I am looking for any info regarding the new AEM 320LPH fuel pumps that are e85 compliant. I recently ran into issues of not having enough fuel when I switched over to e85. I upgraded the feed line to -8 and the pumps from Gen 1 GT supercar pumps to the new ethanol safe AEM 320 LPH pumps. While on the dyno with the stock feed line and GT pumps in an original Fore hat I was dropping fuel pressure around 5000 rpm....they were working for all their might and just didn't have enough even with the dual FPDM's and BAP running full on. Since going to the -8 feed line with a super high flow Fore fuel filter, I think the AEM pumps should be enough to finalize the tune. However, I've been told then can be a bear to tune, so I'm looking for info/feedback from anyone that's been there, done that, and would care to share their experiences. Some folks say they don't play nice with pulse modulated fuel systems, other say they are not an issue. I called AEM and spoke with a tech guy there and he said this "although we've not actually ran long term durability tests on those pumps, we know that allot of them are in use on returnless systems, and we've not heard about any failures due to being pulse modulated." He then went on to say that they are in the process of building a test bench just for the purpose of testing pulse modulation on their pumps. He said that there are some pumps out there (some of the larger Walbros) that flat out don't work as pulse modulated, but as far as the AEM pumps are concerned, they cannot say that any of theirs are known to be this same way. SO...for anyone looking to go to a larger pump for a returnless e85 system, stay tuned, I'll know this Wednesday if they will support 700+ WHP.
Honestly though, it wasn't near as much work as it sounds. I used a hand saw to cut the barbs, my grinding wheel to smooth down the edges, the brush side of the wheel to finish them off. I spent more time cutting hose to make it fit just right then anything. It too several attempts at putting the hat back in the tank to see if the length was right, but otherwise it was cut and dry. One other thing I didn't mention was that the pumps are too large in diameter to fit in the piece of the hanger that holds them securely. To fix that I stuck it into a Bridgeport and bored the holes out about .075"....this gave me about .005" extra wiggle room in case I want to use an even larger pump in the future. I drilled in a set screw into each side to secure the pumps even more because of the extra space. The hoses do a fine job in holding them in place, I just wanted some extra "hold" because that's the way I roll. All said and done I didn't have too many road blocks in making them work. I will say this about the pumps, they really do flow a ton of fuel compared to the GT Supercar pumps. The dyno session before this most recent one was the breaking point for me to have to upgrade the pumps. I was at 100% duty cycle around 5k rpm and leaning out. As stated before, I never saw 50% duty cycle on any of the 13 or more hits I made on the dyno Wednesday. In fact, my 80's are at 86% duty cycle, so going up to a larger injector will be the next fuel related move I make. I was bound and determined to make 700 rwhp on the returnless system, and I did it. Today was the first time I got to actually drive the car on the road since getting the tune done. I am here to tell ya, the car is a complete ANIMAL! I made several 3rd gear 30-130 mph hits....the car squats so hard in the back and just pulls like mad!! I freaking love the VMP blower so much more than my Whipple car....this blower does NOT fall off on boost! I literally stared at 18.9 psi, and ended the pulls at 18.6 psi....that's bad ass IMO. My Whipple would drop off a couple of PSI every time, and the power delivery was not near as smooth. my torque graph is SO damn flat from 3100-5400 RPM you could shoot pool on it. I was making over 600 lb-ft of torque from 3050 rpm to 5300....got love them that diesel like twist.
