Cam Shafts

[mike323]

Originally posted by demoninvictus
well.. there are not a lot of shops around here that do 'Internal' engine work as they say... and not alot of shops that are experienced in mazda's .. maybe a few dsm's, and a ton of honda's, but are seemingly afraid of the bp.. for no reason i would assume just the fact that not alot of protege guys around here do that kind of work to their engines. one shop wanted to charge me 6 - 8 hours of labor, one said it would be a whole day, one said 5 hours of labor.. and at that.. it was 375 going rate. i still have to look at a few other shops to see if i can get this kind of work done, however as far as dyno's.. thats the going rate. there are NO other shops that do dyno's around here for the public. trust me, after phone tagging around, i've found one shop fully capable of doing everything that i needed. if you know any mechs that do this kinda work in the tri-state area (pa, nj, de.. or even md) let me know. i still haven't given up on the idea, though cost is a big factor, i will definately have to look around more than i have.
peace

If you can change the timming belt yourself than swap the cams yourself it's 30 minutes more work. I did it on the BP engine myself it took me less than 3 hours to remove/install the p&p head, but the engine was out of the car since I was swaping the DOHC BP engine into my 92 323LX. The engine swap alone took me about 8 hours, not bad for a first time.

[Kevin]

eh, thats a legitamet question.. personally, my car's an automatic.. so i couldn't care less. most likely they will end up driving it... who knows. as far as the dyno runs.. no one around here does it cheaply like i said. and as far as doing the work myself, i'm never going to learn anything until i can do the work myself, so i MAY just take on this myself.. and there is a guy locally that does some engine work on the side.. i may be able to make out on that end. i'm not entirely sure how i want to go about this, but only a little more research may tell.
peace

[Kevin]

i stopped short of wanting to do this, and figured with current expenses and christmas, 1000 bucks would take me roughly into march to save everything up to afford this upgrade... my decision is to not go through with my cam shaft dreams. i'm more educated than before, and i'd be willing to answer any and all questions as far as cam shafts are concerned to the best of my ability. well, needless to say, i'm going to have a dyno done reguardless with in the next few months that you guys can look forward to once i gather the money together (basically 2 inch cat back w/ silencer and 3 inch ebay intake with conefilter & adapter). good luck to those who take on this task of cam shafts. bottom line, speed costs money.. so no dough, no go.
peace

[zorlac7]

Originally posted by mike323

1) 0 I, 0 E
2)+3 I, 0 E
3)+3 I, +3 E
4) +3 I, -3 E
5) - 3 I, 0 E

+ = advance
- = retard
I = intake cam
E = exhaust cam[/B]

which is the range of commonly & useful variation degrees ??

until now, i don't hear more than +/- 5º.

[mike323]

Originally posted by zorlac7
which is the range of commonly & useful variation degrees ??

until now, i don't hear more than +/- 5º.

You start off with 3 degrees and then you take things from there. On the miata we ended up with +2 I and -1E as the optimum for the modifications the car had. That yielded us with 132whp and 112lb-ft.

[zorlac7]

but that change with every pair of cams.

u don't have something to determine the exact grade where have to be ??

explain me in words of cam regrinder, the thing about your "+2 on Intake & -1 on Exhaust".

[mike323]

Originally posted by zorlac7
but that change with every pair of cams.

u don't have something to determine the exact grade where have to be ??

explain me in words of cam regrinder, the thing about your "+2 on Intake & -1 on Exhaust".

I'm not sure I understand your question.

When you regrind the cam you don't affect the centerline, to do so you need adjustable cam gears. You can change the centerline by a 2-3 degrees max but that reduuces your base circle even more, hence I never do it on DOHC engine since you can get adjustable cam gears and tune it as you desire.

+2 I means that we advance intake timming by 2 degrees and -1 E means that we retarded exhaust timming by 1 degree.

[zorlac7]

Originally posted by mike323 +2 I means that we advance intake timming by 2 degrees and -1 E means that we retarded exhaust timming by 1 degree. [/B]

duhhhhhhhhhhhh..i know.

that i say is..why -1º and not -3º or 5º or other grade ??

[Gro Harlem]

Yo mike323...here are the specs I was promising you..i finally found my 91 FSM

Here is the camshaft specs for:

1.6 B6 SOHC 8v engine in the 90-94 323:

Lobe height: mm (in)

INTAKE:
standard 36.451 (1.4351)
wear limit: 36.251 (1.4272)
EXHAUST:
standard 36.451 (1.4351)
wear limit: 36.251 (1.4272)

Journal diameter: mm (in)
Front:
43.440-43.465 (1.7102-1.7112)
Center:
43.440-43.465 (1.7102-1.7112)
Rear:
43.440-43.465 (1.7102-1.7112)

Valve timing:
INTAKE:
Open BTDC: 14
Close ABDC: 50
EXHAUST:
Open BBDC: 52
Close: ATDC: 12

1.8 SOHC 16v B8-ME in 90-94 Protege DX:

Lobe height: mm (in)
INTAKE:
Standard: 35.993 (1.4170)
Wear limit: 35.793 (1.4092)
EXHAUST:
Standard: 36.273 (1.4281)
Wear limit: 36.073 (1.4202)

Journal Diameter:
No.1 & No.5: 43.440-43.460 (1.7102-1.7110)
No.2 & No.4: 43.425-43.450 (1.7096-1.7106)
No.3: 43.410-43.435 (1.7091-1.7100)

Valve Timing:
INTAKE:
Open BTDC: 2
Close ABDC: 50
EXHAUST:
Open BBDC: 55
Close ATDC: 8

I'm not sure what the hell that No1-No5 **** means on the B8-ME camshaft instead of saying "front center and rear" it says those instead

[mike323]

Originally posted by zorlac7
duhhhhhhhhhhhh..i know.

that i say is..why -1º and not -3º or 5º or other grade ??

Keep your smart ass remarks to yourself, stop degrading your intelligence with foolish quotes.

Look at a dyno plot and then you can come up with similar conclusions as myself. You always go after the curve with the most area under the curve between 4000-7200rpms, provided you get descent idle around 750-800rpms and descent low end power below 4000rpms.

[mike323]

Originally posted by Gro Harlem

Here is the camshaft specs for:

1.6 B6 SOHC 8v engine in the 90-94 323:

Lobe height: mm (in)

INTAKE:
standard 36.451 (1.4351)
wear limit: 36.251 (1.4272)
EXHAUST:
standard 36.451 (1.4351)
wear limit: 36.251 (1.4272)

Journal diameter: mm (in)
Front:
43.440-43.465 (1.7102-1.7112)
Center:
43.440-43.465 (1.7102-1.7112)
Rear:
43.440-43.465 (1.7102-1.7112)

Valve timing:
INTAKE:
Open BTDC: 14
Close ABDC: 50
EXHAUST:
Open BBDC: 52
Close: ATDC: 12

1.8 SOHC 16v B8-ME in 90-94 Protege DX:

Lobe height: mm (in)
INTAKE:
Standard: 35.993 (1.4170)
Wear limit: 35.793 (1.4092)
EXHAUST:
Standard: 36.273 (1.4281)
Wear limit: 36.073 (1.4202)

Journal Diameter:
No.1 & No.5: 43.440-43.460 (1.7102-1.7110)
No.2 & No.4: 43.425-43.450 (1.7096-1.7106)
No.3: 43.410-43.435 (1.7091-1.7100)

Valve Timing:
INTAKE:
Open BTDC: 2
Close ABDC: 50
EXHAUST:
Open BBDC: 55
Close ATDC: 8

I'm not sure what the hell that No1-No5 **** means on the B8-ME camshaft instead of saying "front center and rear" it says those instead

Lobe height is that base circle + lift?

Journal diameters is where the camshaft gets to sit on the head, this has nothing to do with the cam lobe profile. The reason why the 1.8 SOHC (#1, 2, 3, 4, 5) is because 5 bearing caps are used to hold the camshaft on the head, one in between each combustion chamber.

Based on the duration data there's room to improve the 1.8L SOHC camshaft since the intake cam only has 50+2+180 (132 degrees of duration). I'm certain we can get at least 8-10whp more on this camshaft and still make it idle at 750rpms.

[racerboygtx]

ok yall heres a problem that even amazes me, im driving my car (1993 mazda protege lx 1.8 DOHC)(5Spd)). now i while i was driving the car popped of a cam gear, yes it snapped the bolt a retaining pin. well got the car home pulled the head, no bent valves, head is atraight and no cracks. the number 1 exhaust journal though is screwed and well actually to say its got real rough spots. i need a wayto repair this in my own shop the help would be greatly appreciated, i wiil have this head back in my car, ohh did a port and polish while head was off enlarged all oil passages and colant ports aswell.

[therieldeal]

as far as i know if the cam bearing surfaces are messed up... the head is junk. why did you enlarge the oil and coolant passages? i wonder if some shavings were stuck down in there, causing a bunch of friction and the damage you described.

-jon

[racerboygtx]

i enlarged the ports after the camgear popped off. i have a feeling the head is salvageable, just got to resurface the bearing, some how, if this works ill post a step by step write up.

[Shades]

It's gotta get line bored and then hopefully fit aftermarket bearings in there if there is a size that'll fit... that's the only way to fix that or else find a new head.

Don't know why you'd enlarge the coolant cause the head gasket limits what gets to it...

... and enlarging the oil passages is just rediculous.

You might of wanted to start your own thread instead of bring up an old one from 2003.