Valve to piston clearance question

[joat09]

Is there a way to check the valve to piston clearance with clay without having to time the engine?

6-bolt
Mahle 9:1 Pistons
Manley rods
HKS 272 cams
Revised lifter
oem rockers
Oem spec valves
Block has be decked .5mm possibly .25mm(.010")
No material has been removed from head
Tri-metal HG

 

[BogusSVO]

With the block decked .5mm or .020 the piston is probly sticking out the top of the block by .010-.015, Most blocks I have checked the piston is in the hole .006-.010

But to anwser your question about claying the pistons to check valve clearance, no you will have to set the timing belt up to get the measurements you need.

 

[joat09]

With the block decked .5mm or .020 the piston is probly sticking out the top of the block by .010-.015, Most blocks I have checked the piston is in the hole .006-.010

But to anwser your question about claying the pistons to check valve clearance, no you will have to set the timing belt up to get the measurements you need.

The piston is in the hole .010-.015 like you said. Perhaps only .10 was taken off. The piston is not out the of the top of the block for sure. It is near flush almost.

I set the pistons to TDC and cycled the valves. They touched of course. I didn't put 2 and 2 together about it being an interference engine.

 

[YZFR1]

I have a question that i've been pondering on that has to do with Piston to Valve clearance.

The correct way to do it is to Dry Assemble the block, however, wouldn't that scuff up the bearings and such?? Is it OK to use a light film of oil or assembly lubricant when doing this procedure and still get accurate results?

 

[viperlp01]

Haha ya its just a phrase... You use lubrication. What is your lift/duration and advertised compression ratio.

 

[YZFR1]

^Not sure if you are asking me or the OP but my lift/duration are 11.2/274 & 11/274 with advertised compression of 8.8:1. If i remember right the piston sits about .018" in the bore the last time i checked it.

 

[viperlp01]

Ya I was asking the OP but if the piston is sticking in the hole .018 I would say your good with a .039 headgasket and lift 11.5mm or lower.

 

[YZFR1]

Ok thanks. I hope OP doesn't mind if i ask another question on this subject

Is it OK to reuse the headgasket after torquing it down to measure PTV, being it graphite or MLS? Or do people use up a headgasket just for this? Just another concern i've had about this.

 

[viperlp01]

You don't torque it down. Just snug the bolts up or don't even use a head gasket and calculate your numbers off the known head gasket thickness.

 

[BogusSVO]

Or use an old HG, or an ITM or an Evergreen HG.

I have 3 or 4 HG from ebay/Evergreen gasket kits That are used for "shop" work..

 

[joat09]

I'm not sure on the lift, I still need to get a cam card.

delta camshaft HKS 272 regrinds
pistons are 9:1

Evergreen gaskets are junk, I tried HG out on my honda for a cheap fix. Hydrolocked... Used a Felpro and it ran really good.

 

[YZFR1]

When checking Piston to Valve clearance is it absolutely necessary to use solid lifters or is it possible to get away with regular lifters and stll get a decent reading or atleast an idea where you stand?

Also, when doing the procedure what is the best way to figure out how far one can adjust cam gears without any interference?

My take on it would be to install the head without the headgasket, then install the timing belt. Then adjust cam gears until you slightly touch the pistons, note the settings on both cam gears when this happens. The headgasket itself would serve as a buffer when everything is intalled like normal. And you would have an idea of how far roughly you can go on each cam gear. Does that make sence?

 

[BogusSVO]

There is a thread on the board, telling how to change an old hyd. HLA into a test solid HLA using washers.

You can find the specs for the HKS cams in this thread.

http://www.dsmtuners.com/forums/cyl...5135-camshaft-identification-information.html

I doubt you are close to PTV issues, the HKS 272 Intake has the most lift at 10.3mm or .406 lift

 

[YZFR1]

I have GSC s2's with an 11.2 intake lift and 11 exhaust but i guess they are not that aggressive also.

I already have washers to adjust the lifters and a couple spare lifters, the only thing is from my understanding it is almost impossible to adjust them for 0 lash or even a .001" preload. I tried before and it is not easy and takes a LOT of time and patience and even than you never know for sure of how off you are.

What about my cam gear adjustment theory, how does that sound? Thank you

 

[BogusSVO]

No, you use a junk HLA, pull it apart, keep the body and nose, you fill the body of the HLA with washers then put the nose back on. This makes a solid HLA for checking specs, not to be run!!

11.2mm = .441

 

[YZFR1]

I have a couple of junk HLA's and various size washers to drop in there. I guess the main question is how would i know how many washers to put in there to have zero lash? Or would just having a solid lifter not set to zero lash would be enough?

My understanding of this was we needed zero lash to get accurate results :?:

 

[BogusSVO]

You will end up pulling it apart and changing the washers in it untill you achieve 0 lash

 

[YZFR1]

I have tried doing it that way before and i'll be honest i didn't have much confidence in the accuracy of it. However, i was lucky enough yesterday to find a couple used solid lifters

 

[joat09]

Thanks Bogus

Can I get away with using 4 solid lifters or should i really use 16?

I'm pretty confident the clearance with be fine, I just feel i should check clearance with this being my first rebuild. I want to make sure everything checks out.

Im also going to be degreeing the cams in, ive never done either on an interferance engine before.

 

[954g63gst]

My understanding of this was we needed zero lash to get accurate results :?:

That is true yzfr1. Solid lifters is a good way to go about adjusting to 0 lash. Four solid lifters in each corner will be good enough to take accurate measurements. Putting washers in the HLA works also but can be fussy getting to 0 lash.