24TEN

iTrader: (2)

The number of teeth on the crank gear and cam gear dictate that. With that said, rest assured the ratio doesn't change. It's a fixed whole number ratio so it will not advance with every rotation.

Caoboy

So then that would indicate that if he puts the y8 cam gear on, and it's at tdc, but does not line up with the belt on tdc, he should put the b7 gear on and and see if that lines up with the belt.

If that doesn't his last resort is an adjustable cam gear for a y8.

The other variable in the equation is his belt. He said he's using a 103 tooth belt (iirc from one of his many threads) from a honda city, and we don't have that particular belt here in the states, could it be that this is also causing an issue with the way we are diagnosing his predicament?

osix

I been checking info on the Engine .
And someone gave me this data.

I have not verify it else where. but here what i got ,


D15B2 Spec.
+ Displacement : 1493 cm3
+ Bore and Stroke : 75 mm X 84.5 mm
+ Compression : 9.2:1
+ Power : 92 hp @ 6000 rpm & 89 ft·lbf @ 4500 rpm

Thailand spec.
+ Displacement : 1493 cm3
+ Bore and Stroke : 75 mm X 84.5 mm
+ Compression :
+ Power : 91 hp @ 6000 rpm & 85.5 ft·lbf @ 4000 rpm

----------------------------------
is there data on the Number of Tooth on th Camgear.


Currently i am at 20*Degree TDC .
A Racing workshop told me that i am Off by 5* degree .
but i got not much idea what he really meant .

----------
i am collecting Data from teh piston to the Storke and so on to determine if i need to do more .

I Change it to B7 Camgear base on suggestion and it seem like i am just a little off.
But having the Ignition timing Retarded to the MAX - seem like my only option now is to adjust the Camgear again , but if i am goign to retard the Camgear by 5* is almost the same as using back the Y8 Camgear ?

Carroect me if i am wrong .
Anyone have any expereince ?

Seem like is a B2 Block - Should i find B2 camgear ?




also from D-series forum

Wow he is getting 37 ? and 44mpg i barely Hit 30mpg Mark . what should i do to reach that

and also he is saying he is settin it 23BTDC wow . Mine is now 20BTDC i think

but before i went to set it with a timing light . i think i was running like 30 BTDC or more and the car have so much Push and you can feel the power .

TomCat39

The D15B2 and the D15B7 are pretty much the exact same block as far as I know.

The only aspect I am not sure on is the deck height on the D15B2. It has the exact same rods and pistons and I think the crank is the same too.

@caoboy your second post pretty much somes up my understanding. On the belt portion though, if the teeth mesh with either stock gear I don't see it being an issue. Also length of belt only dictates looseness or tightness. The teeth spacing is still the same regardless of length.

The one thing I did notice right off is the key way position is different between the B7 camshaft and the Y8 camshaft. The write ups always attribute the 4.75° to the deck height change between the D15 blocks and the D16 blocks.

I figured, I have all the parts downstairs in the workshop so I might as well mock it up with pictures and shed some light on it all.

24TEN

iTrader: (2)

I think it's a combination of everyone over complicating the difference of half a tooth to be honest LOL

I've been biting my tongue since this thread started because of the lack of concrete information on this "CV" stamped engine block. But I'll state that if this engine is truly equivalent to a D15B"X" engine then the PM3B cam gear "should" be correct.

The distance between the camshaft and the crankshaft doesn't change once the head is installed so trying various belts to compensate for the difference in cam position will have zero effect. I believe someone had stated this earlier so kudos to someone who understood that. That said, for sure it's a newer 96+ style head. I leave it generalized like that for simplicity's sake. We know that, at least in the US, all 96-00 D-Series engines were 1.6 and use the same cam gear which we will reference as the Y7/8 cam gear. This only leaves the block to be the deciding factor in changing the cam's TDC location relative to the crankshaft's TDC location (in a simple world anyway...).

I can't go through the details while I'm at work because it's a very in depth subject as to why you need to swap gears nor will I ever try to type everything out on my phone to explain this later so if anyone wants to try to explain it or link it, by all means go for it. What I'll do instead is give you the most basic visual interpretation time will allow me to do right now.



(Pulled image from google, if the owner is on here and would like it removed, please IM me)

Notice the Y7/8 camgear key is slightly off center leaning towards the left of the picture (use the word "UP" on the gear as the reference AND/OR the timing marks if you have really good eyes). Notice that the PM3B gear has the key pretty much dead center. Notice that they are both level with one another. That's the difference of half a tooth visually. So if in a perfectly unmolested D16Y"X" engine the key is leaning just left for TDC wouldn't it be arguable that with the PM3B gear in combination with a D15B"X" block and D16Y"X" head, that's where you'd want it to be as well? As stated none of the timing marks on the PM3B gear will work so all you're left with is visual confirmation backed by the ability to set ignition properly. I'd venture a guess that by using the PM3B cam gear the left mark will be slightly below the head surface and the right mark will be slightly above (I mean, it's half a tooth difference right?).

What I'd also throw out there is my own observation of a newer D15B my neighbor got from a local importer. It was stamped D15B, had the newer style head (non VTEC but with Y8 style manifold), and a PM3B cam gear. Nothing was touched, just swapped to replace an old blown engine.

NOW...to throw the curve ball.

What if this "CV" engine is equivalent to a D15B...VTEC? They had newer versions of this as well so what if it was never head swapped? What if someone swapped the camshaft with an equivalent Z6 style camshaft? Or what if it was and older version that some trashed the head on, replaced with a newer head but reused the older Z6 camshaft? These aren't things we can confirm with absolute certainty. In addition, do you know what the stock ignition timing is for that ECU? Here in the states, newer D16Y"X" engines were set at 12*BTDC while older ones were 16*BTDC. What's the ECU originally supposed to be at and is the crank pulley marked accordingly? No way to tell over the internet without you doing some leg work. So going back to my first statement of this post:

Why can't you just move the cam gear one tooth and reset your ignition timing? If it gets worse, then you know to move 2 teeth the opposite direction and try to set ignition timing again. If it over shoots the timing marks for ignition, that should be a dead give away to swap to the other cam gear and repeat the process.

Also, would like to comment on this post you made:

If you move the cam gear one tooth, you will provide the distributor room to adjust because it will no longer be set at 20*BTDC. That measurement is only valid with the camshaft being installed at that position relative to the crankshaft.

osix

what i notice is when i i set the B7 Camgear at the workshop is that the 3/9 O'clock mark or the center of the Camgear is Lower if i use the D16y8 Back panel Marking.


The red arrow being the Mark .

I wonder if this will shed some light on the Block height also .

-----------------
being set to Retard i have lots of room to Advance it.
I wonder what would be the Best setting .
Finger boss and reading on

And also i want to Thanks you guys for sharing .
I did notice that if i Advance my Ignition timing more.
Say up adding 5-10* more i do get a very powerful Engine
The question is will i kill it . or over do it .


i am using Octane 91 ?
I wonder if i use E85 ? Gashol will i damage the Engine ? or it will just Chew it up .

TomCat39

Not to detract from you or even side track the thread but to gain a clearer understanding I need to ask.

The way I was perceiving this is that the D15 block height is lower than the D16. So when you put the D16 head onto the D15 block, the camshaft and the crank shaft are X mm closer together than what the D16 Head cam gear was designed for. Thus the half a tooth off. Not saying there is a change between the two once the two are married, just there is a difference between the two shafts when comparing an all D16 motor to a D15 block/D16 Head motor.

Am I confusing things?

24TEN

iTrader: (2)

That's correct. My statement was more backing what you had said before. Once the head and block are assembled, changing the length of belt being used does nothing to change the orientation of the cam relative to the crank...unless it's so big there's no tension. Simply put, the distance (specifically the tangent point of the cam gear to the tangent point of the crank gear) won't change unless the block height changes which is why I was asking earlier if the OP can measure the deck height. 207mm is 1.5 and 212mm is 1.6. Again, there's the difference, 5mm or .5cm. That change translates to the half tooth difference via the cam gear.


Earlier I had seriously drawn out diagrams with the equations to be used to back everything in Autocad just to visually verify and mathematically verify all aspects. Then I started to think about all the possible scenarios and it was just too much to cover so that lead me to just keeping it simple. You can see the difference in the gears with the picture posted, some common sense shows you where the key way should be on a 1.6 block so just try to get it back there.

EDIT: Now that I read back what you quoted, really what I meant to say is the distance between the "camshaft" and "crankshaft" doesn't change once the head is installed. I'll update my post.

TomCat39

I gotchya 24TEN. I totally misunderstood your comment. I thought it implied someone was saying the distance would change once the two were mated and you were correcting that erroneous statement.

Anyways, here is some pics I just took so you can see exactly why changing cam gears is the fix and why the timing marks will NOT match if you are using the B7 gear. And even see how it is literally half a tooth variance between the two gears.

An let me say this to osix. You run the timing belt from the crank gear at the bottom of the engine up to the left side of the cam gear to put it on. It will be painfully obvious that the teeth missalign half a tooth as the teeth are precisely spaced and sized to match the gears. Please see the pics to understand why switching the gear adjusts for the distance change of the shorter block and why the B7 gear is the fix.

I set the Y8 gear on top of the B7 gear and aligned the key's and centered the camshaft holes etc. The first two pictures show the key's aligned:




These next 3 pictures show the difference in the mechanical timing marks between the two gears and show exactly where on the B7 gear you would have to mark to have an accurate 3 & 9 o'clock mark for the Y8 camshaft. You would of course just copy the marks over to the B7 gear and ignore the stock B7 engravings:




And this last picture shows how the teeth are exactly half a tooth off. Keep in mind, I stacked the gears precisely and then took all these pictures. I did not touch the gears after stacking them so all these pictures are from the exact same positioning and orientation.

osix

I have that in Mind when i hunt the B7 cam gear at the Junkyard and believe that it would correct the 4.75* error .

Y8 Camngear ( the car is running normal - but when i go uphill i got no power at all . i got to shift to Gear 2 and yet it still feel weak .
- Ignition Tming set at Advance ( MAX OUT )

B7 gear ( the car now run fine but i can feel is kinda Off. - after setting it with a Timing Light ( local racing workshop ) the guy told me that i am Off by 5* which he said i should be 15* degree .

But running the car i can feel that something is missing - I am considering adjusting it to maybe 25* degree - 30 Degree off BTDC or is it TDC .

for the same reason ( i am summing i understand you ) that since it would not match marking. it would be safe to go beyond the marking . the question is how Far or how much ?

Anyone have any idea on this ?

Ignition timing now on Retard ( MAX ) so i do have a large gap of Adjustment to play with .

TomCat39

The pictures above show you exactly where the marks should be.

Or do like I wrote earlier, slide the Y8 gear on to put the cam shaft TDC with the marks on the Y8 gam gear. Then slide the gear off and slide on the B7 gear. Then install the timing belt and then you can install and torque the cam gear bolt. Mechanical timing will be set and then you can do your ignition timing via timing light with the crank pulley marks if it's supposed to be at 16 degrees BTDC.

24TEN brought to light another one of the challenges that you may be facing. Different years have different ignition timing requirements. The 92-95 USDM cars is 16 degrees BTDC and is the red (middle) mark of the 3 marks together on the crank pulley.

Your car being foreign to USA could have a different ignition timing requirement. Your ECU is not USDM so it will dictate what ignition timing you actually need.

You don't typically advance or retard mechanical timing, usually you advance or retard ignition timing with the distributor. These two types of timing is not the same and cannot be considered the same.

The cam gear change is to fix mechanical timing. You still have to learn what ignition timing your car requires.

eghatch9295

iTrader: (1)

for posterity's sake, the b2, b1, b8 and b7 have the same deck heights.

TomCat39

osix

Is there a Way or someone with experience to tell . how much or how many Degree are we looking at for TDC .

currently i am already 20* off .

Assuming what been told is that after the mod it would not line up with the Mark .
base on the info we got , how much will be the different from the marking.

what would be a good way to tell and if there is alternative for TDC . adjustment for ignition timing adjusting the distributor after set up the camgear

TomCat39

I'm sorry but you have all the information in this thread already how to set your mechanical timing.

You will have to research ignition timing for your country and car as it's not information we will have.

If you are still confused, please research mechanical timing and then research ignition timing so that you know the difference.

eghatch9295

iTrader: (1)

some people like to buy unfinished projects. some people also like to be spoonfed all of the information they need to finish their cars.

osix

is not spoon feeding , i am looking for people who have done this mod before . so to shel some more info, i habe plan to test the Y8 camgear and again on the B7 camgear.

the info you provided have been very useful but still missing part of the math .

anyone can point me to any link that teaches you how to caculate the Camgear degree to Ignition Timing Ratio .

in simple term .>
The effect of mechanical timing over Ignition timing .

i been trying to search , if anyone have a good direction do share .

24TEN

iTrader: (2)

They are separate. Set mechanical timing first then set ignition timing. Whoever is working on this for you has already told you that mechanically it is one tooth off. By your own math you've deduced that one tooth is roughly 9.5* which means, without touching the distributor, you'll gain that +/- 9.5* depending on which direction you've adjusted the gear.

To answer your question ignition timing is based off of the mechanical timing so you need to address mechanical timing first.

osix

Update -

Camgear changed. - Car driving but a few weird point .

1. The car run fine , but now when i drive say at 5th gear now . and when i Clutch in the Car Stall while the car is moving .



2. Adjusted the valve twice .
2.1 Intake 0.08 - out - 0.10 ( car keep stalling when i clutch in )
2.2 Intake 0.07 - out 0.09 ( Cars stall when clutch in on 5th or 4th gear. but jump start when i let go clutch - but if i clutch and brake car would stall while slowing down )

3. Idle seem a little unstable

4. i am guessing the PM8B Camgear may not be set right , so i am confuse now .


5. We set TDC using the old school method of using a long metal obkect to stick into the 4th spark plug channel . turn it to the highest point . we did that a few time. and from there

6. Car went for a 400km test drive . uphill improved

7 manage to get about 38mpg for the long trip

8 city + highway mix drop back to 23mpg

we adjust it off setting it 1 tooth at a time .

if any of his make sense trying to explain it correctly

TomCat39

You are over complicating things.

Follow the factory sevice manual to set the crank gear to tdc.

Set the Y8 cam gear to TDC via the UP and left and right marks of the gear. Now pull off the y8 gear and slide on the b7 gear. The camshaft is still TDC.

Now install your timing belt and for extra good measure, place black permanant marker marks on the b7 gear indicating the head level and the correct "up" marking. This could be copied right off the Y8 cam gear.

The variance is literally 4.75 degrees.

You mechanical timing is set properly at this point. Set your timing belt tension and torque all your bolts etc (including the cam gear bolt) and then you can warm up the car and set your ignition timing to the setting that is proper for your country of origin ECU specification.

The ignition timing specification is the info we don't have as your car is not from the US Domestic Market (USDM) or the Canadian Domestic Market (CDM) and I don't think your ECU is either.

Ignition timing is set with a timing light. The car warmed up and the service connector jumped.

osix

We Did like what you said . but the car fail to move off . right after we did that . it stall when moving off and clutch in and feel lack of power.

we tested the combination and adjust it tooth by tooth over 3 time.

each time setting the TDC using the Old screw driver trick .

After some test . the last time we did that . the result wa sthe car did not have power to go uphill .

Second try . the car got too weak to even move off and clutch in .

3rd Try the car sound normal and drive normal ( adjusting 1 tooth different to test it )

-------------------------

Today i went to adjust the trottle body and using a meter to check trottle opening setting as well as wash the clean the IACV . set the timing using a Timing gun . and manage to get perfect TDC .


1. now the idle is running about 900-950
2. air flow screw don't seem to work . ( to reduce further )
3. Car running fine .
4. fuel ecomony getting about 26mpg city 70% 30 % highway

--------------
Workshop suggest .

1. change intake manifold to 96 manual and it IACV MT
2. ECU P08
3. Rewrie
4. if needed adjustable Camgear
5. Timing Belt if needed.

--
Any feedback ?