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Discussion Starter #1
as opposed to the normal ones, actually what is a lifter anyway? And what is a lash cap?

as allways thanks to anyone that can enlighten me.
 

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Jahangeer said:
as opposed to the normal ones, actually what is a lifter anyway? And what is a lash cap?

as allways thanks to anyone that can enlighten me.
1 Viagra?
2 Some sort of sado masochistic paraphenalia?
Sorry couldnt resist it :hihi:
 

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Lifters are the bit that go between the cam lobes and the top of the valve.

Solid ones are better than hydraulic for performance reasons - they perform more accurately.

Hydraulic are maintenance free though cos they're filled with oil - quieter too. Solid ones need shims adjusting at regular intervals to ensure maximum performance.

Not sure on what a lash cap is, unless it's just different terminology for shim?
 

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whats the right interval to adjust shims ?
 

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Discussion Starter #5
Rob Plummer said:
Lifters are the bit that go between the cam lobes and the top of the valve.

Solid ones are better than hydraulic for performance reasons - they perform more accurately.

Hydraulic are maintenance free though cos they're filled with oil - quieter too. Solid ones need shims adjusting at regular intervals to ensure maximum performance.

Not sure on what a lash cap is, unless it's just different terminology for shim?
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thanks Rob. Now I know ;)
 

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Thank's I 'll chack then ,... I'm pretty shure that it has never been done to my engine. I'm planing changing cam sprockets, and I think I'll adjust shims at the same time.

Eduardo
 

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MBrasil said:
Thank's I 'll chack then ,... I'm pretty shure that it has never been done to my engine. I'm planing changing cam sprockets, and I think I'll adjust shims at the same time.

Eduardo

Get them done! It's not just the performance, it's wear as well. You could be wearing out the lifters, cam lobes and maybe other stuff too!
 

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Lifters follow cam solid lifters give more accurate movement as they are fixed, however require routine adjustment for wear and tear. This a an inspection 2 item. Hydraulic lifters were introduced to eliminate the need for this maintence and also run quieter as the oil filled lifter will act like a shock absorber when off the lobe. The mechanical (solid) lifter will reduce valve float as higher compression springs can be utilized there by increasing the ability to attain higher RPM. Ideally you would like mechanical followers to open and close valves as were introduced by Alfa way back in the 1900's.

Valve lash is the clearence in the valve train. Lash caps are used to set that clearence.
 

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Discussion Starter #11
ah ok, "lash caps " are shims then. thanks unessential.
 

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Discussion Starter #12
unesential said:
Lifters follow cam solid lifters give more accurate movement as they are fixed, however require routine adjustment for wear and tear. This a an inspection 2 item. Hydraulic lifters were introduced to eliminate the need for this maintence and also run quieter as the oil filled lifter will act like a shock absorber when off the lobe. The mechanical (solid) lifter will reduce valve float as higher compression springs can be utilized there by increasing the ability to attain higher RPM. Ideally you would like mechanical followers to open and close valves as were introduced by Alfa way back in the 1900's.

Valve lash is the clearence in the valve train. Lash caps are used to set that clearence.
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but could you get a more responsive engine if you used forged lightweight pistons?
 

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Discussion Starter #13
how about some of the stuff on this - dont understand some of it - what does it mean by "unshrouding of valves"

And resurfacing the face - isn't that dangerous - I thought the tolerances were too small on the S38?

Whats a "valve guide"?


------------------------
Cylinder Head
--------------------------------------------------------------------------
VAC Stage 1 Performance Cylinder Heads
VAC's Stage 1 Performance Cylinder Heads are our best seller out of all the Reconditioned Cylinder Head options we offer. They offer more performance for at only a slightly higher price. Best of all, our Stage 1 heads are still Stock class legal.
Our Stage One Cylinder Heads feature the following:
Full Radius Valve Job using Serdi Equipment
New Valve Guides
Reconditioned or New Valves
Balanced and Blueprinted Valves
Balanced Springs
Resurfaced Face
Unshrouding of Valves
Flow Bench Tested
VAC High Performance or BMW Motorsport Valve Springs Recommended
Core Charge Required
 

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Jahangeer said:
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but could you get a more responsive engine if you used forged lightweight pistons?
Not sure - my understanding is that forged pistons are stronger and lightweight pistons (short skirt) reduce friction losses and enable higher revs........


Valve guides are the bits the valves run in - like a tubular insert into the head. Not sure about the other stuff. Probably BMW terminology.
 

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What type of lifters are in the 3.8 engine, is it the fixed lifters with simmies.
cheers


Rob Plummer said:
Not sure - my understanding is that forged pistons are stronger and lightweight pistons (short skirt) reduce friction losses and enable higher revs........


Valve guides are the bits the valves run in - like a tubular insert into the head. Not sure about the other stuff. Probably BMW terminology.
 

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Lightweight pistons reduce inertia needed to move piston thereby increasing response to throttle due less internal power loss. They ussually are weaker and used in a non race setup. This is not the quite the same as difference in valve train.

Valve guides are exactly what the name states. they are bushing in the head that the valve stem passes through.
Unshrouding is the removal of material not deemed needed around the valve port. sometimes refered to as porting.
Refacing with multi angle grinds can aide airflow, not sure if I would do it with my beast. Maybe as last resort during a head rebuild. Reseating should be done carefully.

With regaurds to to head overhaul those items are typical. Other than matching springs and porting.
 

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shuggy47 said:
What type of lifters are in the 3.8 engine, is it the fixed lifters with simmies.
cheers
Defo solid lifters in the 3.8, just had mine checked by BMW for £200 ouch. I used to own a Peugeot where you could adjust them by a screw and locknut, much easier than all the shimming. On that note, how hard is it to shim them on the 3.8 M5?:typing:
 

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Discussion Starter #18
madm5 said:
Defo solid lifters in the 3.8, just had mine checked by BMW for £200 ouch. I used to own a Peugeot where you could adjust them by a screw and locknut, much easier than all the shimming. On that note, how hard is it to shim them on the 3.8 M5?:typing:
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Apparently it is not that hard - you need to buy a specific tool - I have been told - sorry I cannot tell you what it is. My freind does his own valve clearance check and adjustments - takes max a few hours for him to do it.
 

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BMw tool 11-3-170 or equal is needed toto compress spring for accesstoadjusting disc. an air compressor comes in handy to blow out disc that needs replacing with different size disk.
 
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