Shrick cam with 1mm skim question

[Cypriotgeeza]

This is for the M30 gods on here I need a bit of advice.

Now for those of you that have followed my progress over the years you will know that I have given my head a "good skim" meaning I had 1mm skimmed off the face of the head.

Now I'm considering getting a Shrick cam and porting and polishing the head.

Would a shrick cam make the valves open so much that I could risk contact between valve and piston? or do they only open them for longer periods?

Any help would be appreciated!

[maggspower]

You can take all the advice off here you want.

The only way to know for sure is to remove the head, fit the cam and then take measurements of how close the piston to valve clearance is.

[Cypriotgeeza]

You can take all the advice off here you want.

The only way to know for sure is to remove the head, fit the cam and then take measurements of how close the piston to valve clearance is.

Of course, was just wondering if anyone had done it before..opinions etc..

I'm even after opinions of people who have shrick cams in standard M30 heads.. what degree of cam they have, what power gains they got...that kind of stuff!

[maggspower]

You can take all the advice off here you want.

The only way to know for sure is to remove the head, fit the cam and then take measurements of how close the piston to valve clearance is.

Of course, was just wondering if anyone had done it before..opinions etc..

I'm even after opinions of people who have shrick cams in standard M30 heads.. what degree of cam they have, that kind of stuff!

Yes I have done it

The schrick offering for the m30 is reasonably mild, they only do one, and I don't think it would hit. But I'm not a betting man, a new head gasket is much less grief than a new head gasket and repairing a load of valves.

VAC motorsport USA sell an adjustable cam sprocket, this will help you as a 1mm skim, will put your timing out anyway, and allow you to get the correct timing and enough clearance should your valves be too close.

The right way of doing it is to pocket the pistons a little to clear the valves but this requires even more disassembly. Although this will lower the compression, which is a negative with an uprated cam, you want as much static compression as you can.

You want to be looking at a minimum of 1.5mm of clearance between the valve and piston by the way.

[Cypriotgeeza]

Yes I have done it

The schrick offering for the m30 is reasonably mild, and I don't think it would hit. But I'm not a betting man, a new head gasket is much less grief than a new head gasket and repairing a load of valves.

VAC motorsport USA sell an adjustable cam sprocket, this will help you as a 1mm skim, will put your timing out anyway, and allow you to get the correct timing and enough clearance should your valves be too close.

The right way of doing it is to pocket the pistons a little to clear the valves but this requires even more disassembly. Although this will lower the compression, which is a negative with an uprated cam, you want as much static compression as you can.

You want to be looking at a minimum of 1.5mm of clearance between the valve and piston by the way.

Now this is more like it

Yea I'm actually considering either going down the turbo or supercharger route so a major disassembly may be on the cards..

which degree cam did you have? I've heard there are 300 degree but most I've found is 284 degrees..

I will look into this adjustable cam sprocket..could really help out in the future..

[maggspower]

Well you have some decisions to make then. Forced induction you will need to lower the compression not make it more.

You already have the best cam for forced induction, the standard one. Uprated cams on forced induction are crap, the overlap that makes them perform in N/A tune works against the turbo, it shoots a load of the blown turbo air out the exhaust along with fuel. You will make less over all power.

An engine needs to be built with its purpose in mind, you cant build a great N/A engine then at later date make it turbo, to get the best out of it either build it N/A or turbo, not both.

The £400 the cam would cost, would be almost the price of a Holset turbo. No prizes for guessing which will make the most power

Although the turbo is a fraction of the cost of an entire F/I build.

[Cypriotgeeza]

Well you have some decisions to make then. Forced induction you will need to lower the compression not make it more.

You already have the best cam for forced induction, the standard one. Uprated cams on forced induction are crap, the overlap that makes them perform in N/A tune works against the turbo, it shoots a load of the blown turbo air out the exhaust along with fuel. You will make less over all power.

An engine needs to be built with its purpose in mind, you cant build a great N/A engine then at later date make it turbo, to get the best out of it either build it N/A or turbo, not both.

The £400 the cam would cost, would be almost the price of a Holset turbo. No prizes for guessing which will make the most power

Although the turbo is a fraction of the cost of an entire F/I build.

Very true my friend..Winters coming and I'm considering what project I'm going to embark on with the M30 before next summer..

Your right i have alot of thinking to do

[Rav335uk]

Gareth did a 1mm skim with standard H/G iirc.
Look for his thread in the M30 section.

And don't go down the supercharger route it's crap (I'm going that route,lol)

[Cypriotgeeza]

Gareth did a 1mm skim with standard H/G iirc.
Look for his thread in the M30 section.

And don't go down the supercharger route it's crap (I'm going that route,lol)

Yea my head is skimmed 1mm Rav man!

Yea supercharging is very rare and you have power on tap through out the whole rev range but my god is it expensive!

I looked into doing it but compared to charging it turbo'n it is a bargain! lol

I look forward to seeing your progress one day! (if you ever update your project thread )

[Rav335uk]

I will once i've done what I need to do regarding the house renovations, then i'll have time with out interference.

[Cypriotgeeza]

I will once i've done what I need to do regarding the house renovations, then i'll have time with out interference.

[ImysE30]

Turbo it, you know you want to

[Bristol_Jer]

I've got the Schrick cam in mine, with a head skim (although I can't remember how much exactly) all done by Byron I also bought the adjustable cam pulley from VAC, but not fitted it yet, will get it on and get the car rolling roaded over the winter.

It's quite a mild cam as Byron said, the idle is still pretty smooth, you lose a bit of bottom end grunt and once it gets to around 3500-4000 rpm it takes off and puts a nice grin on your face. I looked into turbocharging but thought I just wanted to keep it simple and hopefully reliable (so far so good!) so kept N/A. With the 3.73 diff it's plenty quick enough for now on trackdays which is what it's built for, although I have most of the bits now to fit triple Jenvey TB's and Megasquirt