300 exhuast
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300 exhuast
I put on a set of Clifford Performance dual outlet headers and combined them into a 3" pipe to 3" catalytic converter and then into a 2.5" Flowmaster 40 series muffler with 2.5" out the back. This exhaust keeps the engine running cool. I say so as I can now place my hand on the intake manifold without being burned and this is after a 100 mile ride on the highway. I didn't loose any low end power(torque). Gas mileage went up and I gained power across the rpm band. Don't worry about loosing torque, simple to say you won't. There has been many an argument about this on this website. Opening the exhaust on this engine brings it to life! Do it and enjoy it!.
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300 exhuast
paulg:
I have a 78 300-6 in an '86 F250 4x4 with the older style intake/1 piece exhaust manifolds. Exhaust manifold is leaking at the heat riser and I want to replace it. I looked at buying the newer style split exhaust manifolds from a yard but how can I use the original intake? Can I put a plate and gasket over the opening in the bottom? My understanding is the split exhaust went only with EFI which (the intake) obviously won't work on my carbed engine. Soooo, can I run a header or split exhaust using the existing old style intake manifold??
Also, I just looked at Clifford Perf and they have a water heated intake. Is it water heated to replace the heat stove/duct from exhaust to air cleaner to prevent carb icing?
Thanks
Skippy
I have a 78 300-6 in an '86 F250 4x4 with the older style intake/1 piece exhaust manifolds. Exhaust manifold is leaking at the heat riser and I want to replace it. I looked at buying the newer style split exhaust manifolds from a yard but how can I use the original intake? Can I put a plate and gasket over the opening in the bottom? My understanding is the split exhaust went only with EFI which (the intake) obviously won't work on my carbed engine. Soooo, can I run a header or split exhaust using the existing old style intake manifold??
Also, I just looked at Clifford Perf and they have a water heated intake. Is it water heated to replace the heat stove/duct from exhaust to air cleaner to prevent carb icing?
Thanks
Skippy
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300 exhuast
I do believe the dual headers on later model F150s will not fit your truck's engine. What you to do is get a single outlet header from Clifford Performance or find another manifold off another truck from the years of 65-79. As for the water heated manifold I have no idea why C.P. calls this manifold water heated. I have seen a picture of this manifold and I don't see how water could flow through out the manifold as it appears to have no water jackets or sockets for flowing water. Also if it does use water to heat itself does it get the water from the radiator?! Does it have freeze plugs to prevent breakage? I don't know. C.P's idea is to keep the manifold hot to increase fuel vaporization (which is a good idea) and promote car de-icing. How they do this with water I don't know.
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Joined: Jan 2000
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From: Dryden, ON, Canada
300 exhuast
The split manifolds will bolt on any 300. You don't need to do anything with the hole in the bottom of the stock intake, it's there so that the exhaust can heat the intake manifold.
Evan MacDonald
82 F100 FlareSide ex. 2wd
MAF MPFI HD 300-6
Hedman Hedder
NP435(6.69 low)
NP205
3.55 Geared ARB'd 9"
Dana 44 TTB
31x10.50/15 Goodyear M/T's
Evan MacDonald
82 F100 FlareSide ex. 2wd
MAF MPFI HD 300-6
Hedman Hedder
NP435(6.69 low)
NP205
3.55 Geared ARB'd 9"
Dana 44 TTB
31x10.50/15 Goodyear M/T's
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300 exhuast
[font size="1" color="#FF0000"]LAST EDITED ON 19-Jan-01 AT 03:25 PM (EST)[/font][p]Clifford's water heated manifolds have a rectangular water passage cast into the underside of the manifold. It has two threaded holes for attaching lengths of heater hose, though they don't include fittings. I assume it's a reasonably standard pipe thread. I haven't hooked mine up yet since the truck drives ok without the heat feature.
BTW, I currently have headers and glasspacks on this engine. Yech. Sounds great as long as you keep it below 2000 rpm. Above that, and it gets really rude and blatty. Kinda like an airplane engine. I'd like to find something that's louder than generic turbos but not this loud...
--sean
BTW, I currently have headers and glasspacks on this engine. Yech. Sounds great as long as you keep it below 2000 rpm. Above that, and it gets really rude and blatty. Kinda like an airplane engine. I'd like to find something that's louder than generic turbos but not this loud...
--sean
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