1962 Fuelie idle speed

[Jeremy H.]

What is the idle speed at choke and hot on a '62 360hp with stock internals?

Thanks

Jeremy Hedges
(31711)

[Bruce B.]

Re: 1962 Fuelie idle speed

Jeremy,
The info I have for a 7017360 1962 fuel unit shows idle speed as 700-800 rpm and high idle (on choke) at 1800 rpm.

[Don H.]

Re: 1962 Fuelie idle speed

Jeremy, The ST-12 says fast idle is 1800 RPM (hot engine). I did not find the normal idle speed (warmed up - choke off) but I would say 800-1000. That all depends on how hot it is (air temp), fuel you use, and condition of FI. If it will sit and idle at 800 rpm very long in 90 degree plus temps, the FI is in good shape and you are definately NOT running pump gas. Good luck, Don H.

[Bruce B.]

Re: 1962 Fuelie idle speed

Don,
Interesting info on fuel; The 1962 Corvette owners guide has an octane requirement for the 360 hp and the 340 hp engines of 100-102 octane.
I wonder how many people assumed high test would satisfy those requirements?
My 340 hp 62 has never seen fuel higher then 93 octane in the last 20 years and it runs fine.

Of course octane has been calculated a few different ways over the years but the way I do it is to read whats on the pump.

[Don H.]

Re: 1962 Fuelie idle speed

Bruce, I have been running avgas in my '60 FI for over 25 years. It does get pump gas when on the road and I notice a big difference, especially when hot starting in very hot weather. John DeGregory recommends avgas, Jerry Bramlet says ONLY racing fuel (a recent change). You are definetly doing something right to use only pump gas. Don H.

[Bruce B.]

Re: 1962 Fuelie idle speed

Don,
It's interesting that my 62 340 hp 11.25:1 compression ratio has always run fine on Shell 93 octane or some of the other 92 octane pump fuels.
My only FI car is my present 250 hp 57 Powerglide car. According to the owners manual it is 9.5:1CR and gas octane is not specified.
When I broke in the engine (and the rebuilt FI) I did use avegas (LL100 ?) and it ran great.
Since I drive the car a lot I started using 93 octane Shell gas. The car always starts, has never vapor locked and that is with a very early 4360 unit (POC per JD) which now has a single spider and has a antisyphon valve.
Last summer we had a few very hot days and I drove the car, left it out in the sun with the hood closed and it started just fine. I feel that the way the unit was adjusted by Bob Williams in Sydney, Ohio has a lot to do with it's reliability.

I agree with John and Jerry that avgas should be used but my reason is because it does not contain any ethanol.
Bruce B

[Don H.]

Re: 1962 Fuelie idle speed

Bruce, I am assembling a 7017375 unit that will end up on a '65 (auto, AC . . not exactly flight material). I drive it alot and it will be interesting to see how it performs on pump gas. This is also my first time with a "new style" unit so it has been a learning experience. I am surprised you have no fuel percolation in hot weather with pump gas, that has been my biggest problem in heat. There have been many posts about insulating lines and the unit but so far I have not tried that. Regards, Don H.

[Bruce B.]

Re: 1962 Fuelie idle speed

Don,

One thing I did do is use the 1/8" full gasket which insulates the unit from the intake manifold.
This gasket is well worth the money and should fit the 375 unit.

When I first finished the 57 FI car there were numerous people who told me to only use avgas so as I stated in the earlier post thats what I started with. Later I found out that the people who told me only drive thier cars in and out of a trailor.
I put lots of miles on my cars and enjoy them so the pump gas useage is necessary.
I also have a Goldwood Yellow 65 Coupe, 300 HP automatic (Turbo 350), PW, PS, just a nice comfortable car.
I keep looking for a 63-65 FI unit which I think would look very cool on the coupe.
Good luck with yours

[Don H.]

Re: 1962 Fuelie idle speed

Bruce, I do have one of those full base gaskets but have not put it on my 320 unit. It would not fit the 375 unit as the base gaskets are different. I might try using some type of insulation between the plenum and base plate. Don H.