Ignition Module Failure....???"

[Peer81]

Are you looking at the normal XE series or the special computer XE series? I think the computer XE series has little overlap and you have a normal idle.

Greetings Peter

 

[LannyL81]

Gerry,
With this cam what does the numbers come out to be?
exhaust opens at 44 BBDC, intake closes 29 ABDC
112 LSA, 107 intake centerline
70 cc head, 0.038 gasket thickness, 4.190 gasket bore

Everything else is the same.

Thanks much...

 

[GerryLP]

Gerry,
With this cam what does the numbers come out to be?
exhaust opens at 44 BBDC, intake closes 29 ABDC
112 LSA, 107 intake centerline
70 cc head, 0.038 gasket thickness, 4.190 gasket bore

Everything else is the same.

Thanks much...

Here you go, Lanny. Check the intake valve closing event for accuracy. Is that at 0.050" or 0.006"? Also, notice the quench...that gasket may eventually cause the piston to hit the head chamber at some point...:ugh

 

[Peer81]

Also look for a shop that sells racing fuel. A DR 9.4 is to high IMHO.

Greetings Peter

 

[LannyL81]

Gerry,
The cam numbers I last sent you are at 0.050...not seat-to-seat or 0.006. I can convert the intake closing to 0.006" if necessary.

Peter: Ah...yeah....that would require some racing fuel or else I would be buying fuel at the airport.....not what I want to do.

I have been using another DCR calculator and it seems that I would be much better off getting some 76cc iron heads based upon DCR numbers. If I get the cam with the numbers above, and the 70cc heads I get a DCR of 7.77 which I may be okay with the aluminum heads.

I took the lifters out today and noticed that #4 exhaust lifer had some wear on the bottom. So my cam may have a wiped lobe due to the valve not moving and putting a large force load onto the lobe. I have yet to pull the cam out...that will be one evening this week.

 

[GerryLP]

Either way. The program has a calculation feature from 0.050" values, but it requires the lobe lift, and the duration at 0.050"...

 

[Peer81]

I always use this one:
http://www.projectpontiac.com/ppsite/compression-ratio-calculator

If I remember correctly your DCR with iron heads is max around 8 to 8.25. I hear with alu you can get it one point higher but I can't verify that. I bought some 72 dart iron eagles.

Greetings Peter

 

[LannyL81]

Either way. The program has a calculation feature from 0.050" values, but it requires the lobe lift, and the duration at 0.050"...

Duration at 0.050 is 204/214, lift is 280/295 (I think...I may have written that down wrong).

 

[GerryLP]

Duration at 0.050 is 204/214, lift is 280/295 (I think...I may have written that down wrong).

What is the cam grind number or advertised model?

 

[LannyL81]

Thecam I was thinking about getting was the Melling MTC-1 or Edelbrock 2102...same cam.

However after more reading and discussing....think the Voodoo 60101 cam would be a better choice due the higher lift it offers that the 67039 heads are capable of.

Oh and the numbers I posted above were correct for the MTC-1 cam.

If you have a chance, could you see what you get for the Voodoo cam?

No hurry though...when you get a chance.

Thanks Gerry.

Oh and anyway interested in a set of 882 heads? Needs one new exhaust valve...possibly guide...

Lanny

 

[GerryLP]

Edelbrock 1202 cam

Here is the data with the Edelbrock cam data input

 

[GerryLP]

Lunati Voodoo 60101 cam

And here is the data with the Lunati Voodoo 60101 cam

 

[Tim81]

Now that looks like a nice set-up...IMHO

And here is the data with the Lunati Voodoo 60101 cam

 

[LannyL81]

The VooDoo cam looks to be the way to go....and a bit thicker head gasket....the 0.038 is matched to the Edelbrock heads and intake...but is just too thin for my application. Will have to get a FelPro head, intake, exhaust gasket set. I also need a front cover and probalby oil pan if I tear mine getting it off.

Okay, now I need suggestions on what to use to clean the carbor off the top of the pistons...with them in the block.

Thanks for the info Gerry. I will send you the 882 heads....:L

Lanny

 

[GerryLP]

The VooDoo cam looks to be the way to go....and a bit thicker head gasket....the 0.038 is matched to the Edelbrock heads and intake...but is just too thin for my application. Will have to get a FelPro head, intake, exhaust gasket set. I also need a front cover and probalby oil pan if I tear mine ....Lanny

Lanny, a good self-imposed insurance policy against problems later on is to pay close attention to the spring height and load required for the Voodoo cam. Since you are replacing your cylinder heads, take the time to contact Lunati by email, and ask them if your heads' spring/loads combinations are suitable for the 60101 cam and will not void the warraty on the cam. If the cam goes flat, the cam companies tend to blame the springs and associated loads used. Also, if you notice in the cam card for the Voodoo, the centerline of 108 makes the cam and "advanced" cam, which means that when installed straight up, it is already advanced by about 2 degrees. My software tells me to enter the valve timing with all the advance in the cam, but I am not sure that if and when Lunati lists the intake valve closing timing of 34.5 degrees, they are already including the 2 degrees advance it has or if is not included, but the DCR does not change a whole lot IAW with the software, and since you are using aluminum heads, you'll likely to not experience any power loss on your set up, IMHO.

Also, as you noticed in the software data numbers, I bumped up the gasket thickness to keep your engine away from valves and pistons colliding. These critical dimensions are not an exact science for you and I, and there are variables that could manifest themselves when the engine is above 3,000 rpm such as valve floating, component velocities, and weightthrown about that tend to slightly alter how components come close to each other.

Since I bought my first one-piece oil pan Fel Pro gasket, I have not gone back to anything else. Lookup in Chevyhiperformance.com how to notch the timing chain cover, so that it can be removed without having to lower the oil pan.

 

[LannyL81]

Gerry,
I wll heed your advice and double-check the spring height and VooDoo cam requirements.
I would rather use a 0.041 gasket as the quench is better than with the 0.051 gasket....but need to double-check the piston to valve clearance.

With regards to the article on ChevyHighPerformance about one piece oil pan gaskets and notching the front cover.....could you direct me more to the article....I could not find it.

Thanks again for the help.

 

[GerryLP]

It should be in the following link, but I can't see where the story continues to page 2...

Engine Assembly Tricks & Tips


More on cam applications and tuning

Hard-core Cam Tech With the Experts From COMP Cams and Isky Racing

 

[LannyL81]

Rockers??

Gerry or anyone....do you know if full roller rockers will fit under the stock valve covers?
Since I think I need to replace my 1.6 roller tip rockers with 1.5/1.52 I was wondering about going to full rollers...but do not know if they will fit under the stock valve covers or not.

Any experience with Summit or ProForm brands? The Comp or Crane are just too high $$ for me.

 

[Tim81]

Gerry or anyone....do you know if full roller rockers will fit under the stock valve covers?
Since I think I need to replace my 1.6 roller tip rockers with 1.5/1.52 I was wondering about going to full rollers...but do not know if they will fit under the stock valve covers or not.

Any experience with Summit or ProForm brands? The Comp or Crane are just too high $$ for me.

Lanny, Its my understanding that because of the baffle inside the covers that full roller rockers will not fit in a stock cover. You may have to go with the tall style covers which can cause fitment problems with your alt and a/c set-up. Tim

 

[Peer81]

May I ask why 1.6 rockers will not work anymore?

Greetings Peter