M20 B3x Naturally Aspirated Stroker build past, present and future

[zoran]

Sorry for that,untill I finis it I will not post any moore.
Regards all.

[LJ851]

Hi Jon,thank you for a help,no chip just oem 173 ecu as I stated that is just test,I do work in USA I dont live,98ron is 91oct in USA,let see can it get any close to 240whp with my setup.I need to wait for vems.

Hey zoran, your build sounds pretty interesting. You should start your own thread here in the project forum instead of posting in digger's build thread.

[zoran]

Hi Jon,thank you for a help,no chip just oem 173 ecu as I stated that is just test,I do work in USA I dont live,98ron is 91oct in USA,let see can it get any close to 240whp with my setup.I need to wait for vems.

[ForcedFirebird]

yes it is on motronic as 2 days ago i ordered VEMS so i have to wait until gets in my hands and then we will se what is going on.

Unless you made a chip for Motronic, that's probably why you are getting knock. Your profile shows you are in the USA, but we don't use RON rating, we use octane. I have a feeling using e100 won't help you much, either (until you get VEMS installed), as you will need to add a lot more fuel vs conventional gasoline (again, you would need a chip for that).



How much is your cranking compression? Anything much over 235psi and gasoline will self ignite (using 93 octane, not sure how that translates to RON). Before changing pistons, might want to go with more cam duration (Schrick makes a 304°) to bring your trapped mass down int he lower RPM.


Here is the stock timing table:





As you can see, the reason your knock is probably going away is BMW pulled almost 10° timing at mean torque (~3600-5000rpm) in the higher load areas. If you lowered the timing advance before 3600, you would have less issues, might even be able to get away with pump gas.

[zoran]

yes it is on motronic as 2 days ago i ordered VEMS so i have to wait until gets in my hands and then we will se what is going on.

[digger]

Yeah I wouldn't contemplate changing pistons at this stage if you have the option for ethanol.
It sounds like you are still running motronic and not tuned so you need to finish install the standalone and get it tuned.

[zoran]

do you know who can make it maybe Steve from Top End performance,before i change them I will try batlle with these because if knock is gone after 3600rpm on 98ron than e100 with 114ron may help a lot,what alu spec to choose because it is event engine once a month for show that is.

[digger]

What fuel ? E100 is ethanol? You have that as pump fuel near you ?

That's too much for pump fuel petrol/gasoline i.e.98ron for sure

You can make OE style with that CR but it won't be exactly the same and needs to be modified but uses the similar philosophy. need to be careful though big dome starts going backwards if you block flame travel

Proper ecu and tune are required before you throw in the towel.

[zoran]

thank you for post,Iam using ross pistons,dome top is -9cc,stock ignition,no tuning at all as i just test it and realise that is going to be very hard on pump fuel to achieve anything on that cr,yesterday I ordered vems so we will se how it works.Top of piston is not as oem at all but it is not posible at all to achive that level of cr with oem shape,i wish to be as oem but at this moment it is impossible.

[digger]

They are ZRP rods though these are not on their website which last time I checked still shows the older version with the beefier cap.

No experience with ethanol but I would have though pure ethanol would be fine at 13:1. What pistons are you using and what ignition timing? Has it been properly tuned ?

[zoran]

i beam rods

hi,do you mind to share rod manufacturer and on camshaft 288/288 shrick do you have expirience regarding e100-etanol what cr can I go because at this moment is cr13-1 and I am having nock from 2600-3600rpm on 100ron fuel,after 3600rpm it is gone and car puls like it is on 1bar of boost.I hope you make that 3.3 just to see that is possible,:devil::devil::devil::devil::devil:
regards.

[digger]

Baby steps….

Painted the manifold and finalised the nipples for
- Idle control valve elbows strategtically angled to suit vacuum rail
- Single Brake Booster nipple
- Seperate Vacuum nipples for synchronisation

the metal plate is an alignment tool so that when i bolt the manifolds to the head the relationship between the the 3 castings is maintained.

i have a seperate plate for mounting the throttles so the shaft remains concentric to ensure that at WOT they each open the same amount







Remade the vacuum rail





A bit overkill but a nice beefy but compact set of aftermarket I-Beam rods. Stock length 135mm but bushed to 20mm. The usual details 3/8" ARP 2000 bolts, forged and heat treated 4340 steel, shot peened…..





Everything in CAD, mostly cause why not....oh and also need to design a crank scraper and windage tray setup. Still work in progress got to get all the holes in the right spot on the block. Some stuff is just representative

[digger]

Mine feels much like a stock clutch to be honest it's not abrupt. There a slightly higher rated organic you can get rather than stock m5 but I don't know details

[SLEEPYDUB]

Hey Digger, It probably feels like im stalking you by now but I promise im not. Just have a question regarding your clutch and pressure plate setup that was mentioned on your first post, the HD 240mm m5 setup. I am using the same type setup on my m20. Its the RHD flywheel with the Sachs 765 pressure plate, and the organic full faced m5 clutch disc. I've been using this setup for about a year now and its been ok, but the issue im having is the clutch engagement feels abrupt and short. Meaning it only takes a little bit of travel off the floor and once its starts to engage its very quick. I used a stock throw out bearing, not sure if that will hinder its performance, and also used my stock slave cylinder. Can you share any insight to how yours feels?

I have been drifting on this clutch and after 3 events i think the disc needs replaced, because its starting to slip in 3rd on high boost. Will likely upgrade to a 6puck, or do you have another recommendation that uses the 240mm?

[digger]

As for price they were cheaper than what MM now charge for a set of theirs