The keyway on series four and the first generation is exactly at nine o'clock when viewed from the front looking aft.

When the keyway is in that position, the timing pointer will be opposite TDC. IF you put a first generation pulley from a first generation carb car on your series four, you will find the first mark on that first gen pulley will be right opposite that pointer.

Since there is NO TDC mark on a series four cars pulley, the nearest mark to the pointer will be the LEAD mark which is 5 degrees ATDC and the mark after that the 20 degree Trail mark.

If you wallowed out the holes in your pulley where it will fit in any of the four possible positoins...........on the whole your screwed. Even though common sense tells you to put the eccentric shaft where the keyway is at nine o'clock and then install the pulley with the marks aligned near to the pointer, there will be TOO MUCH SLOP in the four bolt holes for it to be installed right. Even a pulley with the holes not wallowed out has SLOP in it and you can bias that pulley on either side of the pointer and then tighten the screws down and be off five degrees or more.

And when I said put a first gen pulley on a S4, only three of the four holes will match, BUT if the keyway is to the nine o'clock positon, the TDC mark on the first gen WILL align with the fixed timing pin. Been there, done that.

And you can read the following thread and it will give you a slight clue on how to find TDC and make marks on the pulley. BUT it is in ERROR and cannot be used for a series four pulley/engine. That article must have been meant for a first gen carb engine or RX-3 whatever. This thread: http://members.optusnet.com.au/~onec...-%20part%20one

Read it and you'll figure out just why. But it will give you an idea on how to find TDC on your pulley and make marks on it.

And let's see. This is a mass manufactured engine/ car, and I'm to believe that somehow the pulley and hub are each and all *one off custom built*?????????? I think about that and have real problem with that concept. Especially when I can put a first gen pulley on my S4 engine and the TDC on the first gen aligns with the fixed pointer. First gen had LEAD at TDC.

 

Depends on Load. With a RTEK2.0 you see the normal L5ATDC and T20ATDC under 1100 rpm. If you gently rev the engine over the 1100 rpm, the L goes up to about 14 degrees BTDC for Lead and 4 degree BTDC for Trai. MEMORY THERE.

At 3000 in fifth and just maintaining the speed limit sorta, the timing both Lead and Trail, will be in the 35 degrees ATDC range. Stomp on the pedal and the timing decreases considerably due to the load. Turbo car, na might be diff.

Attached is a stock turbo timing *map*. At least a part of it. It's a load vs the rpm. See the black 40 degrees? Now go straight up and see how the timing decreases as the Load goes up at the same rpm. The 40ATDC is the largest number I remember seeing.

 

Hailers is my hero!

 

that table doesn't look right, timing should advance not retard with load, in turbo applications it should retard about 1 degree per psi above 2-3psi which is what most tuners use as a rule of thumb on pump gas for a base starting point. that or you have BTDC mixed up with ATDC.. and yes i know that is a vacuum table not pressure.

 

Aha, so you're saying that adding boost makes your engine retarded and engines with no boost are advanced? I'll have to remember that!

Sorry, couldn't resist. :P

 

go suck on some 87 octane

 

Those are all ATDC.

 

because the leading mark on my current s5 pulley is at arround 10 o'clock( the trailling mark is in almost at 9 oclock, same as shaft key. the paint on pulley is gone and i see small dimples but i dont thin k these are the right marks. i think these dimples on pulley r wrong can u agree???????

 

those timing numbers still do not look even remotely right.

timing under a moderate load should be in the 30 degree BTDC range not ATDC, when moving into boost it should ramp down to about 15 degrees BTDC under hard loads (~15PSI). i would be surprised if the engine even ran if those numbers are ATDC or the load table does not represent actual engine load.

 

At 8 psi I am right around 18 degrees BTDC. Sound about right?

 

yep, that is about perfect for a basic starting point for fine tuning the timing.

 

Awesome, thanks!!!!

 

you could probably even advance it a bit more safely if you have a decent setup like front mount and run only 91 octane or better.

 

ok, this is simple if you are limber. strip part of the insulation off the L1 spark plug wire. unbolt the exhaust. now stick your leg by the exhaust port and grab hold of the L1 wire. at idle it should shock you .14sec before the hot exhaust gas hits your leg. get it within ~.008sec and you should be good to go.

 

Well fudge. It should be BTDC not ATDC for those figures. Those are the stock MAZDA timing maps.

Driving at 3000 rom in fifth the timing is around 36 BTDC. Go to fourth gear and the stomp the pedal and get into boost, the timing goes much lower but then advances again where I'll see in the 20 BTDC. Mid 20's.

Henrik posted the timing some time this year on this forum. You must have missed it. Do a SEARCH. Kinda fuged up when I cut and paste it.

Leading
1024 1280 1536 1792 2048 2304 2560 2816 3072 3328 3584 3840 4096 4352 4608 4864 5120 5376 5632 5888 6144 6400 6656 6912 7168
14.4 17.9 16.8 23.2 27.0 29.8 33.0 35.8 40.4 38.6 37.2 36.9 36.9 29.8 32.0 35.5 35.5 35.5 35.5 35.5 35.5 42.5 42.5 42.5 42.5
14.4 17.9 16.8 23.2 27.0 29.8 33.0 37.6 40.4 38.6 36.2 36.5 36.2 29.1 31.3 34.4 34.4 35.1 35.1 35.1 35.1 42.1 42.1 42.1 42.1
20.0 20.7 22.5 26.3 29.1 30.5 31.3 33.0 34.1 33.7 32.7 31.3 36.9 29.8 29.8 29.8 29.8 29.8 29.8 29.8 29.8 36.9 36.9 36.9 36.9
19.3 20.7 23.5 26.0 28.4 29.5 30.5 32.0 33.4 33.4 33.4 33.4 36.9 29.8 29.8 29.8 29.8 29.8 29.8 32.0 32.0 36.9 36.9 36.9 36.9
17.9 21.1 24.2 25.6 27.7 28.8 29.8 31.3 33.0 33.4 34.1 34.4 34.8 27.7 28.8 28.8 28.8 33.7 33.7 34.8 34.8 36.9 36.9 36.9 36.9
13.7 17.5 21.1 23.2 25.3 26.7 27.7 29.1 30.5 31.3 31.6 32.3 33.0 26.0 29.1 29.1 29.1 36.2 36.2 36.9 36.9 36.9 36.9 36.9 36.9
9.5 14.0 18.2 20.4 22.5 23.9 25.3 28.4 28.4 28.8 29.1 29.8 30.5 25.6 30.5 30.5 30.5 34.8 34.8 36.9 36.9 36.9 36.9 36.9 36.9
6.6 10.9 15.4 17.5 20.0 21.4 22.8 24.2 26.0 26.7 27.0 27.7 28.4 25.3 31.3 31.6 31.6 33.4 33.4 35.8 35.8 36.9 36.9 36.9 36.9
4.2 8.0 12.3 14.7 17.2 18.9 20.7 22.1 23.5 24.2 24.9 26.0 26.7 26.7 29.5 31.3 31.3 33.0 33.0 35.5 35.5 36.9 36.9 36.9 36.9
3.1 6.3 9.5 11.9 14.4 16.5 18.2 19.6 21.1 22.1 22.8 24.2 24.9 24.9 28.1 30.5 30.5 33.0 33.0 35.5 35.5 36.9 36.9 36.9 36.9
2.4 4.9 7.0 9.5 11.9 14.0 15.8 17.2 18.6 19.6 20.7 22.1 23.5 23.5 26.7 29.8 29.8 32.3 32.3 35.1 35.1 36.9 36.9 36.9 36.9
2.4 3.5 4.9 7.0 9.1 11.6 14.0 15.1 16.8 17.9 18.9 20.4 21.8 21.8 25.6 28.8 28.8 31.6 31.6 34.1 34.1 35.8 35.8 36.9 36.9
2.4 2.4 2.1 4.9 7.0 9.5 11.6 13.3 14.7 16.1 17.2 18.9 20.4 20.4 24.2 27.4 27.4 30.5 30.5 33.4 33.4 35.5 35.5 36.9 36.9
2.4 1.7 1.0 3.5 5.9 8.0 10.2 11.6 13.0 14.0 15.4 17.5 18.9 18.9 22.8 26.3 26.3 29.1 29.1 32.0 32.0 34.8 34.8 36.9 36.9
2.4 1.7 1.0 3.5 5.9 8.0 10.2 10.9 11.6 13.0 14.0 16.1 17.9 17.9 21.8 24.6 24.6 28.1 28.1 30.5 30.5 33.4 33.4 35.5 35.5
2.4 1.7 1.0 3.5 5.9 8.0 10.2 10.9 11.6 12.3 13.0 15.1 16.8 16.8 20.7 23.2 23.2 26.7 26.7 29.1 29.1 30.5 30.5 30.5 30.5
2.4 1.7 1.0 3.5 5.9 8.0 10.2 10.9 11.6 12.3 13.0 14.7 16.5 16.5 20.7 22.8 22.8 20.7 20.7 23.5 23.5 28.4 28.4 28.4 28.4
2.4 1.7 1.0 3.5 5.9 8.0 10.2 10.9 11.6 12.3 13.0 14.7 16.5 11.6 15.8 17.9 17.9 20.7 20.7 23.5 23.5 28.4 28.4 28.4 28.4
2.4 1.7 1.0 3.5 5.9 8.0 10.2 10.9 11.6 12.3 13.0 14.7 16.5 11.6 17.9 17.9 17.9 20.7 20.7 23.5 23.5 28.4 28.4 28.4 28.4

Trailing
1024 1280 1536 1792 2048 2304 2560 2816 3072 3328 3584 3840 4096 4352 4608 4864 5120 5376 5632 5888 6144 6400 6656 6912 7168
14.4 17.9 15.1 23.2 27.0 29.8 35.1 37.2 38.6 36.9 40.4 48.1 48.1 41.1 42.5 42.5 43.9 43.9 49.5 49.5 49.5 49.5 56.6 56.6 56.6
14.4 17.9 15.1 23.2 27.0 29.8 35.1 37.2 38.6 36.9 40.4 46.7 46.7 39.7 42.5 42.5 42.5 42.5 46.7 46.7 46.0 46.0 53.0 53.0 53.0
14.4 17.9 32.3 34.1 35.5 35.1 35.1 37.2 38.6 39.0 40.4 38.6 37.2 30.2 32.0 32.0 32.0 32.0 32.0 32.0 29.8 29.8 36.9 36.9 36.9
20.0 25.6 28.1 30.2 32.3 32.7 32.7 31.6 34.8 35.1 35.5 35.8 36.2 29.1 29.8 29.8 29.8 29.8 29.8 29.8 32.0 32.0 36.9 36.9 36.9
20.0 21.4 22.5 24.9 27.7 29.1 30.2 31.6 32.7 33.0 33.4 34.1 34.8 27.7 29.1 29.1 29.8 29.8 33.7 33.7 34.8 34.8 36.9 36.9 36.9
11.2 18.6 21.1 23.2 25.3 26.7 27.7 29.1 30.5 30.9 31.6 32.3 33.0 26.0 29.8 29.8 30.5 30.5 36.2 36.2 36.9 36.9 36.9 36.9 36.9
8.8 13.3 17.9 20.4 22.5 23.9 25.3 26.7 27.7 28.4 29.1 30.2 30.9 26.0 30.5 30.5 31.6 31.6 34.8 34.8 36.9 36.9 36.9 36.9 36.9
4.5 8.8 13.3 16.1 18.9 20.7 22.1 23.5 25.3 26.0 26.7 27.4 28.4 25.3 30.2 30.2 30.5 30.5 32.7 32.7 34.8 34.8 36.5 36.5 36.9
-1.8 3.1 8.4 11.2 14.0 15.8 17.5 19.6 21.4 22.5 23.9 24.9 25.6 25.6 27.4 27.4 28.4 28.4 29.8 29.8 32.7 32.7 34.4 34.4 36.2
-9.2 -3.6 2.4 5.2 8.0 10.2 12.3 14.0 16.1 17.5 18.9 20.4 21.8 21.8 23.5 23.5 25.3 25.3 26.7 26.7 29.1 29.1 31.3 31.3 33.4
-13.0 -8.8 -4.6 -1.8 1.0 3.5 5.9 7.7 9.5 10.9 12.3 14.0 15.8 15.8 18.2 18.2 20.7 20.7 22.8 22.8 25.6 25.6 27.7 27.7 29.8
-13.8 -12.0 -10.2 -7.8 -5.3 -2.5 0.3 2.1 3.8 5.2 6.6 8.4 10.2 10.2 13.3 13.3 15.8 15.8 18.6 18.6 21.8 21.8 24.2 24.2 26.3
-13.8 -13.8 -13.8 -11.3 -8.8 -6.4 -4.3 -2.5 -0.4 1.0 2.4 4.2 5.9 5.9 9.5 9.5 12.3 12.3 14.4 14.4 18.2 18.2 20.7 20.7 22.8
-13.8 -14.5 -15.2 -12.7 -10.2 -7.8 -5.7 -3.9 -2.5 -1.4 -0.4 1.7 3.5 3.5 7.3 7.3 10.2 10.2 12.3 12.3 15.4 15.4 18.2 18.2 20.4
-13.8 -14.5 -15.2 -12.7 -10.2 -8.1 -6.0 -5.0 -3.9 -2.9 -1.8 0.0 1.7 1.7 5.9 5.9 8.8 8.8 11.6 11.6 14.0 14.0 16.5 16.5 18.9
-13.8 -14.5 -15.2 -12.7 -10.2 -8.1 -6.0 -5.3 -4.3 -3.6 -2.9 -1.1 0.7 0.7 4.9 4.9 7.7 7.7 10.9 10.9 13.7 13.7 9.8 9.8 9.8
-13.8 -14.5 -15.2 -12.7 -10.2 -8.1 -6.0 -5.3 -4.6 -3.9 -3.2 -1.4 0.3 0.3 4.5 4.5 7.3 7.3 0.7 0.7 3.5 3.5 8.4 8.4 8.4
-13.8 -14.5 -15.2 -12.7 -10.2 -8.1 -6.0 -5.3 -4.6 -3.9 -3.2 -1.4 0.3 -9.5 -5.3 -5.3 -2.5 -2.5 0.3 0.3 3.1 3.1 8.0 8.0 8.0
-13.8 -14.5 -15.2 -12.7 -10.2 -8.1 -6.0 -5.3 -4.6 -3.9 -3.2 -1.4 0.3 -9.5 -5.3 -5.3 -2.5 -2.5 0.3 0.3 3.1 3.1 8.0 8.0 8.0

Split
0.0 0.0 1.8 0.0 0.0 0.0 -2.1 -1.4 1.8 1.8 -3.2 -11.3 -11.3 -11.3 -10.5 -7.0 -8.4 -8.4 -14.1 -14.1 -14.1 -7.0 -14.1 -14.1 -14.1
0.0 0.0 1.8 0.0 0.0 0.0 -2.1 0.4 1.8 1.8 -4.2 -10.2 -10.5 -10.5 -11.3 -8.1 -8.1 -7.4 -11.6 -11.6 -10.9 -3.9 -10.9 -10.9 -10.9
5.6 2.8 -9.8 -7.7 -6.3 -4.6 -3.9 -4.2 -4.6 -5.3 -7.7 -7.4 -0.4 -0.4 -2.1 -2.1 -2.1 -2.1 -2.1 -2.1 0.0 7.0 0.0 0.0 0.0
-0.7 -4.9 -4.6 -4.2 -3.9 -3.2 -2.1 0.4 -1.4 -1.8 -2.1 -2.5 0.7 0.7 0.0 0.0 0.0 0.0 0.0 2.1 0.0 4.9 0.0 0.0 0.0
-2.1 -0.4 1.8 0.7 0.0 -0.4 -0.4 -0.4 0.4 0.4 0.7 0.4 0.0 0.0 -0.4 -0.4 -1.1 3.9 0.0 1.1 0.0 2.1 0.0 0.0 0.0
2.5 -1.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.0 0.0 0.0 0.0 -0.7 -0.7 -1.4 5.6 0.0 0.7 0.0 0.0 0.0 0.0 0.0
0.7 0.7 0.4 0.0 0.0 0.0 0.0 1.8 0.7 0.4 0.0 -0.4 -0.4 -0.4 0.0 0.0 -1.1 3.2 0.0 2.1 0.0 0.0 0.0 0.0 0.0
2.1 2.1 2.1 1.4 1.1 0.7 0.7 0.7 0.7 0.7 0.4 0.4 0.0 0.0 1.1 1.4 1.1 2.8 0.7 3.2 1.1 2.1 0.4 0.4 0.0
6.0 4.9 3.9 3.5 3.2 3.2 3.2 2.5 2.1 1.8 1.1 1.1 1.1 1.1 2.1 3.9 2.8 4.6 3.2 5.6 2.8 4.2 2.5 2.5 0.7
12.3 9.8 7.0 6.7 6.3 6.3 6.0 5.6 4.9 4.6 3.9 3.9 3.2 3.2 4.6 7.0 5.3 7.7 6.3 8.8 6.3 7.7 5.6 5.6 3.5
15.5 13.7 11.6 11.3 10.9 10.5 9.8 9.5 9.1 8.8 8.4 8.1 7.7 7.7 8.4 11.6 9.1 11.6 9.5 12.3 9.5 11.3 9.1 9.1 7.0
16.2 15.5 15.1 14.8 14.4 14.1 13.7 13.0 13.0 12.7 12.3 12.0 11.6 11.6 12.3 15.5 13.0 15.8 13.0 15.5 12.3 14.1 11.6 12.7 10.5
16.2 16.2 15.8 16.2 15.8 15.8 15.8 15.8 15.1 15.1 14.8 14.8 14.4 14.4 14.8 17.9 15.1 18.3 16.2 19.0 15.1 17.2 14.8 16.2 14.1
16.2 16.2 16.2 16.2 16.2 15.8 15.8 15.5 15.5 15.5 15.8 15.8 15.5 15.5 15.5 19.0 16.2 19.0 16.9 19.7 16.5 19.3 16.5 18.6 16.5
16.2 16.2 16.2 16.2 16.2 16.2 16.2 15.8 15.5 15.8 15.8 16.2 16.2 16.2 15.8 18.6 15.8 19.3 16.5 19.0 16.5 19.3 16.9 19.0 16.5
16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 15.8 15.8 15.8 16.2 16.2 16.2 15.8 18.3 15.5 19.0 15.8 18.3 15.5 16.9 20.7 20.7 20.7
16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 18.3 15.5 13.4 20.0 22.9 20.0 25.0 20.0 20.0 20.0
16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 21.1 21.1 23.2 20.4 23.2 20.4 23.2 20.4 25.3 20.4 20.4 20.4
16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 16.2 21.1 23.2 23.2 20.4 23.2 20.4 23.2 20.4 25.3 20.4 20.4 20.4

 

Something like the attached jpg. The TELLTALES tell the high/low of each item.

 

Engineering student?

 

i've been out of school long enough to forget all that bs. it's all practical application now.

 

oh i know HAILERS i was just letting you know it wasn't ATDC so you wouldn't try correcting the wrong way and at the same time making sure i wasn't misreading anything. i setup the timing map on my microtech so i knew something was amiss with that table being ATDC.

 

ok, to line up your pulleys you have to look for the dot on each pulley. Then line the dot up with each pulley. All the holes should line up with the e-shaft. That simple!!!!!!! Also all pulleys are the same from s4-s5 and re cosmo. Im running the re cosmo pulleys so that I can run a serpatine belt and still use the v-belts for the ac/ps.
Thanks Robert

 

this has already been discussed and is not true, pulleys are matched to hubs and marked as a paired set so moving a pulley to a different hub may result in the timing marks being off.

 

That is not true! I have many times switched out pulleys and never had a timing issue. When you get a chance check it out.
Thanks Robert

 

So? How does that work? Every eccentric shaft has the keyway cut by a machine in the very same spot. There can only be one TDC in relation to that keyway. I find it hard to believe the four attach holes for the pulley are not done by a machine and drilled in the same spots each and every time for each and every pullley/hub and that the holes in the pulleys are not drilled in the same fixture and drilled in the same place each and every time.

Just hard to believe in the age of mass production. Just give me a reason to believe there'd be a reason for custom drilling each pulley/hub so it'd make sense.

NOT saying your/they are wrong, it just does not make sense.

 

it is true, i experienced this myself. i mixed pulleys and hubs and then had really screwed up timing. i have also had 2 different shops confirm this. when a put a matched pulley and hub on the engine it ran perfect. i have a 3/4 inch drive 19mm socket for getting those pesky eccentric shaft bolts off. it works great with my 3/4 inch breaker bar.

 

i found it hard to believe myself but who really knows, all i know is after reading about it a number of people experienced that the timing marks were not always exact between the pulleys and hubs. maybe most of them were close enough to not affect anything seriously but in more serious cases a bit of extra advanced timing could cause some serious problems.

you have to think a little differently vs piston engines, the rotors are cast and a little bit of tolerance in the e-shaft machining, rotor gears and how the gear sits in the cast rotor could all affect slightly how the engine is timed so possibly that is why the differences exist so checking the timing marks would just be a safety precaution if you are not using the same parts for your reassembly.