Puffwagon

Yeah I'll look into it, I've gotta up-spec the whole system if I want to make more power anyway. The swirl pot is mostly there, it has about a third of the base removed to accommodate the pumps. Last time I had it out I noticed the pumps weren't 100% level but cbf fixing it at the time. I've got the 40 micron filter in there at the moment, I'll take a look at it because the car did sit around for a while.

Jumping back in here for some info. I put my ethanol content sensor in the return of my car, thinking that it would always have plenty of return. I've noticed it moving around at WOT which seems like it is running out of pump. I'm gonna pull the pumps out and make sure they aren't on the bottom of the pot and also invest in a fuel pressure sensor.

I've got the bare minimum on there now to safely adjust the fuel and boost and it's gone from 18 samples per second for the final spark number to about 55 samples per second per channel. I'll take it for a drive tomorrow and see how it goes.

Cheers, that's handy. I had a look at the picture and there are frig all samples in the histogram. I'll go ahead and remove the unnecessary items and make load high priority. So do you think the reason it is showing varying numbers is because of the logging rate? Perhaps it is hitting a different number occasionally and because the logging rate is low, the average is highly variable which shows up as a variance in the chart? That might explain why I get some weird numbers in Virtual Dyno lately.

I couldn't trace the good chart, the log was too long. I traced the timing dip and it looked as expected, flat across the bottom of the timing map. While I am curious as to why the timing is moving around when it is showing it referencing the same timing cells, I figured I can make it stay flat and do what I want by adjusting the axis like this.

This is with load added into the charts, same pics

Sorry I should have clarified that too, I am logging the actual load, it just isn't in the chart. I'll trace it and see what happens.

Maybe. Dashpot is used for a nice return to idle. Read some stuff here, you can usually download trial versions of aftermarket ecu's with base maps, which are a great learning tool. They sometimes have manuals with them that help you learn to tune.

Could be a subtle variation in fuel pressure?

Here is the example; The only difference in the tune from these log pics is me smoothing out the boost curve via the wgdc table and a small sd table change to fix the lean spot just after 161 seconds. The timing maps are unchanged between the logs, in the first pic the line is still 19 degrees and the dip is 14 degrees. I didn't rev it out as much after I fixed it but you can see that the timing hadn't dropped off while at WOT. I lined up the blue line for reference.

I have my vehicle running the custom os, extended tables, 4 bar boost sensor etc. My timing tables axis max load is 2.6 whereas I will hit 6.0 load in the log. This works fine for the most part however I've noticed that if my boost control isn't spot on it will go into other load ranges, 5.7 etc etc. This is all very normal except I've noticed that my timing will have a dip or vary if I don't have a near perfect boost curve. There must be some sort of extrapolation going on, the only other thing I can see causing the variation/dip in timing is the wg pressure trending downward.

If you're worries about poor fuel quality here's some info; An engine can still knock with very low timing, running 91 will give you an idea of how much timing it will take, maybe 4 degrees or so at stock boost levels, then you need a safety after that. To be 100% safe you would let it remove enough timing to get it down to 0 degrees or slightly less, ie -2 degrees. You really need some kind of warning system that something is going wrong, wideband at a minimum, preferably boost as well, have the knock sensors working, iat table at stock settings and have boost safeties in place. Providing you stay away from the ragged edge you will have some more leeway there before things go wrong.

You can change the amount of knock it can take out, have a look through the various knock parameters and compare a turbo file to get an idea of what's in there.

The track at Mallala has e80, might be a bit of a hike for you tho Roland.

The quotes are to help with the stoich change. Either change the stoich value or change the slopes to run E85. A built motor will want about 18 degrees total timing but a stock motor isn't as strong. Considering you can run 13 degrees of timing at 13psi on 98 with a stock engine, you can decide how much timing is safe for your engine.

That clip is cut too short to see much but glad you got it sorted. Haha I was getting worried that my own dual 525's were going to run out 🤣 I've been looking for another gauge to add, I've got the advanced ethanol gauge but need one like the other one you've got there. Will be adding that in future to track oil and fuel pressure in the log.

So it's working now?

Have you run it up again?

Let us know how you get on, I've been thinking about dropping my base pressure to offset the injector pressure at high boost levels but haven't tried to yet.

I have used the Ryco filters but I swapped to a washable stainless filter from Goleby's. When the pump is running out but the injectors have room, you can add fuel to the speed density table. If it starts going lean at 5000rpm, get in there and drop the cells it runs through at WOT by 500 to 1000 numbers from 5000rpm and up and it'll richen up. I haven't tried dropping the base pressure but it should be as simple as changing the slopes and breakpoint to suit.

Let's take it one step further and say you shouldn't even touch an ignition map, unless you either have the experience to know what it needs or are using knock detection equipment. Now where's a big stick and a dead horse?

Haha yep the list is never ending!

Info from the Walbro site says a 525 is good for 100gph/378Lph at 78psi, the Raceworks calculator says the engine needs 359Lph for 700hp. While myself and others have made over 500rwkw with this pump, undoubtedly with falling pressure and near zero return flow, I think we're seeing some data show us that the pump is only stable to around 450rwkw.

A 460 and a 525 can also suck the pot dry pretty quickly if the fuel level is low. Fill the tank to the brim and see if it helps.

Is there a split in the fuel line between the pump and the top of the pot?