My '90 325is LS3 Swap Build Thread

[CLM21]

Yeah I was either gonna get one from GM performance or another company who makes standalone harnesses for swaps. I'm not worried about wiring the engine harness, that's easy enough. I wanna make all the stock gauges work as well, although I'm not gonna have ac. I'm just worried about that mostly as well as the ignition wiring. And yeah the temp sensor and oil sensor were my biggest questions. I may copy what you did. Speedo is easy enough because that's just in the diff... Haven't really looked into the tach at all yet.

[ultimateracing335i]

Do you have a gm performance harness? It seems straight forward. I'm building a street car, so I'm trying to get all the guages and ac to work. The gm performance harness has a fan output as well as a fuel pump output, so all you need is ignition and you can start it. I built a bracket for the drive by wire pedal, made an intake with a maf bung, modified the bmw temp sensor to fit the caped ls port in the head and made a bung for the bmw oil pressure sensor that screws into the existing valley pan.

[CLM21]

Cool, how bad is the wiring? That's the only part that I'm not looking forward too.

[ultimateracing335i]

I'm just wiring in bmw sensors. I can start it any day now.

[CLM21]

Ok, haven't really even thought about the process of mounting that yet. How close are you with your build? Seems like youre getting close to firing up...

[ultimateracing335i]

You will find it tight for the remote filter on the drivers side. I ran it to the passengers side.

[CLM21]

Yeah I saw that too, and no I didn't do it. I wasn't quite sure why they said to do it? They didn't put any reasoning in there.

[ultimateracing335i]

I just looked at the sikky oil pan instructions. It says to trim the baffle. Did you do that?

[CLM21]

I think stock is a return style? Not quite sure... but the stock hardlines run from the fuel tank on the pass side across underneath the body to the drivers side, and then run up along that frame rail. Then turn up into the engine bay right by where the brake proportioning valve is. And then assuming its a return style, the return follows the exact same route because I remember there being 2 fuel lines along the drivers side frame rail.

I'm planning on doing pretty much the same thing, just with all new lines. And Im using earl's pro-lite 350, not using hard lines.

[Q8y_drifter]

I have a late model e30, so just a single in-tank Walbro 255, vette FPR, 3/8in hose for feed and 5/16 for return. I can always go with an aftermarket FPR if the vette one turns out to be bad. Im not sure if i should go with rubber hoses along the frame rail or go with hard lines. Actually I'm not even sure what the stock setup is, i have to take a look under there tomorrow. Also not sure what to do with the tank vent line.

[CLM21]

Well im doing a fuel cell in the trunk. Probably -10AN line out of the cell to the pump mounted right after/below the cell. 10 micron filter in front of the pump, 100 micron after. -8AN line out of the pump into the aeromotive regulator. Then return line from regulator, cant remember the size. I think -8AN maybe -6AN. Then I'll probably run the feed -8AN line along the frame rail under the car near where the stock lines ran up to the fuel rails.

I definitely went wayyyy wayyy too big. Just wanted room to grow and didn't want the fuel system to be a question.

What are your question marks for your fuel system? The vette FPR seems like definitely a good cheap/easy route, but Ive read some stuff about people seeing bad pressure at their rails. And then probably a walbro pump or the bosch 044 would be cheaper/easier than Im doing. You doing in tank?

[Q8y_drifter]

Awesome work. Interested on how you're gonna setup your fuel system. Spent a lot of time reading on it today, altho I might just go with the vette FPR route.

[CLM21]

Got the entire block put together now. Also got some of the fuel system in.... definitely have room to grow with this lol. Should be getting the fuel cell, regulator, filters, and fittings in tomorrow as well.

[CLM21]

Been a pain in the ass trying to figure that out. First I had a 17/17mm VW MC, but it didnt fill the hole in the plate/firewall. So I decided to switch to a 944 turbo MC, because there is supposed to be a 19/19mm unit that fills the hole in the firewall/adapter plate. Its basically the same exact size/shape as the stock MC. But when I got the MC from online, it wound up being a stepped 23/19 MC. So I still plan on finding a 19/19 porsche 944 turbo MC, but can't find the right part number or anywhere to buy it....


Edit: I actually think I just found it after looking for about a week... I had been checking all porsche models up until 1986, and I think it turns out that the 1987 Porsche 944 with non-abs brakes has a 19/19mm MC. So thats what Ill be going with. It actually has 3 outlets, 2 for rear and 1 for front. So Ill just plug one of the rear ones.

[jksmith]

what mastery cylinder you running with the Massive booster delete