hacker-pschorr

+1

One of these days I'm going to drive down to Mike's shop with a briefcase full of cash and I'm not going to leave until he agrees to make me a set.


/or until he calls Greg Nettles to have me removed.....

911tracker85

thanks. yea I knew I would need something. have seen threads where people installed megasquirt.

am I crazy to even consider trying this?

I have done a lot of wrenching on my 928 and 911, but no experience digging into FI systems. I am a computer network engineer, so I suspect I can learn.

maybe I should just save my nickels until I can afford an SC kit. but the tinkering is a big part of the fun.

hacker-pschorr

You will be limited on how much power you can make with the stock L-Jet system with your 84, which is why I ditched it for LH 2.2 from a EuroS on my 81.

That was fun, now I'm dropping that for a 3rd party stand alone........ it never ends.

123quattro

Not to derail this thread too far...

I borrowed davek9's spare 5L short block, I have spare 2v heads, and I also have 2 sets of GSXR ITBs. I'm going to try and make it work this winter. My plan is to have the car running for Power Tour next summer. I'd be happy with 310whp.

Lizard928

Bob,

Not to high jack further, but wanted to answer your question.
To determine if you can Upgrade to megasquirt will be decided by if you can do wiring and how long the car can be down for. There are definite advantages to doing it though!

mark kibort

why cant we just adapt the 5 liter M5 BMW intake to our engines. Then, it could be used with a stock MAF on the S4 or other methods to control air flow metering. there woudl be an adapter plate needed as the BMW V8 intake ports are closer together, but i suspect that something could be fabricated.

I still cant belive no one has bolted on a high performance intake on a 928 (stock engine size)

123quattro

It's just not that simple. You can't run ITBs with MAF control. MAF isn't fast enough to see tipins and it will have lean stumble all over the place. WOT would be ok, but everything else would be seriously compromised. You need alpha-N control, which requires a full retune once the intake is on.

ptuomov

People have bolted M5 V8 ITB intakes on 928. Cheburator comes to mind.

You can run ITB intake with a MAF. In fact, that BMW M5 V8 with ITBs runs two MAFs from the factory! (It has fly by wire throttles, too, so in all fairness it's not ignoring the throttle position...)

There are bigger issues with the lean stumble, mainly part wall wetting and drying. That's why all systems, including carburetors and LH2.3 have specific features to manage the fueling when the throttle is opened. In the '87 928, LH 2.3 will look at at least the throttle position switch and squirts in more juice when you floor it, MAF signal be damned. [EDIT: apparently the last sentence is bull****.]

John Speake

LH2.3 (and LH2.2) accel enrichment works solely on MAF signal. That does require the MAF to be close to the throttle plate. Presumably that's why BMW used two MAFs - to get close to the throttle plates.

ptuomov

Interesting. Not the first time I've been wrong. Tell us more, how exactly does the LH2.3 acceleration enrichment work? I'd love to know. Is it a pure X-Tau algorithm? This is very relevant to me as I am trying to get the car to drive a bit better with the new map EZK grid.

The S62 in M5 didn't have the MAFs particularly close to the throttle plates. They are in fact pretty far away from the intake horns:

hacker-pschorr

Don't tell Ferrari they've been doing it wrong all these years.....

Same MAF the 5-series BMW has from the same time frame (1995 - 355's and 348's have two MAF's).

John Speake

Niklas did the analysis and code investigation of the acel enrichment. I don't know how deep he went into the algorhiym. We could have some 3 way discussion by email to hear about the issues you are experiencing... although Niklas is a very busy guy !

Cheburator

The stock V8 BMW airbox CANNOT clear the bonnet line of the 928.

I have fitted ITBs off a BMW M5 to a stock-ish sized engine, but had to play around with trumpet shape and size. Read what other people say, Kibbort! As a matter of fact, there is a video of my engine running with the ITBs in this very topic, on page 1!!!

mark kibort

i was thinking, loose the throttle bodies, and just use the intake horns and air box enclosure. that way, you use the stock MAF and solve 80% of the problem.

Or someone bolts on the CF intake to a S4 and we see what the intake optimization can do. the closest we have is the homemade intake but made for the blower application. (Carl's)

mk

Lizard928

Mark, I will be doing it on a 5L, but with boost.