Matts440
Well-Known Member
Mines just the summit brand one, if you were running 10an instead of 8an I have a spare close Y
7875 + 5.9 + E85 + Megasquirt
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Hemirunner
Well-Known Member
The Holley injectors work well for me and their 160s seem to be popular.
dusted
Well-Known Member
Subcom, was it Snake eater performance? I’ve heard there was another company claiming the be Snake eater injectors.
SEP - Snakeeater Performance in Hawaii
I’m still optimistic this deal will work out but the first impression isn’t the greatest and still haven’t got a response from my email to support.
Got a response from SnakeEater. Their only suggestion is that maybe I don’t have enough fuel delivery to satisfy these thirsty injectors. OK. But even at idle they run hyper lean?
So I decided to just tune them. Reset my required fuel, dead time, etc to match the 142lbs, added a bunch of fuel to the VE table to get it to idle, added 20% across the entire table to get it going, still too lean off idle. Add 20% more. Now we’re closer. Enabled the AFR short circuit so that it cuts spark if we go too lean while in boost. I get into low boost, it’s still lean, add some fuel to VE table, hit it again and we’re rich. Come home, pour over the logs. Although it’s really rich and I know I need to pull some fuel from the VE table what gets me is that the duty cycle is essentially the same as my old injectors with all other variables being igual; TPS, RPM, LOAD, AFR, FP, etc. it’s like 40% duty cycle at 6psi which was the same as my old 80lbs.
So I decided to just tune them. Reset my required fuel, dead time, etc to match the 142lbs, added a bunch of fuel to the VE table to get it to idle, added 20% across the entire table to get it going, still too lean off idle. Add 20% more. Now we’re closer. Enabled the AFR short circuit so that it cuts spark if we go too lean while in boost. I get into low boost, it’s still lean, add some fuel to VE table, hit it again and we’re rich. Come home, pour over the logs. Although it’s really rich and I know I need to pull some fuel from the VE table what gets me is that the duty cycle is essentially the same as my old injectors with all other variables being igual; TPS, RPM, LOAD, AFR, FP, etc. it’s like 40% duty cycle at 6psi which was the same as my old 80lbs.
Rat Bastid
Dunamis Metron
Got a response from SnakeEater. Their only suggestion is that maybe I don’t have enough fuel delivery to satisfy these thirsty injectors. OK. But even at idle they run hyper lean?
So I decided to just tune them. Reset my required fuel, dead time, etc to match the 142lbs, added a bunch of fuel to the VE table to get it to idle, added 20% across the entire table to get it going, still too lean off idle. Add 20% more. Now we’re closer. Enabled the AFR short circuit so that it cuts spark if we go too lean while in boost. I get into low boost, it’s still lean, add some fuel to VE table, hit it again and we’re rich. Come home, pour over the logs. Although it’s really rich and I know I need to pull some fuel from the VE table what gets me is that the duty cycle is essentially the same as my old injectors with all other variables being igual; TPS, RPM, LOAD, AFR, FP, etc. it’s like 40% duty cycle at 6psi which was the same as my old 80lbs.
Here goes something I have zero personal experience with but I just saw a video about something similar to this so take this for what it’s worth which is damn near nothing.
Last week there was a 2 day webinar called Engine Performance Expo. It covered all manner of topics, but they built a Pro Charged LS and Ben Strader of EFI University did most of engine specs and the dyno tuning.
I can’t remember the exact RPM they were going to turn the engine but it was at least 8k. Not that that matters much, but it’s part of the story.
Anyway, they broke the engine in NA and then installed the PC. They started making pulls and about 7k and up it started looking lean. So he added more fuel. It was still lean. And then more fuel. Still lean. More fuel. And still lean.
I also can’t remember how much more fuel he had added but it was a big number...like 120% more fuel and it was still lean.
So he decided to stop and really look at the data. What he found was the fuel system in his dyno room wasn’t capable of feeding the injectors so even though he was “adding” more fuel it really wasn’t because the pump couldn’t keep up with the demands of the injectors.
So there may be something to what Snakebite is claiming. I don’t have nearly enough experience with EFI to give even a little advice, but I thought it was interesting what I saw last week and it appears to mirror your situation. Or not!!! I just don’t know but it sure seems similar.
I don’t think the Expo from last week has been published to YouTube yet, but if you go to engineperformanceexpo.com you should find a link that will hook you up with both days of it. There should be separate links to all the various segments they did, or you can open up the entire 8 hour or so long link and scroll through until you see the engine the dyno and watch from there.
There’s some really good info on webinars like this.
I hope this may help you sort this out. You could even call Ben at EFI University and pick his brain to make sure I’m not nuts and wasting your time.
Rat Bastid
Dunamis Metron
I don’t remember if it actually dropped fuel pressure. I’m sure they were recording it.
TT5.9mag
Two atmospheres are better than one
@Rat Bastid i like Ben Strader, that dude is pretty sharp. Figured I’d drop a link.
https://youtube.com/c/EnginePerformanceExpo
https://youtube.com/c/EnginePerformanceExpo
TT5.9mag
Two atmospheres are better than one
Really it depends on what pressure the injectors were flow rated at. The industry standard is 43.3 psi or something like that but some companies fudge the pressure to make themselves look better.
I tend to agree. It’s seems I’m just flipping the math to get the same results. Less required fuel X Bigger VE table values for the 142s vs Bigger required fuel X smaller VE table values for the old 80lb injectors.
Working on placement of the dual AEM 400LPHs. Fuel starvation shouldn’t be an issue now. I mocked one up and ran it to make sure it could still lift the fuel a short distance since it looks like I’ll be placing them slightly above the sump outlets.
Got them mounted. As luck would have it the Y block has a tiny leak on one side. Everything else appears to be leak free. Still need a 2nd relay to drive the new pump, ans wire it to the MS3PRO.
Matts440
Well-Known Member
Looks great, bummer about the leak though.
goldduster318
Overzealous Car Modifier
If your injectors were large enough and the duty cycle went to 100%, you'd know you were out of fuel just by watching that. Had a friend send me a log from a sniper where it fell on its face at the drag strip and the injectors were at 100%. As I suspected the fuel system was not a good design (external pump mounted above the bottom of the tank, no return line, pulling through the stock sender). Having a properly designed fuel system is extremely important for any EFI system. If you didn't already have anything I would have gone in tank pump (like the Aeromotive drop in Phantom Dual 450 – Aeromotive, Inc ) if you were worried about it. I have the single Phantom 340 setup and it's been flawless since 2015.
Roughly 300 kPa, but you have to watch now because the newer vehicles like LS engines have 400 kPa/58 PSI rated injectors. Most injectors you can buy now (especially the thinner ones with plastic bodies like I run) would be fine to run at 58 psi line pressure if you were running out of headroom and needed some additional flow.
He’s already logging fuel pressure which would determine if the fuel system is up to the task or not(PLEASE correct me if I’m wrong!). He is running 58psi base fuel pressure on the old injectors and the new injectors. He’s drawing fuel from a welded on sump that may have it’s weakness’s, but only at very low fuel levels or when cornering. He’s faced fuel delivery issues in the past and I just don’t think that’s what’s happening here.
Subcom, in the past when I ran two pumps I triggered the second off a Hobbs switch at 10psi boost. However, I was running a stock fuel pressure regulator at the time that couldn’t bypass enough fuel. Hopefully going off throttle% works for you, but if not try triggering from boost pressure.
Subcom, in the past when I ran two pumps I triggered the second off a Hobbs switch at 10psi boost. However, I was running a stock fuel pressure regulator at the time that couldn’t bypass enough fuel. Hopefully going off throttle% works for you, but if not try triggering from boost pressure.
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I lowered base pressure to 43 which is what all of the injector data is based on. I do log fuel pressure and so far it’s not a fuel pressure issue with these new injectors. The 2nd pump is more for when I’m able to increase boost. My plan is to drive it off of a 12v output from the MS that I can program to trigger based on throttle position, RPM, target boost psi, etc.
Turbosmblk
Well-Known Member
Do the plugs show lean as well or are they drowned with fuel?? Plugs dont lie. O2 sensors do.
Turbosmblk
Well-Known Member
Also. If you’re running Edelbrock fuel rails If I’m not mistaken they are 9/16ORB thread which is 6AN. It can only flow so much fuel. Now granted that shouldn’t be a problem at idle like you’re having but once you really start needing some fuel I could see it being a restriction
goldduster318
Overzealous Car Modifier
The older Edelbrock rails like the ones I have were NPT, but yes, they are sized for -6AN. The other thing would be is if the fuel goes through a Y block and to both rails and then back to the regulator which bypasses to the tank. If its one rail to the other it seems a lot more likely to go lean on the 2nd rail.
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Turbosmblk
Well-Known Member
Good point goldduster. Ive always thought the best way was Y block to each rail then each rail to the regulator then back to tank.
Matts440
Well-Known Member
Thats how mine is, maddart changed it to this so it feeds all the injectors first then the hits the regulator and returns to the tank.
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