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Safe maximum RPM on whiteblock 6?

Aren't the hydraulic lifters more of a concern at sustained higher rpm? Kenny - did you switch to solid lifters on yours?

I run my T5 to 8500+, but I have solid lifters. I also switched to the longer rod (147mm)/short skirt piston setup.

Has anyone found they were running into valve control issues of any kind while retaining the stock hydraulic followers? One of the main advantages of using the 4VPC cylinder heads at high rpm should be the reduced possibility of valve float with individual components of much lower mass, even with hydraulic followers?

Does the T5 normally feature solid followers or are these aftermarket items? The combination of a longer rod and shorter/ lighter piston is always a good move on a high speed motor, but running to over 8500 rpm on one of these engines is still very impressive....that surely must be with aftermarket rods?
 
I never measured mine when I had them out, are these lifters shared with a VW or BMW motor by chance? I can't imagine them being all that different.....
 
T5 and T6 have solid lifters after around MY2000. Cam base circle is different and there are some other major changes though.

Lash is measured via access ports in the head casting that are blocked by removable plugs.

Lash is set by ordering the lifters you need from Volvo.
 
T5 and T6 have solid lifters after around MY2000. Cam base circle is different and there are some other major changes though.

Lash is measured via access ports in the head casting that are blocked by removable plugs.

Lash is set by ordering the lifters you need from Volvo.


Seriously? No shims or anything? That has to be expensive.
 
T5 and T6 have solid lifters after around MY2000. Cam base circle is different and there are some other major changes though.

Lash is measured via access ports in the head casting that are blocked by removable plugs.

Lash is set by ordering the lifters you need from Volvo.

That is interesting, and given the cost and lack of choice for alternative camshafts on these engines, could also open up one-off regrind possibilities.

Are the later T5/ T6 base circles diameters smaller than on the hydraulic cams or the other way around?

Lack of shim adjustment in the lifter/ follower design is a bit of a pain though... true it probably makes the whole arrangement lighter and safer to rev even higher with no shims to come adrift, but with 24 to get that will all likely need their clearance changed by the same amount at the same time that does seem like an unnecessary extra expense.

Actual clearance adjustments in normal use are only going to be necessary few and far between, but in harder use with frequent tear downs and part swapping this could change.

While never quite reaching the same level of direct action, at higher rpm reduced lifter bleed-down time should bring a hydraulic lifters performance very close to that of a solid lifter albiet also with a valvetrain weight penalty. On balance I think I'd probably just prefer to stick with the hydraulic parts unless planning to run to a more extreme rpm limit.

They are highly unlikely to be the same component used in any other make of engine....and it might even be making too big an assumption to think that the T5/T6 solid lifters will be a direct fit in the 'hydraulic' whiteblock head......are their diameters etc the same and therefore potentially compatible?
 
The specific size old style shims used in redblocks were also used by VW, Fiat, etc. I would be surprised if the solid lifter shim/bucket is not used by other manufacturers. However, if you are in the situation you describe where you would be tearing down on a regular basis, then just grind the valve stem to set lash instead of buying caps.

I don't recall which style has the larger base circle, I think it's the solid, but wouldn't be too hard to confirm that.

You could convert an early head by changing the valve guides to suit the thinner stem valves, then use the later buckets. Pretty sure the head casting did not change due to the valve/lifter design change.
 
The specific size old style shims used in redblocks were also used by VW, Fiat, etc. I would be surprised if the solid lifter shim/bucket is not used by other manufacturers. However, if you are in the situation you describe where you would be tearing down on a regular basis, then just grind the valve stem to set lash instead of buying caps.

I don't recall which style has the larger base circle, I think it's the solid, but wouldn't be too hard to confirm that.

You could convert an early head by changing the valve guides to suit the thinner stem valves, then use the later buckets. Pretty sure the head casting did not change due to the valve/lifter design change.

You'd need to machine access ports in order to be able to measure the lash. Some heads had bosses for that but I'm not sure all of them did.

It's way more work than starting with a solid lifter equipped head, that's for sure.

There's more different with the cams than just base circle - the VVT requires different journal arrangement, etc. You can't quite mix'n match that easily, unfortunately.
 
Mmm... what MIGHT be of interest would be use of a set of solid lifters from another manufacturer that DID incorporate bucket and shim type valve clearance adjustment. Some component spec checking in the EP catalogues might be of use here?

I think the normal swap-for-clearance-adjustment T5/ T6 lifters would be perfectly fine for normal use, but less so for a regularly worked on competition type motor. I wouldn't want to get into altering valve lengths for adjustment (unless that was purely to allow for use a bigger cam base circle diameter) for a few reasons, not least that it would be a one-time adjustment and in use the clearances are always going to get LARGER with use.
The valve guides could either be changed or fitted with something like K-Line inserts to allow use of thinner stem valves while at the same time removing any wear in them.

In honesty, the beauty of using one of these motors at lower boost levels and rpm limits to me is that the vast majority of stock components can be retained to keep costs down while still giving good results and reliability If something then does fail seroiusly it isn't soul destroying or bank breaking, and most service parts are common, readily available and inexpensive. If I wanted to be throwing large sums of money at an engine in the pursuit of a lot more power I would probably have started off somewhere else.


This is exactly the kind of thing I'm trying to avoid by using a whiteblock motor in the first place....




For what I want then, a modified stock whiteblock head will get the job done. Even the obvious shortfalls in the block and bottom end design can be disregarded at slightly lower outputs and levels of heat, pressure and reciprocating component loading. I am a little surprised at how fast these motors are being revved without issue in fairly stock form by some people though.... all to the good.

It is a shame that the T6 cam (if it does have a larger base circle diameter) isn't quite so easy to drop into a normal whiteblock head. Reprofiling a pair would have been much cheaper and have given many more profile options than just buying one from someone like Cat Cams.

My usual cam grinders charge by the lobe, and while a 24V whiteblock would have been close to three times the price of reprofiling a redblock cam for example, it would still have been a fraction of the cost of buying new cams.

It would be interesting to see a normal whiteblock and T5/T6 can side by side for a direct dimensional comparison of their bearing surfaces..... and to see how much 'meat' is really in the T6 lobes.


I would have loved to have built a high-output N/A version of one of these engines if only it were more practical.
 
Yes, at those sort of RPMs the lifters don't have much time for leaking down.... but they don't have much time for oil pressure to refill them again either!

For short term use of very mild levels of forced induction (used more as an aid to volumetric efficiency) I'm thinking of using bigger injectors and an adjustable fuel pressure regulator. Doing this would be of even greater benefit by the sound of things if the motor could be run to about 7000rpm as well, but without going to an aftermarket management system just at this time.

Can the stock Motronic unit be modified to permit this fairly easily and if so what is required to do it? Maybe a chip change is available that would help cover the minor spec changes I want to make for the time being?
 
Thanks for those links, on the face of it this would appear to be perfectly possible with the 4.4 Motronic....... at least for those people who know what they are doing in this way. I've been looking into this, and I'm going to research it a bit further.

Unfortunately I'm really a mechanical sort of guy, and with electronics and software codes in particular I'm a bit of a fish out of water and don't really follow too much of it.

A search in the second link threw up some really interesting threads, but whether that would actually lead anywhere for me is another question.


I can easily see this side of things being much more involved than the fabrication and installation of the new hardware parts!
 
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