LS1 cam install experts,

I'm back to my cam install....trying to get my "bearings" straight ...I found TDC, ICL is 114, I've got the cam sprocket at "6 O'Clock" and the adjustable crank/sprkt in the 0 straight up position. If I want to advance the cam 4%..(here's where I start to get fuzzy...) do I move the cam sprocket forward(clockwise) and re-install the timing chain?...or do I just move the crank shaft/key counter-clockwise...and re-install the chain?

stroker2112

 

I wouldnt worry about advancing it. Just line it up dot to dot.

 

I think you mean 4*. Anyways, whats the specs of the cam?

 

..I'm thinking it should be done....after advancing 4 deg the valve events are:

10 BTDC IVO
50 ABDC IVC
52 BBDC EVO
4 ATDC EVC

110 ICL , 14deg overlap
...its a 240/244 in a NA 408 ...

 

Yes turn the crank sprocket clockwise 4 degrees. Usually 4 degrees is 2 keyways in the clockwise direction.

 

GreatwhiteSS,

If I advance the crank & keyed sprkt clockwise ...then doesn't this cause the intake valve to open later on the intake stroke?....

So, to make the intake valve open earlier (from 6* BTDC to 10* BTDC)...I need to advance the cam in relation to the crank....right? So would'nt I need to move the crank key/srpkt counter clockwise?....

This is where I get fuzzy.....

stroker2112

 

is the intake valve opening/closing points happening at there specifed degrees from what the cam card says?

 

Yes,

The cam is on a 114LSA+0 grind....it specs out on the degree wheel...so I am wanting to advance it 4*....just having some confusion on what part to advance....cam sprkt or crank sprkt...and if its the crank sprkt...which way?.....clockwise or counter-clockwise...thanks in advance...what I think is diff then what some people have posted...

 

Without seeing what crank sprocket you have, if it is a multi-keyway, then there are advance and retard marks on the crank sprocket. Typically the 4 deg. advanced mark is a triangle. Or it will actually say "+4" directly over one of the sprocket keyways. If that is the case, then install the sprocket with the advance mark onto the crank key, then just time the cam sprocket with the dot to the new TDC mark on the crank. So what you would have is a triangle or +4 lined up with the only dot on the cam sprocket at 6 or 12 o'clock.

 

who's timing set you using?

 

SLP.....I moved the crank sprkt counter-clockwise (from 2:00 O'Clock to 10:00 O'clock....2 keys ) last night....and will test ICL again after all the kids in my house leave me alone....

 

does`nt the cam already have some advance ground into it?

 

No advance...card says it has a 114* ICL. I just spent last 3 hrs trying to dial this in...I think I'm pretty close to my goals...within 1* of my IVO (10*) and an approx 112* (wanted 110*) ICL. After doing this for several hrs with varying results and with the equipment I have...I think I'll settle for what I got....then again, tomorrows another day....

Stroker2112

 

So did it run better doing what you did?

 

...I haven't put the engine back together yet (heads, valetrain ,intake), it's on a stand....I'll probably go back to check my work in an effort to get it closer to 110LSA later this week.....I'll still need to find a tuner after I get everything put back together...

 

OK, so I've got everything buttoned back up.....took her for a test drive and it appears to have some new found power, especially in the mid-to-high rpm range (swapped in a 240/244). Now I just need to get it tuned ....pretty sure it's lean with all the new found "air" ...(bigger intake manifold, bigger cam)...it sounds mean as hell with just a little pedal/gas action....doesn't idle by itself yet....

stroker2112