Quickie
 

Does anyone put an octane booster into their fuel mixture and if so, why? Should I be running that in the big block? Thanks a lot.

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72 with 69 grille and custom 73-87 stepside. BIG BLOCK 409, SM465, NP205, 3/4 axles slung under a 5" lift, 112" frame, and 33's soon to grow... "BUILT NOT BOUGHT" ...oh, and industrial paint protecting her body.

I haven't had to use octane booster on my BB and unless you have really high compression (above 10.5:1) you shouldn't need it.

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71 SWB Stepside, was a 250, now is a 402 Big Block with 4 speed and 3.73's

72 LWB 4x4 350 4-speed 3.08's posi wearing army olive drab green (SOLD!)

68 BURB 50TH LOOKALIKE with built 350 4-speed 4.11's and posi

Nah, save your money for important stuff. My 402 runs fine on 87 octane junk.

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56 Studebaker 2 dr Wagon
66 Chevelle 2 dr 4 speed
71 C30 Longhorn
86 Monte Carlo SS
96 Tahoe

If your timing is set properly and the truck "pings", that's a good time to use it, otherwise, you won't benefit at all. "Octane" rating is a fuel's resistance to detonation. 98% of street legal vehicles run just fine with pump gas (93 octane). Like 71402BB said, unless your running 10.5:1, you won't need it.

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Yeah, that's right. My name is Randy too!
WWW.Randysrods.freeservers.com
1970 Chevy C-10 shortstep
30 Ford Model A Coupe 4 inch chop, 350, GMC 671 blower-Hell yeah it's fast!
87 Harley Sportster(couldnt get a 350 to fit)
Self Propelled Lawn Mower
Built in USA!!!!

Virginia Beach, VA.

My 396 has 10.25:1 and i dumpt im the 101 or 104 octane booster a few times,and it acctually ran worse.with my stock 402 i run cheapy crap with no problem.

All right thanks guys. I just wasn't sure because my engine is the second oldest big block you could have and I figured it was built back then to run on the type of fuel they had... leaded.

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72 with 69 grille and custom 73-87 stepside. BIG BLOCK 409, SM465, NP205, 3/4 axles slung under a 5" lift, 112" frame, and 33's soon to grow... "BUILT NOT BOUGHT" ...oh, and industrial paint protecting her body.

is the motor stock and never been rebuilt?

if so, you should have the heads rebuilt with hardened seats or start using an additive like CD-2 Lead Additive (a replacement for lead) or Marvel's Mystery Oil..

the lead used to cool your valves, unleaded gas won't and it will allow your valves to overheat and burn..

other than that, octane booster only needs to be used when the motor needs the extra octane to prevent pinging

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Webmaster: www.GMPerformance.org

Colin: the '09 is stock besides a new Holley residing atop but you made a lot of things much clearer for me. Lead was my main concern and if my engine craved more; I must've used the wrong name when i started talking about octane. I have no ping and she runs strong, you pretty much answered my questions though... THANKS

[This message has been edited by Chevy409 (edited May 12, 2002).]

you're welcome http://67-72chevytrucks.com/board/ubbhtml/smile.gif

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Webmaster: www.GMPerformance.org

I don't know anything about this company but someone posted the site earlier....good reading if nothing else. There is a section about octane boosters.....I think it's the 9th one down.
http://www.badasscars.com/techtips.html#top

[This message has been edited by 1972c10_ohio (edited May 12, 2002).]

My experience with unleaded fuel on leaded heads/stock seats,is that if you are running around town,no long high speed hyway trips/heavy hauling.....you can run many miles on the street without the hard seats. I ran a set of 492 castings 30,000 mi on the street,then sold them to a bud,& he has another 10,000-15,000 on them & no troubles! These are pretty much all city logged miles.......with a little weekend racing(no addatives)...........69

[This message has been edited by 69 longhorn (edited May 12, 2002).]