LSA Supercharger on LS1 - How am I doing?

[zbls2121]

There are a few folks/places selling adapter plates. They are by no means the "right" way to make it work, but they sure are the easiest and fastest method, as well as cheapest! It does (I feel) cause some tuning issues as the weird port configuration with the adapter plate and the injector aim through the plate and the cathedral style head is blah at best. You also must be very particular about gaskets and tightening it down as there are no dowel pins on the cathedral style head to mate with the blower. You could get fancy and make something I suppose.

The bonus, if you want to think of it that way, is the blower is now .5" or so higher off the lifter valley cover. This means no issues with the 4 port steam line setup like on my 2000 LS1 f-body engine.

[AutoWiz]

Sounds like a set of ls3 heads would be quite the upgrade in the future.

[gofastwclass]

I'm using LS3 heads on a 6.0 iron block and it works well, but I'm at 88% duty cycle on the injectors at 2PSI. Time to go shopping...

[zbls2121]

Well, I installed my fuel filter and still had the same severe fuel pressure drop. I decided to investigate the fuel pump wiring as it is an older vehicle. I found a large (2+VDC) drop on the positive circuit for my fuel pump. I went ahead and ran a new wire/relay for the fuel pump with a 10ga wire (plenty!). Positive fuel pump circuit voltage drop is now at 0.260VDC at 75+psi and negative side at 0.04VDC. Made another log, found my fuel pressure drop is much less severe that before the re-wire, but still significantly falling off at the end of a 4th gear pull (see pics) first pic is before pump rewire, 2nd after rewire.

Some more troubleshooting in my future.

Fuel Pressure Pre ReWire 10-15-2016.JPG
Fuel Pressure Post ReWire 10-15-2016.JPG

[gofastwclass]

What type of pressure are you trying to run?
What fuel pump are you using?
Maybe the pump can't supply the volume you need at the pressure you're trying to run.

[zbls2121]

I am running an Aeromotive 340 Stealth. 10ga to the pump (at the top of the tank). -6an supply and return lines. Aeromotive A1000 EFI regulator with an Aeromotive 12311 10micron filter.

Base pressure at atmosphere is 58psi (400kPa), 1:1 vac/boost referenced. Roughly I should have 48psi at warm idle, 58psi crossing into boost, and 68psi at 10psi of boost. Have yet to see it hold pressure. It has improved since adding larger gauge wire and removing the voltage drop. I checked the regulator reference and it responds perfectly.

I know the runs in the pictures above show I am still very rich, even more now than before as the pump can flow more with proper voltage. I think that puts a lot of strain on the fuel system, putting the injectors at a PW that is dumping fuel in with a fuel system that has issues.

This was done at 3/4-full tank of fuel.

EDIT: With the remaining voltage drop I can't measure (inside the tank etc) and the overly rich lambda during that run, I may just be at the limit of this pump at 68PSI. Just looking at the quick plot Aeromotive supplies with the pump; at 70psi in ideal conditions (13.5v etc) the pump is expected to put out roughly 250lph. That's 31.25lph/cylinder (or 49.58lbs/hr per cyl). The stock LS9/LSA injector is rated at 52.4lbs/hr at 58PSI or roughly 56.5lbs/hr at 68psi.

Either my math is way off (pretty likely!) or I am very under pumped?!

[gofastwclass]

Interesting... You have all quality stuff but something still seems wonky with your fuel delivery. Almost seems like your regulator (or the pump internally) is bleeding off pressure before it is supposed to. Just an idea.

[AutoWiz]

So the thing about a lot of -6an fittings is they are far from 3/8 i.d. And in fact the pretty aluminum anodized fittings that we pay the most for are simply the worst. And really it makes perfect sense when we think about it. Aluminum is a softer metal. If you want to use it for fittings well it needs to have a greater wall thickness. Take your an fittings out and measure their id and see how they are less than 5/16" i.d. if you must use aluminum an fittings you should really shoot for -8 just because of the id at the aluminum fittings. If you can setup and log fuel pressure between the pump and first -6an fitting you might find your problem.

[zbls2121]

Yeah, that thought crossed my mind, I was planning on moving the pressure transducer to closer to the pump to see what the best output is.

Right now it's 3/8" line to a -6 into and out of both fuel filter and regulator, so 4 total fittings between the pump and the rail. I am measuring fuel pressure at the regulator so that would be between fittings 3&4 if 1 was closest to the pump.

Wouldn't take much to change to a -8 feed line if need be.

[dually681]

bypass the filter altogether. put a straight hose and see if that helps. if not the restriction is somewhere else.

[zbls2121]

I did change the filter to a nice unit, no improvement was seen from that. Two different styles of filters, both decent quality the 2nd larger than its predecessor.

I went ahead and dropped the fuel tank again to make sure there were no obstructions in the fuel system. Found the weather pack seal in the fuel pump connector had swollen up to twice its original size and started to deteriorate. That doesn't make me feel too good about the quality of the pump. I am only running pump gas (E10 really) so that should not have happened. I also found the metal fuel pump check valve retainer had come off the pump and was stuck in the rubber line between the pump and the steel tube out of the tank. Not enough to cause and issue but again quality concern.

Since the tank was down I went ahead and bumped everything up to a -8AN, reassembled and test drove, same pressure drop. Next step is either a larger pump or a pump voltage booster.

I still feel I am running this pump too close to its limits with my pressure, Lambda and likely very high BSFC from lack of timing. Hell, maybe the pump is just junk.

[thirdgen60]

I have an LSA blower on a 6.0L and one thing I noticed was i always had a lean spike when i would tip in the throttle. It ended up being Injector timing related. Started playing with the the Injection Timing Boundary, Normal Injection Target vs. ECT, and Makeup Injection Target vs. ECT based on a suggestion from another member and it seemed to help a lot. it make sense because the injector are further up in the port compared to any other ls intake so the amount of time between when the injector fires and the fuel reaches the cylinder is different.

[Frost]

Any chance that's a flea-bay knock-off pump? I've made 700-740rwhp (manual trans though) a dozen plus times with the Stealth 340 and referenced FMFPR.

[zbls2121]

I have an LSA blower on a 6.0L and one thing I noticed was i always had a lean spike when i would tip in the throttle. It ended up being Injector timing related. Started playing with the the Injection Timing Boundary, Normal Injection Target vs. ECT, and Makeup Injection Target vs. ECT based on a suggestion from another member and it seemed to help a lot. it make sense because the injector are further up in the port compared to any other ls intake so the amount of time between when the injector fires and the fuel reaches the cylinder is different.

That is something I wanted to mess with but haven't since I have been having fuel system issues, do you mind disclosing what value worked best for your setup?

Any chance that's a flea-bay knock-off pump? I've made 700-740rwhp (manual trans though) a dozen plus times with the Stealth 340 and referenced FMFPR.

Got it straight from Summit. I am thinking that the pump is just junk. The connector seal swelled up while using pump gas, the pump check valve retainer came off, and even with the boost a pump I am still not able to hold consistent pressure up in the 9.5-10psi range. Though it has improved dramatically vs without it.

I did have a 2VDC voltage drop during the initial install, probably only ran it that way for a day... driving around logging... before I stopped and waited to get a fuel pressure transducer.

Even during the log yesterday with the BAP running, the pump just sounded rough. I think perhaps I will pull the return line off the regulator, bump it up to 68psi and jump the pump and dump it into a container and time it.

[Pulse_GTO]

Any updates?

[zbls2121]

Any updates?

The short of the long - No.

Car is up for the winter. I do have an Aeromotive A1000 external fuel pump from another project... and my tank already has a sump for external. However, I think one more try is in order with my old Walbro 255. If that can't hold pressure with a BAP then there is something between the outside surface of the tank and the pump internal that is either a fluid or electrical restriction.

[zbls2121]

Update!

It has been a while. With the car up for winter and another vehicle added to the fleet the slomaro took a back seat.

Short of the long is the new Aeromotive fuel pump was defective. Aeromotive did replace it free of charge as it was covered under warranty.

I made a few pulls with the new pump in and the fuel pressure does not fall off, it does however trend (consistently) down at higher fuel pressures so I think my scaling is a tad off. I have been able to tweak the VE map now that my fuel pressure is stable up high and the map is looking less funky but still needs lots of refinement. It is also more consistent when I change it, the EQ error doesn't seem to elude over and over.

With that being said. I still have a massive lean tip-in at lower throttle higher load points like taking off in first or blipping the throttle quickly.

Any hints or tips? I have experimented with the injection timing boundary and that seem to help a bit during higher loads. Should I sway values more? Stock was 6.5 reference pulses, I tried 6.0 and 7.0. Other areas to investigate?

Thanks all.

[zbls2121]

TTT?

No one else working on an LSA LS1 swap?

[AutoWiz]

Hey. So lets talk about this..



This table is Volumetric Efficiency. The important word for you to pay attention to here is efficiency. Belt driven blowers typically are not very efficient at lower rpm's because the engine has the extra drag without the added power. And no matter the case engines do not hold the same level of efficiency across the rpm range or across the load range. Ve maps should not be flat or have flat spots in them. The ve table should resemble an open parachute with no large changes from one cell to the next and its peak(the motors peak efficiency) being just before max hp as revealed by dyno pulls. And the really big question I have is why for the love of god are you on a 3 bar os with an lsa blower? You aren't going to get 3 bar out of that blower. That's a pipedream. So then why are you riding around with only 1/3 of your ve table for the areas your engine spends most of its time?? I mean what is the most kpa you have logged? 160? You will never see 200kpa with your setup> You should have a 2 bar map and os. This will give you breakpoints every 10kpa instead of every 15kpa.

[AutoWiz]

Here is an example of a 2 bar ve table for a pd blown ls6 that I setup with the same screws(eaton tvs) but in a magnuson blower..



And that ve table goes to this 1969 GTO with a magnuson tvs2300 sitting atop a ls6 with dart pro1 ls2 heads..



I have detailed build threads on this car here:
https://www.superchargerforums.com/t...ring-gto.3135/
And here:
http://www.digitalcorvettes.com/foru...d.php?t=241858
Dyno video is here:
https://www.youtube.com/watch?v=l7008Ydrv3Q