possible delay in acceleration?? ideas please

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taylorstattoo
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Sat May 11, 2013 9:02 pm

hi all.
just wondering if this sounds familiar to any one, and stumped on what might be causing it.
m52b28 fitted with m50 inlet e30 flywheel ect, as a quick fix to get the car drivable i made the exhaust manifold 6 into one and i am using the single pipe i had on it befor but, this was only temp as have been told restricting the engine to much would cause it to heat up more, So when test driving it i found that it would sort of pause befor t took off at the end of the rev range,, i was thinking this was due to the restrictive pipe, but after getting in back from a garage that did my bushes im not to sure as they seem to think that if it was restricted it would be quicker low down the revs and slower high up, is there some thing else this could be.
The car ticks over fine and drives fine but like i said low down in the revs it seems like its holding back then all of a sudden it takes off, cheers steve..
taylorstattoo
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Sat May 11, 2013 9:30 pm

anybody??
:idea:
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rich318i
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Sun May 12, 2013 12:50 am

e36 spec keep it e36 spec. put the M52 intake back on be sweet. or get it remapped.
taylorstattoo
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Sun May 12, 2013 10:58 am

really?? every body seems to be doing the m50 inlet conversion and have not herd anything about this befor ,,
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ajay
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Sun May 12, 2013 11:46 am

Have you had your fault codes read to see if anything is amiss?
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randomspeedfreak
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Sun May 12, 2013 11:57 am

can you get a video up mate? might give people a better idea of what is going on
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blue30
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Sun May 12, 2013 12:17 pm

Don't think it sounds exhaust related, I drove a car with a blocked zaust once and it was OK low down with no mid/top end.
taylorstattoo
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Sun May 12, 2013 2:44 pm

have not had the time to get codes read as garage that does that is not close and my only time off is sundays, if it was the restriction would that show up on the code reading thing,
jmc330i
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Sun May 12, 2013 4:23 pm

taylorstattoo wrote: So when test driving it i found that it would sort of pause befor t took off at the end of the rev range.
Can you explain this a little better? At full/part throttle, only at high revs, what do you mean by a pause?

It doubt it will be the M50 manifold etc, plenty of people run these without issues. I doubt it would be the exhaust pipe either - a restrictive exhaust won't cause a stutter/pause and then let it rev as normal.

Possibly not related, but how have you fitted the 2 lambda sensors into 1 pipe?
James
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'93 318i touring 16v
taylorstattoo
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Sun May 12, 2013 5:43 pm

both lambda`s are still in the manifold just further down a bit, it ticks over fine and seems to drive fine but after pulling off normally if you then floor it it will climb quite quick but not silly then just flatten off for a second befor taking off real quick like a vtec or s/charger has kicked in, not really a prob as the car goes like stink but i was under the impression from everyone that because iv used the 1.8 gearbox and swapped the fly wheel, that it would spin up alot faster, mine seems to be doing the opposite and lagging low down then taking off high up, maybe this is normal then,, ill try and get a vid up to mo to explain it better
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Brianmoooore
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Sun May 12, 2013 5:47 pm

What injectors did you use with the M50 manifold?
taylorstattoo
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Sun May 12, 2013 5:49 pm

m52 ones.. 8O
penton08
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Sun May 12, 2013 6:41 pm

I would get it plugged in first to rule a few things out, (o2 sensors plugged in the wrong way round, ect ect) but fitting a m50 manifold does create the feeling of a loss of low down grunt. It is not as noticeable in the lighter e30 but in a e36 it can feel flat until 4k. A remap will do a lot to help this :)
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ajay
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Sun May 12, 2013 6:49 pm

Also what type of kit did you use for the m50 inlet conversion? Have you checked for air leaks etc.
age
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Sun May 12, 2013 7:37 pm

you are sure your m50 manifold is from a 2.5 yea?
M40 rightness if you can get to 6000rpm noone can hear your tappets
jmc330i
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Sun May 12, 2013 9:02 pm

age wrote:you are sure your m50 manifold is from a 2.5 yea?
The 328i uses the same manifold as the 320i M50, 320i M52 and 323i.
James
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taylorstattoo
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Sun May 12, 2013 9:53 pm

yeah its the right one, port holes are loads bigger,
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Brianmoooore
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Sun May 12, 2013 10:16 pm

jmc330i wrote:
age wrote:you are sure your m50 manifold is from a 2.5 yea?
The 328i uses the same manifold as the 320i M50, 320i M52 and 323i.
The inlet manifold on a M50B20 is very similar to a M50B25 at first sight, and not at all like the restrictive manifolds on some of the M52s. The M50B20 manifold does not give the gains that the 2.5 version does though.
jmc330i
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Mon May 13, 2013 9:47 am

Brianmoooore wrote:
jmc330i wrote:
age wrote:you are sure your m50 manifold is from a 2.5 yea?
The 328i uses the same manifold as the 320i M50, 320i M52 and 323i.
The inlet manifold on a M50B20 is very similar to a M50B25 at first sight, and not at all like the restrictive manifolds on some of the M52s. The M50B20 manifold does not give the gains that the 2.5 version does though.
Ive seen M50B20 and M52 manifolds for 323i (2.5l engine) and 328i with the same part no. 11 61 1 707 027 ??
James
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'93 318i touring 16v
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