[silvertermi04]

Ok i think this is where the thread should go if not sorry. My dad and I have a 1972 mustang Mach1 that came with the 302 instead of the better 351W or351C. Well we had it sitting for a while because of problems with the tranny plus since we both got New cars (used 01 expediton super clean and low millage that i got at work. Me and my dad bought for my mom as mothers day present, and i bought the cobra) we were short on the money for fixing it and add-ons. Well as of now we changed the carb as well as the intake, put a AOD tranny (i wanted to to a 5 speed conversion but since my dad will drive it way more than i will the auto stayed.) Long tube headers and new carpet. The next thing will be trying to clean up the wiring as well as some Flowmaster mufflers. The question is How do carb engines react to premium gasoline or even some race gas. It runs good and somewhat smooth. The engine is a tired 302 so hopefully later on i can throw in a roller 302 from a 5.0 Mustang. Does the carb have ro be upfited with better seals for the race gas or higher premium fuel. Im hopping that putting a couple gallons of 100 and the rest 91 on it will smooth the iddle a bit more. Thanks.

[Vettezuki]

Originally Posted by silvertermi04

Ok i think this is where the thread should go if not sorry. My dad and I have a 1972 mustang Mach1 that came with the 302 instead of the better 351W or351C. Well we had it sitting for a while because of problems with the tranny plus since we both got New cars (used 01 expediton super clean and low millage that i got at work. Me and my dad bought for my mom as mothers day present, and i bought the cobra) we were short on the money for fixing it and add-ons. Well as of now we changed the carb as well as the intake, put a AOD tranny (i wanted to to a 5 speed conversion but since my dad will drive it way more than i will the auto stayed.) Long tube headers and new carpet. The next thing will be trying to clean up the wiring as well as some Flowmaster mufflers. The question is How do carb engines react to premium gasoline or even some race gas. It runs good and somewhat smooth. The engine is a tired 302 so hopefully later on i can throw in a roller 302 from a 5.0 Mustang. Does the carb have ro be upfited with better seals for the race gas or higher premium fuel. Im hopping that putting a couple gallons of 100 and the rest 91 on it will smooth the iddle a bit more. Thanks.

You'll probably get a more detailed answer from BRUTAL64 later, but here's my 2 cents.

Your idle quality has nothing to do with the octane rating of the gas you're running. (With the possible exception of very low octane on a very high compression engine, but that's a different story with much bigger potential problems.) Is that gas that's in there "fresh" or has it been sitting in the tank for a year or more? If it has, it may have begun to separate, or there might be a lot of water in it, etc., which would certainly could effect how smoothly the engine is running. Assuming the gas is fresh, the idle quality has to do with the engine and most likely the carb itself.

The only reason to run higher octane fuel is because of higher compression, more boost, and/or more timing. The octane is simply a resistance of the fuel igniting. For example, low octane fuel is dangerous (won't really work) in a high compression engine because it will knock, or possibly pre-detonate, potentially damaging or even destroying the engine. A higher octane will allow the air/fuel mixture to be compressed without spontaneously igniting.

[joedls]

Originally Posted by Vettezuki

You'll probably get a more detailed answer from BRUTAL64 later, but here's my 2 cents.

Your idle quality has nothing to do with the octane rating of the gas you're running. (With the possible exception of very low octane on a very high compression engine, but that's a different story with much bigger potential problems.) Is that gas that's in there "fresh" or has it been sitting in the tank for a year or more? If it has, it may have begun to separate, or there might be a lot of water in it, etc., which would certainly could effect how smoothly the engine is running. Assuming the gas is fresh, the idle quality has to do with the engine and most likely the carb itself.

The only reason to run higher octane fuel is because of higher compression, more boost, and/or more timing. The octane is simply a resistance of the fuel igniting. For example, low octane fuel is dangerous (won't really work) in a high compression engine because it will knock, or possibly pre-detonate, potentially damaging or even destroying the engine. A higher octane will allow the air/fuel mixture to be compressed without spontaneously igniting.

What he said. And to add a little, your car will not run any better without some tuning for high octane fuel. Simply adding the fuel without tuning for it will net you nothing.

[silvertermi04]

OK thanks guys, the fuel in there was old so we drained it, I figured we had to play with the carb a little since its an aftermarket one and we just slaped it on there. My question was more toward if adding higher octane towards a carbed car if there would be any problems. Also was if there is any setbacks towars adding a couple gallons of race fuel to every tank. I think when we do the rewiring im going to ask my dad if we could just do an aftermarket ignitions with wires better spark plugs and cap and rotor.
Do u guys think its worth it getting an aftermarket ignition system like MSD for a mostly stock engine.

[silvertermi04]

By the way thanks for the rest of the answers they answerd, i know the carb needs playing around with as well as finding the best timing for the car and like i said maybe adding the aftermarket wires, plugs, cap, rotor and that thing that bolst to the inner fender well that i just forgot the name of lol

[Vettezuki]

Originally Posted by silvertermi04

. . . My question was more toward if adding higher octane towards a carbed car if there would be any problems. Also was if there is any setbacks towars adding a couple gallons of race fuel to every tank. I think when we do the rewiring im going to ask my dad if we could just do an aftermarket ignitions with wires better spark plugs and cap and rotor. . .

Basically no, no real set back. Simply there's no reason to do it. The energy content of the higher octane gas is not higher, only its resistance to igniting. However, if you have a higher compression motor (I don't know what that one is), the higher octane would let you go for a more agressive tune and make more power, namely with advanced timing. I guess my point is, there's not really any harm in running higher octane fuel on a stock engine, but unless it's combined with agressive tuning, etc., there's no point either. Some might even say that running premium in an engine designed for regular may actually reduce power, mostly because of the way the fuel ignites and the timing curve, but I've never seen any scientific study.

Conclusion. Sure you can put it in there, but unless you do something to take advantage of the higher octane fuel, there's no inherent advantage to putting that gas in.

As for ignition, I'll leave that to the other guys who know way more about that old school stuff. I only know that some serious guys I know seem to prefer Mallory over MSD, but there's certainly plenty of people running MSD.

[BRUTAL64]

I'm not a fan (at all) of MSD!!!!!!!!!

There are some good answeres here. YOU guys are smart.

[silvertermi04]

Thanks to vettezuki, joedls and brutal64. I guess then will keep the 87 fuel on the car. As far as ignition goes then i might look into the Mallory ones. Should i do all the stuff i posted earlier or just wires ????????

[BRUTAL64]

Originally Posted by silvertermi04

Thanks to vettezuki, joedls and brutal64. I guess then will keep the 87 fuel on the car. As far as ignition goes then i might look into the Mallory ones. Should i do all the stuff i posted earlier or just wires ????????

The Ready to Run MSD Dizzies are pretty good. I really like the Accel Multi spark box. I use Accel stuff most of the time.

We sell the Accel Multi spark stuff here. I use the 8 mil Super Stock Spiral wrap wires. The Accel Caps are the way to go.

[silvertermi04]

Originally Posted by BRUTAL64

The Ready to Run MSD Dizzies are pretty good. I really like the Accel Multi spark box. I use Accel stuff most of the time.

We sell the Accel Multi spark stuff here. I use the 8 mil Super Stock Spiral wrap wires. The Accel Caps are the way to go.

Ok so cap and rotor from Accel and wires as well, what about that things thats mounted in the engine bay usually by the passanger fender.