Thread: A few timing questions

Hey guys

I am in the process of timing my engine and I am running into a few different issues. I have a few questions and hopefully someone with some experience can chime in.

Just to give you guys a bit of back round information the on the engine it has aftermarket pistons, rods, and cam gears. The engine its self has had the head and block decked an unknown amount (machine shop conveniently forgot to record that data) and is using a vet metal head gasket.

Everything in this thread as of right now has to do with the low cam lobes (not in VVL).


Issue #1 (Solved)

The pistons TDC is not matching the crank pulley's mark.

When I set the piston to true top dead center (using an extension and dial indicator gauge) the crank pulley reads 23*

When I set the crank pulley to 0* (TDC) the actual piston is still going up on the compression stroke.

When I set the crank sprocket to TDC (matching the keyway to the line on the block) the piston is still going up on the compression stroke.

Question #1 (Solved)

Should I be setting the engine up from the crank pulleys TDC or the pistons TDC?

Answer #1

Use this pistons TDC. Since the block, and head have been decked and I am using a different size head gasket then stock things are a lining up like they would on a stock engine. Also the crank pulley is useless and I need to make new marks on it somehow.



Issue #2 (Solved)

Timing chain marks are inconsistent

When I time the engine, I first set the crank keyway to match the blocks line, put the crank sprocket on the crank, and then put the cams in with the dowels facing 10 o'clock on the intake and 12 o'clock on the exhaust side. I then install the chain and put one of the silver timing marks on the chain on each timing mark on the crank sprocket, and each cam gear.

All is good until I spin the engine. I can never get the timing marks on the chain to match back up to the timing marks on the crank sprocket or cam gears. (this has happened on aftermarket and stock cam gears)

Question #2 (Solved)

Are all FWD sr20 timing chains the same?

Answer #2

Yes

Question #3

Are all sr20 crank sprockets the same?

Question #4 (Solved)

Should I be setting the cams on the high or low lobes?

Answer #4

Does not matter at this point. It will matter when I degree the cam shaft. I should do this on the high lobe.

Question #5 (Solved)

Does anyone have a way to lock the engine in VVL temporarily with compressed air?

Answer #5

No, compressed air will not work. However I can lift the high lobe rocker pad up with my finger and once I spin the engine it will lock the cam on the high lobe for the remainder of the cams cycle.

Obviously, I am beyond confused and that is why I am here asking for help.

I do have an crank degree wheel and dial indicator gauge to help solve these issues. Also I ordered one of these nifty tools from mazworx last night. Hopefully once I figure out what TDC to use (crank or piston) I will be able to just time the engine with this thing. Spoiler

This one I can shed some light on. The reason your marks never match up after rotating the engine, is because it takes 50ish rotations inbetween matches. They never match on two consecutive revolutions, you must always rotate the engine for about 5-10 minutes depending on how fast you can rotate it inbetween matches.

Wow I didn't realize it took that many rotations. I must of rotated the engine a good 20-30 times before i freaked out and reset everything.

Ill see if I can get it to match up from rotating it a million times. thanks @Dala

Yes and no. Here is my 98 SE-R at TDC:



My 97 SE-R didn't have that yellow mark. I don't know how nitpicky you wanted an answer though. If you mean the number of links being the same, then yes. Also 98's don't have that dopey timing chain guide (two 12mm bolts) - but the holes in the block are still there.

Just to put some closure on this thread.

The tool from mazworx worked great, my engine is fully timed and ready to go.

Great to hear. So what type of pistons and rods did you go with?