REW Sequential Dyno - very uncommon results
 

I figured I put this in the 3rd gen section as you guys would have the most interest in the project, results and have the most informed critism.

A quick rundown of what's involved here
13B-RE block and mani's. Rebuilt, cryo'ed and ported.
Intake ports were SMP med intake that I spent hours cleaning up the bowls and runners. Portmatched LIM to block, UIM to LIM
"Cosmo" housings with REW sleeves and I used the Pineapple Race EP2A template.
RX8 eshaft and stat gears
S6 rotors

Turbo's are bone stock REW sequentials run non-seq (for the time being, going back in a few weeks to get the seq working) with the exception that I had everything ceramic coated from Anthony Bulger - Street Tuner and I modified the y-pipe to elimate the stock bypass valve and my own efini style x-over pipe.

I built my own HMIC setup and modified the standard Greedy TB Elbow to suit my needs

Running a Motec M820 and using Rob Bailey solenoids to control the sequentials.

Running 93 oct, OMP injecting Idemitsu premix and running about 1/3oz/gal in the tank. After 2500 miles the compression is still rock solid and hasn't fallen off at all. It seems to get slightly better by maybe 1% so I believe the ratios are right on the money.

So, what are the results? I was actually VERY surprised. Using the Motec's datalogging we were running about 160-165kpa which is ~8.7-9.4 lbs of boost. Call it 9lbs. At 9lbs of boost running non-sequential but all of the sequential hardware in place Dave @ KDR and I made 328.88 RWHP with torque climbing all the way to 6800 and hp not starting to fall off until 7300. Current redline is set @ 7500. Pretty conservative timing and running .8L or ~11.7 afr.

http://rotarycarclub.com/rotary_foru...1&d=1254066817

And a vid



Has anyone ever seen numbers this high using the stock twins at that boost level? I have plans to go back to KDR in search of 400 RWHP @ 15 lbs of boost with the sequentials working. They'll work, we just need some time on the dyno to get them sorted out and functioning properly. The highest that we've seen was 402 with the stock twins. However, that was a half bridge motor running 18lbs of boost. The turbo's lasted 300 miles.

Those are really good numbers, especially for less then stock FD boost level. Usually it takes about 13 psi to make that kind of power with the stock twins, sometimes even more then that. Good tuning afr too. Right where you should be, not too rich and not too lean.

That's what I've found as well as what Dave has experienced. I'm heading back in a week or two to up the boost to 15lbs and see where we land. We're hoping it's north of 400 wheel and from his experience, and my research, we think it's possible. I'm very pleased. Now I'm left wondering exactely what did it? More than likely it's the entire package though.

I agree with you and Dave on the AFR's, 11.7 or .8L is just about as perfect as you can get. EGT's peak around 1700* with timing @ ~17*. It almost seems like she wants a touch more timing. There is about an 80* difference in temp between the front & rear rotor and regardless what we do it's ALWAYS there under full load. Cruise it's just about dead on but as load increases, so does the difference.

Yeah thats pretty conservative timing, could try a bit more and see if the power keeps going up. Once the torque stops increasing, or drops off then back it off slightly.
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You will always have the difference in chamber temps. The rear always seems to run a bit hotter. It seems regardless of the setup and changes people try, the difference is always there. My only theory is the water cools the front first and can't cool the rear as effectively, heat is more retained in the rear hense the temp differences.

Here is my take on it. 1st, every car that is dynoed at KDR has higher than usual numbers, this is not a knock on the shop at all but simpley every car I see dyno there has higher than usual numbers. Either he is doing something incredible no one else is doing or his dyno is generous, Ill let you decide on that. ;) Id be interested to see you dyno it at another location with the same type of dyno and see how similar the results are.

2nd, I made 295rwhp on 8lbs back in 02 or 03 and no one believed me. Auto/Manual swap car, stock ecu, 8lbs, sequential, full 3 inch exhaust with a carbon ti muffler, pettit intake, simplified sequential, greddy pullies and I think a pettit underdrive pulley but cant remember. I dont think I have had a car to this day that pulled like that one on 8lbs. Before I sold it I installed a pettit ecu and ran it on 14lbs(didnt know better back then) and I swear that car had to be making close to 350rwhp as it pulled like no other stock sequential car I have been in since. Some cars/setups just work better than others, sounds like yours is running good.

I accept that challenge. I've been witness to a ton of dyno's there and alot of them seem to fall where they should, some even lower than I would've thought. I'm inclined to disagree with the statement that EVERY car that's passed through those doors dyno's higher than it should. That's a pretty bold statement. Not to sound belligerent or like a prick but "every" is bold. We also overlapped a bunch of dyno's of other sequentials that had been there and they were all right were you'd expect them to be.

I'll admit, I'm curious though. After we get her settled to 15lbs I'll hit a local dyno. There's one literally 1/2 mile from my house. They have a DynoJet 424x. I BELIEVE Dave has a 242x. Either way I'm not going to be able to find a 2wd dyno around here. Too many scubi's and devolutions running around. When she's set to 15lb's I'll be able to trim the boost back with the trim switch on the dash. Before I leave Dave's I'll make one run @ 9lbs, and the last at 15lbs. That day or the next I'll head to one of the 2 local guys and make the same two runs and put the results here.

Thank you. Honestly, in my case, I'm inclined to think that it's the package itself as a whole. Everything that I've done to make things as effiecent as possible. All the ceramic coating, the porting, polishing, portmatching, HMIC, just everything coming together to be one really sweet well matched package. Of couse the insane tolerances and time spent rebuilding the engine didn't hurt either :rofl:

Looks good, but needs more torks. Dan Chadwick's car made similar power at those boost levels, but his torque is insane for a rotary. Of course his is sequential, but it makes over 200 ft-lbs at the hit of the throttle at 2500 rpm and well his torque curve is more like a plateau than a curve and I don't recall where we maxed out, maybe Dan will chime in with a dyno plot. Our results were still with a very conservative tune since we didn't want to risk blowing anything up prior to Nationals. Over the winter, we will see what it is capable of.

"Every" is bold, but his shop seems to put out higher numbers than what is usual/typical, like rx7store used to back in the day. This is in no way meant to be a knock on anyone or these shops, just saying, some dynos read higher than others. I would be interested to see the results on a dyno dynamics dyno if possible, it will likely be a awd dyno but you can still dyno your car on it.

He will pick up quite a bit of power down low once he gets the sequential working. Plus depending on his porting and such it might be sacrificing some torque for power on top.

I would like to see that dyno chart actually. I know you guys are running the '99spec twins. When these blow that's the route I'm taking. From what I understand those turbo's spool slightly faster than the 95- twins and generally make about 10hp more at the same boost levels.

I'm not sequential and before the 9lbs is reached I'm @ 200 ft/lbs. When I do get the sequentials working I'd like to compare them to Dans. You guys are also running the 9.7 comp S5 n/a rotors correct?

Yeah, the primaries are ported a little more than I would've liked them to be. I actually wanted to try these out with the RE on bone stock ports just cleaning up the runners/bowls and doing some port matching but that just didn't happen, I got too good a deal on the motor to pass it up. I would call it a med street port.

There is a shop about 20 minutes away that has a dyno dynamics dyno. I'll head there to get the other numbers and see where we lie. Why are you asking for a dyno dynamics and not a dyno jet? I would think for comparision we would want to see a similar dyno jet to see if it is that one in particular or just the really clean PA air.

Both the Dyno Dynamics and the DynoJet 424x are owned but the same family so the rates should be comparable, just curious as to your request is all.

Impressive numbers.

Correct.

I have seen very little variance in the dyno dynamics numbers, they read consistenly lower than what else is out there. I know it will read much lower than the dynojet but I can do the math on the dyno dynamics and have a really close idea to what the number equates to on a dyno jet. If you have another dynojet just take it there for a true best case scenario. Its not a big deal either way, but 330rwhp on 9lbs is hard to swallow on the stockers, I dont know if anyone has made that on the BNRs even.

also take into consideration that he is running an RE(correct?) and not and REW. which has significantly larger ports, and it is also ported. so he may be creating only 9psi of boost, but the engine has alot less resistance therefor flows more air. so that same 9 psi on his engine could be the same amount of air that a stock rew is using at 12psi...

I can't wait to see your seq. graph. The power IMO is very good for the boost and I'm thinking like others that the package is the key....power is all about how everything works together.

Truthfully though, I'm a little un-impressed with the 4000RPM numbers. My ancient T04-R slug and stock port S5 engine with low comp S4 rotors is cranking about 180whp by that point on wastegate (10psi) vs. your ~135whp. I would HOPE that stock twins, even non-seq, would be packing more punch down low. Thats not to take away from your achievement, that thing has a sexy looking graph. Also to that point though, if you were running 12-14psi non seq. you'd likely be at or surpassing my numbers by 4K.......soooo....

:)

This is the only chart I have of mine at the office around the same power level. This was at 10 psi:
http://rotarycarclub.com/rotary_foru...1&d=1254427639

Here is one at 13psi:
http://rotarycarclub.com/rotary_foru...1&d=1254427584

Non sequential twins with all the sequential stuff in place have horrible response compared to full non sequential and especially sequential. Years back i had poor mans non sequential and full 10psi boost was at 4k my t60-1 had 15 psi by 3700. And my t71 is slow as hell with 23 psi around 5k

That's not a rotary torque curve :D

Would you tell us more details about the motor?

Thank you!

Those are some awesome numbers. I wonder how much of that is from the higher comp rotors. I'd imagine alot of the torque down low is from it. Perfect auto-x engine isn't she?

I know it is, which was kinda the whole point to the tread.

These are the websites to the two local shops. I'm inclined to take her to ICS just because they have the dynojet, but I'll be more than happy to go to The Shop if you would prefer to get some dyno dynamics numbers. I'm curious as to what the "correction factor" is or what the math entails.

http://www.icsperformance.com/
http://www.theshopct.com/

13B-RE, RE housings, and 9.0 comp rotors. Renni E-shaft and stat gears, everythings been cryo treated. I rebuilt the engine using new corner and side seals. Side Seal clearance is 1/2 what Mazda min specs are, new Rotary Aviation Super Seals and race Springs. New oil control rings and MazdaComp springs.

Intake - we'll call it a Med street port. I spent about a day or more cleaning up the runners, bowls and portmatching the LIM to the block. The UIM to LIM is also portmatched as it is to the TB and the TB to the modded Greedy elbow. The TB itself got a little polishing and the 2nd'ary butterflies removed. Modded the y-pipe to remove the stock BOV port, seperated the chambers and built my own x-over pipe, much like Garfinkle did. Everything's been ceramic coated. HMIC, I'm not saying the name of the manufacture, but it is a damn heavy intercooler. 3" x 22" I believe.

Exhaust - RE housings ported with the Pineapple Racing EP2a Template and REW sleeves. I plugged the exhaust recirc port. El Cheapo DP with header wrap. Magnaflow 3" in twin 2.5" out presilencer and two Magnaflow 2.5" in/out cans. All sequential hardware intact. Ported the WG and ceramic coated everything.

Motec M820 ecu, 750/1000cc injectors, Cosmo pump, Aeromotive filter and Mini regulator......

Exedy Twin Disc Clutch, Torsen rear with 4.11 gears and 255/40/17 tires.

I think that's about all the pertanent info.

DING DING DA DA DA DING!!!! This is the exact reason I chose the RE over the REW. In reality they would've required the same amout of work to install them in my FC. I chose the RE becuase the UIM lends itself more for torque, the runners have more "balance" between them than the REW's LIM, runners are larger (which as dregg pointed out will move more CFM at the same boost level) and years and years ago when I was doing my research I was informed that the GZ LIM won't fit on an REW running twins and the whole point of this build was to stuff the best auto-x engine I could build into the chassis. End goal being a few dyno charts like Dans. Depending how far off I am, I may be finding a set of S5 rotors over the winter.

It's tough to get the non-sequential twins with all the sequential hardware to get to that boost level by those RPMS. @ 4k the boost really takes off though. I'm still messing around with the PID closed loop boost control. The Normal Position table seems to be the key to get good ACCURATE boost response. With the sequentials working though, I've played with them in the past on the street and at the blip of the throttle you'll hit 15psi by 2500 or less. It's crazy how quick that one Hitachi turbo spools up. I'm REALLY hoping to get the sequentials working at full tilt next Friday..... Spoke to Dave today, our next play-date is 10/09 so I should be able to get some numbers up by that night, charts a day or two later.

I agree, all the turbulence created by all the various flappers and butterfly valves does nothing good for the response, both on the exhaust and the intake side of it. On the otherhand, when they're in place and working......... holly cripes, retarded spool. Broke the tires loose on a little odulation in 5th gear @ 60 mph on the highway.

Thought I'd give an update regardless of how bad it was. We stopped early for fuel related issues and I believe there is either a boost leak, the Charge Relief valve puked, or something else with the turbos is wrong. It could possibly be I ported the WG too large and the backpressure is overpowering the WG Actuator. We stopped at 33% duty on the WG solenoid, 11.5lbs of boost and 360 RWHP, graph to come later. My fuel filter clogged again.

This is becoming too much of a habit so if anyone knows of a lab that can test my old filter to find out what is actually clogging it, I would love to know who they are.

Onto the screen shots, the dyno graph will come later. Trying to arrange my sched next week to get back to Dave after I re-double-check everything.

You can see why Dave let out early - she went a little too lean and heres why.

http://rotarycarclub.com/rotary_foru...1&d=1255158313

She hit about 12.5-13 afr and got there quick, kudo's to Dave for the cat like reflexs

In case anyone in wondering how much backpressure the twins really make, seeing how no one has ever been able to say definately. At 5k up the boost falls off. I think there's something wrong, valve, leak, whatever, something puked because I know I've seen higher creeps before, I missed something when I checked her over two nights ago.

http://rotarycarclub.com/rotary_foru...1&d=1255183282

Does the cosmo pump have good wiring? You're sure it's the filter clogged and not a sticking check valve or something right? You have a fuel filter sock on the pump right? Check to make sure it has the plastic things to keep it from collapsing on itself. I remember one guy's thread he was having trouble with fuel pressure dropping off, and it turned out the aftermarket sock he installed didn't have anything to prevent the sock from collapsing on itself, once he replaced it, his fuel pressure was back to normal.

Curious, where are you measuring back pressure for the twins? It's hitting 33 psi of back pressure at that point on the graph and it hasn't even peaked yet. That's pretty terrible.

The boost dropping off doesn't look like it's falling off a lot, maybe you need to adjust the solenoid gain, not sure what the motec has for adjusting boost, but most boost controllers need some kind of tweaking to keep it from creeping or falling. You could pressurize the intake system and check for leaks. I'm more inclined to think your engine is just breathing too well for the turbos, they can't supply the air that the engine wants. Based on the amount of power it's making at low boost pressures, it's requiring a lot of air. Twins usually start running out of breath around 14 psi or so, well you're using the same amount of air at 9 lbs of boost. You might just need larger compressors, just throwing it out there. It might be something else going on.

NIce numbers man! That thing should be a handfull when you stab it. Here is a link to a lab that tests fuels among other things.

http://www.intertek-cb.com/services/services.shtml

And a lab search engine I beleive

http://www.contractlaboratory.com/La...as_testing.cfm

Yeah, she definately gets up and scoots. Thanks for the links, gonna give them a call first thing Monday.

Yup, battery relocated to the bin, 25A breaker right there, 10ga wiring to the relay mounted on the shock tower and 14 ga to the pump itself.

Positive, after that last run we wheeled her forward, threw her on the lift and pulled the filter right there. We could barely blow threw it. Granted Dave and I are smokers but still. New filter went in and the L went from .8-.74. More flow/pressure = more fuel = rich etc etc.

Running the stock FC sock. Big square thing. Damn clean when it went in but I am going to check that, probably replace it as well. Whatever is clogging this up seems to have gotten a little finer as the 100 micron or so sock isn't getting clogged up but the 10 micron filter is. The ONLY thing left that hasn't been replaced or thouroughly cleaned are the lines themselves. I replaced them with -6 stainless lines. The last time I had the tank down I emptied a car of carb clean into the lines and then blasted 135psi of air through them. It took a dozen times or so to empty the can.

I'm measuring backpressure in the mani itself. Dead center between the two exhaust ports. We're seeing a max of 275 kpa which is 25psi. Where are you seeing 33psi?

The Motec has two ways of controlling boost. A PID function where you enter duty cylces into a Normal Position Table which the ECU looks at first then compares the Actual Boost to the Aim Boost and corrects the duty cylce accordingly. The PID needs the normal position table to be pretty accurate otherwise it hunts all over the place. I have a few logs where the Normal Position was close but the duty cycle would fluctuate between ~30 and 70% across the RPM range to hold boost.

While on the Dyno we were using just an open loop, we input the duty cycles that we want it to see and it does it. So we could easily reduce the duty cycle. We were at 33% before the fuel psi problem struck so there's a bunch more than we can take out. I MAY have to do a different actuator. I hear there is one that is about the same dimensions and has an adjustable spring, from the factory.

Thanks for all the help man, I really appreciate the insights. Having an engine that flows too well isn't exactely a bad problem to have. Of course then the question becomes do I just leave these turbo's alone where they are or do I do something crazy like a twin GT28 A-la Howard Coleman setup. They won't have the response of the sequentials unless I go all Mad Scientist with wastegates and tubing to make my own sequential system, but they will deliver the air for 400 RWHP..... decisions decisions.

I'm going to check all the valves and make sure they are not only fuctioning properly but are setup correctly in the software. Last night driving home I was checking Fuel PSI by making a few long runs up to 7500 while @ 0", I could hear a whooshing sound coming from the right side of the engine, at least I think it was, I'm thinking the Charge Relief Valve is pinned open, setup wrong, or the vac lines are wrong and that thing is just pinned open venting boost pressure. That would be a major leak to say the least. But like you pointed out, there is a TON of backpressure and not much boost. I know I've seen 15 psi higher in the band with less duty. So after I check that thing out I'm going to be pressurizing the entire system to see if there is anything else leaking.

Found the answer to one of my problems - the Charge Relief Valve was setup improperly - entirely my fault. 7 keystrokes on the Motec and the problem was solved, figuring it out though was an entirely different problem. Inj 7 is the CRV, notice in the second screenshot above the duty cycle is 0%, the one below it is 100%. 100% shows the valve boost and it stays closed, 0% shows it vac and it is held wide open. So in otherwords the turbos spooled slower than they should've, vented a significant amount to atmosphere, still made 11.5 lbs of MAP and 360 RWHP. Tonight I took a little trip and datalogged a 3rd gear pull. Note the boost level and more importantly the Inj #5 duty cycle. Inj5 being the WG. So, onto the fuel clogging and then back to the dyno.

http://rotarycarclub.com/rotary_foru...1&d=1255229030

Good glad you got that sorted out. You should see some more power now too. This is what I used to convert kpa to psi which shows 275 kpa being nearly 40 psi. http://www.csgnetwork.com/presskpapsicvt.html

Ah, 275 kpa is about 40 psi, but that is including the 100 kpa of atmposphere. Car off, key on, the MAP and the EMAP are @ ~100kpa. So that 275 kpa is really only 175kpa of internal exhaust "boost" or about 25 psi @ about 12.5 psi so it's a 2:1 at the higher revs which is right about the limit of where you want them to be. Anywhere from a 1:1 - a 2:1 ratio is generally acceptable. So when we get up towards 15psi it'll be interesting where they go. Honestly I think she'll exceed the 2:1 ratio and max out the 3bar MAP sensor I have for the EMAP

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.

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 :D 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..... :001_005:

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

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.

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.

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.

:D 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.

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

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.

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

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?