How are your midyears running on todays pump gas??

[jims427400]

I have been told by my carburator rebuilder that these older cars from the 60's flat out are not going to run well on todays fuel.he suggests mixing racing fuel in w/ todays gas.
He's had several examples of pourly running cars,mixed in racing fuel and problem solved.
Would like to poll everyone currently running original vintage 327s and 427s in midyears and tell how their cars are performing.
And if youve run into problems,how did you resolve them.

Thanks all, Jim

 

[firstgear]

I have been told by my carburator rebuilder that these older cars from the 60's flat out are not going to run well on todays fuel.he suggests mixing racing fuel in w/ todays gas.
He's had several examples of pourly running cars,mixed in racing fuel and problem solved.
Would like to poll everyone currently running original vintage 327s and 427s in midyears and tell how their cars are performing.
And if youve run into problems,how did you resolve them.

Thanks all, Jim

my 327/365 hp runs just fine on Shell 93 octane....no problems....

 

[jimbo64]

My 327/300 hp runs fine on Sunoco 93. We don't mix it with anything. Good luck.

 

[65vettish]

No problems w/ Exxon 93 octane here in Tennessee. Runs like a scalded dog!

 

[67l36driver]

Old Blue runs on any 87 octane available including the 10% ethanol. But then, thats the way I planned the engine build.

Oops, "original".

Now take Corvairs for instance. My 110 hp don't like 87 octane very much. You get pinging if you lug him too much.

 

[IH2LOSE]

1966 427/425 stock configuration with the exception of running the timing slightly retarded No problems with sunaco 94 ultra

 

[cfalson]

327/350, lowered compression to 10:1 runs fine on AMOCO 93 Octane, with 38 Degrees of advance and an agressive advance curve.
charlief
66 Coupe

 

[jims427400]

All your reponces are encoraging.

Anybody w/427 tripowers out there??

 

[BarryK]

Jim

my neighbor had a stock '67 L71 435hp tripower for about 10 years until he just sold it this summer. He just ran regular hi-test that you can get around here - depending on the station it was either 93 or 94 octane.

 

[JohnZ]

All your reponces are encoraging.

Anybody w/427 tripowers out there??

Your 427/400 should run just fine on pump premium; race gas or a race-gas blend only becomes necessary with compression ratios over 11:1 - yours is spec'd at 10.25:1, and most actually measure closer to 10:1.

 

[jims427400]

Barry and John,
I'm sure after I get the bugs(dirt)out of either the front or rear carb,that will prevent the current flooding problem.just a little dissapointed-i was hoping to bolt them on and be perfect.
Oh well,I did buy the car to give me something to play with.

 

[ChuckG]

All your reponces are encoraging.

Anybody w/427 tripowers out there??

My 69 427/400 (hydraulic lifter) engine runs fine on 93 octane. My 63 with 11.25:1 compression runs fine on it too.

I think it's a "non issue". I do occasionally put 5 gallons of CAM 2 in the 63, mainly because I like the smell. Chuck

 

[Kid_Again]

not much to say after JohnZ weighs in but add another vote that my cars run fine on whatever octane is advertised as "premium" around here (91 or 93)

 

[jims427400]

ChuckG and Kid Again,
I'm seeing a pattern here,and I'm not conserned anymore on fuel quality for the BB. Thanks All Jim

 

[435er]

My tri power rattles pretty good on sunoco 94,however a healthy dose of
octain supreme 130 does help but not eliminate.This engine does not like
the timing retarded,it starts,idles and generally runs excellent the way it is
so i run it easy most of the time and leave it alone.The few times its driven
in the spring and fall,for me does not warrent av gas or race fuel.

435er

 

[Kid_Again]

yeah, no big deal, really.....IF you have original, unmodified heads, your timing is correct and you have some detonation, just buy some tetra ethyl lead and add 25% or so of the recommended amount and you'll be pleased with the difference but you sound like you're fine

 

[Viet Nam Vett]

As ststed by Dr. John Z.. My 502 BB runs very nice on 93 Oct ... It does have an aggressive Hyld roller cam..but is built for the street to run on Pump gas as it is 9:25 Comp ratio.

So.. I also would conclude that as stated by John that it is a matter of Compresion..

 

[jims427400]

Kid again,
"tetra ethyl lead" is that the basic lead additive that you buy? or something special?

 

[Tom]

I've been using Shell Preminum in my 1965 300/327. In the 5 years I've owned it, it starts good, and runs good.

 

[Vref]

My original engine does not run that well on 93 octane. I run 100 Low Lead avgas in it from the local airport, Its about 50 cents per gallon more, but It runs excellent.