RomRaider

Has anyone used a Bosch 0280160575 fuel-pressure regulator (4 bar, instead of 3,5 bar) on an M52 before?
Is this a viable way to get more flow from the Pinktops i have? Any Downsides?

Diameter of the brass part didnt fit...luckily the groove for the small O-Ring is similar enough to just turn the diameter down and reuse the old O-Ring.


With tune unchanged it gained around 1 point AFR towards rich (13,3 ish to low 12s).
Currently retuning...

Quick Update on the build:
Its on E85 now for nearly 10.000km, fuxk paying 1,8€/L
Except for it emptying the tank faster i dont even notice anything related to the E85, can recommend!
The dieselcrank is hanging in there for now 40.000km. Rev limit since the cams is 7300.
Went to the track a couple times with it also.
https://www.youtube.com/embed/xPZPgOgHz4E
...still the daily driver

nice passing the porsche. what is the power output now?

I think you meant the renault alpine at the end? Was hard to get clean laps...i think i can improve the laptime a bit more do you go to the track in yours?

I had a look a your acceleration video yesterday with the 100-160 and
i am much slower than you. On the other hand i am at ca 1500+kg and have the high class 2 wing, so its expected that mine is not the fastest accelerating...
It was never on a dyno so i have no idea about power.

ah ok. it looked like a porsche boxster. hard to tell new cars apart for me.. that is quite a hefty e36 weightwise. last time i had mine on the scale with only quarter tank was 1320kg. with me it is like 1440 which is also not that light. sometimes i wish it didnt come with ac to save weight.

no. never raced mine on a track other than tearing up the backroads roadtuning where i live. too bad i cant get e85 here, so im stuck with 98 or 102.

yeah. putting the m50 mani back on saved over 2 seconds in 100 to 160 time...go figure...

15 years ago i would have said the same, whrn i started ripping out carpet and doorpanels etc. from my very first e36. Nowadays i dont want to miss the heated seats and the automatic ac in my e36 in reality the couple ok kilos wont make a difference. Its either full racecar with zero stuff in it or leave it alone as its ruined for streetuse when only done half

Have you experimented with octane 95 vs 98 vs 102? Have you found that the higher advance that the better fuel allows gets you closer to optimal torque output? Have you tuned yours on a dyno?
The e85 for me is a pure cost saving measure i run nearly the same spark map as with 98.

Regards the manifolds i looked at the s50b30us vs the s52b32 in the past and my takeaway was that if the 3.2l makes 240hp with the m52 manifold and the 3.0l makes the same with the m50 manifold with very similar cam specs, then the impact on engines making below or around 200hp should be even less?
But your tests clearly show a bigger difference than i would have guessed!

I also try to keep everything for street usability. not into the pure track stuff.. i just wanted a nice daily driver in summer with a little bit more pep...hence the cams and mods...

about the fuel grades: i cant really tell a difference between 102 and 98 octane. neither in the logs nor butt dyno. i did try 95 with my tuned ign map and the car wasnt happy. it felt really bad and recorded knock also.

so, when i just cruise around i tank 98. and when i plan to rip on it, i put 102 just for safety...

unfortunately, when i went the second time on dyno with the cams i could only do three runs. And i did raise the ign about 3 degrees between runs. first run almost stock ign. second run + 3 degree and third run another +3 degree. i dont remember the exact number but the difference between the first and third was like 8hp or something. however, it did record some knock on the third run. however, could be due to the high iats that day . it was betwen 35 and 40 degrees. so, not really good for na power..

after the third run time was up and couldnt test further. i think to really tune it and try all sorts of different setups, you will likely need almost half a day on a dyno

about the manis i had the same thought also before that if this m52 is good for s52b32us, then it should be more than enough for little b25.. but the numbers just tell a different story. I even tried porting the m52 mani and while it did feel great at mid rpm, it just misses that punch above 5500rpm compared to the m50 even with cams...

...yeah with these prices running 102 gets costly. Before E85 i would use the 102 for trackdays as extra safety. And run 98 the rest of the time. But i am not shure if even 98 is worth it right now. If i hadnt E85 i would propably go for E10 =D


yeah, a good A/B-test is worth more than a thousand forum pages
...for my setup its pretty much set that i stay with the M52 manifold because of the smallport-head. I dont think the M50B20 manifold can make a huge difference because its runners are somewhere between M50B25 and M52 in size. But now i regret that i sold the one M50B20 mani i had without testing it properly =D

Have you ever looked into the M52TU/M54 manifolds? In theory the different resonance lengths seem nice. I think pazi was talking in the past about using one of those for his high-compression NA-build!

yes, i looked into it. but its too much jerry riggin for my liking.

but here is someone who done it

https://e30-talk.com/topic/205680-m50m5 ... -eigenbau/

thanks for the link, interesting read!

How's your stroker now? I recommend you to go for M50B20 manifold. With it, my M52B20 breathes well better over 5k rpm. And my friend has similliar engine dynoed at 171HP. Other guy from polish E36 forum also dynoed 323i with it at 195HP. It seems that M50B25 manifold is useless at it's price.

Is there a log from that dynopull?
Its a stock m52b25 with just m50b20 manifold?

No log. Afaik, bone stock with just the manifold and a tune.