alainmengoli@hotmail.com
|
| posted on 23/3/04 at 08:17 AM |
|
|
throttle bodies
I've seen what seem very expensive fuel injection throttle bodies on engines before. The only thing I dont understand is how it works out the
fuel/air misture as their is no air meter thing?
Can they be bought for any engine i.e. alfa boxer 16v?
|
|
|
|
|
timf
|
| posted on 23/3/04 at 09:29 AM |
|
|
have a look at this site http://www.jenvey.co.uk will answer most of the questions
|
|
|
mranlet
|
| posted on 24/3/04 at 09:42 PM |
|
|
Mega Squirt!
Stand alone fuel management system would use a TPS and MAP or MAF sensors at the intake horns to properly map the ratios.
Unless you really really want open velocity stack induction, there are better alternatives for less money. You could get a 70mm throttle body from
www.jegs.com intended for a LS1, LT1, or Mustang 5.0 and build a plennium out of some steel or aluminum tubing (or even get one out of Carbon
Fiber).
While Individual Throttle Bodies (ITBs) will give you superior throttle response, open stack induction can be pretty risky for a drily driver since
there is no air filter, and will ultimately limit your top-end power, especially for turbo applications. A well tuned single throttle body and
efficient plennium can give you excellent throttle response as is and also be kinder to your motor.
-MR
[Edited on 24/3/04 by mranlet]
|
|
|
zetec
|
| posted on 25/3/04 at 12:47 AM |
|
|
The ECU has a throttle position sensor, it uses this reading to "look up" how much fuel it should allow into the engine. The "look
up table" will also have engine/air temp corrections and take into account engine speed. The ECU is just following a set programme rather than
working out how much fuel is required.
|
|
|
britishtrident
|
| posted on 25/3/04 at 10:17 AM |
|
|
Modern systems tend to rely mainly on the manifold vac and rpm transducers with throttle position and temperature as additional inputs, take a look
at megsquirt.
http://www.bgsoflex.com/megasquirt.html
Also see Dave Andrews Robin Hood site and the Jenvey site for more info.
|
|
|
NS Dev
|
| posted on 27/3/04 at 10:12 AM |
|
|
most afetrmarket competition systems don't do this though! The extra inputs slow response. My MBE system, DTA, Emerald etc all use throttle
position and crank position only and just lookup on the eprom from these(plus correction maps for water temp and air temp) This gives a lightning
throttle response, and I have used my MBE system on the road in an Opel Manta for a couple of years with no problems. I think the extra inputs are
overkill unless you have to meet the very latest emmission requirements, particularly the air mass meter which is very slow to react (relative to
engine!)
|
|
|
