WOW! Finally, it looks like the G sedan has some thing good. I swapped in a Walbro GSS342 (thanks Sharif!!!) tonight. I was already aware that there were some differences on the sedan pump setup (thanks Phunk!). All the little places that usually get modded on the G and Z pump housings aren't there on the Sedan.....what the sedan does have seems to be a substantially better flowing regulator!!!

I had to make the usual trimmings of the pump tabs (and a couple others) to fit the pump in to the housing. When I reassembled it and started the car, the car had a perfect 52 psi fuel pressure at idle! I have onlt let it idel for a few minutes, but I am so excited that I don't have the 80psi problem!!!

 

thats badass man, you are doing things slowly and correct but damn it, i want you to get into some BOOST!!! hehe

 

what 2psi doesn't fill your need for excitement?

 

Nice job. What was wrong before and with what fuel pump.

 

no problems. I had a stock pump in it before. From my understanding, most people end up with really high fuel pressures (up to 80psi) at idle and cruise when they install a walbro, unless you drill out all sorts of stuff the way TN tells you to do. But then, Charles @ CJ-Motorsports "phunk" was explaing that the mods TN has you perform at really not a good idea at all. He was explaining how the TN fuel pump mods lead to major fuel starvation problems when you get to less than a 1/4 tank of gas.

So basically, I didn't want to have to "drill out" this and "drill out" that to make the walbro work. Apparently, I don't have to because of the better regulator on the sedan!

 

did you go to a full return or just a pump? I know Charles did make CNC plugs for the sedan return system so you could run a return, but I think I got the last one for my buddys car. Congrats on the upgrade Happt Boosting!!!!!!


Ryan

 

i haven't gotten his return fuel system yet

 

really don't need it until you boost around 10lbs. Everyone has a different thought on it, Just get a good tune and have fun.

Ryan

 

Qaud, you are correct in that the sedan has a different fuel pump assembly. I had no idea it had a better regulator though?? 52psi at idle is amazing, given that the Walbro is flowing almost twice as much fuel as the stocker.

 

You learn something new every day, thanks for the info-can you elaborate some more on the design differences?

 

Just to clarify (in regards to how TN instructs some to modify their fuel pump assembly), I do not endorse certain modifications to the fuel canister. Without having ever tested it myself, I would SPECULATE to run into fuel pressure surge issues at lower tank levels if you punch holes in the surge can.

As for the seden unit, we have modified these for proper return setups for a few guys. The regulator definatly has a larger outlet, and there is no modifications needed to support a larger walbro pump, the only mods we perform for guys is to allow continued function of the siphon to keep the passenger side of the tank full.

The only down side is that the output is a little smaller on the Seden units. But I dont think I would worry about it much - I just dont know if I would expect to see a Seden unit pushing over 600-650rwhp like some have done with the stock setup.

 

Ill verify then. This is true regarding TN's modification. Anything under 1/4 tank of gas and car starves for fuel at WOT, I figured the holes in the FP assembly would help fuel get in but thats not the case.

 

I've never been one to go boosting around low on gas anyways. Not just on the Z but any car. If I'm going to run at the track I fill the tank with VP 109 unleaded regardless.

 

MIAPLAYA: give me a call sometime, i can describe to you guys some easy modifications you can make that would be an improvement.

I have done full throttle pulls at over 550rwhp with the gas light on during testing no problems. not recommended, but was just testing.

 

phunk,
I'm out of town right now for a wedding but if its cool I'd like to give you a call on Monday to discuss this stuff. Perhaps I can even get the R&D Chief at Turbonetics on the line too. Thanks for the help.

 

i dont go past 1/4 tank anymore. right after completing my turbo install i ran out of gas, while putting the fuel assy back in, the float got caught on one of the lines that is in the tank, so i thought i had a 1/4 tank but i had no gas at all. i redid the assy and got it straightened out, but now i get gas early, just to be sure.

 

wow, i never fill my tank past half way and boost till its fully empty with no problems....

 

....and you should be able to use all of your tank!! No sense is having a 20 gallon tank that is only driveable for 16 gallons!

 

This is because you mantained the swirl pot and surge can functions of the factory pump setup. TN has you remove those in attemp to increase flow - but the flow is already great enough to support over 600rwhp

 

allright, putting in the walbro 255 into my sedan soon.......sounds like all that is needed is to remove oem pump, install the walbro(after cutting the tabs so it'll fit), and that's it? No need to drill or remove any tabs? please correct if im wrong?!