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Reanimotion Reanimotion is offline
umop apisdn
Join Date: Jun 2014
Location: Brisbane, Australia
Posts: 501

The standard MicroSquirt firmware will not work to control the Frequency Valve properly.
The FV requires a constant frequency of around 100 cycles per second regardless of engine speed and an on/off ratio of +/- 50%, the staged injection is a timed squirt per revolution of the engine so the frequency varies with speed and the ratio is therefore too hard to control and too jumpy below 6000 rpm.
The FrankenCIS firmware has the fuel control required for both the FRV and eWUR and also does not need the eWUR at all if you are only interested in controlling the lambda circuit.

So start with FrankenCIS firmware from day 1, we've also written the firmware changes so you can switch the system between CIS modes and Normal EFI if you do feel the need to experiment.

regarding the lambda control
From post 423 in this thread
Originally Posted by Reanimotion View Post
Fasteddie313 has provided some very interesting test results

on a stock CIS-Lambda fuel distributor at full travel, driving the frequency valve at 100% duty added approximately 60% extra fuel over normal :: View topic - FRANKENCIS - microsquirt replaces WUR > UTCIS

So don't forget to connect the frequency valve to FrankenCIS if you have one
replicating the static tests Eddie did with your 930 would be fairly simple, and safer than with a running engine on the road.
Stock operating range is 15% to 90% on time - so short periods of 12v or 100% wont hurt.

The stock Lambda computer only has a limited range of activity and will disable itself under full load or extended marginal operation, so trying to fool the stock system would have the very high risk of the thing turning off at the wrong moment.

Also note the 044 pump and the stock CIS pumps have the same pressure and flow curves. The only difference being the different inlet on the 044 and the 044 is generally cheaper. There is a Bosch test results PDF link earlier in the thread, obviously a good new 044 might be better than a worn stock pump, but for the messing around I'd personally stay with a new stock replacement or change to the true 8bar motorsport pump from Bosch and not the 044.
1981 928S 4.7 ROW with KE3-Jetronic and Franken8 (AEM Inifinty) follow at []
Yes! mechanical/hydraulic constant flow injection can be managed by a modern EMS
Old 03-16-2016, 04:41 PM
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