63FI

I have a question for guys who drive a FI car enough to really know it. I put a lot of miles on my '63 and was wondering if anyone has noticed what seems to happen to mine. About 20-30 minuites after the engine gets up to temperature, it seems like the car runs a little lean. You can notice this while cruising, not WOT. It is fine at WOT. I have it setup more lean than rich and it runs great otherwise. I should mention that I am also running Trick-Flow aluminum heads and a 160 thermostat. Actually , this seemed to happen with Iron heads also. It just behaves like it is a bit lean after running for a while. Otherwise, it runs great. Has anyone noticed this with a FI car?
Thanks, Lou

jerrybramlett

No, I haven't noticed that at all. What are the symptoms that make you think your unit is running lean?

I assume you're running a 7375 unit with a points-type, vacuum advance distributor. Did you calibrate the lean stop setting by trial and error, or did you use a manometer? If you used a manometer, what nozzle pressure did you set at .5" venturi vacuum?

62fuelie

I drive my Fi car almost daily and do not notice this problem. I do notice a problem with vapor locking at hot idle when the car is first restarted. This only occurs in cooler months when the gas formula changes to "winter" gas.

Weasel

I drive mine almost every nice day with no problems. :cheers:

62fuelie

Glad to see that someone else dricves their fuelie on a regular basis. I had mine out this morning for a trip through the drive thru for breakfast.

Do you notice a difference in hard hot starts or surging after a hot start? I do, but as I mentioned in my post it's only when we get the "winter" gas formulation. For some reason they start changing the formula here in September when the temp is still in the 90's. I have fueled up one time since Sept 15, the day they change the fuel formula, and I already notice a bit of a problem I didn't have with the "ozone friendly" fuel we have in the summer.

63FI

Hi Guys, sorry it took me so long to answer. My dial up line has had a crackle /hum on it for a few days.

Jerry, I don't have a manometer, so it has been the trial & error method.
Reason why I feel it runs a little lean when hot is it has a very slight "surge/
pulse when crusing. It is very slight at worse. It is a simular condition when I know it is set up too lean. The car runs great otherwise and only seems to happen when hot. Gets decent mileage with a 4:11 rear also.

62Fuelie, I have never had any vaporlock problems ever. It has always started up very easy even when super hot. I should tell you that I have replaced the cranking signal valve with a electric valve. The only time I turn that on is from a cold start after it has been sitting for a while.

Thanks, Lou

blu62vette

I drive mine several times a week but not quite daily. I have a vapor lock problem but thats about it. It is still 97 today so that means more vaporlock. I have never noticed is as much when the weather is cooler.

Todd.

Rair67

Has anyone here tried 105 octane racing fuel, or one of those lead additives/octane boosters in their fuely?

Just wondered.

Chuck Gongloff

I drive my 63 FI car rarely...about 500 miles per year. Runs well. Use 93 octane pump gas and add some of Jack Podell's octane booster. No ping, etc. I'm running stock 11.25:1 compression. Chuck

62fuelie

Blue62: Interestingly, when it's 97, I have no problem at all. The gas we use here in hot weather, mandated by the EPA, doesn't vapor lock. As soon as Sept 15 rolls around and we go back to the regular fuel I start having problems. I need to stockpile some summer fuel, but that's easier said than done.

rgarrett

I only put about 1000 miles a year on mine, but no problems like you mention. I do however seem to have the vapor lock problem some others have mentioned.

63Corvette

Yep, I run whatever racing gas is available at the respective track. However, I don't run the highest rating, which is usually 116, because My engine is only 12.5 :1, and really doesn't need it. However, it runs fine in the FI, and there is really no observable difference that I can tell.

blu62vette

That is weird. I had the problem just the other day and we should be on winter fuel out here in CA. I am going on a tour of a Chevron/Texaco refinery in early Nov and will get to ask some questions that will be one of them.

62fuelie

The winter fuel is the problem. It vaporizes more easily to aid cold starting. We have no real cold weather here, or if we do have it , it doesn't last long. No real need for "winter" gas.The EPA summer gas does not vaporize as easily to prevent evaporative emissions, but it also doesn't cook off in the FI spider from heat soak. The "reformulated" fuel is a few cents more expensive, so it is only required from May thru mid Sept. My fuelie sure runs awfully nicely on it though. :D