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Timing question
#50
ok,
you forget? any country on earth can order a rebuilt head from USA? (with only a tiny tiny shave, .001" or so, they will reject your head, for any CORE value, here state side, its consider just scrap aluminum. sorry.
so it not 3rd world, issue
it's cash only.
or down time?

All engines with a quench area in the piston to combustion chamber, is tuned for fast flame fronts and low ping
it works so good the G16 will not ping, ever. (needs no knock sensors with dynamic retard)
when its shaved, 2 things happen, that quench area is wrecked, and CR GOES TO HELL too.
The 3rd effect is spark timing tables (or distr/mech/vac) advance settings are now all useless, (so back off advance)_

the belt is cut for stock head, the service manual lists the max milling cut (shave) spec.
belt will cause the belt to be too long (cog pitch is fixed)
forcing the belt installer to run cam timing wrong. + 1 cog or -1cog.(like you)

fixes,
1:a rebuilt head (from real head maker, that follows the rules)
2: run 2 head gaskets
3: run custom advancing ,lots and lots of tuning, like all dyno tunes engines are done. (for same reasons)
4: upgrade to EFI and tune the spark tables, and ditch the mech, distrib, and vacuum magic.(or go MPI)
5: run a G16 variable cam gear. can help. off swift sites. http://thumbs.ebaystatic.com/images/g/ad...s-l225.jpg
6: run AV gas, 100 octane fuel $$$$, or run more E85? And tune to that?

I wonder , with this SHAVE is the engine still free running? we check that with the clay trick. on top of the piston.
if the hand turned cam , crank a TDC 0, held there,
tune cam, hits?
no, we do the clay test,to be sure its not too close. exhaust stroke,
if the cam is such and the shave is extreme the piston might say get to near .001" of the valve.
so later, when engine fully hot and driving fast,it hits, all race engine makers do that test, a last step before final assembly. (no need stock engine)


if I saw gross shaving it be all over that in a heart beat, head in hand.
would..(and having no other choices.)
on other engines they have steal head gasket shaped, shims, to get CR where they want it
most real turbo mod.'ers do that, to have low CR to start that turbo. (so does Honda) its called the safe place,
the ECU has safe place to go, when BAD happens. (like LEAN happens underboost)
my point here,is they sell those shims.
problem is you are like the only 1 of 10 G16b racers... so parts hard to find. Its not a toyoto/nissan/Honda)


off the main head sight(see that thing about CAM bores?)
Aluminum heads can be straightened by countershimming the head on a heavy steel plate (place shims under either end of the head to offset the amount of distortion), clamping it down, then heating it in an oven to about 425° F for several hours, then letting it slow cool. The goal is to get the cam bores straight. Once they are in alignment, chances are the face of the head will be reasonably flat, too, and require minimal machining to refinish the surface.

Another method for straightening aluminum heads is to use a torch to head the top of the head, starting in the center and working towards the ends. The trick here is to keep the head temperature under 500° F to prevent softening the head too much.

here is a guy I think in LA. with wall to wall machine shops there. that can dewarp it with heat , saving the CAM bearings
https://www.youtube.com/watch?v=HyKN52HD6RU

some own forgot to tell him, hey fella both sides warp, cam bearings and all.
fun to watch , and LOL
http://www.fixkick.com
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Messages In This Thread
Timing question - by Swiftdoog - 05-29-2016, 09:35 AM
RE: Timing question - by Swiftdoog - 05-29-2016, 12:16 PM
RE: Timing question - by Swiftdoog - 05-30-2016, 12:07 AM
RE: Timing question - by fixkick - 05-30-2016, 04:45 AM
RE: Timing question - by Swiftdoog - 05-30-2016, 08:27 AM
RE: Timing question - by Swiftdoog - 05-30-2016, 10:12 AM
RE: Timing question - by fixkick - 05-30-2016, 10:51 AM
RE: Timing question - by Swiftdoog - 05-30-2016, 12:29 PM
RE: Timing question - by fixkick - 05-30-2016, 11:51 PM
RE: Timing question - by Swiftdoog - 05-31-2016, 03:26 AM
RE: Timing question - by fixkick - 05-31-2016, 05:58 AM
RE: Timing question - by Swiftdoog - 06-04-2016, 02:44 PM
RE: Timing question - by fixkick - 06-04-2016, 07:40 PM
RE: Timing question - by Swiftdoog - 06-04-2016, 09:18 PM
RE: Timing question - by fixkick - 06-04-2016, 10:18 PM
RE: Timing question - by Swiftdoog - 06-05-2016, 08:20 PM
RE: Timing question - by fixkick - 06-05-2016, 11:36 PM
RE: Timing question - by fixkick - 06-06-2016, 12:45 AM
RE: Timing question - by Swiftdoog - 06-06-2016, 08:06 AM
RE: Timing question - by fixkick - 06-06-2016, 08:35 AM
RE: Timing question - by Swiftdoog - 06-06-2016, 08:45 AM
RE: Timing question - by fixkick - 06-06-2016, 09:33 AM
RE: Timing question - by Swiftdoog - 06-10-2016, 03:21 AM
RE: Timing question - by fixkick - 06-10-2016, 06:17 AM
RE: Timing question - by Swiftdoog - 07-22-2016, 08:12 PM
RE: Timing question - by fixkick - 07-22-2016, 10:39 PM
RE: Timing question - by fixkick - 07-22-2016, 11:00 PM
RE: Timing question - by fixkick - 07-22-2016, 11:09 PM
RE: Timing question - by Swiftdoog - 07-22-2016, 11:30 PM
RE: Timing question - by fixkick - 07-23-2016, 12:14 AM
RE: Timing question - by fixkick - 07-23-2016, 12:20 AM
RE: Timing question - by fixkick - 07-23-2016, 12:22 AM
RE: Timing question - by Swiftdoog - 07-23-2016, 12:25 AM
RE: Timing question - by fixkick - 07-23-2016, 12:35 AM
RE: Timing question - by fixkick - 07-23-2016, 12:43 AM
RE: Timing question - by Swiftdoog - 02-06-2017, 07:20 AM
RE: Timing question - by Swiftdoog - 02-06-2017, 10:17 AM
RE: Timing question - by fixkick - 02-06-2017, 10:24 AM
RE: Timing question - by fixkick - 02-06-2017, 10:27 AM
RE: Timing question - by fixkick - 02-06-2017, 10:47 AM
RE: Timing question - by fixkick - 02-06-2017, 10:54 AM
RE: Timing question - by fixkick - 02-06-2017, 10:54 AM
RE: Timing question - by Swiftdoog - 02-07-2017, 01:48 AM
RE: Timing question - by fixkick - 02-07-2017, 03:09 AM
RE: Timing question - by fixkick - 02-07-2017, 03:20 AM
RE: Timing question - by fixkick - 02-07-2017, 03:29 AM
RE: Timing question - by fixkick - 02-07-2017, 03:38 AM
RE: Timing question - by fixkick - 02-07-2017, 03:39 AM
RE: Timing question - by Swiftdoog - 02-07-2017, 09:42 PM
RE: Timing question - by fixkick - 02-07-2017, 10:39 PM
RE: Timing question - by fixkick - 02-07-2017, 11:59 PM
RE: Timing question - by Swiftdoog - 02-08-2017, 12:58 AM
RE: Timing question - by fixkick - 02-08-2017, 02:58 AM
RE: Timing question - by fixkick - 02-17-2017, 12:09 AM

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