chessterd5
Well-known member
Yes sir, I agree that is a problem but, it's fixable. It is not however the two major problems that I mentioned before.pmuller9":2rojir89 said:
Another option for a better breathing head?
- Thread starter Sevensecondsuv
- Start date
i found that the powerstroke 6.7 heads for the passenger side match up 97-98% of the way and need only 2 heads and two cuts to work, look at the recent post for my best in class towing section it has the details
https://www.fordsix.com/viewtopic.php?f=2&t=81367&start=150
https://www.fordsix.com/viewtopic.php?f=2&t=81367&start=150
This is the one thing I can't picture sealing up on the conversion. I've read the talk about using plates to bolt to the side of the block and bottom of the cylinder head and grinding the side of the deck out above the lifter bore for pushrod clearance. But, what I can't figure out is how to seal from the pushrod side cover up the side of the block to the deck. It's a rough cast surface there. It's not pressurized, so I'm wondering if the plan was to just use a build up RTV type sealer on the ends like a China wall or actually machine the block and plate to mate better together, or ?pmuller9":c6fuvqd4 said:
I don't see the 6.7L PSD head as viable, unless you're building an extreme race engine, tractor puller, etc.
Firepower354
Well-known member
Doesn't the 300 lifter cover nearly meet the deck?
An aluminum block/wedge shouldn't be a big deal.
The pre-gen 5 ls heads have a smaller headbolt between each intake port at the manifold flange, to draw the cover up.
An aluminum block/wedge shouldn't be a big deal.
The pre-gen 5 ls heads have a smaller headbolt between each intake port at the manifold flange, to draw the cover up.
YesFirepower354":146d9htr said:
The upper two corners are rounded and there is a very small valley making sealing less than ideal at those two spots but a good sealant should handle it.
Aftermarket LS heads also have 5 bolt holes that can be used to pull the cover up tight.
https://www.dropbox.com/s/9yuo17x9ozhwn ... .JPG?raw=1
Firepower354
Well-known member
Those are the ones I meant.
The 4 studs under the intakes(as well as the outer 4), on the aftermarket 6-bolt ones aren't likely relevant.
The newest DI heads eliminated all but the end ones, of the 5, but should still hold a cover.
They reversed the valve layout too, but with a custom cam, intake, header, not an issue, I'd think.
And, with LS3 stuff at 340cfm@.500 that should suffice.
Thoughts on how the short pivot length on the LS rockers, and relatively high lift, works as well as it does? tip travel?
And, thoughts on shifting the bore centerlines in the block, to make "3 groups of 2", more closely matching the head segments?
A .040 over, split .005/.035 is still only taking .020 from the thrust side. Less if the bores are also shifted to the driver side.
All pending sonic check, of course.
The LS roller rockers are frequently used with .600"+ valve lift. I don't see a problem.
If you are doing a 3 segment head, just let each cylinder pair straddle two bores evenly.
You may have to offset the head bolt holes a little.
Something else that should be mentioned regarding the "wedge" at the top of the side cover. It actually is a whole new side cover that needs to be fabricated. This has also been discovered on the Chevy inlines as well when making a hybrid head. Due to the V-style valve spacing from the pushrods, the pushrods are actually moved beyond the deck to literally be on the outside of the engine at or near the deck. So to now be able to fully enclose the lifter area to the underside of the head, a "wedge shaped" side cover will need to be made. Not just a "wedge shaped" piece to fill in the gap at the block/ head mating surface. So it will be a little more involved than people may be thinking, but well within many of the folks skill set to accomplish. Notching the outside of the block along the deck surface may also be needed to have adequate pushrod clearance to prevent binding or rubbing the block as the pushrods move throughout their travel.
Last edited:
This is what the notch for the LS3 head in the 300 block looks like.
Firepower354
Well-known member
Of course. I meant "wedge" as in tapering from the bottom of the lifter cavity.
It's not gravel driveway type work, but well below the level of the Sizemore head, or some of the cool same-era stuff in the warehouse when I was at Batten. SBC head converted to U-flow with a HUGE intake port brazed in on the wrong side of the head. 4cyl sprint stuff, I think. etc
That wasn't directed towards anyone in particular. It's just that with the hybrid head discussions that have gone on here recently, very little subject matter has been discussed past making the cylinder head. While a few of us do know what all else goes into finishing out a hybrid head project, many do not. Thanks Paul for taking the time to post a picture of the block mods required for the pushrod relocation phase of a hybrid head install. Now, many that aren't familiar with what was meant by the "wedge" modification necessary, hopefully the picture posted will start to fill in the blanks for those that couldn't quite picture was is needed.
Firepower354
Well-known member
One lad, with cool toys, did a splendid job, even if it was for the "other guy's" engine.
Firepower, What kind of engine do those covers fit? 292 XFLO?
Firepower354
Well-known member
I like.