AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
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Just to help you with the timing
Your rpm at 60 with say 28s and a 3.91 will be about 2816 with zero slip. So depending on the efficiency of the TC, your Rs might be around 3100. Your engine will want a total timing at that rpm of about 45 to 50 degrees, possibly even more. So if you don't have a Vcan on that D, your engine is gonna consume a lot more fuel than it needs to, and a lot of it will be burned in the exhaust ports and headers. That's gonna create extra underhood heat, and that hot air is gonna go straight down into the intake manifold. Extra timing, allows leaner running, and that reduces the heat. Rich-running wastes the fuel and increases the cruise temps.
At very light throttle settings, like cruising at any speed over say 40, You have to start the fire quite early, so all the fuel can burn inside the chamber, and all of the energy in the expanding gasses can be delivered to the crank. Or at least as much as possible,lol. There is no benefit to sending high-pressure hi-temperature exhaust gasses into the headers; use up that energy to propel the vehicle, instead of keeping the mufflers warm,lol.
I can give you a recipe that I know works, cuz it's what I run, and my temp is rock-solid.
1)26" A/C rad circa 1973, with shroud, core-support cut to fit,and 7 yes 7psi cap. My hoses are circa 1999, except I have no idea how ancient the lower is.
2)8-blade hi-flo pump with an anti-cavitation plate, and matching Hi-flo 195 stat,
anti-collapse spring in lower hose, 50/50 coolant, semi-restricted bypass hose,
3)a 7-blade hi-attack factory A/C teener fan with a Ford pick-up truck (early 2000s)thermostatic clutch, and;
4) I run this in underdrive cuz I regularly buzz her up to 7000 or more.
5) I removed the license plate holder that the factory stuck sorta right in front of the rad!
6) Fresh cold air into the carb and lotsa cruise-timing.
This on;
68 Barracuda,360, manual trans, 2060@60, about 400 hp, maybe a bit more. Cruises interstates just fine at any speed. Idles all day at 36*C (97*F). Well maybe all-day is a stretch, let's say for as long as it has ever needed to, or several hours in traffic.
Yeah so;this recipe works. My stat runs 205 at the housing, always has. I figure it was defective from day 1, but since it never goes higher, Badaboom, I just run it!
You probably don't need the whole recipe. I like overkill, cuz a new engine ain't cheap.
Because your rad is so pretty I'd be inclined to start elsewhere.But I think RRR nailed it. Sooner or later you'll probably be swapping it out. If/when you do; go big. It's a no-lose deal. If it's too big the stat will take care of things. If it's too small, it was a waste of money.
If it was me; I'd start with removing that trans-cooler, and ditching the electric fan,lol.
What are your cam specs and measured compression ratio, or cylinder pressure readings?
Your rpm at 60 with say 28s and a 3.91 will be about 2816 with zero slip. So depending on the efficiency of the TC, your Rs might be around 3100. Your engine will want a total timing at that rpm of about 45 to 50 degrees, possibly even more. So if you don't have a Vcan on that D, your engine is gonna consume a lot more fuel than it needs to, and a lot of it will be burned in the exhaust ports and headers. That's gonna create extra underhood heat, and that hot air is gonna go straight down into the intake manifold. Extra timing, allows leaner running, and that reduces the heat. Rich-running wastes the fuel and increases the cruise temps.
At very light throttle settings, like cruising at any speed over say 40, You have to start the fire quite early, so all the fuel can burn inside the chamber, and all of the energy in the expanding gasses can be delivered to the crank. Or at least as much as possible,lol. There is no benefit to sending high-pressure hi-temperature exhaust gasses into the headers; use up that energy to propel the vehicle, instead of keeping the mufflers warm,lol.
I can give you a recipe that I know works, cuz it's what I run, and my temp is rock-solid.
1)26" A/C rad circa 1973, with shroud, core-support cut to fit,and 7 yes 7psi cap. My hoses are circa 1999, except I have no idea how ancient the lower is.
2)8-blade hi-flo pump with an anti-cavitation plate, and matching Hi-flo 195 stat,
anti-collapse spring in lower hose, 50/50 coolant, semi-restricted bypass hose,
3)a 7-blade hi-attack factory A/C teener fan with a Ford pick-up truck (early 2000s)thermostatic clutch, and;
4) I run this in underdrive cuz I regularly buzz her up to 7000 or more.
5) I removed the license plate holder that the factory stuck sorta right in front of the rad!
6) Fresh cold air into the carb and lotsa cruise-timing.
This on;
68 Barracuda,360, manual trans, 2060@60, about 400 hp, maybe a bit more. Cruises interstates just fine at any speed. Idles all day at 36*C (97*F). Well maybe all-day is a stretch, let's say for as long as it has ever needed to, or several hours in traffic.
Yeah so;this recipe works. My stat runs 205 at the housing, always has. I figure it was defective from day 1, but since it never goes higher, Badaboom, I just run it!
You probably don't need the whole recipe. I like overkill, cuz a new engine ain't cheap.
Because your rad is so pretty I'd be inclined to start elsewhere.But I think RRR nailed it. Sooner or later you'll probably be swapping it out. If/when you do; go big. It's a no-lose deal. If it's too big the stat will take care of things. If it's too small, it was a waste of money.
If it was me; I'd start with removing that trans-cooler, and ditching the electric fan,lol.
What are your cam specs and measured compression ratio, or cylinder pressure readings?
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