M52B28 Intake Manifold Change

[Slide]

Oh and lets not forget that the standard GM gearbox is already know to be weak and once you start forcing more power through it, it's only going to shorten the life span even more. I've done 2 rebuilds already.

 

[8080pbmw]

!! Thanks Slide ,


There's no easy and "cheap" BHP after all.

Of everything about the car, I love the mid range delivery of the torque the most. City driving is a dream. But I am pleasently surprised that 325 would benefit more from the 320 manifold in terms of daily driveability in the city.

So far my car's engine is stock standard except for the K&N drop in filter.

The reason I wanted to seriously look into the M50B25 intake manifold is due to the curiousity after my dyno of the car. I have been wondering about this mod ever since I got myself the car.

Come to think of it, all the 328i figured in those mags are manual. My automatic transmission also have yet to be rebuild with 150K km already. Doing the mod might just be the bullet to the head for the tranny.

I'll take your advice and only make a firm decision to mod or not if I get the opportunity to drive a 328i with the same mod.

IMHO, saving up ( if able to ) for a ///M is the best way to get a machine that will satisfy most petrol head. Else will have to get a Japanese all-wheel drive turbo charged Imprezza.

Wait and see if the venom can be clear of my system.

Cheers.

 

[Slide]

No worries, glad to pass on advice. What rwbhp did your car make on the dyno?
If you want to look into mods, you might just want to see if your car is still on it's original cat. If it's rattling then a proper de cat will get you like 5 bhp. Other mods, like super sparkplugs, voltage stabalizers, pulleys etc, will only get you 1bhp at most and is not worth the money.

 

[LCP]

Whoa, how can I miss this thread...

8080, in my opinion, stock 325i sucks at low rev, city driveability at low revs is just plain sedated (just like me today, out sick on MC)... Anyway, as the revs get higher and higher, the pull gets stronger and stronger, and it will continue pulling even past 6000rpm, after that I dare not try already, balls not big enough. I guess the way they designed the manifold is very important, it must not only be able to flow large amount of air without restriction (M50B25 manifold), but at light throttle (read: small amount of air), it should be able to give the responsiveness for better driveability (M50B20/M52B28 manifold)... having said that, there are some car manufacturers with manifold design can actually varies the path length of the air intake depending on the amount of air flowing through, not too different from the M52B28 muffler concept...

You should go for the M50B25 intake manifold, but if possible, get a feel first from a car with such mods... The hit at low revs will be there but since the engine is bigger (no replacement for displacement, as they say), it may be liveable. Also if you wanna do US M3 cams, the hit at low revs will even be more as the cam profile is designed for higher revving engine...

 

[E3six]

Slide you sound regret of your effort spent on your mod......!!!!

Sometime we learn thing thru a hard way, may be you exspect more of what your mod result shown. May be i guess if you have manual tranny, all will be a different ball game to play. It will just keep you going ...n ...going....n...going.....

BTW, never too late to consider manual tranny when your GM going to junk yard.

Cheers....

 

[LCP]

Each to his own... everyone's got their own way of modding... for Slide's case, I think he would learnt quite a bit more, not only on technical details, which one won't get by dumping in a M3 engine.

Yeah, go manual... a decision that won't be regretted...

 

[fabianyee]

having said that, there are some car manufacturers with manifold design can actually varies the path length of the air intake depending on the amount of air flowing through, not too different from the M52B28 muffler concept...

The E36 318is (M42, M43 and M44) has such variable effective lenght intake manifold...
On these 3 engines, the intake design has 2 parts after the throttlebody: 2 primary intake pipes and 4 secondary intake pipes going into the air intake ports.
Below 5,000rpm, the butterfly at the junction would be closed and each of the primary pipes would channel air into 2 secondary pipes. Hence the cross section of the air pipe is smaller, hence more momentum at low to mid range RPM and giving better torque.
After 5,000rpm, the butterfly at the junction would be open and free for all the 4 secondary pipes. The total cross section of the primary pipes is now increased, allowing more air to flow at the high RPM range so that the engine doesn't run out of breath.
So it doesn't vary the length physically but it increased the cross section of the pipes. However, the 'variable' cross section was equated to 'variable effective length'...
It's the same principle for most other variable effective length air intake ie Citroen ZX 16V..

The explanation above is based on my understanding on how it works. U can google for further information.

 

[E3six]

fu yo biyee !! so technical lah you.....

 

[8080pbmw]

No worries, glad to pass on advice. What rwbhp did your car make on the dyno?
If you want to look into mods, you might just want to see if your car is still on it's original cat. If it's rattling then a proper de cat will get you like 5 bhp. Other mods, like super sparkplugs, voltage stabalizers, pulleys etc, will only get you 1bhp at most and is not worth the money.

Just dyno last week. Getting approx. 163rwbhp and 242 Nm.
Standard Cat is still in the car. Basically no mod on the engine.

 

[8080pbmw]

another chart for the torque.

Slide,what sort of rwbhp and torque from your mod?

 

[8080pbmw]

my hood. file size too big.

 

[LCP]

my hood. file size too big.

Hood? Hmmm, that sure ain't don't look like no hood...

 

[LCP]

Yes, fabian, effective length is the correct term... Not on race cars though, they only need all out air flow at high revs... (although M50B25 ain't no race engine)...

 

[Slide]

The muffler flap on the 328 is there only for noise reasons, it does not do anything else according to a BMW bulletin i read sometime back.

Yeah, a manual conversion is the way to go, best mod to do to a 328 if you ask me, but i still need my auto as i can't take driving a manual everyday.

I stopped going to the dyno after i blew my gearbox out on a run, but i was putting out 170rwbhp and that was with my stock air filter and a dead cat convertor.

 

[8080pbmw]

Hood? Hmmm, that sure ain't don't look like no hood...

"My hood"is a term I picked up from my friend who is living in Philadelphia.
It meant my fault. Another term the Brothers or the Hispanics there used for "My Bad".

 

[8080pbmw]

The muffler flap on the 328 is there only for noise reasons, it does not do anything else according to a BMW bulletin i read sometime back.

Yeah, a manual conversion is the way to go, best mod to do to a 328 if you ask me, but i still need my manual as i can't take driving an auto everyday.

I stopped going to the dyno after i blew my gearbox out on a run, but i was putting out 170rwbhp and that was with my stock air filter and a dead cat convertor.

170rwbhp before all the mod? wondered if it's 200++rwbhp now.

 

[GT35R_BMW]

A comparison between a m52 and a m50 mani.

 

[Daniel E30]

hi guys,
Im new here and just got my e30. Stumble upon this tread whilst looking for some info about M52B28. I just got an E30 with a M52B28 engine and original manual gearbox, mated with the E30 LSD. As ive not really tested this car to the max, i can just contribute some comments, that a manual conversion is definately worth it. It pretty quick, esp the pick up, at least from my impression. I was a honda H22A auto owner previously.
I thank the previous owner of my car for making this conversion, but i really know nuts about E30 and M52B28. Im free for TT if any of you guys want to meet up...

regards :

Daniel from Damansara Damai, Sungai Buloh.

 

[V-Man]

hi guys,
Im new here and just got my e30. Stumble upon this tread whilst looking for some info about M52B28. I just got an E30 with a M52B28 engine and original manual gearbox, mated with the E30 LSD. As ive not really tested this car to the max, i can just contribute some comments, that a manual conversion is definately worth it. It pretty quick, esp the pick up, at least from my impression. I was a honda H22A auto owner previously.
I thank the previous owner of my car for making this conversion, but i really know nuts about E30 and M52B28. Im free for TT if any of you guys want to meet up...

regards :

Daniel from Damansara Damai, Sungai Buloh.

Congrats on your purchase bro..Welcome to the bimmer world. Me too ex-honda EG6 owner..hehe...You bought the white E30 ah ?

 

[Daniel E30]

Hi...yeah. The white e30. Got it frm leong...frm ss2.