[DarkoStoj]

First here are the specs on the motor

400 .040 over
8.7:1 compression
#62 heads, filled crossover, light port work
long 4tube headers & flowmaster exaust
RAIV cam
1.65 roller rockers
performer RPM intake
speed demon 750 dp (or holley 750 vac secondary)
MSD dist
th350 with 3k stall
3.73 gear

I bought the car and the motor was "rebuilt" with 500 miles but it was an absolute disaster and I had to rebuild the motor again. I'm reusing some of the parts since they have so few miles on them. The first picture is of how the camshaft was originally installed.

Was it installed straight up, advanced, or retarded? Cause I have no idea



Here is a better picture of the gear itself. I have no idea how to install this thing, or what the markings on the crank gear mean.


Should I install the crank straight up or 4* advanced?

[mchell]

not a real good pic......it looks like the cam is indeed installed "straight up" and you are at TDC on #6 cylinder........thats if your line from the cam dot is drawn to the actual dot on the crank......hard to see the dot on the crank...

Get a degree wheel to properly degree the cam to the cam manufacturer's specs.......if its an unknown cam, you could install it straight up and hope its close......many cams come ground 4 degree's advanced.....you are guessing if you don't have the cam specs.......it may run great it may not...

[71 Ventura II]

Agreed, it looks like the engine in the picture should be sitting at TDC #6.

The indicators are: Your timing "dots" are facing or (crank at 12 o'clock and cam at 6 o'clock) Also, the crankshaft key way is close to the 2 o'clock position.

When the engine is at TDC #1 your "dots" will be up. Crank at 12 o'clock and cam at 12 o'clock. The key way on the crank if degreed "straight up" would be close to the 2 o'clock position.

Agreed, the only way to guarantee the engine will perform like you want is to beg, borrow, or buy a degree kit to verify the installation. Good luck, JD

[DarkoStoj]

oh man I am so lost. Can you guys start from the beginning and explain how you know its at TDC on #6 and installed straight up? I was under the impression that you line up the dot on the crank gear with the dot on the cam gear to get straight up. I have 2 dots and 2 + marks on the timing gear that confuse me.

Also I am familiar with degreeing the cam, but how am I supposed to know what the correct cam timing events are w/o a timing card?

[mchell]

this may help......there is usually only one dot on the cam sprocket and one dot on the crank sprocket......shown in the pic is TDC on #1..........without knowing the cam specs you will have to punt.....you could pull the cam and see if yu can identify the cam manufacturer ..... then get specs

[mchell]

again....

[71 Ventura II]

The more I look at the picture the more it looks like the crank keyway is pointing closer to 1 o'clock. Man it's hard to see.

First and foremost you need to verify how many markings are on your crank gear. I "think" I see a *(star), a rectangle, and one more I can't see.

We need to verify the markings to make sure which symbol is straight up. If your not familiar with Pontiacs it's easy to get confused. A traditional Pontiac V8 timed at TDC #1, no additional advance or retard of the cam, will have both "dots" at 12 o'clock. AT THIS TIME, if you rotate the engine 180 degrees it will then be at TDC #6 and the "dots" would be facing each other.(Facing crank 12 o'clock & cam at 6 o'clock)

Keep in mind we aren't able to see if the correct mark is being used on the crank gear. But by observing the "perceived" timing "dots", their orientation, and crankshaft key way we can guess.

It's possible you may or may not be using the correct mark on the crank gear. JD

[Billy177]

It looks like it is installed advanced because the + park is lined up with the dot but it is hard to tell from the picture

[screamingchief]

Well,it's a crappy pic,sure,but a few things appear to be obvious.

First off,it's a single keyway double roller timing chain set,so the only way it could be installed advanced/retarded in any way,is if offset keyways are being used,or it was somehow installed incorrectly,or manufactured incorrectly.

Next up,I gotta mention that with all the attention being given to the "dots" and gear alignment,it seems that many folks here have missed the fact that something looks amiss with regards to the fuel pump eccentric and how it is assembled,the bolt/washer does'nt appear centered in the eccentric properly,and looks to be "off",so I gotta advise that be given due attention and checked out carefully.

I would advise removing the cam bolt/washer/eccentric assembly and checking it out fully.

This will also allow you to get us a pic without the eccentric on there,which will give us a whole lot better idea what is going on,as we'll be able to see the keyway in the cam as well.

If all appears to be in order,reassemble the eccentric assembly and rest assured it's all together correctly.

And last but not least,I gotta advise you to check and be sure the lower crank gear is'nt on backwards and your real timing "dot" is'nt actually on the backside of the gear.

Because those "marks" in the pic of your crank gear dont look much to me like they're really meant for this purpose.

Dont laugh,,,have seen this happen a few times...

If there are'nt any marks on the backside,most folks will catch this,but if a fella finds a mark that seems close enough to "work",they'll often just assume that's how it's supposed to go together,and not give it a second thought.

This is a longshot of course,but never hurts to be thorough.

Obviously degreeing the cam will catch most of these kinds of mistakes if done properly,and it is clearly the "correct" way to do this.

Just a few suggestions to look into,I'm sure all here will help you get this figured out and put together right.

Bret.

[71 Ventura II]

Originally Posted by DarkoStoj

First here are the specs on the motor

400 .040 over
8.7:1 compression
#62 heads, filled crossover, light port work
long 4tube headers & flowmaster exaust
RAIV cam
1.65 roller rockers
performer RPM intake
speed demon 750 dp (or holley 750 vac secondary)
MSD dist
th350 with 3k stall
3.73 gear

I bought the car and the motor was "rebuilt" with 500 miles but it was an absolute disaster and I had to rebuild the motor again. I'm reusing some of the parts since they have so few miles on them. The first picture is of how the camshaft was originally installed.

Was it installed straight up, advanced, or retarded? Cause I have no idea



Here is a better picture of the gear itself. I have no idea how to install this thing, or what the markings on the crank gear mean.


Should I install the crank straight up or 4* advanced?

Now that I've focused better I can see the three symbols on the crank gear. They are - rectangle +. It does appear the camshaft is installed using the "advanced" position on the gear. You can clearly see the -(negative or retarded) symbol and the + (positive or advanced) symbol. JD

[BILTIT]

Not sure how you are getting 8.7:1 comp. (dished pistons?) My calc shows closer to 10.25:1.

http://www.sdperformance.com/calc_cr...der=8&check2=1

[screamingchief]

I only see one keyway on that crank gear,so anybody feel free to please explain how this could be determined to be installed advanced...

That's how this works,the crank gear would have to use multiple keyways to be installed advanced,or retarded,this is done by utillizing differing relationships between the keyways and the timing marks,this is how you make the advance/straight up/retard changes.

Without a multi-key crank gear the only other way to correctly advance or retard a cam is by using an offset crank or cam key,and in that situation,those marks are useless.

Those marks amount to gibberish without a way to put them into context.
(ie. known good instructions from the chainset manufacturer,or positive determination via degreeing)

I see a - mark,an R mark,and a + mark (in that order,clockwise from left to right) of course that makes zero sense,the R is in the middle where the 0 mark should be,then the - would mean retard,and the + would mean advanced,but again with only one keyway visible here,that all is likely moot and meaningless.

There is also some other markings at the 2-3 O'clock position,but that is too blurry to make out.

And again I'll point out the fact that the eccentric is installed 100% wrong!

This appears to be the type of eccentric that is supposed to fit it's alignment "tang" into the cam keyway slot in the timing gear,but if you look close you'll see it's installed in the hole in the cam gear intended for the other style eccentric,this is obvious because the cam bolt and washer are'nt centered in the eccentric properly.

This also means that very likely the cam is'nt pulled all the way into the cam gear properly,which in turn means more than likely there is excessive cam endplay,and the chain alignment could be off as well,this is a very bad situation,as it also can affect lobe wear and timing chain life significantly.

Cam endplay should be .003"-.007" appx.

This is why I advised pulling this apart,and in the process checking to see if the crank gear is on correctly and not on backwards,with the correct 0 (dot) mark on the backside of the crank gear.

I hate to say this,and hopefully it is'nt taken as anything other than an attempt to help here,but it looks like whomever installed this timing chain set had no clue what they were doing,so ask me all bets are off as to what is going on here,tear it all off and start from scratch,and degree this properly,that's my advice,take it or leave it.

Look at the big picture,beyond just the marks on the gears...

Bret.

[Murf]

Maybe someone who didn't know what he was doing thought if he lined up the cam dot with the + it was advanced. I don't understand why there are + and - marks on a gear with a single keyway either. I think the chain shoud be removed and the crank gear rotated until the dots line up but the bottom gear seems strange to me.
Murf

[71 Ventura II]

Screaming Chief: I hope you go back and read your post so you see how "wrong" your statements are. I'm not saying your 100% off but closer to 87%.

YES, you can degree a cam using a "single" key-way in the crank gear. How do you think people setup camshafts before the aftermarket started "helping" the average Joe by creating an easier way.

Just for an example: Look at the majority of the "Gear-drive" sets on the market. Most if not all of them come with "one" a single key-way on the crank gear. People have been degreeing cams with gear-drives for decades.

If we look at the crank gear used in a timing set and cut (8) key ways in it. Now ask yourself this question, "What happens when I use a key-way in a different location than stock?". The crank will turn a "given" amount to allow a different "tooth" of the crank-gear to be at the 12 o'clock position. We haven't cut any new key-ways into the crank, that variable, as always, stays consistent. See?

So yes, you can degree a cam "straight up", advanced, or "retarded" using a gear with a single key-way. In the efforts to help clarify your knowledge of "degreeing" a camshaft I hope you research this topic more before you offer help to others. Sometimes, even the most "honest" effort to help people can actually cause more damage than good when the help is misguided. JD

[DarkoStoj]

The guy who put this motor together had no idea what he was doing. I mean he actually installed the main bearings BACKWARDS, and there was a thick film of silicone over the oil pump pickup screen.

Anyway I installed the crank and cam gear back to how he originally had them and snapped a pic.




also on the crank gear, there are 2 dots, 2 -signs, and 2 + signs.

[DarkoStoj]

Originally Posted by BILTIT

Not sure how you are getting 8.7:1 comp. (dished pistons?) My calc shows closer to 10.25:1.

http://www.sdperformance.com/calc_cr...der=8&check2=1

i have -16cc pistons

[screamingchief]

71 ventura II:
Screaming Chief: I hope you go back and read your post so you see how "wrong" your statements are. I'm not saying your 100% off but closer to 87%.

YES, you can degree a cam using a "single" key-way in the crank gear. How do you think people setup camshafts before the aftermarket started "helping" the average Joe by creating an easier way.

Just for an example: Look at the majority of the "Gear-drive" sets on the market. Most if not all of them come with "one" a single key-way on the crank gear. People have been degreeing cams with gear-drives for decades.

If we look at the crank gear used in a timing set and cut (8) key ways in it. Now ask yourself this question, "What happens when I use a key-way in a different location than stock?". The crank will turn a "given" amount to allow a different "tooth" of the crank-gear to be at the 12 o'clock position. We haven't cut any new key-ways into the crank, that variable, as always, stays consistent. See?

So yes, you can degree a cam "straight up", advanced, or "retarded" using a gear with a single key-way. In the efforts to help clarify your knowledge of "degreeing" a camshaft I hope you research this topic more before you offer help to others. Sometimes, even the most "honest" effort to help people can actually cause more damage than good when the help is misguided.

I've been thru this dreck with you before 71 ventura II,your the one that has a hard time reading and understanding others comments.

Reread my posts,I never stated what your implying I said,I said IF there is only one keyway,there is no way other than using offset keys to accurately advance or retard the cam,unless a person wants to take a crapshoot and try installing the gear a tooth off on the chain,which would in essence be installing it wrong!

SO let's break down your whining BS comments:

YES, you can degree a cam using a "single" key-way in the crank gear. How do you think people setup camshafts before the aftermarket started "helping" the average Joe by creating an easier way.

Again,when that was the case,they used offset cam/crank keys on pontiacs,,,which I VERY CLEARLY STATED,,,next...

Just for an example: Look at the majority of the "Gear-drive" sets on the market. Most if not all of them come with "one" a single key-way on the crank gear. People have been degreeing cams with gear-drives for decades.

See above...

If we look at the crank gear used in a timing set and cut (8) key ways in it. Now ask yourself this question, "What happens when I use a key-way in a different location than stock?". The crank will turn a "given" amount to allow a different "tooth" of the crank-gear to be at the 12 o'clock position. We haven't cut any new key-ways into the crank, that variable, as always, stays consistent. See?

And again,go back and reread my comments,without the reference marks being reliable,known,and VISIBLE,how would you have a clue where it is installed unless you degree the thing to find out???

There was NO WAY in the first pic to make a reliable assumption of where the cam was installed!

You could'nt even see the other keyways for christsakes!!!

So beyond making a lucky guess,there was little point to try and say what was going on.

So yes, you can degree a cam "straight up", advanced, or "retarded" using a gear with a single key-way.

Please,do explain to us how YOU would do that,with a single keyway crank gear,and without using any offset keys.
(as I've already pointed out clearly are used for this,many times previously here)

In the efforts to help clarify your knowledge of "degreeing" a camshaft I hope you research this topic more before you offer help to others.

How many have you degreed mister know-it-all,I gotta borrow my relatives degree kit to do degree his own...

I own my own degree equipment,have for years,and done this dozens of times,and I fully understand the in's and out's,so do tell,what makes you the expert,I mean the last time we sparred over this you were asking how to eyeball a cam degree,I mean really,,,give me a break...

My degreeing knowledge is just fine,have done three cam degrees in the last few months.

The first pic sucked,it's obvious now that this indeed has a three key crank gear,but you could'nt even tell that in the first pic!

So yeah,sure I was wrong about that one thing,,,BFD...

Also the fact remains the eccentric was installed wrong,and ALL here missed that!

And that was obvious,even with the $#!t pic...

87% off my a$$,maybe 5-10% off.

I did'nt assume jack,reread my comments,they're very carefully worded and make clear nothing could be assumed due to the poor picture quality.

Get over yourself 71 ventura II.

[screamingchief]

also on the crank gear, there are 2 dots, 2 -signs, and 2 + signs.

That makes sense,the dots indicate straight up (no advance/retard),one to indicate the keyway,one to use for aligning to the cam gear,so follow that logic and the same is true for + (advanced),and - (retard).

To install it advanced/retarded,pic the keyway marked with either symbol and use the corresponding mark on the gear to line up with the cam gear.

The pic looks to be installed advanced TDC #1 cylinder right now,but still cant see the marks on the gear very well,too small,but I can see that the - mark is counter-clockwise to the current alingment marks,so the marks being used must be the + symbols.

Much better pic though,and be sure to get the eccentric on right this time,and please check your cam endplay.

HTH.
Bret.

[DarkoStoj]

Originally Posted by screamingchief

That makes sense,the dots indicate straight up (no advance/retard),one to indicate the keyway,one to use for aligning to the cam gear,so follow that logic and the same is true for + (advanced),and - (retard).

To install it advanced/retarded,pic the keyway marked with either symbol and use the corresponding mark on the gear to line up with the cam gear.

The pic looks to be installed straight up TDC #1 cylinder right now,but still cant see the marks on the gear very well,too small.

Much better pic though,and be sure to get the eccentric on right this time,and please check your cam endplay.

HTH.
Bret.

alright I understand how they should be installed to advance/retard etc. It looks like the cam was installed advanced with the + lined up with the dot on the cam gear set at 12 o'clock.

Does anybody reccomend whether I should install the camshaft advanced or retarded or straight up? how would I be able to verify how it needs to be installed by degreeing w/o a cam card?

[screamingchief]

In a low compression 400,install it 4 degrees advanced IMO.