Octane Boost question

[toddnyc98]

Hi, newbie classic muscle car owner here in beautiful Newark, NJ. I just bought a 70 cuda 440. Haven't gotten it yet; coming from Des Moines to here in Newark early next week. Guy who inspected it said I should use Royal Purple Max Boost as octane boost. Should I use an octane boost or lead additive?

[Chryco Psycho]

Lead additive is to protect the valve seats in the heads , they will last a long time without lead & if hardened seats were installed there is no reason to use lead at all .
It depends a lot on the engine build what octane is needed , I have Run well over 11: 1 compression on pump gas but using a long duration Cam & closed chamber heads with Quench , , timing can help , 4 spd helps for sure as you can control load better . You may have good fuel there such as Sonoco Blue , a lot of Octane boosters have very little effect .

Wlecome to the site from Panama BTW  & congrats on the purchase 

[toddnyc98]

By Sunoco Blue, I assume you mean 260 GT? There is station 10 miles from me that has it from the pump at $10 a gallon. The guy who inspected my car said I could also do 1:3 mix of 260 GT to 93 octane pump gas. Does that make sense?

[Chryco Psycho]

Yes this makes sense , you can experiment with the mix to control detonation / ping .
See if you can control pinging by only using full throttle above certain Rpm for example , , not sure if you have a 4 spd or auto .
More specifics on the engine build would help too

[Cuda Cody]

Welcome to the forum @toddnyc98     Tell us more about your new car!   

[Topcat]

I've used Redline lead substitute for valve recession prevention.

Torco for as a Lead additive substitute.


By far, there's a major difference on how my engine runs; so much better when I pump it with a high Octane.

I'm running Iron heads so I do need to add Octane if I plan on any uphill mountain roads.
She pings every time at 2,500 rpm going uphill without the real juice. Flat land she's fine on pump fuel.

Iron heads make better thermal efficiency but aluminum dissipates heat better.
There's pros & cons for  either one. But all the aftermarket Guru's will say go Aluminum.

That's  another chapter.

[toddnyc98]

Thanks for the welcome. It's a 70 440 4 barrel, 4 speed AAR Tribute.

[70 Challenger Lover]

A friend of mine has 11.5 to 1 compression in his GTO and it pings like a bastard. He uses about a quart of torco per tank and that is a tremendous help. He also tried Lucas and it was good but not as good as the Torco. Recently he got a five gallon can on 110 octane to mix in and that worked best although it's $13 per gallon in Ca.

I'd definitely use a good lead additive and also use a good oil with high zinc whether you use octane boost or not. I've run many engines with 10 to 1 compression, no octane boost and had zero pinging on pump gas.

[Topcat]

A friend of mine has 11.5 to 1 compression in his GTO and it pings like a bastard. He uses about a quart of torco per tank and that is a tremendous help. He also tried Lucas and it was good but not as good as the Torco. Recently he got a five gallon can on 110 octane to mix in and that worked best although it's $13 per gallon in Ca.

I'd definitely use a good lead additive and also use a good oil with high zinc whether you use octane boost or not. I've run many engines with 10 to 1 compression, no octane boost and had zero pinging on pump gas.

Well said...Blueprint on what I have observed.

I'm at 10:25:1 corrected CR. Hemi Iron heads.
She likes 34 total the most. But at a cost.

[Chryco Psycho]

Great lookin Cuda 

[JS29]

Sharp! looks like a fun ride.      And  to the club.