My current combo is #60 injectors, 212 / 212 cam, Champion Iron heads, TE-44, alky, etc. I'm pulling 118mph passes with 20psi and 21 degrees of timing, so this thing is making some decent power. Anything 22psi or more and I start to lean out. If I stick with 20psi my AFR holds solid as a rock. I will verify this with a fuel gauge this weekend, but I'm willing to bet that my Walboro 340 is not keeping up. So, if that's the case, what pump do you all recommend? I see Eric has a pump that is rated at 270lph. Is that enough? Mine's 255. How is the Aeromotive 340lph pump? Should I get a volt booster and see how that works out?
put a fuel pressure gauge on the car and verify,guessing can get very expensive.a 340 if working will handle 118mph gn
Like I mentioned in my first post, I will get a fuel pressure guage on it this weekend. I'm just waiting for it in the mail. The one I have doesn't have a long enough line to mount it on the windshield. Yes, its hotwired. I have the Racetronix kit on it. Maybe the pump is just weak. I should also check my logs for voltage drop under WOT. That could cause an issue as well. If my fuel pump gets a clean bill of health I will get my alky pump to Julio to rebuild, but at this point I don't think that hitting the limits of my alky system will make the AFR start to lean out quickly since the alky is functioning as more of a cooling / octane system vs. a base fuel source.
Because of the amount of alcohol required to kill knock and run 25psi on these cars, the alcohol becomes a significant part of the fuel curve. If it's not coming on, or not enough, it will go lean. My chips are set up assuming the controller is set to the recommended #6 on the dial (give or take). Eric
If you don't have an AC Delco fuel filter,get one. I've experienced a 6 lbs increase when my fuel supply was unable to keep up.The filter I had on the car was a brand new Purolator. Every one of our cars should have a volt booster. It will increase pumping ability and spark output. I like Red Armstrong's volt booster because he doesn't use the TPS to trigger it.
Thanks for the info Eric. I got the fuel guage and will check the pressure under boost by this weekend and know for sure. My alky system does need a makeover. I have the old style pump from Julio and it may be hitting its limits. I'm also using a Snow Performance progressive controller. I have it set to run the pump at full pressure by 25psi. I can set it to ramp up faster and see what happens. Getting my pump rebuilt and a Razor controller is on the list. Ttype6, I am using a AC Delco filter. I have used Wix filters with no issues. I won't use anything else. I attempted to make a volt booster based on this diagram: http://www.gnttype.org/techarea/projects/gnalt.html It runs off a relay that is activated by a Hobbs switch that triggers at 10psi. I tested the wire that goes to the S terminal and it read 2.2v less than battery voltage. I hooked it up to the S terminal and the 30A fuse I used to protect the circuit blew. Not sure what I did wrong. I hate to spend $70 on something that I already have all the parts for. I will go back through it, see if I can get it to work, and see how it changes fueling.
Which ever way you go,get more voltage to the system and your pump and ignition will benefit. Did you determine that your fuel pressure rises correctly?
So I checked fuel pressure at WOT. 64psi at 20psi of boost and holds rock solid. I ran it to 22psi and it held at 66psi. I went up to 24 and it hit 68psi, but I had to get out of it since it was starting to go lean. Looks like the meth system is my bottleneck. I'll be pulling the car apart for body and paint in a couple months, so I will send the pump off to Julio and get it rebuilt at that time. Until then, boost is at 18psi and the car runs just fine on the street. I'll leave the 340 in for now and go with a DW pump down the road if I decide to start playing with E85. I'll need to trade up my 60's for 80's too. Man, the snowball never stops rolling, does it?
You take the alky off and only have pump gas 18 psi is asking for trouble...your alky chip still will have the timing too high for pump gas as soon as you hit PE. Lower it to 15 or just resist getting into boost.
I didn't mean that I was going to take the alky off and still run 18psi lol. I'm not that dumb. I'm backing it to 18psi with alky. I'll send the pump in when I start pulling the car apart for paint. It will be down for a good 3 months then.
