I have a block that has the pistons .016 out of the bore and a head that has been milled .015 . I know my true timing is thrown off and I was wondering if anybody knows how to exactly dial in the timing using Adj. cam gears?

 

You will have to degree your cam in order to do this properly. MINIMUM .045 intake and .055 exhaust piston to valve clearance....i think u need to give a machine shop a call. I dont believe anyone will have a pre known cam gear offset for you. If you need adjustable cam gears go to my website in the sig and click the link for speed theory. He has a great deal on full-race cam gears but please take my advice and contact someone who can dial in ur appropriate valve timing.

 

I already have cam gears, but thanks for the try.

Do you think my Piston to Valve Clearance is dangerous right now? I am also running .5mm oversize valves. I was thinking about setting the cam gears advanced about +5 and locking the motor into vtec and rotating the crank to see if I have contact. I am running dished Wiesco's right now with a cometic .065" gasket. I wanted to clay the motor when I built it but the machine shop was not interested in doing it.

 

bump

 

Although you may or may not be succesful with this...I dont think anyone on here is going to say that this is safe....even if you rotated the crank to check for interference you still are unsure of proper clearances. The motor should have definately been clayed.

 

I am fully aware that this motor needed to be clayed, there is nothing I can do about it now, I am not pulling the motor and stripping it down. My main motive for checking for contact was that if everything stops rotating at +8 I know I can safely advance to lets say +3 which is all I need to do, I am only looking to dial intiming, not looking for a performance gain.

 

I bought a cam degreeing kit for $99 off fo ebay. I had to modify it some to work with a B-series head, but it wasn't too hard. Be sure to lock VTEC when you do it, I just pulled my rockers and swapped them around to take care of that. Then you can get the cams in the right place and check your piston-valve clearance.

P.S. - If you are using Honda cams, then you can just use the alignment dowel holes and you don't need to degree tham.

 

When you start taking material off, the thing needs degreed period. That means you need the degree wheel, a dial indicator, and the spec sheet (or specs) of the stock cam.

The deal with the claying, just because it rotates now without interference doesn't mean you won't have contact at high rpm. There is a degree of rod stretch and valve heat expansion you have to consider. Usually you don't run a piston crown any closer than .040 to the head for that reason.

Good luck....and do it right and have the piece of mind as a result.

 

Well the other two posts baisically said it for me...I am not trying to give you a performance gain...I am trying to tell you how to make sure you dont damage something. When i said "dial in" your cam timing I meant it as the right way to ensure proper clearances...as RC000E also stated, even though your valves may clear the piston...you dont know by how much they are clearing...and there is a minimum spec. for a reason...as RC000E also stated. At this point its either tear the motor down now and ENSURE clearances...or tear the motor down later and ensure clearances with a whole bunch of replacement parts for the things that broke.

 

Let me ask this, cant there be a mathematic way to determine where I am at? I know how much has been milled, I know the legnth of my rods and stroke of my crank, I know what cams I have etc.

or

How crutial is it that I be at exact timing, cant i just have the tuner leave it a point on the light side and call it a day w/o touching the cam gears at all? I have already run this motor to 9500 rpm w/o any problems, car is running full Ferrea valvetrain. The motor runs now so its not like I am gonna fire it up and bend all my valves.

 

Exact timing is actually pretty important, a difference of a few degrees can make a big change in how your motor performs. The problem is that the cams don't necessarily have a zero degree reference on them, so you have to use the specs of the cams, do the math, and measure them. Honda cams (and other cams made from the same blanks) have an alignment dowel hole that lets you determine where zero degrees is using the matching alignment hole on the cam holders.

If your cams have alignment holes, then the process takes a few minutes. Set the motor to 0 by the crank pulley indicator, loosen the cam gears, turn the cams until the alignment dowel goes through the cam holders and cams, then tighten the bolts on the cam gears.

If they don't have holes, like mine don't, then you need to degree them to figure out where they should be. Degreeing cams isn't that hard, and doesn't require a lot of money or dissasembling your motor, I don't see why you wouldn't just degree them and know for sure where your cams are at?

 

There might be...but that is up to your tuner. If you trust doing it that way and the motor runs now..then u may be fine. It will be up to ur tuner to decide if they want to do that.