de 4x100 312x28 FR and 294x19 RR setup fully rebuilt with new pistons the e34 540i front calipers (60mm piston) and e36 m3 rear calipers (40mm piston)

after replacing almost entire brake system sans hardlines and ABS unit bleeding took a few goes and suggest using a Motive pressure bleeder with BMW adapter and following the steps in link a couple times or you wont get the system bled and pedal will be long and soft

https://bmwe30cabriolet-wdm.blogspot.com/2019/08/how-to-purge-your-abs.html

you could try a e92 m3 or e60 m5 M/C if you want a harder pedal but the 25/22 seems pretty close to perfect for my preferences.

[digger]

Latest looks, subtle changes