fcd help

[hottscennessey]

It does. They do that because one wastegate isnt able to flow enough exhaust air, so it backs up and starts to exit through the exhaust turbine, causing creep. Generally hondas and DSM's dont produce enough exhaust gasses for this to happen so they should be fine with an internal wastegate, and if they do creep all they have to do is port the turbo elbow, or the wastegate opening to flow more air.

I have run a FCD with a wideband to see the results, it leaned my A/f's out horribly and could have cost me my enigne. Luckily i kept an eye on it. See my dyno sheet and I think you'll change your mind about the FCD, notice how lean I get after my WG starts to creep. I'd say if you do run the FCD, use the ol' pin on the stock FPR to raise the stock FP, or buy an AFPR to up the fuel pressure, that way it can safely cut back some fuel.. but either way i wouldnt do it without a wideband, nor would I ever run a FCD on my vehicle again.

 

[Joel W.]

So, if boost creep kills motors, then 2 WGs sounds like a good thing to me.. Might have to do some more research on it....

It makes just as much sense as running 2 BOVs to prevent surge...

 

[hottscennessey]

exactly, it does make sense, and it is the same concept as the two blow off valves. I just had a faulty actuator, but be careful because fuel cut could save you if you had creep.

 

[Joel W.]

Yeah, I still have FC disabled (hks says raised) with FCD so I watch my boost gauge every second under hard pulls, It's only really bad for me in winter(under 30 degF).

So don't be like me kids..There are better solutions. FCD's are evilbad and they all should be destroyed due to the maftpro or tuning.

(until i get my maftpro, then i'll smash it to bits and take pics.)

 

[hottscennessey]

lol

 

[Joel W.]

So it looks like you leaned out at 4000rpm's and your power fell off about 5-6k rpm's depending on what line you look at? I take it anything below 13 is bad at WOT?

 

[hottscennessey]

well, It was lean pre-boost, and it was lean around 4000 rpms to redline like you said, the lean condition didnt necesarily cause the power loss, but since i was on pump gas its a very dangerous condition, where detonation could have resulted. I would say that the Ideal tune would stay around ~12:1 A/f under boost.

 

[siman]

You guys just explained why Turbonetics wastegates SUCK. They have HUGE valve diameters but the overall travel of the valve is MINIMAL, like 1/4". VS. an HKS or Tial style with over 1" of travel, Tial being the LONGEST.

People wonder why Tial is often voted best WG on the market, there is your answer.

-Jonathan

 

[robeats91t]

Heh, not to bring this thread back from the dead, but fun story re the HKS FCD.

With an HKS downpipe, sport exhaust and 200mm SMF intake, I decided to shim my wastegate to 10psi. Awesome power gains for the low low price of $0.50 in washers. However, a few months later, BAM! BHG. Come to find out when I had the car apart, I noticed that a previous owner had installed an FCD.

Now, I'm not saying that the FCD caused a lean condition that ate my 12k-mile-old oem Toyota headgasket, but based on the evidence presented by hottscennessey and the experiences of others, I think we'll all agree there are better solutions than the FCD.