C1 Fuel Injection Octane needs.

[John S.]

Re: C1 Fuel Injection Octane needs.

I have been reading this thread from the beginning with interest. Long thread with many many valid points made by most if not all posters. Below is a few things I have learned in the last year with my fuel car. Yes that is right, I have only owned a fuel car for a year in my life. Wanted one since I was a kid and almost had myself convinced not to get one from the fuel and driveabilty stories I had read. Anyways, here it goes.

Car is a 65 fuelie that I believe has never been apart. Still has the original .018 head gaskets on both sides. More then one knowledgable NCRS members have looked at and believe the intake gasket to be original also. Unit itself was gone thru a few years ago by Chris Wickershim in Pasadena. He then tunes it to run on pump premium.

As to the octane question posed by the OP I have had zero issues with detonation. Drove the car in 100 plus heat with engine temps near 210 with no noise.

Percolation at those temps is another story. Car drives fine when on the road but does not like to idle. Have to keep the revs up to 2000 or more to keep it running. Have even been stuck in traffic having to do that. Problem is the temps keep climbing while doing this. Back on the open road and it cools back down.

I did fill up with 16 plus gallons of VP racing fuel last July to help with percolation. Percolation did not disappear completely but was not as bad. Two things I did note while running on the race fuel. First off the car did not run as well overall on the race fuel as it did on the pump gas. I attribute that to the unit being tuned to run on E10. Second off, after running the race fuel to empty I noticed a completely different color on the exhaust tip. Color was a light blue to tan look and very clean. Wiping with fingers left almost nothing on the finger tip. Running the E10 the exhaust tips are a sooty black color and transfer to finger tips very easy.

I have become more accostumed to starting characteristics of me car on the E10 and can live with it. I do take John D.'s advice and drive my car on a regular basis. Easy to do in So. Cal. I learned a long time ago that the worst thing you can do to a car is let it sit for extended periods. Newer cars seem to tolerate it better, but classics need to be driven and maintained.

As to my car, I have already Top Flighted and plan on a PV then Duntov. Once that is accomplished I will probably go thru the insulation of the fuel line process to help with the summer driving.

My advice to anyone hesitating to buy a fuel car because of the horror stories is to go for it. Buy as original as you possibly can and if you need to get the unit worked on, do so by any of the reputable rebuilders. You will love the way the fuelie performs if it is anywhere near original. Just a blast to drive!

[Richard S.]

Re: C1 Fuel Injection Octane needs.

Duke,

Yes, you are correct, I have chosen the VP 110 octane. My question was, of the three options listed which was the best and what were the differences. Based upon the responses, I feel this is the best option for me. Last year my wife had to push the Vette while I popped the clutch and then drove around the parking lot with one foot on the clutch and the other on the gas trying to keep the revs. high enough to keep it running. In the mean time I had to reach over, open the passenger door as she jumped in the car when I came around for the second time. Other times I have had to just let the Vett sit until the evening to restart. Since I know this happens every time I drive over 35-40 minutes in the summer, I do not consider ordering my own fuel to be an inconvenience, all things considered.

[Timothy B.]

Re: C1 Fuel Injection Octane needs.

Richard,

LOL!! You actually got your wife to push the car while you sat inside and popped the clutch. I bet you had to spring for some good lasagna and wine that night. My wife would probably throw something at me if I asked her to do that.

[Richard S.]

Re: C1 Fuel Injection Octane needs.

Tim, This was the 1st. time that the battery was actually dead before I could get the engine restarted. My wife does not drive a stick thus, I am the driver. All in all, I know that she would never have been able to operate the clutch and keep it running but since we were on a slight decline, it gave her a few extra HP. The interesting thing was that after it restarted and I kept about 2500 rpm's at each red light, It drove fine all the way home with a perfect idle when we arrived. I turned the engine off and it restarted with no problem. Oh, and yes she was somewhat upset-thus the new fuel request.

[Timothy B.]

Re: C1 Fuel Injection Octane needs.

"The interesting thing was that after it restarted and I kept about 2500 rpm's at each red light, It drove fine all the way home with a perfect idle when we arrived. I turned the engine off and it restarted with no problem."

Richard,

Isn't that always the case, when the girls are looking the car never runs right but at home all is well. :-)

[Dan H.]

Re: C1 Fuel Injection Octane needs.

FWIW, I've driven FI Corvettes for 38 years, they were always different from carb Corvettes, but soooo much smoother and quicker. There are hot start issues but are a minor incovenience compared to their performance superiority above the carb equipped Corvettes. They are the high water mark of early technology so very worthy of their high standing in our Hobby. My current 1964 FI Coupe has run flawlessly for the last 20K miles on 91 octane Kalifornia gas. I do work on my own FI units, this one is the best, a 380, the most refined of them all. In todays world, if you want to travel beyond the city limits, you need to be able to run your FI on pump gas!!!! If it can't, then park it and go look at it in the garage from time to time. These great cars will run just fine on the current gas, some is better than others, but all will work. GET IT?
Dan

[Michael G.]

Re: C1 Fuel Injection Octane needs.

Exactly.

I am disappointed that yet again instead of an open, honest discussion of how best to deal with the realities of today's fuels, all the old myths and legends get dragged out with the usual threats of 'bad things happening'. This in particular does a disservice to new owners who just want a straight, complete answer preferably with all possible options and a good solid explanation of 'why'.

A challenge was made above asking for any owner to speak up who could operate his FI car on pump gas. This was promptly answered in the affirmative. This apparently has been dismissed out of hand. My own knowledge and observations obviously have no value as do the experiences of others. Why ask the question if the answer is going to be ignored or dismissed? The OP was and apparently still under the impression that his car needs 110 octane or higher fuel to operate satisfactorily.

For reasons unknown, the topic was hijacked to E10 and again the standard myths and misunderstandings dragged out and again real world evidence to the contrary is ignored.

Pretty sad.

Mike, I've read a lot of your posts on this subject, both here and the other forum. I don't believe I've ever read anyone try to ignore your input. In fact, I'm sure everyone here has heard of fuelies that run well on E10. A few have posted here. So it is possible that a particular fuel injected car can run well on some version of E10, in some climate. No one is really arguing that point with you. No one is saying your "own knowledge and observations obviously have no value". They do, they're just not the whole story.

We respect your input and your right to hold your opinions, as well as to support them with concurrence from other owners. That doesn't mean that we agree, or that those few data point you present encompass the whole of the experience in the fuelie community. Many others have different experience, significantly different experience. Three of the most respected experts in Rochester fuel injection, guys who have dealt with more FI units than the number of members who use this forum, have stated opinions here that differ 180 degrees from yours. Those guys opinions wield a lot more clout than yours, because, primarily, they have one hell of lot more experience than you. Lots and lots more data.

If you are going to recommend anything to a new fuelie owner, why would you choose to select the path that most fuelie owners and the most respected experts in the field say is the less desirable course of action? It is, based on lot and lots of data, a bad idea to tell the new owner to use E10 pump gas in a fuelie without making him or her aware that there are potential problems with that choice. Not guaranteed problems, mind you, but situations that have very, very frequently occurred and continue to occur every day. As I said early on in this thread, let the guy try E10, who knows, it may work, but make sure your prepare him for the most likely scenario, i.e., percolation, erratic idle, stalling and hard starts.

You have your opinions on ethanol. You are welcome to them, but you'll never convince the guys on this forum that "hundreds, or even thousands" of fuelies run well with any amount of ethyl alcohol in the tank.

[Michael G.]

Re: C1 Fuel Injection Octane needs.

Whoops, what happened to Jerry's post? I wrote a reply, but the post disappeared in the two minutes I was writing!

Thanks,

[John D.]

Re: C1 Fuel Injection Octane needs.

Duke is correct about the effect of placing insulating sleeves on the fuel lines and filter of an FI engine. I was able to significantly lower the temperature of fuel entering the fuel bowl by insulating the lines all the way under the battery to the frame. Before insulation, the fuel was being heated to 170 degrees as it passed the exhaust manifold, so I had the typical problems with idle and hot starts when the ambient temperature exceeded 85 degrees. Those problems were significantly worse with E10.

Luckily there is a station that sells ethanol-free gas about a mile from my home, so I didn't have to use E10 much, unless I went on trips.

Since the insulation was added, I can put just about any gas in it without problem, even when its over 90 degrees outside. I still tend to use ethanol-free 91 octane when I am home, but I often drive that car 250 miles to Detroit, in the heat of Summer, refilling with E10, with no issues.

I have not yet altered the fuel system on my blue car. That car normally runs wonderfully, because I use only 110 racing fuel (or a mixture of 110 racing fuel and ethanol-free 91 octane) in it. Unfortunately, last summer I put 10 gallons of 93 octane E10 in it when I got to Detroit and couldn't find any racing fuel. It ran fine on a 90 degree day for a few miles, until the E10 got to the fuel unit, then the car stalled as I was making a left turn in front of traffic....I don't use E10 any more. That car's now finished its Duntov, so the insulation will be going on it in a few weeks.

Good info Michael. Here's one for the gang who own a 59 to 62 fuel car. ALL the repro fuel lines that go from the engine fuel pump to the FI filter are made incorrectly. They hug the valve cover big time and at one point near the firewall I have these lines almost touching the valve cover.
At a Pittsburgh chapter judging school this past year we were lucky enough to have Ron Horacks original 60 fuel car on display. Along side of it was another chapter members 59 or 60 show car running a repro line.
Those two fuel lines-original and repro aren't even close. The original is far off the valve cover and is not hitting the front of the cylinder head.
Still all these lines should be insulated as the gas is boiling before it even hits the fuel unit.
Gary Chestnut told us about an insulation he found that works wonders. I have the info buried here but maybe Gary would tell us again. JD

[Michael W.]

Re: C1 Fuel Injection Octane needs.

You have your opinions on ethanol. You are welcome to them, but you'll never convince the guys on this forum that "hundreds, or even thousands" of fuelies run well with any amount of ethyl alcohol in the tank.

Michael-

Please find one post where I suggested using E10 or any post where I recommended any particular fuel. I deliberately chose the term 'pump gas' in my original question. This includes 100% pure gas. While I strongly believe many carbed Corvettes can operate trouble free on E10, I've learned that many in the south, particularly Florida can run into the percolation problems with it. It would be interesting to take a tank full of summer gas from here (Ontario Canada) to Florida in the summer to see if the cars run any better with it.

The subject at hand is whether it is mandatory to use fuels other than pump gas (avgas, 'racing gas', homebrew, etc.) to avoid percolation. For as many that have said 'not possible to use pump gas' there's an equal number that have confirmed that they indeed can and do. It happens that this matches with my own observations. Duke has proved valuable info regarding an insulation scheme that appears to be a real fix for the issue rather than the band-aid use of fuels that are inconvenient if not illegal or impossible to find.

There are a few posters who have tried to hijack this discussion with storage issues with E10, as if that's not been beaten to death enough times. Not interested.

[Duke W.]

Re: C1 Fuel Injection Octane needs.

Here's the thread from about 18 months ago that has lots of good temperature data including before and after applying insulating tape. I was surprised how hot the front of the frame mounted fuel pipe runs, but it probably picks up a lot of radiant heat from the exhaust manifold. Insulating this area alone may have a significant mitigating effect on percolation.

Another way to insulate may be to use loose fitting insulation sleeves - like the one on the temperature sensor wire that is secured to the RH inside valve cover screws on small blocks.

When you compare measured temperatures to the gasoline distillation curves in the Chevron document, it's clear why percolation is a problem, but a little creativity with some insulating material can have a signficant positive effect.

https://www.forums.ncrs.org/showthre...r-temperatures

Duke

[Michael G.]

Re: C1 Fuel Injection Octane needs.

I deliberately chose the term 'pump gas' in my original question. This includes 100% pure gas....

Your stance on E10 has been frequently and vigorously defined both here and Corvette Forum; I'm not sure its necessary for me to list all of your posts on this subject in order for us to garner your position. If you are now including 100% pure gas in your "pump gas" definition, that is a major departure....I wouldn't say that 100% pure gas is a very common pump gas, though.

"The subject at hand is whether it is mandatory to use fuels other than pump gas (avgas, 'racing gas', homebrew, etc.) to avoid percolation. For as many that have said 'not possible to use pump gas' there's an equal number that have confirmed that they indeed can and do. It happens that this matches with my own observations. Duke has proved valuable info regarding an insulation scheme that appears to be a real fix for the issue rather than the band-aid use of fuel that are inconvenient if not illegal or impossible to use."

With the insulation that I devised and Duke mentions, fuel temperatures entering the fuel bowl are reduced enough that ethanol-free gas of octane level above 91 works just fine, with no appreciable detonation or evident percolation. Even E10 works fairly well with the insulation today, but, in severe temperatures or on long drives, its not as effective as alcohol-fee gas. I'm going to guess that with the addition of the heat shield shown in the latest Restorer, even E10 might work fine. However, as Jerry Bramlett may wish to comment, there are other corrosion and gunk build-up concerns with E10 in Rochester FI fuel bowls that may preclude its frequent use there.

[G B.]

Re: C1 Fuel Injection Octane needs.

Whoops, what happened to Jerry's post? I wrote a reply, but the post disappeared in the two minutes I was writing!Thanks,

Mike, I deleted my own post early this morning because it was a smart-ass remark. I try so hard to be good, but sometimes I get my little feelings hurt and the old Jerry comes out.

I've always appreciated your posts because they are courteous, factual, and precisely worded. Mine.... well, not so much. I type like I talk, which isn't a compliment.

[Joe L.]

Re: C1 Fuel Injection Octane needs.

If folks with 57-65 FI's live in California, they better be able to make them run satisfactorily on E10 because finding "pure gas" is very difficult. For all practical purposes, the only options are "racing fuel" and aviation gasoline. It's illegal to use aviation gasoline in a car and about the only way anyone is going to get it is to pump it into gas cans. Most airports are not going to pump it into a car for fear that some pilot will see it and turn the FBO in. Many pilots are very sensitive to this issue because they feel that the illegal use of aviation fuel in cars gives the EPA another "tool" to use against general aviation in their quest to get leaded aviation fuel banned even before their is a viable alternative available. The EPA is already pushing VERY HARD to get leaded aviation gasoline banned nationwide even if no alternative fuel is available, effectively shutting down general aviation.

[Michael G.]

Re: C1 Fuel Injection Octane needs.

Jerry, good to hear from you, I hope all is well.

My first reply to the now-disappeared post was also a bit facetious, as you (or, more likely, your auto-correct) had misspelled "anecdotal" experience as "antidotal" experience. I just mentioned that the mistake was very appropriate, as much of your experience with FI units was in providing an antidote for units "poisoned" by Bubba's tinkering and stuff...

By the way, both the units you did for me have been running great....

Thanks,