Left Hand turn fuel starvation on WOT

[xwd]

Lots of STi guys who do a lot of tracking end up using surge tanks. I used one of these in my 02 WRX so I could run almost no gas in the tank. You would be surprised what a small tank like that can do even for long sweepers.

http://www.hyperflow.com.au/index.ph...d=hyast-wrx001

Long sweepers do cause more issues. I think Phil @ Element Tuning (who seems to have disappeared) was getting minor fuel starvation last year even in a stock car when he first started running his car with big slicks.

[Sportsguy83]

Originally Posted by King Tut

No thanks on a higher mounted aftermarket fuel cell. I would rather see a new fuel pump bucket solution. I know you guys are not the only two out there running 10/10ths on track. Has anyone else had this issue?

Originally Posted by Huehuecoyotl

its going to be in stock location...rip out old tanks, put in new
by now you know, I go to try and test out whomever's solutions I like* and I think I am liking this alot

See below:

Originally Posted by Dustin@Dynosty

And just FYI, we are finishing up the last little pieces to our fuel system that will allow you to drop this monster in the tank and not have to worry about double o-rings or running out of fuel

http://www.ft86club.com/forums/showp...1&postcount=17

And some posts down:

Originally Posted by Dustin@Dynosty

If the machine shop stays on target, we will have the production version pieces in middle of next week and we will do a final test to verify nothing changed from the prototypes and then we will release to the public. This will be full feed and return lines with rails, regulator and fuel lines for those really looking to push the limits with out having to run an additional external tank.

[Huehuecoyotl]

for me its long sweeper on throttle-->[brake]greater than 110 degree left[accel]-----> straightway that seems to be a good test model

I considered a surge tank but its really a band aid, and becomes a smaller and smaller bandaid as you make more and more power and add more and more G's, if you dont fix the problem with the main tanks, the surge is kinda temporary fix and yes, I agree 100% it could well be the solution to- this all needs to be tested

I dont think this is the same tank in this car as in STI

[Dave-ROR]

Originally Posted by FRSPirate

Yeah, heard about the fuel cell foam in bikes as well.
Quick search has a lot of people raving about this stuff:
http://www.fuelsafe.com/store/foam-baffling.html
I have read that you may need to replace it more frequently and that you may need to run another filter but it may be related to cheaper foam. Everything else i have read, the guys linked above are still the first choice in foam baffling. Most complaints are about the cheap stuff from Jegs and Summit.

I would suspect all foam will deteriorate eventually. We've had it happen in fuel cells using good foam, but it took several years to do so.

[xwd]

Originally Posted by Huehuecoyotl

for me its long sweeper on throttle-->[brake]greater than 110 degree left[accel]-----> straightway that seems to be a good test model

I considered a surge tank but its really a band aid, and becomes a smaller and smaller bandaid as you make more and more power and add more and more G's, if you dont fix the problem with the main tanks, the surge is kinda temporary fix and yes, I agree 100% it could well be the solution to- this all needs to be tested

I dont think this is the same tank in this car as in STI

I'm sure it's not the same tank. I've seen guys in WRX/STi's use them in cars pushing 600WHP and other cars even more. That's using a setup with say dual Bosch 044 pumps. It's a solution if you don't feel like using an actual fuel cell.

Foam deteriorates, I wouldn't use it in anything but an actual fuel cell which you can take it out easily. And don't use it with E85. I've heard of guys using wiffle balls with success. Not sure you could put those in the tank though.

[chadstyle]

@Huehuecoyotl I appreciate your in depth testing on not only this issue but many others ranging from pentosin to Vortech. I know my question is off topic so I apologize..you mention that you're not satisfied until you have it running like a fine tuned watch on the track. I grew up racing dirt bikes and shifter karts so I can appreciate that but in my old age, dyno tuning for 93 and E85 is about as far as I go. So my question lies within your lap times. I'm sure you frequent a local track and I know you started tracking the car when it was almost new. Where were your lap times then and where are they now after FI, suspension, etc? Just curious to see the improvement in time on a track in comparison to the mods you have completed. If you have another thread discussing that already, link me up.

Thanks again,

Chad

[Huehuecoyotl]

Originally Posted by chadstyle

@Huehuecoyotl I appreciate your in depth testing on not only this issue but many others ranging from pentosin to Vortech. I know my question is off topic so I apologize..you mention that you're not satisfied until you have it running like a fine tuned watch on the track. I grew up racing dirt bikes and shifter karts so I can appreciate that but in my old age, dyno tuning for 93 and E85 is about as far as I go. So my question lies within your lap times. I'm sure you frequent a local track and I know you started tracking the car when it was almost new. Where were your lap times then and where are they now after FI, suspension, etc? Just curious to see the improvement in time on a track in comparison to the mods you have completed. If you have another thread discussing that already, link me up.

Thanks again,

Chad

Youre very welcome, I do the testing for myself, but know its a community service too.

Even tuning for 93 or e85, what we do to say we're done on a dyno and what we learn on the track after many logs allows my tuner to build a file for me(and likely you and other customers) thats made using real world data, in a far from ideal set of conditions vs a dyno room.

Up till this point it has run like a watch, so I didnt have this issue with the my lower power levels, so each time I go up in power I try to track in between, for my own benefit,again.

As I dont have the baselines you want on hand, what we will do is take my wifes car which is a bone stock BRZ with a TRD drop in, vs mine 'well built' on a day I'm renting a transponder(I dont when I am just tuning,testing and logging) I want to share that data too!

[robispec]

Originally Posted by CSG Mike

I believe the issue is from their respective cars having higher rates of consumption (boost in one case, E85 in the other).

I'm honestly surprised that a stockish car has starvation issues. We ran at ACS with no issue, even with the gas light on (14 degree banked turn, sustained for over 10 seconds, nearly 2G lateral)

@ acs I starve in the rock garden before the straight
@ brp 13 ccw coming off the riverside into the bus stop
@ chuckwalla going through the huge lefthander (3-4 i think).

all big FLAT lefthanders no issues in the banking at all.

All can be managed by a short shift to 6th but the power is not there...then

[CSG Mike]

Originally Posted by robispec

@ acs I starve in the rock garden before the straight
@ brp 13 ccw coming off the riverside into the bus stop
@ chuckwalla going through the huge lefthander (3-4 i think).

all big FLAT lefthanders no issues in the banking at all.

All can be managed by a short shift to 6th but the power is not there...then

We should see if the aftermarket pump still has the issue when you're running a 91/100 octane map... or have you already done this?

[Huehuecoyotl]

its the piping flo and return rates not the pump itself
I too am consistent @ FIR West before the straight when doing CCW and @ amp after the 180turn CW-both Flat as a pancake

My bet is a pump wont cure this...I will be game to see what Dynosty is up to but they been making power, not sure if they have the same G force induced stuff we're seeing in only the flat in same conditions of use, different pumps, different tunes, different fuels, this isnt a fuel supply issue thats pump limited, its limited by return rate I think

[robispec]

Originally Posted by CSG Mike

We should see if the aftermarket pump still has the issue when you're running a 91/100 octane map... or have you already done this?

don't run 91 at the track...lol

e85 ftw lol

but will need to at chuckwalla... or have a 2 second margin! car only makes about 12 more WHP but the temps are all cooler!

[CSG Mike]

Don't have the budget to run 100

[orthojoe]

Originally Posted by jack43

That reminds me why I changed my mind about wanting a Cayman: too many reports of engines blowing up in left turns. Search '987.1 oiling issues'.

Most are on the track w/ sticky tires but some are off-ramps etc on the street.

Those oiling issues were fixed with the 9A1 DFI engines. Yes, it was a problem if you were running serious rubber. The 987.2s do not have oiling issues. I have datalogs to prove it.

Originally Posted by Huehuecoyotl

those of you who have no clue what this is, go spend a bunch of time on the track and you will see this thing rear its ugly head, its systemic, not build specific
this will be something that anyone and everyone who tracks, as your skills and build increase, you will all need.

What makes you say this? While it is a design flaw in the fuel system, I think the reason you are running into problems is a) increased fuel consumption rate due to the supercharger you are running, and b) R comps pulling much higher Gs. These problems can also be track specific. Some track configurations cause problems, and some dont

[Huehuecoyotl]

Originally Posted by orthojoe

What makes you say this? While it is a design flaw in the fuel system, I think the reason you are running into problems is a) increased fuel consumption rate due to the supercharger you are running, and b) R comps pulling much higher Gs. These problems can also be track specific. Some track configurations cause problems, and some dont

Youre absolutely correct, I thought it but didnt write it , I meant anyone going for higher flo rates or FI plus track will see this- Robispec gets this with his NA e85 setup with aftermarket pump, so its nothing to do with Vortech, and anyone who draws extended fuel demand on the oe plumbing will see this ON THE TRACK, vortech pulls fuel thru the entire band, but I would bet a million bucks other FI cars, and other high fuel demand tuned NA cars, like Robi;'s will see this. I know Perrin has reports from one of his clients too, same thing, so its not just my build. Sorry for the mistyped thought, will go fix it