Did you mean valves from AJ41 are longer than those in AJ27?
I checked both part numbers from land rover 4.4 NA engine and from 4.2 supercharged (I think it is the same AJ33S as in XKR/XJR) and for both engines part number is the same.
Is that means AJ33 valves are also longer than AJ27?

If they are I think it will be still manageable.. as I saw they are quite higher above the keepers.. If both valves have keepers groove on the same place I can cut some of the upper part.

 

Very nice site btw.. I found it before 5-6months maybe.. Very nice article about 2 and 4 valvers.

 

The engines are slightly different between Jaguar and Landrover, the valves are indeed longer and the buckets are smaller in outside diameter, so you can’t just swap these. I guess you could shorten the valve, but I don’t know if the shape of the valve to fit the seat is the same, and I guess the tips where hardened. Better to double check this and also the keeper’s height as you say.

 

Thank you avos!

Unfortunately there is no easy (cheap) way to figure out these differences.
I was thinking to buy also camshafts and buckets from LR, to take advantage from slightly wider intake cam (240 degrees for AJ33/41 vs 230 for AJ27)
Unfortunately I should get whole heads, and I will pay much more on shipping costs, than for two old heads.
On other hand I'm ready to pay twice as much but to take valvetrain that will bring most benefits in terms of performance.

 

Avos is right - AJ27 valves are 101.5mm tall. Length from bottom of the valve to keepers groove is 89.5mm.
Now it will be exelent if someone can measure AJ41 valve dimensions. If not I'll measure them when I receive two pieces that I ordered before a week

Good news from this evening is that AJ33 exhaust manifolds will be almost direct fit.

Here AJ27 exhaust gasket/heatshield put on the head


Here is the same AJ27 gasket on AJ33 exhaust manifold


I'll match manifold port to gasket, so I can eliminate this pretty big edge on this transition.

As for the head, I'm quite satisfied with how it looks right from the factory. Quite good casting, very good design, no sharp edges bellow valve seats.

I'll try to smooth out casting imperfections, to polish ports, and I think maybe ita will be a goood idea to touch a little bit here


Also I'm biased on teories of knife sharp vs oval intake port deviders.
I don't know which one is better but maybe more oriented toward oval deseign.

 

Quattro I would knife edge the splitter of the port. Make it curve inwards like an Aj27- but much sharper- like a BMW S54 M3 engine. The Aj33 divider is a mess.


The AJ37 Aston Martin port is like a BMW M62 with the port divider much closer to the valves themselves- but this is done mainly to minimise port wall wetting for HC emissions. Nope- better to use a BMW M engine as a guide.

 

Quattro- apart from the ramp height differences I was talking about the actual cam profiles were identical.


Take a look at these specs covering various Jag engines





The AJ30 is the Lincoln engine as is the AJ35.MOP= Maximum opening point. All the meantherthile, dogmatic hot rod community use LSA or lobe separation angle and LCA of lobe centreline angle and they quote lift at 50 thou- but those old norms are pretty useless.


AP is affirmation prototype where as CP is conformation prototype- CP is closer to production. Notice how we had to make the durations for the Intake cams longer for AJ33 N/A at CP level compared AJ27 N/A- this was due to the bad ports for the larger engine capacity.


9 mm lift isn't that tame- for a given duration you can only lift so high. For 240 period 9 mm is good. The BMW M52 has only a 228 duration cam and much less lift. You can't compare the durations and lifts to an engine with fixed cam timing- variable cam timing engines optimise out at much shorter durations. Old fixed cam timing 4 valve engines like the BMW M88/3 had durations of 260, may be a bit less, but once you have variable cam phasing the optimum duration comes down by about 20 degrees. If the duration comes down then so does the peak lift because you can only lift so high- youre limited by the tappet diameter and duration.


The AJ37 Aston Martin V8 has a duration of 256 and a lift of 11.1 mm.

 

Again very nice info from you Count Iblis!


However I'm a little bit confused with all these data.
What is SP and WH in this table? I'm sure I measured 9mm lift on intake cam on my engine. From these data it will mean it is already 240 degree duration in this case.


I'm confused also by AJ28 designation - what is this?


Also while reading at this forum I noticed that in many cases it was suggested to use 4.2 head gaskets because they are MLS, but mine head gaskets was already MLS made by Goetze. Is there production AJ27 made with MLS gaskets? I'm 90% sure that this engine wasn't stripped before this secondary chain tensioner accident.


btw.. increasing lift to AM specs - 11.1mm won't result in valve/piston clearance issues on some setting of VVT?
2mm more lift is quite good advantage I think
In Audi world, I was changing turbo camshafts for NA ones, and this brings less than 1mm lift gain. But I must admit, that Jaguar head is much, much better looking than 5v VAG heads.


Cheers,
Christo

 

Head gaskets were MLS ones from MY 2001. Earlier ones were composite gaskets and they were too easy to burn.

 

So left head is almost ready for fitting back on the car.


First, as avos noted LR valves are longer than Jaguar valves - I don't know why there is a difference, but here it is:



Good news is that keepers groove is on the same height, so I can manage with this situation.


next task - open up exhaust ports to match gasket...
from this..

to this..



I focused more on sides, than top&bottom, because there is a big narrowing there.
As a whole, exhaust ports shape is awful to work there.
I tried to remove those "bumps" on the roof of the port





after that it is time for intake ports...






Now I'm thinking on re-profile stock cams - It is hard to find good set of cams and followers on good price, so I can experiment with them.
Locally I can send my cams to a workshop, to reproduce different cam profile on my cams (shortening base of the cam).
In this case I'm interested if the duration numbers from above are measured on 1mm lift or on 0.01.


Cheers,
Christo

 

<First, as avos noted LR valves are longer than Jaguar valves - I don't know why there is a difference, but here it is:

I believe that the reason that RR valve stems are longer is because of the different cam follower/bucket designs. Jaguar uses a bucket with adjutable shims on top. This requires shorter valves to retain the same spacing below the camshaft. The RR buckets are a one-piece design with a larger OD, and varying thicknesses.