does anyone have an opinion on the ideal cylinder head temp of a T1 engine (1776 spec with porsche fan shroud and 44 weber carbs, most overheated cylinder number 2??)
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does anyone have an opinion on the ideal cylinder head temp of a T1 engine (1776 spec with porsche fan shroud and 44 weber carbs, most overheated cylinder number 2??)
when i raced a 356 in e production with cyl head gauges, with 12.5 compression. down the straights it would go to 350, that was what we wanted. but that was at wot. bill
For the case an all internals isn't 225
He's talking CHT not oil temp, I think.
According to VDO - a type 1 cylinder head temp gauge, mounted under #3 plug, will read 275 to 325. A type 4 engine will run 350 to 375 degrees.
They suggest #3 plug mounting location because that is the hotest point for our engines. Mounting a sensor on other studs or mounting surfaces will give a lower reading. My type 4 runs 360 on the freeway on a hot day, instantly cooling to 350 or less when not on the freeway. 350 is normal even on a cold non-freeway day.
They suggest #3 plug mounting location because that is the hotest point for our engines. Mounting a sensor on other studs or mounting surfaces will give a lower reading. My type 4 runs 360 on the freeway on a hot day, instantly cooling to 350 or less when not on the freeway. 350 is normal even on a cold non-freeway day.
David,
You're right on the temps but I believe the Porsche-style fan shroud changes the cooling direction so that #2 cylinder is the hot one.
Don't quote me on that...;)
You're right on the temps but I believe the Porsche-style fan shroud changes the cooling direction so that #2 cylinder is the hot one.
Don't quote me on that...;)
Its #3 that's hot on a 356/912. That's also where the heads crack too if they're going to.
I was told it was #4 as the hot one, I have the 911 shroud. Mine runs 230-260 on number 4 in cruise and normal and somewhat spirited driving.Number 3 does NOT get hot with a 911 shroud.
It will get over 300 or more idling for extended periods in traffic.
A/F is about 12:1 almost all the time.
Hope that helps.
It will get over 300 or more idling for extended periods in traffic.
A/F is about 12:1 almost all the time.
Hope that helps.
What still blows me away, is when I come off a hot freeway run with the CHT at 360 or so, and run down a short exit ramp to a red light. By all rights, that poor engine should be "boilin"! But the temp goes way down just sitin there at idle. Air coolin' is counter-intuitive!
Danny enlighten us here, you say: ...... "Somewhat spirited driving" So is that when you have to pull your shorts out of your crack ?
If it's hotter under #2 CYL. somethings wrong. lose head? bad valve ?
something like that..
By what I have been told 325 is good and 330 is ideal for better gas millage at full speed under a full load but you will need a modified oil cooler to do that.
I came across a good combo on my 1760 cc 74 stroke x 87 bore set up I'm using a T-4 oil cooler and the stock type one fan shroud with the bump out oil cooler tin. The heater pipes air blocked off and diverted down onto the heads . The engine temps have been excellent but with the bigger valve heads knocked the gas millage back a bit on the last upgrade. now only 38 mpg better power but worse millage. And a good dizzy is a must the (p) vacuum type would be best. I'm using a vw vac type and still doing pretty good
something like that..
By what I have been told 325 is good and 330 is ideal for better gas millage at full speed under a full load but you will need a modified oil cooler to do that.
I came across a good combo on my 1760 cc 74 stroke x 87 bore set up I'm using a T-4 oil cooler and the stock type one fan shroud with the bump out oil cooler tin. The heater pipes air blocked off and diverted down onto the heads . The engine temps have been excellent but with the bigger valve heads knocked the gas millage back a bit on the last upgrade. now only 38 mpg better power but worse millage. And a good dizzy is a must the (p) vacuum type would be best. I'm using a vw vac type and still doing pretty good
Alan, just driving normally with occasional full throttle fun!
If I drive it like I stole it, it will stay closer to 300, and go up to 340 or so in REALLY hot, humid weather when idling long. As long as I am underway, head temps are not a problem.
If I drive it like I stole it, it will stay closer to 300, and go up to 340 or so in REALLY hot, humid weather when idling long. As long as I am underway, head temps are not a problem.
As long as it stays well under 400 that sounds pretty decent ,from what I have been told.. But I have set 350 as my mid summer limit...
You could say Im' babying it. But I want my cars to stay OK..
You could say Im' babying it. But I want my cars to stay OK..