What do you guys think?..........87 or 93 octane gas from a pump...for my 71........

[71BroncoBoy]

I have a 71, 302ci, Holley 4 Barrel Carb, I drove it home when I bought it from Georgia a few days ago....I figured the first fill up I should put premium in it...but ever since I put the 93 in it is having trouble starting..is this the reason why its not strating?....should I siphon the 93 out?

 

[72bronco]

The octane rating of your gas shouldn't cause it to not start. I think your problem lies elsewhere. However you're wasting your money on high octane gas unless you run a high performance engine that requires it. Just go with regular unleaded.

 

[Brewbro21]

I agree you're wasting $$$ with high octane gas. Unless you're running a high performance engine or maybe, maybe, fuel injection I'd run regular.

 

[bsaunder]

For best power and economy, run the lowest octane rating you can without pinging. The energy/oz is actually lower with higher octane. When you increase the comnpression, advance timing etc for higher performance you can actually cause the fuel mixture to burn too fast and cause it to ping, hense the need for higher octane levels as it controls the combustion rate.

For the post at hend - there's soemthing else wrong as the octane rating won't cause it not to start.

 

[302fix]

If you don't know alot about the history of this vehicle:
Always remove the gas tank and either have it cleaned out professionally or replaced. For these bronco's it's easy and pretty cheap.

Replace the plugs, wires and distributor cap (maybe coil too).

If you have points in your 71 I'd highly recommend replacing them with something else. I use the pertronix and it is a huge improvement.

My best bet for it not starting is the points are fried. If not that it could be the fuel pump (another cheap and easy replacement).

After you address these relatively cheap and easy adjustments then the checkoff list is drastically narrowed down to timing or carburation (which makes me think hmmm - might just be a bad choke).

Good luck. This is the fun stuff.

 

[302fix]

Just saw your choke post.

That would cause you to be not starting up.

Step on the gas once and see if the choke closes. If not, you'll need to get that adjusted or replaced.

If you have some time and money (that's all it takes right) I'd pop the carb off and send it in for a rebuild. You're going to need it someday anyway right, so why not just get it done now and know it's right:
http://www.ponycarburetors.com/