Author Topic: av gas yes or no  (Read 13275 times)

fireZ

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av gas yes or no
« on: June 21, 2007, 01:45:23 AM »
I am wondering if 100 low-lead fuel that is meant for small aircrafts is a good idea to run in a stock 68-302 car. I have read some articles that say it is not good for the seals in a DZ carb.
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JohnZ

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Re: av gas yes or no
« Reply #1 on: June 21, 2007, 07:10:37 PM »
100LL won't bother any seals or gaskets, but your local airport FBO probably won't let you pump it into your car; legally it has to go in an airplane or in a container. You really don't need it - a stock 302 will run fine on pump premium if it's tuned properly.
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lakeholme

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Re: av gas yes or no
« Reply #2 on: June 21, 2007, 09:34:13 PM »
And have you priced aviation fuel???  AirNav has a feature for private pilots on fuel prices  They're suffering, too.  John's right! A tune-up would be cheaper and run just as well.  There are a couple of threads here on CRG about high octane and the consclusiion is always, "Why more than premium?"
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sd1968z28

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Re: av gas yes or no
« Reply #3 on: June 21, 2007, 09:49:00 PM »
there is no way in the world you can get optimun performance on pump gas. 11 to compression 7000 rpm do not mix.
fine for crusing but not for full throttle blasts it just dosen't run the same!

Chris_Pisane

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Re: av gas yes or no
« Reply #4 on: June 22, 2007, 12:54:19 AM »
I run it. The lead is actually supposed to be good for the carb because of its lubrication qualities.

 I talked to a race fuel distributor years ago and he said just make sure  you use more of the av gas than premium gas or you are wasting your money.I also talked to a local drag racer and dealer mechanic who uses it in his drag car.He pulls  the engine apart about every 2 years and says he has seen no sort of problem whatsoever.

 I have run it in my 69 z/28 for 12 years,no carb problems.I could never get mine to stop spark knocking under a load  till I used the Av gas.I also believe the av gas wont go bad as fast as the pump gas you get nowdays.

I also  firmly believe in and use silicone brake fluid and sea foam. My 2 cents worth.
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fireZ

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Re: av gas yes or no
« Reply #5 on: June 22, 2007, 01:52:19 AM »
Thanks for everyones thoughts on AV gas. I can buy 100 LL for about 25 cents more a gallon as compared to Sunoco 93 so I guess it is worth trying in my 68 Z .
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camaromikey

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Re: av gas yes or no
« Reply #6 on: June 22, 2007, 02:41:51 AM »
Sea foam is the greatest stuff on the market. Its one of the few that lives up to what it says on the can.

sam

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Re: av gas yes or no
« Reply #7 on: June 22, 2007, 02:44:06 AM »
Let us know how you make out.  Sam

GaryL

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Re: av gas yes or no
« Reply #8 on: June 22, 2007, 04:07:26 AM »
there is no way in the world you can get optimun performance on pump gas. 11 to compression 7000 rpm do not mix.
fine for crusing but not for full throttle blasts it just dosen't run the same!

Sorry, you are wrong. As JohnZ says a stock 302 properly tuned runs excellent on 93 octane. This is an old tech engine. The 30-30 cam makes this whole thing possible. The dynamic compression on a stock 302 is like in the 7's.

I use silicone brake fluid also. Never tried Seafoam. What does it do?
« Last Edit: June 22, 2007, 04:09:16 AM by GaryL »
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bertfam

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Re: av gas yes or no
« Reply #9 on: June 22, 2007, 04:32:52 AM »
Gary,

You asked:

Quote
Never tried Seafoam. What does it do?

Apparently it stinks up the neighboorhood!!  :o

Click HERE.

Ed

Flowjoe

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Re: av gas yes or no
« Reply #10 on: June 22, 2007, 06:14:29 AM »
I'd never heard of sea foam until I read this thread over at Nasty Z/28 http://www.nastyz28.com/forum/showthread.php?t=89103&highlight=seafoam.

I have run my '69 Z on Pump premium since the motor was rebuilt  in '85 (bored .030 and running 11:1 compression on stock heads).  Until 2003 it had a single 4bbl (650 dbl pumper until '90 and the 4053 after that) and the cast iron exhaust manifolds with the "140" off road cam (what can I say..I was young and "stooopid" in '85 - bigger is better, right?)...as long as it was tuned it ran fine...compression was all blown off at idle and just off (of course that is also why it wouldn't pass smog back in the day ;D).  It now has a cross ram and headers with the "140" and still runs well on 91 octane pump gas.  Have dumped 100 octane racing fuel in a few times and it didn't really seem to make a difference (although the exhaust smelt better). 

camaromikey

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Re: av gas yes or no
« Reply #11 on: June 22, 2007, 08:02:04 PM »
I watched a guy do the same thing at the Parts store i work at. I sold him a can of sea foam and he went out and dumped straight in the carb of his 87 C1500. It caused a white out acrossed my parking lot and the street in front of my store. That not how you're suppose to use it. Its' a fuel system cleaner that boaters developed. You pour it in your gas tank or let the enigne suck it through a vaccum line. It cleans the carb or injectors, psitons, and the valves. I run a 600 cfm holley on my car and something got gummed up inside. Alls it took was a can sea foam and a tank of gas and it cleaned itself out. You can also use it as a motor flush.

hotrod68

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Re: av gas yes or no
« Reply #12 on: June 23, 2007, 01:43:49 AM »
104+ octane booster works great with pump premium, but don't get any on your fingers--they'll stink for 2 days! My experience has been there is no way in hell you can run a true 11:1 engine on 93 octane gas without retarding the timing so far it gets sluggish--even with a 140 cam, much less a 30-30. You might get away with it with aluminum heads and sloppy blueprinting, but a true 11:1 will rattle like Grandma's false teeth in a snowbank.
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GaryL

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Re: av gas yes or no
« Reply #13 on: June 23, 2007, 04:05:08 AM »
104+ octane booster works great with pump premium, but don't get any on your fingers--they'll stink for 2 days! My experience has been there is no way in hell you can run a true 11:1 engine on 93 octane gas without retarding the timing so far it gets sluggish--even with a 140 cam, much less a 30-30. You might get away with it with aluminum heads and sloppy blueprinting, but a true 11:1 will rattle like Grandma's false teeth in a snowbank.

Do you own a anything with a 302 in it? I do and it is built stock and tuned as JohnZ says and it runs just fine on 93 octane. #72 primary jets, 36* total at 2800 rpm. AC45 plugs and 15* vacuum advance at idle. The factory setting was 4* initial. How far back do you think it needs to go?  And by the way the way the quench is approx .05". The factory set these engines up for smog and ran them lean and hot. I am not trying to argue but my 302 runs fine. You are correct with a more moderrn cam selection. Please go over to Team Camaro and read on the subject.
« Last Edit: June 23, 2007, 04:06:55 AM by GaryL »
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Flowjoe

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Re: av gas yes or no
« Reply #14 on: June 23, 2007, 06:15:18 AM »
104+ octane booster works great with pump premium, but don't get any on your fingers--they'll stink for 2 days! My experience has been there is no way in hell you can run a true 11:1 engine on 93 octane gas without retarding the timing so far it gets sluggish--even with a 140 cam, much less a 30-30. You might get away with it with aluminum heads and sloppy blueprinting, but a true 11:1 will rattle like Grandma's false teeth in a snowbank.
I used to run 104+ and the 108 octane boost products...thought I needed them.  Found out that they leave a lot of deposits on the spark plugs (just think what the rest of the combustion chamber looks like) then I  found a better carb guy and tuner...haven't run that stuff in years and the car runs great.