Twin turbo 300
- Thread starter tmc5150
- Start date
There are several issues.
The hydraulic roller lifter is typically taller than the solid roller lifter because of the room needed for the plunger and oil valving.
This puts the connecting bar higher and interferes with the block bosses that the side cover bolts to.
This can be addressed by getting creative with a cross bar or clearancing the bosses or removing them and bolting the side cover some other way.
The Ford 429/460 retrofit hydraulic roller lifters have a spacing very close to the 300 six.
The 429/460 lifter bore spacing is 2.080". I'm not home at the moment to measure the 300 six lifter bore spacing.
The second thing to check is the lifter oil groove around the middle of the lifter body.
It must not go near the top of the lifter bore in the block at full lift with the cam you are going to use.
Open up the side of the main oil gallery so you can see the lifter body alignment.
With the lifter installed see where the lifter groove aligns with the oil gallery at the bottom and top of the lifter travel with the chosen cam.
Another concern is finding a distributor drive gear that is compatible with the billet steel cam gear.
The standard iron gear will not work.
The bronze gear will work but the gear wears fast which is ok for racing but not convenient for a street engine that sees mileage.
A composite gear is compatible and gives long gear life but would have to be a custom item. More research is needed.
There may be another type of steel gear that would work. More research again.
The 300 six use a 16 tooth gear that is not used on another engine V8 or otherwise.
The gear issue needs to be resolved first before ordering a roller cam and lifters.
The hydraulic roller lifter is typically taller than the solid roller lifter because of the room needed for the plunger and oil valving.
This puts the connecting bar higher and interferes with the block bosses that the side cover bolts to.
This can be addressed by getting creative with a cross bar or clearancing the bosses or removing them and bolting the side cover some other way.
The Ford 429/460 retrofit hydraulic roller lifters have a spacing very close to the 300 six.
The 429/460 lifter bore spacing is 2.080". I'm not home at the moment to measure the 300 six lifter bore spacing.
The second thing to check is the lifter oil groove around the middle of the lifter body.
It must not go near the top of the lifter bore in the block at full lift with the cam you are going to use.
Open up the side of the main oil gallery so you can see the lifter body alignment.
With the lifter installed see where the lifter groove aligns with the oil gallery at the bottom and top of the lifter travel with the chosen cam.
Another concern is finding a distributor drive gear that is compatible with the billet steel cam gear.
The standard iron gear will not work.
The bronze gear will work but the gear wears fast which is ok for racing but not convenient for a street engine that sees mileage.
A composite gear is compatible and gives long gear life but would have to be a custom item. More research is needed.
There may be another type of steel gear that would work. More research again.
The 300 six use a 16 tooth gear that is not used on another engine V8 or otherwise.
The gear issue needs to be resolved first before ordering a roller cam and lifters.
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The 300 head has a good exhaust flow compared to the intake and doesn't need the extra exhaust duration in a non racing application.
For a turbo application where there is a good exhaust manifold with fairly long primary tubes, a single pattern cam with a wide LSA that is set 4 degrees advanced opens the exhaust valve early.
This starts the blowdown portion of the exhaust cycle early giving more time to evacuate the cylinder's exhaust pressure to drive the turbochargers.
A longer duration exhaust does the same except it also increases the valve overlap exposing the intake to possible back pressure at low rpm.
The longer duration exhaust seems to work OK at high rpm but it delays the turbo spooling at the low end.
I plan on using the efi manifolds. Probably single pattern makes more sense then. Not racing it but need as much power as I can within reason. There is much more I need to learn about this engine. The sbf has soo much info out there.
I looked up the flat tappet lifters for the 302 and 300. They had the same part number. I guess I need to find an example of the 302 lifter with the link bar. I didn't figure in the lift and the oil groove. They ran 523 lift on the engine masters with a hydraulic flat tappet. I'll have to pull the tappet cover off and have a look when I get time. It's been raining almost every day in the Phoenix area! This is why I left NW Ohio....
I know about the gear material. I tried that bronze material once on my 351W. Destroyed it in 2000 miles. I'm not sure about the composite gear. Have you ever tried one? I figured one off a V6 might work. I guess it's time to look into that too. I wonder what FTF uses?
The bosses would be an issue. I guess I didn't realize the solid roller and hydraulic roller were different heights.
The piston diameter will depend on the bore size for the block.
Bore the block the minimum size needed to straighten up the cylinders. The 300 six has thin wall cylinders and you want as much cylinder wall as possible.
You can also sleeve a block down to 4.00" or even 3.875" using ductile iron sleeves for a very strong cylinder wall.
The piston pin height depends on the finished block deck height. Again just deck the block enough to straighten and clean up the surface.
A deck height of 10.00" will need a piston with a 1.625" pin height to get to zero deck height with the Compstar 6.385" rod.
The compression ratio will depend on the .006" duration cam specs and how much intercooling will be provided.
The actual dish volume will also be affected by the cylinder heads combustion chamber volume.
I can't fit the factory efi intake in the COE doghouse without modifications to the floor. I got a Clifford intake. I guess I have to buy an adapter to mount anything to it..... really? A holes. It has bosses cast into it but not in the factory EFI locations. I don't have a machine shop near by that will help me. So I guess I'll put a Holley terminator or some other brand the carb flange.
I made a mock up engine out of foam and aluminum tape. Took measurements from it . I want to keep it as original as possible. I will repaint it a similar aqua marine color.
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What do you want to use for an intake manifold?
Will you be using a Holley Sniper or some thing similar?
tmc5150- just FYI, if you want to see a list of all camshafts available for this engine, see catalog of conceptual build plans for the bb ford thread, post #5- under the BB Ford heading. Schneider and maybe others will do a custom grind, but be aware that Schneider is out of cam blanks and already has a backlog of backorders. If you want a Schneider cam, figure out your specs and put in the order asap, then expect to wait an unknown period of time.
Firepower354
Famous Member
Clifford still uses the old small base carb mount, so anything else has to have an adapter. Watch how far it sticks out.
The factory EFI lower and a fabricated plenum won't clear?
It's a shame that the SBF guides or a fabbed likeness, or the plastic retainers like Godzilla, can't be used, making lifters cheap and plentiful.
The factory EFI lower and a fabricated plenum won't clear?
It's a shame that the SBF guides or a fabbed likeness, or the plastic retainers like Godzilla, can't be used, making lifters cheap and plentiful.
When to comes to a hydraulic roller lifter, AFAIK no one has used one in a 300 six yet so there are no solid answers.
You will need to get a pair of SBF and 460 hydraulic roller lifters and examine link fit and oil passage location so you will know for sure what will work for you.