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tfrasca's 142 Turbo Project

Wait, just checked out the fuel pump install post, you have a filter before the pump! You can't do that. At least, not with a small one like that. EFI pumps are NOT designed to pull vacuum, and that means be fed by a fine filter or long run or uphill run. They are designed to push pressure, take a little soft junk, and force it INTO a filter. On my ute I have a massive marine filter with housing that I suck fuel through with a carter black vane pump and had trouble with even that sucking the hose down due to the restriction of this huge thing. That feeds my surge tank and the 044 pulls and feeds the rail from the surge tank with no up stream filter (though there should be one). You need to migrate that filter into the supply line post pump, not pre pump in between pump and tank. Having said all that, your reg still sounds to blame.

On the tank side you need something low restriction like a gauze or sock, only. Or something massive like the marine one I have + something that CAN draw a vacuum.
 
You basically can't get steady fuel pressure with different air pressures/vacuums even if the pump is pathetic. So it sure sounds like reg.

You can test this at idle with a syringe and the regulator hose, you can pull vacuum on it and reduce pressure and you can push boost into it and create pressure, if you don't get any change from those at idle when the engine is using NONE and you can still drive it into boost, then it's the reg for sure. Are you sure the hose isn't kinked/collapsed? hose not designed for vacuum can block itself by collapsing and be slow to reopen. On my KP60 there is a vac port that is completely blocked, no signal at all. I tried forcing it with compressed air, but it's like there's glue or a screw in the way :-D So I went back to the dizzy.

I'm waiting on the Mity-vac I had to order from Amazon because no local shop had the one that could make boost and vacuum. But, my regulator does react to vacuum. The rubber (not silicone) vacuum line is not clogged, and plugging it into the regulator makes the fuel pressure drop about 5-6 psi at idle.

Wait, just checked out the fuel pump install post, you have a filter before the pump! You can't do that. At least, not with a small one like that. EFI pumps are NOT designed to pull vacuum, and that means be fed by a fine filter or long run or uphill run. They are designed to push pressure, take a little soft junk, and force it INTO a filter. On my ute I have a massive marine filter with housing that I suck fuel through with a carter black vane pump and had trouble with even that sucking the hose down due to the restriction of this huge thing. That feeds my surge tank and the 044 pulls and feeds the rail from the surge tank with no up stream filter (though there should be one). You need to migrate that filter into the supply line post pump, not pre pump in between pump and tank. Having said all that, your reg still sounds to blame.

On the tank side you need something low restriction like a gauze or sock, only. Or something massive like the marine one I have + something that CAN draw a vacuum.

I actually got rid of that pre pump filter shortly after I got the car running. The pump has no restriction before it, but also no filtration. I supposed that could have caused a problem with that pump, too. I'll test the regulator and go from there.
 
If you're shooting for 300 whp you should just use lh imo is not a very hard goal especially with a stick shift car

How many people are making that on LH? I know it's been done (I think Gary is, actually?), but it seems like you're taking it to its limit at that point. Seems like going MS allows for more headroom, no?

I'm open to suggestions.
 
I'm having issues due to the crappy fuel we get here, but honestly, if I did a legit TUNE in my car, it would be solid on 2.4, without the need for E85. My biggest issues have been knock enrichment but that's due to the spark tune being too hot. I also have idle issues related to cam timing and LH not being able to respond quickly enough on throttle close, and going rich pretty late in the game when rolling into boost. A change in the fuel map there might be efficient, not sure though being MAF based.
 
I'm waiting on the Mity-vac I had to order from Amazon because no local shop had the one that could make boost and vacuum. But, my regulator does react to vacuum. The rubber (not silicone) vacuum line is not clogged, and plugging it into the regulator makes the fuel pressure drop about 5-6 psi at idle.
I would have thought you could buy a large needle-less syringe from a "drug store" locally pretty easily? No?


I actually got rid of that pre pump filter shortly after I got the car running. The pump has no restriction before it, but also no filtration. I supposed that could have caused a problem with that pump, too. I'll test the regulator and go from there.
Good. I doubt it unless your tank was dirty or your pumped gas is, or you're careless filling it (I doubt that, given what I've seen here!). The only other critique I had of that setup was the sharp/straight inlet, an upside down mushroom will be much less likely to create whirl pools under suction, much like the oil pump pickup in these engines. But I doubt this is your issue, either.
 
I did it on lh 2.4 for a long time with no issues. I never had any problems with it other then one failed fuel pump relay. Never any issues with knock enrichment and it got good mileage. I will say this if you are going Ms , step up and get a Ms 3x or something that can do full sequential. It makes life a whole lot easier.

I say fix your fuel system, throw a more efficient turbo on it and do supporting mods, like injectors and maf and see how you like it. My lh car was so reliable and predictable.
 
Got a mity-vac, tested the FPR. First thing I noticed is that it has a *slight* boost leak, but nothing that would prevent it from raising fuel pressure. If I pump it up to 15 psi, it loses about 1 psi every few seconds. If I keep pressurizing it, like the turbo would, it can maintain boost and fuel pressure.

Even with the leak, fuel pressure goes up linearly with boost. I'll order a rebuild kit for this FPR, unless anyone has a better suggestion for a nice adjustable FPR. I've had issues with this one, obviously.

Aside from that, I feel like I've narrowed it down to a pump capacity/setup issue. Let's say I add a lift pump and surge tank to the system. Is there a high flowing lift pump that I can mount externally and use the same pickup that I'm currently using for my high pressure pump? I know that must be done all the time, but everything I can find puts the lift/feed pump inside the tank. If I could hook up a lift pump to my current tank pickup, then plumb that to a Bosch 044 inside a small surge tank, it would allow me not to cut into my tank again and fit everything under the car. Suggestions?
 
External mounted, just above the tank right off the pickup tube, but the rated scavenge length is like 4 feet uphill, so I think it’s fine. I have no issues at all, and when it does suck air it’s whir changes, so it’s like having a low fuel buzzer, and I’ve got a 2liter surge tank that stays completely full.
 
External mounted, just above the tank right off the pickup tube, but the rated scavenge length is like 4 feet uphill, so I think it?s fine. I have no issues at all, and when it does suck air it?s whir changes, so it?s like having a low fuel buzzer, and I?ve got a 2liter surge tank that stays completely full.

Excellent. Do you happen to have a link or info on the lift pump?
 
A lift pump doesn't have to be inside the tank, nor does the high pressure pump need to be inside the surge tank.

The lift pump only has to supply the average fuel requirements of your use unless the surge tank is too small to buffer that use. Gear to gear, in a quick car, the lift pump can be 3/4 the flow of the main pump, or there abouts. Salt flats cars need matching pumps.

This is what I have for a lift pump in my truck pushing about 400hp crank: https://www.summitracing.com/int/parts/crt-p4601hp

The lift pump doesn't need to supply much/any pressure, it's only pushing volume - carby pumps are good for this, max pressure of 7psi or whatever, and flow of "big block with the works" :-)

The carters are vane pumps, a lot like power steering pumps are, they can move volume and draw vacuum just fine.

Cummins diesel lift pump insides:

CumminsLiftPumpLidOff.jpg






Picture I drew a decade ago:

correct-surgetank-fuel-system.png






My old setup when I used a Bosch 910 as a lift pump, this was a waste of a good pump, really - in the end it just died in storage, oh well:

100_4161.jpeg
 
A lift pump doesn't have to be inside the tank, nor does the high pressure pump need to be inside the surge tank....

That's what I needed to know, about the lift pump. It's also good to see some examples, thanks.

I want the main pump inside the surge tank for packaging and noise. This is the surge tank that I would like to use, because it's only about 8x4".

https://store.034motorsport.com/fully-enclosed-fp34-fuel-pump-surge-tank-for-bosch-044-motorsport-fuel-pump.html

There's a chance I could mount that between the tank and the spare tire well, where my current Bosch pump is. Either that or up above the axle by my fuel filter.
 
Yeah, my setup uses both external pumps. And even with two feet of line to and from the tank to each pump there’s no issues with pressure keeping up or pump starvation.
 
Fair enough re noise, fuel pumps are pretty loud if the car is a daily/street car. Even with the stock Volvo jello mounting you can still hear them way behind you.

That surge tank... hmmm, I kinda like the design, however I do not like the size. Have you ever seen how quickly an 044 could push a litre out? Damn quick. I'd want the lift pump to exceed the main pump with that little volume (it's not 1l it's 1l minus pump and all fittings...). Even then, when the tank gets low you could be running the main pump dry before the fuel comes back to the lift pump pickup.

IE, shape and volume are key design tenets of a surge tank. Tall FTW. The one in my picture above doesn't satisfy me, I'll be designing my own at some later date to replace it, and it'll be taller and narrower with a tapered lower section for final pickup and flat baffles for anti slosh near the bitter end. Moral of the story, even with a surge tank, don't run your turbo car out of gas! :-D
 
But at full tilt, how many liters of fuel is actually being used at the injectors? That’s a better way to size the lift pump. Finding a pump that can out flow you 044 that also has the ability to scavenge and possibly be run dry is not going to be easy.
 
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