REW Sequential Dyno - very uncommon results

[dudemaaan]

Greddy makes a fairly inexpensive 4 bar map sensor. It's what i'm running. Uses the same connector as the stock 3rd gen too which was nice. Price is around $116.

[TitaniumTT]

That's not bad at all actually. I don't know if we'll need it though. It seems that the pressure peaks and holds around 2bar of "boost" pressure.

So Dave and I have another play date 10/20, as in about a day away. Cars running great and boosting about 12-13 psi @ 60% duty cycle.... so she's still holding more boost at less duty which is awesome. I have a new AIT for the charge pipe so we can actually see what the temps are like. Going to install that tomorrow as well as give her a full compound, glaze and wax treatment. Figure she needs to be pretty for her date.

Hopefully I'll have interesting numbers to report back. Doing the math out again lands us just north of 400RWHP @ 15lbs.....

[dudemaaan]

Awesome glad everything is sorted out with the boost. Hope you reach the 400+ goal, looks good so far.

[TitaniumTT]

So, Dave and I had a playdate today

402.77RWHP @ 13.75lbs of boost running .85L. In Daves words, "we didn't tune for it, but she gave it to us" Shooting for .80-.815 but she went lean again, quick rundown of the days events.

Got her strapped down and we rocked through the cleanup making improvements and upping the boost little by little. Then on one pull she went a skoche lean on the top. Nothing alarming, but enough to raise an eyebrow, .82L I think. So we decided to smoke a cig and let her cool for 10 minutes and then go for the big 'un. On our break I mentioned that we should check the FPSI again as that last run kinda concerned me as none of the previous moved at all from the target. Dave agreed and when we checked the logs, the PSI dropped off again towards the top - MOTHERFUCKER!!!!!!!!!!! I've got the FPSI displayed onthe dash and after each and every run Dave would take a peek and they would ALWAYS go right back to 36psi, right where they should be @ idle, just isn't flowing enough up high though.

So we wheeled her forward, up on the lift and 10 minutes later the new filter was in, I never leave home without one now, how eff'ed up is that. Blowing through this was was laborius but not like the last one. The last one also was allowing 38psi through and the one today let 45psi though. So with the new filter in we strapped her back down, made a pull, cleaned a few things up, made another pull and on the 2nd pull with the NEW FILTER IN the psi dropped off again to 49psi when it should be at 55psi. So, I'm going to pull the pump, send that out, replace the sock, get the filters tested, and sleep in my garage with a loaded 12ga semi-auto Benelli and my German Shepard. Dave is convinced someone is pouring shit in my tank, the filters are coming out with a blackish tinge to them.

So it was bittersweet.... there were no congrats, no hi-fives, no bottle of Single Barrell Jack to be passed around just pissed off even though we broke 400hp on a set of stock REW twins, with another pound to add. I think that's a record though. I know there was a guy in jersey with a white FD, running a 1/2 bridge or full bridge making 402 but pushing 18 psi. The turbo's lasted 300 miles IIRC. We're happy, but not at the end just yet.... DAMNIT. And we REALLY want to play with the twins. We're using duty cycle control, 50% across the board but the solenoid doesn't activate until 120kpa, so every time we up the boost, we're upping it across the board and down low. On the drive home tonight I broke the tires loose in 2nd around 5500rpm with 3/4 throttle. The girl is PEPPY!

On the plus side I finally got a fast reacting AIT sensor from Motec installed. I wanted to get the one from dudemaaan but without knowing the calibration table, it was unknown if it would work. Regardless... when boost hits the AIT on the charge pipe pre-intercooler go from 108*F to 245*F and the AIT going into the engine go from 77.2*F to 80.6* That was on the 403RWHP run.... SICK!

So, anyone know of a really good but QUITE aftermarket pump that can flow at least 4000cc/min @ say 80psi? I own a Bosch 044 but that thing is LOUD.

[dudemaaan]

yeah dual FD pumps will flow what you need with very little sound. Congrats on the power, hope you get the fuel pressure sorted out. Seems hard to imagine someone repeatedly pouring something in your tank. Maybe you should get a locking gas cap. You still plan to run it on another dyno after you get it all tuned?

I know the joys of breaking tires loose at crazy speeds. It's fun but actually not as much fun as hooking up and feeling the acceleration. I broke the tires loose in 3rd today at 85mph on my low boost setting (15 psi). Car started going sideways. I really need to get wider tires.

[TitaniumTT]

The cosmo pump SHOULD be able to flow enough, dual pumps may be the ticket though..... I dunno. I think I need to wait until the lab gets back with what is actually clogging my shit up. I can't see it being epoxy residue in the lines, the "new" tank has been in there too long. I can't see it being silicone residue left over from the first tank for the same reason. The only think I can think of is some asshat is trying to sabotoge me.... honestly, clogging a filter in 600 miles and then another in a few short minutes?!?!?! Although that lends itself more towards a pump puking or a sock being clogged. I dunno.... but I'm getting pissed.

Tires coming loose @ 85 is sketchy. Did that with my old tires on and it scared the hell outta me. By 5500 in 2nd they're gone now though. I need something a little wider and stickier as well.

Yes, still planning on driving the 1/2 mile to ICS to use thier dynojet 448 for two runs, a low boost and a high boost just to compare them to Daves. I'll do it the day after we're done so the weather is about identical. Just need to get this fuel issue resolved though. It's killing me.

[Trout2]

Apexi BNR33 fuel pump should do. If you run constant 12V to it, you can hear a hum at idle - not obnoxious noise like some.

Jack

[TitaniumTT]

Thanks for the tip. It looks like I may need a new pump afterall.

I'm still not having any luck finding a lab that can disect a filter. Everyong can do a fuel sample, but not a filter. I know the contamination is in the filter, not sure about the fuel.

Anyway, an excerpt from my build thread -

Pulled the pump and hooked up a wire to both the ground on the hanger and the hot on the lid. Checked Bat voltage - 12.12V. Turned the pump on and probed those two wires so I could get a reading of what the pump was seeing with it in fuel and running - 11.12V. Not bad but still something not 100%. I've got a 10GA wire going from the bat to a 20A breaker like 6" away, and then the same 10GA running to the relay on the shock tower, and then 10GA running to the connector which I replaced with a weatherpack. So there is stock wiring from the connector to the pump. Not much but it's still some.

Next I hooked up an Ammeter and ran the pump. 12.51A. This is not good. It should be around 8-9A. This is interesting. I jumped the ground directly to the battery and got the exact same A reading. OK, so it ain't my wiring although there is a loss somewhere, most likely just the resistance of the connectors, breakers, relays ect ect.

The sock looks a little meh so I pulled the sock to eliminate that as a source of vac and got a reading of 12.46A. OK, so a questionable sock only adds a slight amount of resistance. This is interesting. Questionable meaning you pull the thing out of the tank and fuel is still being held in said sock.

OK, well, maybe that filter really is clogged. I'm still seeing ~ 43psi with no laod, but what if it isn't? That's a TON of A's for a pump to suck down. Alright, we need to know without a doubt that this filter is fucking me. So what do I do you ask - go on, ask. Alright alright, I'll tell you. I have a spare 250psi sender that I use for my comp tests. I dug through my binS worth of fittings and found a -6 male to -6 male with an 1/8"npt port, an 1/8" to -4 fitting. A -4 female to -4 female hose, a -4 to 1/8"FNPT and put my sender on the end of that. Then I got a coupler and spliced this hodge podge contraption between the hardline and the filter BEFORE the filter. The sender happens to be the same as my Oil Pressure sender ('cuz I get ~ 125 psi >3500) and turned the pump on. Read 43.2psi at the regulator. A little high. Even more interesting is that it read 42.6 - yes Forty-two and 6/10 psi BEFORE the filter. Interesting. There is a negative pressure drop across the filter. This could be because of a few things. The Fuel PSI sender is a 0-100 psi unit so the resolution on the 250 psi unit isn't nearly as accurate becuase they are using the same 5v. There is also some sender accuracy, -4 line for the prefilter and a few feet of it, -3 and 10" of it for the after filter plumbed intot the reg. I don't know what the acceptable sensor variations for the autometer (Delco) stuff is but it's OEM so it should be pretty damn accurate. So....... interestingly enough it appears that the filters are only partly to blame. I think the Cosmo pump that I've been using just isn't up to snuff for the pressures that I'm asking of it and the schmeg that was pumped through it in the beginning. I'm going to borrow my buddies Walbro tomorrow and toss it in and do the same tests. I know that the Walbro 392 HP draws just ~8A at ~57G/hr @ 12v. At the highest pressure I'm asking for it draws ~<9A and flows about 52G/hr @ 12V. At 13.5V it should flow ~62 Gal/hr. Assuming 100% duty cycle I need 55G/h. So the Walbro 392hp will actually definately work for me.

(edit - although it's noisy - I'd rather have the Apexi that Jack suggested)

The Cosmo pump has been tested to put out 66 G/hr @ 43psi @13.5V HOWEVER, it was never really designed to put out the kinds of pressures that I'm asking for. I wonder if the pump isn't just falling FLAT on it's face on the higher levels of PSI. Also, this is with a filter with 150 miles on it. I know for a FACT that I have had outright clogged filters and socks from the epoxy coated tank. I wonder if all the shit that went through there didn't fuck up the pump itself. Also, lets not forget that the pressure that I was getting before the filter was never recorded until now. It's possible that the line pressure got into the 80's. The pump way overworked got hot and FUBAR'ed itself. All sorts of shit could've happened but the Cosmo pump that I have, just isn't up to snuff right now. That's also evident by changing the filter yesterday, making one pull and on the second it just went to shit. We spent probably 3 hours on the dyno making pull after pull after pull. It's entirely possible that a questionable the pump "heatsoaked" if you will.

[Trout2]

From what I've read around the internet and experienced. The Nippendenso pumps do not last very long when running battery voltage. I ran an Rx7.com/Nipendenso pump for a few years through stock wiring then wired it up to the battery for constant 12V when I did more upgrades. Within a year it failed (started dropping pressure at high rpm's).

Jack

[albertomg]

Congrats on your amazing results.

Rich/Goodfella has a good write up on fuel pumps on the other forum in the Archives.

What are you using for a fuel filter? Stock or some kind of aftermarket K&N? Have you ever dropped the gas tank and cleaned it out or at least inspected the inside?

[Double_J]

Did you find out why you were having a FP drop? I too was tuning my car on the dyno, and all of a sudden my FP dropped. My car was running with a new supra pump, and filter. I would love to hear what happened to your car as I have not figured mine out yet.

[TitaniumTT]

Originally Posted by albertomg

Congrats on your amazing results.

Rich/Goodfella has a good write up on fuel pumps on the other forum in the Archives.

What are you using for a fuel filter? Stock or some kind of aftermarket K&N? Have you ever dropped the gas tank and cleaned it out or at least inspected the inside?

I was running a Marren replaceable/washable stainless steel filter. I changed that out for a much larger Aeromotive filter and datalogged the pressure differences. There is less than 1psi drop across the Aeromotive. The Marren was higher even after cleaning it. I'm currently running the Aeromotive.

The tank was in excellent condition. I cleaned it by hand as well. The contamination wasn't in that tank.

Originally Posted by Double_J

Did you find out why you were having a FP drop? I too was tuning my car on the dyno, and all of a sudden my FP dropped. My car was running with a new supra pump, and filter. I would love to hear what happened to your car as I have not figured mine out yet.

I did, it turned out to be the wiring afterall. What was happening was the wiring was getting hot on the dyno after all the abuse it was taking. 57psi run after run after run after run and eventually the wiring would get warm, causing resistance, causing the a drop in voltage causing the pressure to fall like a rock. It was an unfortuneate set of events that basically started @ DGRR '09. Anyone with me witnessed me testing the first filter by pouring acetone and fuel into the filter and having the filter hold it like a cup of water. After that and popping an engine on the dyno from a clogged filter I was convinced that was the problem even after it was solved which is why I kept on chasing contamination and bad fuel pumps. In the end though, after I replaced a known clogged filter and a known bad pump, the problem persisted (although it was taking MUCH longer to show up) and we finally found it to be the wiring. Basically Dave and I were running the car and as soon as the problem showed up we tested the wiring - WHEN IT WAS WARM - found the voltage drop, jumped it from the battery and the problem was gone. So we jury rigged some wiring till I got home and could properly strip everything out and run some marine 10ga wire. Haven't had a problem since.

Lesson being, if you're chasing your tail, theres a good chance that there is no problem to be found were you're looking.

[Double_J]

Interesting.... I should have given a bit more info. My engine was rebuilt and running fine. I had brought it in to have new BNRs put in. While there I had them do the fuel pump mod. After it was completed it went on the dyno for a tune. The car was running fine did 4 or 5 runs then all of a sudden it went lean like you mentioned above. They stopped tuning made some adjustments to the car and hooked up a fuel pressure gauge. Tried again and you could see the pressure drop right off at transition. They stopped and we went over the list of parts on the car.

4000km ago the engine was rebuilt, a new supra pump, and fuel filter was put in. They figured it must be the stock FP regulator since every thing else was new.

We put it back on the dyno and things were going well. We picked up right where we left off and did another 4-5 runs then bam it went lean again. This time the car sounded different, and it had lost vacuum. So it was torn apart and rebuilt. It looks like my seals had slightly warped.

There are only a few things I can think of that is causing my FP to drop. My pump, stock FP regulator, fuel filter, wiring, or the fuel temperature sensor - not even sure what that thing does.

Is it possible that I got a bad pump, yea. Is it possible the FP wiring job is not good, yea. Is it possible my fuel filter is plugged, not sure. The shop gave it back to me and I drove it home 500km without incident. Of course I was not pushing the car as I am now breaking it in again. Some people say do disconnect the FP temperature sensor since they do not know what it does and they do not use it.

Do you have any suggestions or how would you go a bout attacking this?

[TitaniumTT]

next time the thing goes lean on the dyno measure the voltage at the pump with warm wires. Or, completely rewire it with new 10ga wires and ground the pump directly to the battery and see if it happens again