Originally Posted by wreckleford

Here is an interesting article that brought this thread to mind:

http://www.adaptronic.com.au/fuel-pr...-a-difference/

Originally Posted by starkx2

Are the bottom of the threads on the damper to sit flush in the rail (not able to see the threads when looking through the ends) or do you just screw the damper in till it sits flush on the outside of rail.

Originally Posted by mrfred

Did you get the NPT version or the ORB version? Which rail? And are you sure you connected to the correct port on the rail?

Originally Posted by starkx2

Npt version, did the 3/8th drill and tap on the underside of boomba rail between 2 and 3 injectors

Originally Posted by mrfred

After I got my BBK-3B installed and did some tuning, I realized that my FIC1100s weren't going to be big enough for this turbo, so I went out looking for a bigger injector. I was looking for an injector that flowed about 20% more, but by an unexpected chain of events, I found myself with a set of new FIC2150s to try out in my Evo. My FIC1100s were dialed in perfectly with the LTFTs drifting by no more than +/-2%. I really wanted the FIC2150s to be dialed in this well, but my initial efforts led to frustration. The tables that I had used to dial in the FIC1100s weren't enough for the FIC2150s - I was missing something.

It didn't take much reading online to figure out that the FIC2150s flow so much that idle and cruise fuel requirements fall within the "partial opening" response of this injector where the fuel flow rate is very non-linear with pulse width. FIC has a great overview of this injector characteristic on their website. The ECU determines the required fuel pulse width assuming a linear relationship between pulse width and flow rate, so having idle and cruise in the non-linear region requires an additional table to accurately dial in these injectors. As I outlined in a previous thread, the Evo ECU (and surely any modern OEM ECU) has a table to account for the non-linear response when calculating the final fuel pulse width. For the Evo, the input for the table is the linear pulse width request, and the output of the table is an pulse width adder that is tacked onto the linear request to make the injector flow the correct linear amount of fuel.

I didn't want to try to figure out the correct values for this table completely by trial-and-error, so I got in contact with Jens and Dan at FIC to see if they could provide me with flow rate data that I needed to come up with starting values. After a bit of discussion, they provided me with exactly what I needed. The non-linear response of the FIC2150 is compared to the idealized linear response in this first graph. As noted, I found from my initial tuning of these injectors that daily driving takes place well within the non-linear "partial opening" region. For instance, idle takes place at about 0.55 ms.



From the graph above, I created a set of pulse width adder values for the table in the Evo ECU. The calculated values for the FIC flow data are shown in the blue trace in the graph below. I started these values, and after a bunch of street tuning, I ended up with the red values. The stock values shown in the plot are approximately half the values needed for the FIC2150s, highlighting why using appropriate values can make a difference. As indicated in both graphs, these linearization values have matched latency values that go along with them and are much different than the actual latency of the injector. I've listed the calculated and tuned linearization values at the end of this post. The definition for the pulse width linearization table is in my other thread on this topic.



Next is the injector scaling. In every post I found on EvoM about scaling for this injector, people settle on a value that is much lower than the value expected based on the flow rate of these injectors. I have found that 1170 cc/min (on E85) works well for me, so my experience is the same as everyone else.

As with my FIC1100s, getting best drivability also required tweaking the MAF scaling table. For people running MAF, this table is useful for dialing in closed loop trims, and it's what's needed to make the AFR table match actual AFR in open loop. The name given to this table by someone many years ago suggests that it affects the load calculation, but in fact, it only affects the fuel calculation, so its a very useful tool for tuning AFR. Most people running FIC2150s are running SD, so I'm not sure how useful it would be to tune the MAF scaling table because it provides a similar function to the SD VE tables. If anyone is interested, I have posted my values at the end of the post. Note that I have changed both the input and output values, as well as the scaling offset, and MAF compensation.

After getting everything optimized, I've found these injectors to have amazing drivability irrespective of their size. I have them idling perfectly at 875 rpm, and I'm sure that they would idle just as well on pump gas. Closed loop transient and cruise response are also great.

In summary, I have worked out what I believe to be accurate pulse width linearization values that anyone can use to help make FIC2150s work better in their Evo. This table can be used in combination with the injector scaling and latency tables to dial in the FIC2150s, but better results might be obtained by also tuning the MAF scaling table and/or SD VE tables.

Originally Posted by mrfred

The MAF scaling tables are not in hex units. For example, in the MAF Compensation table, just enter "128".

Originally Posted by letsgetthisdone

Stock rail and reg. FIC 1650 hi-z injectors and a walbro 450 in a modified stock sending unit with the siphon drilled to 9/64's. Stock feed and return lines. Car never had the lean spot before going to the FP red and big injectors.

Originally Posted by mrfred

word has it that radium is working on their own damper (vs their current offering which is simply a bosch damper). i will likely try it. a number of people say that a damper is not needed for stock rail and fpr. what you got?

Originally Posted by mrfred

I've got the data to build a PW correction table for the 1650s, and I've requested the necessary data for the 1100s. Probably won't have time to build the 1650 table until this weekend.

Originally Posted by cdrinkh2o

Mychailo - Can you email me the data for the FIC1650s? I have the low-z version and find that they are on the seat at the low pulse width required for a good idle on 91 RON. I also have the time and the need to build the PW correction table. Will post the details when completed. PM me for my email address.

Originally Posted by BiFfMaN

Just installed a Fuel Pulse Dampener today, Fixed my lean tip-in issue and Surge @ 2-3kRPM.

Originally Posted by mrfred

Which damper did you select?

Originally Posted by dr_latino999

Tested out the Radium inline damper today, their vacuum reference design, and it has completed removed my lean spots in my logs. Harmonics can suck it

With this combination - FP Red, FIC 1250s, Walbro 450, -8 Feed, -6 Return, FIC Rail, Fuelab Regulator - the damper has made driving so much smoother with no other changes. Before I was reaching mid 17s in my AFRs at steady state highway conditions uphill, now, high 13s as my map requests.