E36 328i throttle body conversion....
Discussion
daveco said:
Can this be done an E46 325? I'm very interested to see what gains can be had as I plan to dyno the car again shortly.
Seeing as you already have a 325
probably not... You may find an improvement with a throttle body, but I'd probably hazard not.
Save your beans for a bigger engined car if you want more power, as the 325 came out of the factory as it should have, unlike the 328, which was restricted by the factory; hence you probably wont see any improvement.
Neil_Bolton said:
daveco said:
Can this be done an E46 325? I'm very interested to see what gains can be had as I plan to dyno the car again shortly.
Seeing as you already have a 325
probably not... You may find an improvement with a throttle body, but I'd probably hazard not.
Save your beans for a bigger engined car if you want more power, as the 325 came out of the factory as it should have, unlike the 328, which was restricted by the factory; hence you probably wont see any improvement.
Shirley all BMW's are fitted with the restrictive airbox, and by removing it you are helping increase air intake, thus power?
daveco said:
Neil_Bolton said:
daveco said:
Can this be done an E46 325? I'm very interested to see what gains can be had as I plan to dyno the car again shortly.
Seeing as you already have a 325
probably not... You may find an improvement with a throttle body, but I'd probably hazard not.
Save your beans for a bigger engined car if you want more power, as the 325 came out of the factory as it should have, unlike the 328, which was restricted by the factory; hence you probably wont see any improvement.
Shirley all BMW's are fitted with the restrictive airbox, and by removing it you are helping increase air intake, thus power?
Perhaps, but then it wouldn't be a throttle body conversion or inlet manifold coversion would it?
Additionally its all very well increasing airflow, but you need a remap to make anything of it as the fuelling needs to be adjusted properly. I'd hazard that you'll see more performance from using VPower than just a slight increase in airflow - I have an air filter (as do many) and all it really does it increase the induction noise...
Edited by Neil_Bolton on Monday 23 April 13:01
Edited by Neil_Bolton on Monday 23 April 13:03
daveco said:
Neil_Bolton said:
daveco said:
Can this be done an E46 325? I'm very interested to see what gains can be had as I plan to dyno the car again shortly.
Seeing as you already have a 325
probably not... You may find an improvement with a throttle body, but I'd probably hazard not.
Save your beans for a bigger engined car if you want more power, as the 325 came out of the factory as it should have, unlike the 328, which was restricted by the factory; hence you probably wont see any improvement.
Shirley all BMW's are fitted with the restrictive airbox, and by removing it you are helping increase air intake, thus power?
No, because the airbox becomes more restrictive for for higher engine outputs. In other words an airbox that is sized correctly for, say, a VW Polo 1.4 and is not restrictive would almost certainly be restrictive for a 2.8 litre BMW for instance.
[extreme example]
Or put another way, the bigger engine sucks harder. If you suck softly through a certainly diameter straw- the straw is much more of a restriction or a bottle neck when you suck harder.
nicedude1976 said:
Would NOT say all BMWs have restrictive air boxes. Only had 320(24v) and it was one of most free-reving engines I experienced.
As far as re-mapping for 328 - do you really need it, as increased air flow will certainly be recorder by air flow meter etc ?
The air flow will have a maximum upper "clamp value" or limit and if you flow out of range of this your fueling could be out. I have no idea if this would be the case for the 328i.As far as re-mapping for 328 - do you really need it, as increased air flow will certainly be recorder by air flow meter etc ?
The MAF sensor wont control ignition and with more air flow you need less ignition....and this wont be reflected in the original map.
daveco said:
Neil_Bolton said:
daveco said:
Can this be done an E46 325? I'm very interested to see what gains can be had as I plan to dyno the car again shortly.
Seeing as you already have a 325 probably not...You may find an improvement with a throttle body, but I'd probably hazard not.
Save your beans for a bigger engined car if you want more power, as the 325 came out of the factory as it should have, unlike the 328, which was restricted by the factory; hence you probably wont see any improvement.
The Ulf said:
right, can anybody now tell me if i can simply fit the S50 throttle body together with my M50 inlet manifold onto my M52 engine? is there much "tweaking" involved or do the parts fit just like that?
You're better off going onto e36coupe.com and PM'ing alpina527. He's done loads of the kits and will get you all the bits you need as they need to be modded slightly. Have a go yourself if you feel confident though by all means. 
se6b said:
Its been nearly 24hrs now since I removed the restrictor and I have come to some conclusions;
1) The difference in noise when you plant your right foot is unbelievable. The only way I can describe it is that it now sounds like a touring car above 3500rpm. Theres a proper hard edged yet musical induction boom. It sounds like the engine has grown in capacity.
2) There is no difference whatsover in noise in normal relaxed driving.
3) It does feel like there is a bit more midrange and certainly top-end power. This could simply be down to the fact that it 'sounds more exciting'. Hard to be sure without figures.
4) That flat-spot at 2500rpm is still there
5) There are no problems with running at all. No stuttering at low revs. It drives exactly the same. The difference only becomes apparent above 3500rpm, and its a positive difference.
6) If you have a 328i you MUST throw your restrictor from the nearest cliff.
THANKS GUYS!!!!
Im sold, recently bought a 328i and although i love the sound when i fire her up, she does seem a bit muted when i floor it so this will help big time, will give it a go this weekend. Gracias1) The difference in noise when you plant your right foot is unbelievable. The only way I can describe it is that it now sounds like a touring car above 3500rpm. Theres a proper hard edged yet musical induction boom. It sounds like the engine has grown in capacity.
2) There is no difference whatsover in noise in normal relaxed driving.
3) It does feel like there is a bit more midrange and certainly top-end power. This could simply be down to the fact that it 'sounds more exciting'. Hard to be sure without figures.
4) That flat-spot at 2500rpm is still there
5) There are no problems with running at all. No stuttering at low revs. It drives exactly the same. The difference only becomes apparent above 3500rpm, and its a positive difference.
6) If you have a 328i you MUST throw your restrictor from the nearest cliff.
THANKS GUYS!!!!
e36coupe.com seems broken, even tho i still have the email here with my login data it keeps on telling me that my username/password are wrong, which is weird. i tried emailing alpina527 last weeks wednesday on his old aol-address. no response yet. is he still alive and all? he may have got a new email adress tho. not being able to log into e36coupe.com and him not replying to my emails is quite inconvenient somehow...
Shropshiremike said:
The Ulf said:
right, can anybody now tell me if i can simply fit the S50 throttle body together with my M50 inlet manifold onto my M52 engine? is there much "tweaking" involved or do the parts fit just like that?
You're better off going onto e36coupe.com and PM'ing alpina527. He's done loads of the kits and will get you all the bits you need as they need to be modded slightly. Have a go yourself if you feel confident though by all means. different question: has anyone ever tried to retrofit an OEM (yes, i don't want poxy aftermarket shite) cruise control to above mentioned m52 engine? what cost would i be looking at and how much work would it involve? in my youthful naivity i would reckon that the main loom is pretty much standard and therefore prepared to be extended for additional functions fairly easily.
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