Hi all,
I'm currently running twin 40mm Kadrons and a turbo blow through set up on my 1915 which has its shortcomings when at full noise due to (I'm pretty
sure) the carbs not being able to keep up. I.e. I think getting the right mixtures acros the rev/boost range is a bit beyond the Kaddies.
Does anyone have any thoughts/experience with fuel injection? I've found a CB Performance kit online but can't seem to see how much it is... Does
anyone know of alternatives?
Should I just 86 the idea of EFI and go to Webers?
All feedback greatly appreciated....
Thanks, Marc.
They are $3175 for that kit from CB. Quite good kit especially for newbies.
I plan to get one one day and do away with the ecu and throw in a megasquirt and water to air intercooler.
Here is the link http://www.cbperformance.com/catalog.asp?ProductID=1665 to the price on their website. US$1,795 seems OK for a full
system that is tested to work with an air cooled engine.
Yogie
lol my bad i was thinking their EFI turbo kits not normal EFI
EFI vs carbs for a turbo engine?
EFI will win everytime when properly tuned. You can adjust your mixture to be as near perfect as poss in every area of the rev range. The tuning is
the key. There are a lot of good ECUs to choose from these days. You just need someone who can tune it properly. So the question is my mind wouldn't
be, "is EFI worth it?", but rather, "who would you get to tune an aircooled turbo engine with EFI?". Brendon at production automotive has built
just such a setup, be worth talking to him. He's on the forum too.
Re the setup, I would look into some late factory twin port manifold ends with the injector bosses and a central custom made manifold. This would be
very easy to make too. This is the setup lots of the promod cars are using in the states. Then some sort of common throttle body. I just can't see
the need for twin or quad throttles on most turbo setups and if you want to confirm this look under the bonnet of a GTR and you'll see what I mean.
The other upside with this would be no need for balancing the TBs. It's also cheaper, which is always nice.
There are lots of guys who have done this sort of setup on the forced induction forum of Shoptalkforums in the US. Ask on there and see what they say,
but ultimately you will need a local to tune it. Ben Durie is up your way, have you talked to him?
If your interested in single throttle body setups a good option is the mexican EFI manifold with any aftermarket computer of your choice. Have a look on thesamba classifieds, theres a guy on there called mario putting together kits with Megasquirt computers for quite reasonable money which include pretty much everything you need. I'm pretty sure Rod Penrose usually has second hand or new CB kits available as well
yeah, that's what I was talking about.
try this thread out...
http://www.shoptalkforums.com/viewtopic.php?f=3&t=125546
and there are plenty more on this section of the forum too.
Quote: |
how big a pleum? Is there a magic volume?
Thanks everyone, great info for me to digest. Thanks Pete, no I haven't talked to Ben, but I will include talking to him on my
research/buying/installment journey. I'm pretty sure I'm going to go the EFI way, but at the prices they are I might be playing at Stockton a little
while longer on the Kadrons while I save the bikkies!
Will also chat to Rod this week and see what the go is. That Shoptalkforums is a great site too!
Cheers, Marc.
in regards to sizing of plenums and intakes, Bernoulli's equation is ur answer , google it up
depends if u want high top end or good bottom end torque. Smaller diameter/longer inlet manifolds from plenum results in higher velocity air and
natural supercharging effects for ur low down power . But can get
restrictive at top end... but depends what range u wanna hang in...
Unless u go tricky and have the best of both worlds like Toyota TVIS or ACIS :P (naturally based on changing pipe cross sectional area (for tvis) or
length of plenum (acis) to achieve it. Its not hard. just involves a vac operated butterfly setup activated when a rev range is hit (via frequency
switch, after market ones are available)
To minimise flow losses u could use the info from bernoulli's to obtain a 'reynolds' number to make sure its slow enough velocity for laminar flow
(at least till it gets to the combustion chamber)
Quote: |
With regards to plenum sizing I'm stuck with the factory german plenum volume, but the volume from the throttle plate to the airfilter has an effect
as well. I'm planning on just popping a filter on top of the throttle body for simplicity initially but then Id like to make up some simple variable
volume pvc thingy to try on the dyno once its all running well. If I find a volume that produces good results then Ill fab up something that fits in
the engine bay to produce the same effect.
There was a fellow in the states, (bob hemphill I think) who managed to get the same manifold setup as mine into the 10's in a fairly heavy car, but
just because its been done doesnt mean its the ideal way to chase that sort of performance.
Quote: |