Alright. I think I understand what you're saying about the atmo pressure vs manifold pressure. Not a full understanding in practice, but I understand the general working mechanics of it. I'll definitely do some more reading on the matter to find a solution. I would think a flapper valve with a VERY light spring would work well for that, though I'm not sure.

I actually did find some flanges a while back. They were technically for a Buick 215, but it's the same engine and they would work just the same. A little spendy for just a set of flanges as I recall, but so are turbo systems. I also found some KO3 flanges on summit racing that I can use. I'll actually probably bring them into a v-band and then make a v-band to ko3 adapter. That will also make turbo changes easy in the future if there ends up being an issue with the KO3s.

Thanks again, you've been extremely helpful!

Edit: Found the link to those header flanges.

 

Ok, I checked the RAVE and the factory pump puts out 50 lbs of fuel pressure. The Summit pump I had selected only puts out 45lbs so I'm probably going to use this pump instead which puts out 60 lbs. Oddly enough, the RAVE also says the fuel system has an in line canister style filter. Weird.

I'm also going to yank the extra fuel pump I have in my donor truck and see if I could just bypass the regulator. If I can't then I'll still see if I can re-use the sender and the fuel pickup. The Holley piece I would be using otherwise is kinda expensive.

 

Ok, so I pulled the pump apart and I think I can modify it to work. Here's a picture of the sender. As you can see, there's a spring inside. I think I can either cut the thing open and weld it shut or if that doesn't work then perhaps I can just fill it with JB Weld in both ends or make a plug to go where it was originally placed. Alternatively I can simply plug up the factory fuel line plug and bypass the regulator all together and plumb a new fitting in the top for the fuel line to tie into.

 

Alex I used JB weld on my pump once to seal a crack on the top (on the part that mounts the pressure line). The gas ate it. It took a year but it did work its way through about a half inch of JB weld. I broke down and finally got a new pump. I also used JB weld and a beer can to make a goosneck hitch and it is still good five years later go figure.

 

Thanks for the tip, Charlie. No JB weld for me!

 

you always keep it interesting Alex

 

I sure do try

 

YES! I think I found the final physical piece to the puzzle. It's called a check valve. I'll put one in line between the vacuum line on the intake and the fuel regulator. That way the regulator will not be able to pick up vacuum pressure but it will pick up boost pressure.

Now, the factory regulator says 3.5 bar on the side which translates to 50.75 psi in freedom units. This is backed up by the RAVE manual, so that's what I'll set the aftermarket regulator to. Then, using the vacuum line containing the check valve, the regulator will increase fuel pressure one PSI per PSI of boost allowing the vehicle to not lean out but also not run rich at idle (in theory, though I will set it a little rich to begin with and then tune it to my liking from there using the wideband O2 sensor data.

I've also added a boost gauge to my list as well as an in line fuel pressure gauge to help with dialing in the regulator which will thread directly into the aftermarket regulator then slip right into the factory fuel line using this fitting with this fitting on the end.

I'll also use fittings like these for the fuel return directly to the tank as well as from the factory fuel pump to the fuel regulator which will be mounted on the frame close to where my fuel filter currently is. I will also be leaving the fuel filter in line.

 

Ok, I know I said I was done with the fuel system before, but now I mean it for real. I'm adding a .025 orifice post-check valve so that once the valve closes when not on boost then the regulator can return to atmospheric pressure. This one required a lot of adapters to fit. We started with this t-coupling in the line between the check valve and the regulator, with this adapter, attached with this male to male coupler, followed by this... sprayer nozzle. Yep. That's all I could find that will (probably) thread in. I'll be using lots of teflon tape it would seem.

 

Ok, given further research it appears the KO3s are going to be too small. I think I'm going to hold out for a set of T28s which means this project is going to get put on hold for a while. Looking at getting a new used car to daily drive instead of the Disco and that's going to eat pretty much all of my disposable income. A factory '72 Chevelle SS396. I really love spending money on gas, evidentally.

Anyway, if anyone else gas the ***** and the bank account to attempt this in the mean time, I'll help any way I can. Most of the research has been done, probably cost about 3k said and done if you do all the work yourself. Some of the fittings and hoses I've posted won't fit a turbo style other than the ko3, but thats just a matter of finding the right sizes. Post or PM any questions and I'll try to get back to this one, probably in 2-3 years.