Author Topic: Possible ITB MAP solution?  (Read 4724 times)

Offline Sprockets

  • Jr. Member
  • **
  • Posts: 79
  • BHP: 5
Possible ITB MAP solution?
« on: May 04, 2008, 01:50:31 pm »
Hi all,

Was searching the MS forums earlier seeing what was going on and stumbled upon this.

http://www.msefi.com/viewtopic.php?f=92&t=29502

I've built similar for carb synching before, but this was an interesting application, and near the end a simpler solution involving a simple diode setup was discussed and used to good effect on a bike engine.

Just thought i would post the link as it may solve a few peoples problem if they don't want to run Alpha N.

Also discussion on using it eventually for cam sync.

-Gavin

Offline gunni

  • Hero Member
  • *****
  • Posts: 1492
  • BHP: 37
Re: Possible ITB MAP solution?
« Reply #1 on: May 04, 2008, 05:06:02 pm »
I think the ideal solution is the same as on the E36 M3,
it´s got a rail much like a fuel rail in size, that is connected to each ITB, and the fpr and brake booster is connected to that.

in effect a chamber that houses all the itb signals.

Offline Sprocket

  • Hero Member
  • *****
  • Posts: 867
  • BHP: 29
Re: Possible ITB MAP solution?
« Reply #2 on: May 08, 2008, 12:07:09 am »
Not exactly a cheap option though with four MAP sesors :o

I have been looking at 'T' off all four ITBs in three stages, to give a sort of dampened effect. Basicaly T off from the center between two ITbs, then T off from the center of that and T off again, that way there is more than one one parh for the pressssure to follow, and also adds volume.

Thing is, i have now ditched the ITBs again ::) in favour of a plenum annd single TB ;D

Offline GintsK

  • Hero Member
  • *****
  • Posts: 1257
  • BHP: 50
Re: Possible ITB MAP solution?
« Reply #3 on: May 08, 2008, 01:23:31 pm »
If it is turbo, then...

I have experience with MAP and ITBs on VW 16V engine. Four vacuum hoses was attached to ~50cc plenum and MAP hose goes from this.

Result was weird VE map with wide low, flat area. And then at huge slope at two highest MAP bins. So at partial throttle AFR was under poor control. We migrate to Alpha-N and from that time I never try run ITBs on Speed-density.

 BTW cams was relatively narrow.