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NASA PT/TT thread

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Old 06-23-2014, 11:49 AM
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Pretty much anything since I'm on a dyno reclass.
Old 06-24-2014, 03:07 PM
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Were you below a third of a tank? As you probably know fuel slosh in your tank will lead to fuel starvation in extended high G turns. Often this will manifest itself on the straight AFTER the turn as it can take a while for the air bubble to travel down your fuel line.
Old 06-24-2014, 03:11 PM
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If you want to be done with it, put in a surge tank if you can...nothing else I tried worked reliably. With the surge I am good down to fumes basically
Old 06-24-2014, 03:25 PM
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Originally Posted by MagnusRacing
Were you below a third of a tank? As you probably know fuel slosh in your tank will lead to fuel starvation in extended high G turns. Often this will manifest itself on the straight AFTER the turn as it can take a while for the air bubble to travel down your fuel line.
Spot on. Straight going uphill from 2nd gear to 4th, followed by a double apex left turn, ending on a long straight - It manifested right after the turn.

I replaced the fuel assembly a month ago.. the syphon hose looked weak as if it could kink easily but I didn't have time left to order a new one and replace it.

It is happening above 3/4 of a tank. I fill the tank up and run one 20 minute session fine; it will stutter on the second session.
Old 06-24-2014, 03:28 PM
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Originally Posted by dannobre
If you want to be done with it, put in a surge tank if you can...nothing else I tried worked reliably. With the surge I am good down to fumes basically
Sounds interesting. I wouldn't know where to start, though. My first reaction is to just replace the syphon hose (I need at least 3/4 of a tank to meet minimum weight); I was also thinking on going to a S2 assembly.

Next event is the NASA Eastern Championship in Road Atlanta in late August. I have time to figure it out.
Old 06-24-2014, 08:26 PM
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The only place I have seen fuel starvation issues at Road Atlanta is coming out of T5 which is after the esses.
Old 06-25-2014, 06:51 AM
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A 0.5 gal surge tank works wonders in our Chump E30. We've been on track with no starvation and under 2qts in the main tank. Only costs about $100 and an afternoon for a complete setup. I would recommend adding mounts (we use hose clamp around cylindrical tank) in addition to the welded aluminum tabs on the plate. Aluminum fatigues easily and is weak when welded without a post weld heat treat.
Old 06-26-2014, 06:10 AM
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I've gotten fuel starvation twice at RA
Both times on the back straight with just over 1/4 tank
Good spot for it considering you can pit pretty quickly
Old 06-26-2014, 12:01 PM
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If the level is accurate and it happens above 3/4 tank then I'd bet that theres a different issue. I also don't see how the siphon hose will kink if the pump is positioned properly.
Old 06-26-2014, 12:05 PM
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Originally Posted by TeamRX8
If the level is accurate and it happens above 3/4 tank then I'd bet that theres a different issue. I also don't see how the siphon hose will kink if the pump is positioned properly.
The siphon hose looked weak/soft. I will have to take it apart in order to give you more details. My guess is that there is no gas moving from the right side to the left whatsoever.
Old 06-26-2014, 12:13 PM
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If theres 3/4 tank it doesn't seem like it should matter. Even if the siphon saddle was full there'd be over half saddle depth on the pump side. I can't see the pump sucking air under a sustained LH turn at that tank level.
Old 06-26-2014, 02:03 PM
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I agree...you have fuel pump issues if you are having problems that early...
Old 06-26-2014, 02:12 PM
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Fuel pump assembly was replaced a month ago (factory). It could still be the pump! I don't know. Any ideas are welcome.

Here's a video - stuttering happening at 1:23
Old 07-19-2014, 05:19 PM
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More on fuel delivery issue: Please check this thread and let me know your opinion. Thanks!!
https://www.rx8club.com/series-i-tro...l-line-254071/
Old 07-19-2014, 08:39 PM
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The mother's guys install an extra "cross over" pump to move fuel from on side of the tank to another.
Old 07-19-2014, 11:07 PM
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The pump is running without load in that condition, not the same thing as on a running engine

That also means it won't be bypassing, which then also won't siphon fuel from the other side

If you're running it by grounding the check connector per the fuel pump test it's also only running in the low speed mode
Old 08-25-2014, 09:45 AM
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NASA Nationals East

I'll be headed to this event at Road Atlanta (with my MR2 though) - anyone in the general area is welcome to come check it out, $40 ticket for the weekend or $20 for Sunday only being the only downside over a normal regular ol' race weekend but still much cheaper than a pro level race with just as good competition if not moreso in some classes. Should be lots of good racing to watch!

Schedule and such availible at the link below:
NASA Championships Presented by Toyo Tires ? East

I'll be in Group E, running PTF class, car #6. Race on Fri, Race on Sat, Main Event Race on Sunday.

Heberto will be there with his S1 RX8 in Group I running TTC, car #145. Time Trials is best time you are able to run during the event, usually see a few tenths cover all of the podium spots...
Old 08-25-2014, 10:27 AM
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Have fun and good luck!
Old 08-25-2014, 12:10 PM
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I look forward to meeting up with many of you. Bring your spare parts along just in case... I might need them! ;-)

TTC #145
Old 08-25-2014, 04:25 PM
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for those not in the area, web coverage here:
NASA Nationals East
Old 08-25-2014, 07:43 PM
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Originally Posted by kbrewmr2
for those not in the area, web coverage here:
NASA Nationals East
I'll stop by and see you guys. Talked to a Spec Miata guy Saturday that was running at RA with Chin, he 's from Texas and came in early to get some practice in. He was running 1:46's.

Good luck y'all!
Old 09-01-2014, 01:56 PM
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Finally... back home from Road Atlanta. My 1:42s was no match to 1:39s from S2000... That said, it was a lot of fun! Tough track to tackle over one weekend.

The overall NASA Championship experience was the best part. Mazda was also very supportive and organized a nice dinner for all Mazda racers.

Now back to work on the driver mod!
Old 09-01-2014, 05:56 PM
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etzilon: 1:42's are hauling it in an RX-8 around that track. You should be proud of your time. Sorry I didn't make it over to see you. You learned the track well in such a short period of time.

kbrewmr2: understand you got the shaft after taking the championship. That's a real bummer. Sorry to hear that Ken.

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Old 09-01-2014, 07:40 PM
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Thanks, Silver. Data says a 1:39 is possible; I just need consistency.

FWIW, I tried a DTC60 combo all around on Sunday and I did NOT like it as the rear tires are stressed too much and went off rather quickly (wiggly going down T11 was not fun). I am going to try DTC70 in the front and keep DTC60s in the rear.
Old 09-01-2014, 07:49 PM
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I have had that same thing happen with DTC60's all around. Kind of unsettling. Makes riders freak! Never lost it but I do agree on different fronts.

Where did the data tell you that you were loosing time? Do you have a video?


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