1990 Eclipse GSX

[We're on Boost]

I don't use a variable speed controller. That's one of the reasons why I go with Fuelab pump. Their pumps have a simple builtin speed controller. So you won't need one externally if what you would need is simply switching between the max speed and the reduced speed (not variable speed control). Like I use the reduced speed for idling and streets by grounding one terminal on the pump, and switch to the max speed only before pulling hard in highway or before the line in the track. In this case, it doesn't require to buy an additional speed controller like the common large aftermarket fuel pumps that run only in max speed and require a speed controller for streets or long time idling.

That looks really good. I see they give separate flow and current curves for the reduced speed mode so you can know what to expect from that. And in the install instructions I see how the switching back and forth between modes can be with a simple switch on the dashboard (example 3), or can be automatic by a pressure switch (example 4). I like it!

 

[DSMPT]

Took the 1g out for a spin to test the new fuel pump. Just with low boost somewhere around 26~27 psi with only 91 gas. It seems I got back the proper fuel pressure now. When the old pump started to fail, it couldn't build the proper fuel pressure around that range, it stopped building the fuel pressure when exceeding 22~23 psi. It didn't happen today

 

[We're on Boost]

Took the 1g for a spin to test the new fuel pump. Just with low boost somewhere around 26~27 psi with only 91 gas. It seems I got back the proper fuel pressure now. When the old pump started to fail, it couldn't build the proper fuel pressure around that range, it stopped building the fuel pressure when exceeding 22~23 psi. It didn't happen today

That's awesome.

I looked back a ways to see if I've already asked you this question - looks like not. So here it is.
With the fuel pump external only, and no pump in the tank, there is the possibility of having cavitation in the line that runs from the tank outlet to the pump inlet. And there might be times when on a cold start, that line has air in it, so the pump is sucking air for a bit when it first starts up, and I don't know if that might be bad for the pump after a while.

I see the pic in post #71, the pump is mounted several inches higher than the tank outlet. So these things could maybe happen when the level of fuel is very low in the tank. I'd love to have no pumps in the tank at all. It just seems odd to me having large electrical current inside the fuel tank. But the potential for not always having positive feed to the pump inlet is one of the things that has kept me from doing it.

What do you think? Does it work just fine and you can't tell any problem from it? Is it good enough just to have large diameter lines going from the tank to the pump, and starting the pump a few seconds before starting the engine? Oh and having an anti-back-flow valve after the pump probably too?

 

[DSMPT]

That's awesome.

I looked back a ways to see if I've already asked you this question - looks like not. So here it is.
With the fuel pump external only, and no pump in the tank, there is the possibility of having cavitation in the line that runs from the tank outlet to the pump inlet. And there might be times when on a cold start, that line has air in it, so the pump is sucking air for a bit when it first starts up, and I don't know if that might be bad for the pump after a while.

I see the pic in post #71, the pump is mounted several inches higher than the tank outlet. So these things could maybe happen when the level of fuel is very low in the tank. I'd love to have no pumps in the tank at all. It just seems odd to me having large electrical current inside the fuel tank. But the potential for not always having positive feed to the pump inlet is one of the things that has kept me from doing it.

What do you think? Does it work just fine and you can't tell any problem from it? Is it good enough just to have large diameter lines going from the tank to the pump, and starting the pump a few seconds before starting the engine? Oh and having an anti-back-flow valve after the pump probably too?

I know what you mean. That's was my concern before going this JMF fuel cell. But the fuel pump mounting bracket is actually from JMF, so most of people mount the fuel pump on there.

For my use, I have no issue at all. I don't even have a check valve in my fuel system, so the fuel pressure immediately gets zero when the engine stops running, but it starts up right away when I crank, even for the first time in 6 months (I have 10AN feed line and 8AN return line). So in ECU I set just 1 second to prime the fuel pump when turn the key on (This is just to hear the pump sound to know if the fuel pump circuit is fine).
I don't know all external pumps but mine is self priming good. The only moment I had cavitation was when making turns with very low fuel level. But that's because of the fuel cell sump side, not the pump position.

 

[We're on Boost]

For my use, I have no issue at all. I don't even have a check valve in my fuel system, so the fuel pressure immediately gets zero when the engine stops running, but it starts up right away when I crank, even for the first time in 6 months (I have 10AN feed line and 8AN return line). So in ECU I set just 1 second to prime the fuel pump when turn the key on (This is just to hear the pump sound to know if the fuel pump circuit is fine).
I don't know all external pumps but mine is self priming good. The only moment I had cavitation was when making turns with very low fuel level. But that's because of the fuel cell sump side, not the pump position.

That sounds great, it's what I was hoping for.
I like not even having a check valve. The check valve is more stuff hanging around there under the car that could take damage, so it's great that we don't even need one. 1 second to prime. Yeah! I have my prime after Key On set to 5 seconds for the same reason, just to hear that everything is running before I push the starter button. It takes me a couple seconds to move my hand from the key to the starter button anyway.

Self priming ok I'm not too surprised, but again that's good news. I've been using a little Airtex rollervane type electric pump in my portable fueling rig since 2017 and it always starts out sucking air for the first few seconds. All the fuel I've put into my car for the last 7 years has been put in with that little pump sucking out of 6 gallon outboard motor tanks. The tanks have had either E98, E85, or gasoline in them, the little pump just keeps going.
So to me this sounds pretty good. If I ever needed or wanted to replace my fuel tank for some reason, I think I'd go this way.

 

[DSMPT]

Recently I'm playing with my DSMs more often than usual. I don't know why but I'm motivated somehow.

 

[DSMPT]

Went to make a safe fuel/ignition map without the W/M injection as a base map for trying to use the flex fuel feature with methanol. Actually I was enjoying the 1g's BOV sound after a long time. I felt younger

 

[DSMPT]

Going back with the .81A/R turbine housing for higher boost at high RPM. The .61 and .68 is fun while the boost is below 30 psi on streets. But obviously the flow is insufficient at higher RPM.
It's T4 open, the A/R is, .81, .68, .61 from left. I have a 1.15, too. But it's too big.

 

[92AWDHX40]

So what is the spool time on the previous set up compared to this new one

 

[DSMPT]

So what is the spool time on the previous set up compared to this new one

I compared when the engine was 2.0. Now the engine is 2.15, so there may be a little difference though.
Between the .61/.68 and .81, as for the spool time on my setup, somewhere around 500-800 RPM different. But the turbo is 67mm and the cams are 282/288, who run a 67mm or larger probably run very agressive cams like 280s or up. So anyways the agressive cams wouldn't allow us to see the boost below 5500rpm regardless of the turbine housing A/R.
With the same boost pressure range at high RPM, the exhaust back pressure is really different, with the .81 would make much more power due to less loss by the back pressure. The power difference significantly can be felt.
For example, I now have a 35 psi rate spring in the wastegate, but with the .61 or .68 housing, I need to use boost controller to have 35 psi. Without the boost controller, the gate would start to open at around 25-28 psi. With the .81 housing, I can have 35 psi with no boost controller or with much less duty.
With the .68 housing, I can probably go close to 40 psi by maxing out the boost controller with 2 port connection, but high back pressure would stress out many parts including the turbo and cause much power loss, that's I don't want. Anyways if I want to run 40+ psi of boost again, I definitely need to switch back to the larger A/R housing.