cam in 2001 block??

[RAPTORFAN85]

Thanks dwg86,

Very extensive and helpfull reading.
Now I feel like im back at school again!!

[dwg86]

Have you already bought the 1.7 rockers? If you did,I think that is going to limit you on cam selectionfor a preground cam like comp, Lunati, or crane. Personally I would stay away from crane. Some of the newer Comp and Lunati VooDoo grinds have a pretty big lift with a 1.6 rocker.

[SilverXJ]

Personally I would stay away from crane. .

Especially since they are closed.

[RAPTORFAN85]

Have you already bought the 1.7 rockers? If you did,I think that is going to limit you on cam selectionfor a preground cam like comp, Lunati, or crane. Personally I would stay away from crane. Some of the newer Comp and Lunati VooDoo grinds have a pretty big lift with a 1.6 rocker.

Thats my problem. I have the 1.7 rockers now. I want to upgrade the cam because I know that I can get a good amount more power with a cam that breathes better. A custom grind kinda scares me. I wouldn't know were to begin and would prob. do more harm then good.
I just read threw all the links you posted and I feel like I'm getting a pretty good handle on it but im not sure,
If I use the 1.7 rockers I would have to go for a shorter lift cam like the comp 68-201-4 or 68-200-4 both of which have a LSA of 110.
Your saying that I might have vacuum probs. with them because the tight LSA causes more overlap.
My stock cam has 43* of overlap, but the 201-4 only has 40* and the 200-4 has 32*
Now, I'm not sure if the duration at .050 will affect the amount of vacuum lost as well.
Is it the combination of overlap and duration that affect the vacuum?
If so the 68-231-4 that silver is running has the same 32* overlap as the 68-200-4 and the 68-231-4 has 214 duration and the 68-200-4 has 206 duration.

The specs of the 200-4 and the 231-4 are almost the same except for lift(.433 vs .462int .485ex)
and exhaust duration (200-4 has [email protected]" and 231-4 has [email protected]")
So If I use my 1.7 rockers and the 200-4 it will bump the lift to .460 and the duration a little up from the 206. (I can't find anywhere that can tell me how much??)

seems like a good option to me. I don't need lots of top end to the cam and this to me seems like it would make good torque lower in the rpm's and thats what I'm looking for.

Does this seem like a viable option to you guys or am I way off the mark here??

[dwg86]

If you have a 110 lobe centerline and a duration [email protected]. You should be good. If you have a 110 centerline and say 220 dur @ .050 that might cause a problem (for the computer, not for a carbed car). I wish I could draw a picture on here. OK try this link http://www.chevyhiperformance.com/techa ... to_02.html This shows how the lobe separation and duration work together forming valve overlap. If you talk to a cam grinder they will lead you in the right direction. You may even figure out that the comp cam will work. I don't know how much valve overlap is good for low end torque and high vaccum.

I know the Mopar 30AB cam has a 108 lobe separation, 200 [email protected] and a valve lift of .453 with a 1.6 rocker. That would be 481 with a 1.7 rocker. The valve timing events @.006 are int open 26/intake close 54/ex valve open 62/ex valve close 18. That is with the cam 4 degree advance. I bought one of these cams and had it profiled at Reed. I sold it to mgardiner1 on this forum. He said he had 17 inches of vaccum at idle, and has no problem running on his computer controlled fuel injection. I think his jeep is a 1991???

So even tough the lobe separation was 108 the duration was short enough keeping the valve overlap from being excessive.

I hope I'm not confusing you. I am trying to help...really!

[RAPTORFAN85]

If you have a 110 lobe centerline and a duration [email protected]. You should be good. If you have a 110 centerline and say 220 dur @ .050 that might cause a problem (for the computer, not for a carbed car). I wish I could draw a picture on here. OK try this link http://www.chevyhiperformance.com/techa ... to_02.html This shows how the lobe separation and duration work together forming valve overlap. If you talk to a cam grinder they will lead you in the right direction. You may even figure out that the comp cam will work. I don't know how much valve overlap is good for low end torque and high vaccum.

I know the Mopar 30AB cam has a 108 lobe separation, 200 [email protected] and a valve lift of .453 with a 1.6 rocker. That would be 481 with a 1.7 rocker. The valve timing events @.006 are int open 26/intake close 54/ex valve open 62/ex valve close 18. That is with the cam 4 degree advance. I bought one of these cams and had it profiled at Reed. I sold it to mgardiner1 on this forum. He said he had 17 inches of vaccum at idle, and has no problem running on his computer controlled fuel injection. I think his jeep is a 1991???

So even tough the lobe separation was 108 the duration was short enough keeping the valve overlap from being excessive.

I hope I'm not confusing you. I am trying to help...really!

It is helping!! I am finaly starting to understand cam specs. It's kinda like speaking another language with cam specs...
The 30AB cam does have a narrow LSA of 108, but with the timing events of the valves it has 44 degrees of overlap which is only 1 degree over the stock cam, so with that and a not overly huge duration,it makes sense that it would work without problems.

So, with a wider LSA of 110 and less overlap (32 degrees) and a slightly higher duration at 206@ .050" I am pretty sure that it will work.

I will call a cam grinder just to verify that my redneck logic is in the ballpark.
What are my options and who have you talked to with success?? Engle, Racer Brown, Lunati??

[dwg86]

I agree, I think it would work.

The ones I enjoyed talking to the most(knowledge, didn't rush me off the phone, friendly) was #1)Jim from Racer Brown, #2)Reed Cams. Engle had good info but was kind of short on the phone. They may have been busy for all I know. They may want to know engine size, make sure they know it's a stroker, comp ratio, what type of vehicle, gear ratio, what it's used for(racing, daily driver etc.), auto or manual, computer controlled. Make sure you tell them you are using 1.7 roller rockers.

Let us know which cam you decide to use.

[RAPTORFAN85]

Well the stock cam is junk. The tips of the lobes are worn right off and the hard facing on the lifters is pitted and starting to come off. Kinda surprises me, the engine only had 42,xxx miles on it. This was before I knew about ZDDP and I was running off the shelf oil in the motor so that may have somthing to do with it. I am sure that this was also contributing to my lack of power towards the end before I pulled the cam. I will get some pics up when I get home tonight.
So, I guess that I won't be using the stock cam over. After talking to the Comp rep. I feel pretty confident that the 68-200-4 or the 68-201-4 will fit my needs very well. The 68-201-4 has a longer duration on a narrow LSA so I thought I might have problems with the computer. After talking to the comp rep he seemed to think that it wouldn't be a problem. He said that they advise against using them in a FI engine mostly to cover their a$$ but that it should work without problem. So I ordered the 68-201-4 with the nitride treatment (hopfully this will help the cam last a little longer) and a set of comps made in the USA lifters. Lift will be .475 with my rockers, 212 duration at .050 lift and an LSA of 110. This cam make lots of torque down low and Peak power should be just under the 68-231-4 that lots of people run and it should be right around 4500rpm.

This should make the stroker a true torque monster in the 2000-3750 rpm band.

I will let you know the results when I put the cam in

[dwg86]

Yep, should be a good torque cam.