Dumbest thing I've ever done at the track today @ VIR...

Cobra4B · #1 08-29-2009, 09:14 PM

Spent 2+ hours cursing the car changing what I thought was a bad fuel pump when in fact my father had run the car dry on track. Didn't think to check the fuel cell until after putting the new pump didn't fix the issue. Now I have a spare fuel pump... 1/2 the time was spent running to the parts store and back.

Last time out I filled the cell on Sunday AM and only ran 2 sessions. So I figured the car would have plenty of gas. I put 5 gallons in this AM and ran the car, then my father ran it and we put 5 more in. Then I ran my 2nd session and on his 2nd he came in and said the car cut out on him and then died by the fuel pumps at VIR.

I never even considered the fuel cell could have been dry... fuel pump was makign a bad noiuse (of course becuaes it was sucking air). We hooked up the truck and tow strap and towed it to the pits. Ran to Advanced and got another Holley Blue pump and came back and installed it to no avail. Then we decided to put gas it it... put my other 2 jugs in it and it fired right up... what a waste of time, money, and frustration... but hey now i have a spare fuel pump!

Hopefully better luck tomorrow.

Panoz26 · #2 08-30-2009, 11:48 AM

WOW.... :o)
B - whats the spec's on the fuel pump. I might want to see if you will sell it.

NZGTRA17 · #3 08-30-2009, 05:01 PM

Quote:

Originally Posted by Cobra4B

Hopefully better luck tomorrow.

Brian, how did the lap times compare with the 3.89 gears?

What sustained peak rpm are you now running at in 4th & 5th gears?

Kel.

Cobra4B · #4 08-30-2009, 09:18 PM

Quote:

Originally Posted by Panoz26

WOW.... :o)
B - whats the spec's on the fuel pump. I might want to see if you will sell it.

It's a holley blue, but we're keeping it as a spare.

Quote:

Originally Posted by NZGTRA17

Brian, how did the lap times compare with the 3.89 gears?

What sustained peak rpm are you now running at in 4th & 5th gears?

Kel.

Well I could never get a clear lap, but I was the fastest car on track. There was a white LS2 C6 T1 car that was a great match for me though.

The 3.89 gears were awesome... the car was faster everywere. My best lap time in traffic was 2:11.5 va. a 2:11.3 running TTS (time trials) last time w/ no traffic.

The only downside was oil temp... I hit 270s now vs. 250s before... lots more time over 6000 rpms in some parts of the track. The only part at VIR where it was a real issue was coming out of Hogs Pen onto the front straight. I'd be at the 6500 rpm limiter a smidge before I wanted to shift, but I learned to deal with it and make the shift anyway.

I honestly never looked at my max rpm in 5th gear, but I was never close to maxing out the car on VIRs two main straights.

The car is screaming over 6000 rpms through turn 3 and into the uphill esses I approach the limiter but never hit it. We have our shift light set at 6000 rpms so the periods of the track where it stays on is a glowing reminder that the motor is singing.

Motor never got over 271 oil temp which was nothing for my Corvette... we did have some issues though.

1. We have coolant seeping from the rear of the driver's side head... did't effect performance at all, but we'll have to get that looked at.

2. Differential was leaking... turns out the rear cover weld (the big circular weld) had a pinhole in it at 12 o'clock. I slathered black RTV on it and all was well. We'll have to get that tack welded.

Starter and fuel pump worked great. I'm going to download my traqmate data and analyze it tomorrow.

NZGTRA17 · #5 08-30-2009, 11:14 PM

Quote:

Originally Posted by Cobra4B

It's a holley blue, but we're keeping it as a spare.

1. We have coolant seeping from the rear of the driver's side head... did't effect performance at all, but we'll have to get that looked at.

Good to hear that all went well Brian. Have you re-torqued the heads/manifold since they were fitted? With any luck this may take care of the problem.

Kel.

PanozDuke · #6 08-31-2009, 12:34 AM

Brian,
270 is too hot for a 302. Check oil viscosity and oil pressure. Any time it's over 230 for extended running, you are asking for it to get very expensive on the bottom end. Mine is max at 218, usually less than 210. Don't use heavy weight (20w50, even 10w40), stick to 5w30 or 10w30 and a synthetic will tolerate more temp than conventional oil before it starts to break down. Last issue (Oct 09) of Grassroots Motorsport had some good info on this subject, page 93.

Mike

Cobra4B · #7 08-31-2009, 09:03 AM

How do you keep it that cool? We have the standard oil cooler which looks to be a large unit. With the stock 5.0 the car stayed in the 210s in the cold months, in the warmer months we were seeing 230s. Now that the car run to 6500 rpms vs. 5000 rpms, it's making 360 horse vs. 240ish horse, and it's 90 degrees outside we're seeing higher temps.

The guys at Panoz said to run 20w50 in it... I was previously running 5w40 Amsoil. I'm sure the 20w50 dino oil is contributing to the higher temps. I'm 100% going back to synthetic after getting it up to 271, but I'm unsure of what viscosity to run. I don't want to run too thin and get lower oil pressures. I'm considering going back to the 5w40 or 10w40 amsoil. Thoughts?

Kel... no... we didn't re-torque anything yet... I'll try that first.

panozracing · #8 08-31-2009, 10:48 AM

def. retorque the heads. Mine loosen up. Also, GM makes tablets you can throw into the rad. fluid that works great to seal small minor head leaks.

We run 5w40 Mobil syn. We have consistent 250-265 deg. temps in 90 deg. weather on every engine we have had in the panoz. They were all diff. kinds of windsor based engines. My engine builder is ok with those temps on our current stroker setup.

Cobra4B · #9 08-31-2009, 10:50 AM

Thanks Brian... what kind of RPMs do you guys turn? I was in the low 260s most of the day... just a couple of times in at 271 during the hottest part of the day running my hardest.

panozracing · #10 08-31-2009, 11:05 AM

we shift at around 6500 pushing hard. We have a 7k limiter but there is not enough fuel coming out of our small 390 carb to run high RPMS so the car is slowing after 6500. We try not to run to 270 degrees, I start shifting a little lower when I see those temps and I can manage fast times and keep the temps around 260 degrees. Its hard when in the dead of summer in south florida.

Cobra4B · #11 08-31-2009, 11:09 AM

Is your motors still a 2-bolt main? I'm thinking of putting my 6750 chip in the car for coming out of hog's pen at VIR, but I'm not sure I want to push this stock 302 bottom end that far.

panozracing · #12 08-31-2009, 11:29 AM

No, the DART windsor iron eagle block has a 4-bolt and also uses some of the better design features of a clevland block (like smaller journal diameters to help with bearing failures) as well as other racing upgrades they designed.

http://www.dartheads.com/products/en...le-blocks.html

All the stock ford sportsman blocks were destroyed due to bearing failures and other heat and stress related issues. That is why we switched.

Cobra4B · #13 08-31-2009, 11:34 AM

Awesome... if this blue oval shits the bed I'm putting a Corvette motor in it.

PanozDuke · #14 08-31-2009, 12:03 PM

Brian,
Not doing anything special except Valvoline synthetic 10w30. I used to use 15w50 Mobil 1 in another 302 and had high oil temps (over 240).

Thicker oil actually causes higher temps from friction created from flow resistance. While you need to ensure an adaquate lube film, higher than necessary viscosity actually creates more friction and this is shown by higher temps. High oil temps break down the oil faster in geometric proportion to temp increase. Higher oil temps also cause rotating assembly failures due to metal fatigue and higher rotation resistence at the bearing surfaces and greater frothing. I'm not an engineer, but I did read the Oct Grassroots article- made sense to me and I'm seeing the lower temps. When I hit 218, ambient was 103 (Texas). Got to go with the RedLine guy on this. By the way, lower viscosity is more horse power. The article points out that you can mix different weight oils to get what works best. The guide is 220 max (ideal) to 240 max at the upper limit.

Mike

Cobra4B · #15 08-31-2009, 12:11 PM

Quote:

Originally Posted by PanozDuke

Brian,
Not doing anything special except Valvoline synthetic 10w30. I used to use 15w50 Mobil 1 in another 302 and had high oil temps (over 240).

Thicker oil actually causes higher temps from friction created from flow resistance. While you need to ensure an adaquate lube film, higher than necessary viscosity actually creates more friction and this is shown by higher temps. High oil temps break down the oil faster in geometric proportion to temp increase. Higher oil temps also cause rotating assembly failures due to metal fatigue and higher rotation resistence at the bearing surfaces and greater frothing. I'm not an engineer, but I did read the Oct Grassroots article- made sense to me and I'm seeing the lower temps. When I hit 218, ambient was 103 (Texas). Got to go with the RedLine guy on this. By the way, lower viscosity is more horse power. The article points out that you can mix different weight oils to get what works best. The guide is 220 max (ideal) to 240 max at the upper limit.

Mike

Mike what's your motor setup? I understand all of what you've said about oil etc. I've ordered a case of Amsoil XL 10w40 synthetic. It's worked well for me in my Corvettes and should be a good compromise between the 30wt and 50wt.

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