Turbo Help!!! - Page 2

I haven't tried the T-vacuum thing yet. I'm noticing that when the motor goes into boost at WOT, it seems like I have less power than when I have no boost. This almost sounds like I'm running too rich. I notice if I back off the gas, the power is there. I don't know if I'm too lean or too rich at this point. I'm getting confused....

that could be a problem with your pump.. but if your FMU isnt hooked up to that t fitting, then it isnt working properly....you have to get the right source of vacuum on the FMU.

yea youve gotta get the FMU, the BOV, and the wastegate hooked up right if you want your car to run well. if you dont have the outlet in the compressor hooked up to the wastegate its not going to run right. if the BOV and the FMU arnt hooked up to the line going to the stock regulator then the car isnt going to run right. that t fitting is only a few dollars.

Yeah, the main criteria for getting my car was it had to be stick. Mine would chrip the tires in 2nd too, even after I put good tires on. I even snapped an axle racing my friend when I dropped the clutch. And that was before the turbo...

I think a prelude transmission and axles are in my future.

I changed around the vacuum lines and I'm going to see how things go.

I switched the vacuum lines around, things seem to be slightly better. I'm wondering if FMU's are known for failing. It is a used one, and when boost is present at WOT, the motor has very little power. Oh well, at least it's not leaking oil...

hows the transition from no boost to boost? have you put the new fuel pump in yet? if you havent thats why its not running good at WOT. i have never heard of anyone using their stock fuel pump on their turbo car. your stock pump is really only meant to pump about 30 psi....your turbo system needs so much more than that at WOT. i wouldnt worry about that right so much right now..the transition is the big prob.

also, you cant achieve full boost unless the wastegate is working....

The transistion to boost is fine now. I hooked up the lines from the one feeding the regulator like you mentioned and things are good. I'm sure onnce I get the fuel pump (should be any day now), things will be grand at WOT. The wastegate seems to be alright too.

One thing that I'm still confused about is that I seem to be running rich at idle. Not just a little rich, but fairly rich. Is this normal after doing something like this, or is my FMU stuck closed or something?

ummmmmm you may want to redefine what you said on that one light.... cause achieving full boost on a turbo with 300+ hp efficiency would be a bad thing. ^_^

quote:

ORIGINAL: marbro

ummmmmm you may want to redefine what you said on that one light.... cause achieving full boost on a turbo with 300+ hp efficiency would be a bad thing. ^_^

??? The word "Efficiency" in the turbo world is related to thermaldynamics...what are you saying? I think I missed something.

im saying full boost in the sense of the full boost that you want the engine to run on... in this case 7-8 psi..the boost guage should just absolutely slam into the wall at 7 or 8 psi and stay there rock solid. also MBO it is very common for the car to run rich at idle dont worry too much about it as long as the car idles well. the idle on an engine are the hardest blocks in the fuel map to get right. i see even highly tuned cars with thousands of dollars in stand alone engine management and at idle the auto meter is banging left to right back and forth unable to get it just right. even if the a/f is banged all the way over it is not a problem.

Yeah, idle bounces just like you said. Other than that things are fine. I'm expecting the walbro any day now. Is it absolutley required to install it in tank, or can I get by with it in line? I know i'll have to disable the stock one regardless, and that pumping through it will slightly hurt my psi... just wondering if it's possible to aviod dropping the fuel tank...

hey yea that walbro should be an in tank unit. if it is....when you see it youll know that it has to go in the tank. you shouldnt have to drop the tank though. the pump should be sitting right under the back seat. shouldnt be very hard to get at.. damn it sounds like your is starting to run real good. dont get to frustrated with it just think about how much better its running now as opposed to before. it was only like 2 weeks ago it wasnt even running at all. you officially pimped that install im gonna have to give you an A plus on that one. one more thing though that you should keep in the back of your mind is that your stock injectors have a specific duty cycle which you may or may not be overdoing. if that is the case you will need to upgrade your injectors to a set of 330cc rc engineering injectors. but i think the new pump will probably work just fine.

My hanes manual said I had to drop the tank... I notice there is an access plate though under the back seat. I thought that might have been the pump or the fuel sender. Oh well, that'd be great if I didn't have to drop the tank.

I've read in my research that it's probably not a great idea to do much more than 6 psi with a rising rate FMU, since it will put a lot of stress on the injectors. Any ideas as to what injectors could take the fuel pressures of 8 - 10 psi? Are those rc engineering ones a lot stronger?

This whole install has been a great learning expirience. Yeah, like you said lightshow, last week my car really didn't even run. I wasn't sure if I'd ever get things going when I started piecing together my kit back in october, but things are cookin' now. Thanks all the info!

no prob... glad i was able to help you came to the right place. those rc injectors are outstanding the 330 cc injectors will easily handle 10 psi. and then when you want to move up to about 14 - 20 they have the next step up which i think is around 450cc.

Just so you know theres multiple forms of efficiency when involving a turbo, not just thermal dynamics. When I said said 300 hp efficiency my knowledge of that reference was lacking, but that reference talks about the potential horse power of a car when using a certain turbo. I originally thought it referenced the horsepower that the turbo could produce given the proper airflow, not including the actual engine potential.

its cool marbro we knew what you were talking about. what you said was right that turbo would be easily 72 or 73 percent efficient at 300 hp.

quote:

ORIGINAL: lightshow

its cool marbro we knew what you were talking about. what you said was right that turbo would be easily 72 or 73 percent efficient at 300 hp.

I gotcha.

For those who are lost, like I was at first, power potential can be estimated by lbs/min @ x boost pressure, with correct mapping turbos have efficiencies usually around 70% max on older turbos, the x-axis of the map tell the flow numbers, while the y-axis tells the boost preesure in BAR. The graphed area of the map shows the efficiency of the turbo at those two points. The point of mapping is to make sure that the engine will not choke on the air being supplied or burn up, because the turbo is overheating the air and everything else around it. there's more to it, but that's a decent summary.

E.g.

[IMG]http://img.photobucket.com/albums/v336/bthrist/gt30rcompress2.gif[/IMG]

quote:

ORIGINAL: lightshow

its cool marbro we knew what you were talking about. what you said was right that turbo would be easily 72 or 73 percent efficient at 300 hp.

I gotcha.

For those who are lost, like I was at first, power potential can be estimated by lbs/min @ x boost pressure, with correct mapping turbos have efficiencies usually around 70% max on older turbos, the x-axis of the map tell the flow numbers, while the y-axis tells the boost preesure in BAR. The graphed area of the map shows the efficiency of the turbo at those two points. The point of mapping is to make sure that the engine will not choke on the air being supplied or burn up, because the turbo is overheating the air and everything else around it. there's more to it, but that's a decent summary.

E.g.

http://img.photobucket.com/albums/v336/bthrist/gt30rcompress2.gif

Alright, I installed the fuel pump today. I did have to drop the tank (which sucked) since I only had an access panel that went to the fuel sender. Drop the tank and install the walbro. I had to reuse the stock pick-up filter since the walbro one seemed like it didn't extend as far and wouldn't fit with the stock pump bracket. I also used the stock electric plug.

Reasemble everything and the car doesn't start. You can hear the new pump when you turn the key and stuff. No fuel comes out of the fuel pump outlet directly from the tank. I'm thinking that the polarity of the stock wiring and the pump are reversed, something I should have checked when I had the darn thing out in front of me. Any other ideas? I could swear that I hooked all lines, etc. back in place.

yea i think you have something hooked up wrong....drop that tank again...there is an offf chance that you just dont have enough fuel in the tank to support that high flowing pump...but a full tank is much harder to deal with..

mbo there is a good chance that you just dont have enough fuel in the tank....if you SURE that you hooked everything up right and you can hear the pump doing its thing..then fill that tank up some more.

I'm pretty sure I hooked up everything right. the only thing I'm not sure of is the connector to the pump. The stock plug worked with the walbro, so i just plugged it in, not checking the polarity. I'm wondering if maybe the stock plug and the walbro polarity are opposite. I can hear the pump come on, but nothing comes out. There is just under a quarter of a tank of gas in the tank, is that enough?? thanks man...

Okay I could be a moron at this point but whatever, if the polarity was reversed and you removed the gas cap and the pump was working wouldn't it be blowing air into the tank when you took off the line running to it? So in turn you should be able to hear bubbles in the gas tank if that were your issue correct? Just a thought, could be talking out my ARSE but brainstorming never hurt anyone except my brain

I think that makes sense. Unless the pump can't manipulate air, I would think that would be a sure fire way to check without removing the tank again. It sounded like the pump wasn't really making bubble sounds though, just kinda humming and the hum echoing in the tank. hmm...