milled the head .030

gsxr1216 · Feb 6, 2006

I have an 02 that is stock internally, I milled the head .030. What do you think this raised the compression to 12.5 to 1?

Stock is 12 to 1.

Yes it has cam sprockets so I set cam timing, 105 105.

APE JAY · Feb 6, 2006

Be careful of piston to valve clearances. When you mill the head, you are moving the valves out from center in relationship to the pistons. This can cause the valves to touch the backside of the valve pockets.

Jay

gsxr1216 · Feb 6, 2006

thanks for the info i'll check that

Tim Radley · Feb 7, 2006

30 thou off head!!! Oops, me thinks that will go bang. 20 thou is getting tight. Oh dear. Did it turn over ok on with the cams degreed up? Definately measure clearances.

gsxr1216 · Feb 7, 2006

can you give me minimum clearances for each side

thanks

GIXXER THE KID · Feb 7, 2006

I think it will be ok...He has stock cams in there. and he has them degreed to higher centerline numbers. But I always check PTV clearensse.

BallisticParts · Feb 7, 2006

Eeeeek

What Jay said.....There is more to this than just wacking stuff off the head.

Remeasure everything!

jeffw · Feb 7, 2006

Eeeeek

2nd that...

gsxr1216 · Feb 7, 2006

Ok now you guy's have me worried, the gasket is .027 thick, the pistons are .006 from the top of the deck when tdc. I didn't think .030 was a lot, they have a ton of clearance when stock. I've moddified a couple of other motors with 13.5 je's and web cam's and it wasn't that tight then either.

I know you going to say were talking about ptv clearance, and i'm gonna check that. I've only ran the motor once, so no damage. Can you tell what my minimum clearances should be.

thanks guys

JetSpeedz · Feb 7, 2006

if your worried just change the gasket.. but you should be ok with .03

gsxr1216 · Feb 7, 2006

GIXXER THE KID · Feb 8, 2006

min. PTV is .050 on the intake and .070 on the exhaust... Put some good valve springs in there too.

Flip 2 · Feb 8, 2006

I've got a .030 thick Cometic gasket, stock bore.
Cometic offers them at 36 and thicker, also.
.040 intake 10 deg ATDC
.075(maybe 70) ex 10 deg BTDC
KWS has a tool you can use (carefully) to move the tappet

You can assemble with your old gasket to check clearances and decide if you need a thicker gasket. $40- for mine (stilll in plastic)
<If you have the vales out still, you only need #1s on both sides in to measure.>

Take a look at your intake seats. Make sure (with Prussian Blue) you still have a good seal there. You may have cut some of the intake seat away.

Keep you busy for a day ;-)

gsxr1216 · Feb 8, 2006

It has 750 valve springs, it did not cut into the valve seats the machinest made 4 passes to check that. It was very close to the intake seats though.

thanks for the info i'll check ptv

Tim Radley · Feb 9, 2006

Don't forget to check pocket clearance as well and also make sure the bore is not too close to the valves.

milled the head .030

gsxr1216

APE JAY

gsxr1216

Tim Radley

gsxr1216

GIXXER THE KID

BallisticParts

jeffw

gsxr1216

JetSpeedz

gsxr1216

GIXXER THE KID

Flip 2

gsxr1216

Tim Radley

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