Found a Comp Cam for sale with the following specs:
220/218 @ .050"
.581/.562
111 lsa
Do you think that this would be a good cam for a lq4 in a 2007 Classic 2500hd 4 door 4x4? Oh and it is lifted 6" with 35" tires. I allready have 4.88's too. I will be putting on some lt's and some 243 heads on at the same time. Would a torque converter be needed with this cam? What characteristics do you think this cam will have in my setup? I'm thinking this will be a good mid to upper rpm cam with a pretty lopey idle. I just don't know what it will do to the bottom end. Any help you guys can give me would be great.

 

MOST "Truck" cams run a 115ish LSA, to essentially reduce overlap. It does not have large durations but the LSA has me thinking this is more for a lighter vehicle.

I just used TR as an example. But summit and bunch of other sponsors seem to be in the same range. Maybe a cam guru/sponsor can weigh in.

http://www.thunderracing.com/shop-by...ain/Camshafts/

4.88's are nice for the rear but it does knock down the TQ multiplcation and effectivly what the rearend is ratioed for the final drive so you need to see what that would be compared to lets say a 26-28" tall tire which is what most F bodies run.

 

From my understanding the the tighter the lsa the sooner the power will come on and the sooner it will sign off, because of the valves being opened for a shorter amount of time and being closed longer. That is until you start adding a lot of duration into the mix. Then you get overlap and the idle and driveability go down. I don't mind a lopey idle. Actually I would kind of like it to lope. I just don't want to loose ANY bottom end power. Its hard enough to get 7000lbs moving as it is. Lol. I know the higher compression gained from the 243's and thinner hg's will help bottom end. So this might compensate for the cam. The lt's shouldn't hurt anything either. Correct me if my thinking is wrong. Thanks again.

 

It should actually work pretty good...if your truck is an auto is look for something around a 2,600-2,800 stall

His ratio with those tires should work out to somewhere around 3.90's compared to stock f-body size tires

 

Well I just paid for it. Brand new cam shipped for $220. Should be here by next week. I got such a good deal on it, if it doesn't work out it won't be that big of a deal. Time to order some head gaskets, push rods and valve springs. I will see how the truck acts and where the power comes on at, before I throw money at a torque converter.