Pump gas in a SD 421 engine?
 

I am looking real hard at a 62 421 Catalina, ad 1969201, and I went over and heard it run and talked to the guy that built it. The engine is brand new built and is an old 4-bolt 421, this is a pro street car. They fired it up and it is a bad boy, looks and sounds like one of the old B/FX cars. It is supposed to be a 305 duration cam with 11 to 1 compression. I don't want to have to drive 60 miles to the nearest drag strip to get racing fuel for this thing and I just wonder if these octane boosters that you get at the auto parts stores is any good. Most of the stuff I read on the internet about these boosters is from guys who use it in their new BMW, totally different car than what I am looking at. I just want to drive this thing two or three times a month. Any advice?? Thanks.
Rudy

11-1 is right at the cut off for pump gas, I have run pump gas in a 11-1 motor brielfy but I wouldnt advise it.
What I did most of the time was use a mixture of race gas and pump gas.

And no......

Them octane boosters u get at your local parts house do nothing >pure snake oil :wink:

Now if live close to a small airport or a crop duster airport you might be able to get your hands on some av gas.


Goodluck with that pontiac>Cp

x2,use vp 110 and mix it with 92 street fuel.

421
 

Go to E85

Buy a 55 gallon drum of good fuel and keep filling her up!

If the timing is set correct and the car has a good working cooling system you should be able to run pump gas 93 octane.

The other thing to look out for is how they calculated 11 to 1.