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Discussion Starter · #1 · (Edited)
Hello Everyone,

I'm a newb to this forum and would like to say greetings you all.

I have owned a pair of GTOs now since 1981. My 1970 car was chosen as the Picture of the week here:


I've only recently discovered that an E85 pump is available not too far from my home here in Utah. I've only dared to run about 60% of my tank with E85 Ethanol so far.

My question is this:

Has anyone here attempted to run a classic 1960's or 70's Goat on straight E85 Ethanol? And if so what did you do to your car?

I've already ordered all the Primary & Secondary metering rods and jets from Carb's Unlimited and am about to embark on an all out assault on the fuel delivery system to support this fantastic and cheap 105 Octane juice. So far with a 60% load of E85 I can run any amount of timing I desire without detonation even though I'm well over 12:1 with the shaved 64cc #12 heads on the +.030" 455 now in my car, Something I haven't experienced since I could legally drive right onto the Ogden Municipal Airports waaay back in the 1980's and pump in some Avgas. It's no longer legal to pump Avgas into our cars here in Utah due to Legislation changes associated with highway taxation.

I've already made Carburetor changes that include the .147" inlet needle and seat, richer primary Jets #79 with # 41b Rods and CC Secondary Rods on a tweaked K hangar to provide .640625" Secondary Rod height per Pete McCarthy's recommendations in his book "PONTIAC Racer's & Hi-Po Handbook."
I'm waaaaay too rich right now and dealing with flat spots in the mid range power band between 2000-3000 Rpm.
So once all the jets & rods arrive next week I'll begin dialing it all in.

Sorry this is so long winded but I was hoping someone from within this forum may already have some input to this endeavor.

And I just want to say a Howdy, Howdy from way out West here in Utah.


Turbo aka Dave Voland

· Registered
84 Posts
I'd like to make the comment that you're probably one of the first to try this, so speaking for myself, I don't have a clue. I believe you're going in the right direction because since the fuel has less BTU's per gallon, you're going to need to flow more of it. But because the octane is higher, you can run more timing. From there, I can't offer any real help. Oh, and if you know how to get in touch with Pete McCarthy, please let me know. Nice guy and knows his stuff.
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