Cakes

iTrader: (2)

I have been toying around the idea of adding a cam to my truck. Before I was primarily looking at off-the-shelf cams as I did not know much about valve events and the like. I am looking for a good cam with high low-end torque, good solid midrange, and decent pull up top to about 6K (+/-). My truck is 4WD so I do use it during the winter months. I never go off road and am just looking for a nice street truck. I do use my truck as a truck from time to time and it is my daily driver. I hardly if ever will take it to the track. I am just looking for a nice cam with some idle sound and great power when I want to have fun. I have the mods in my signature and will have electric fans (possibly crank pulley) and I am also planning on lowering the rear 2" with shackles and 2" up front with keys. I may also go to a shorter tire but only maybe (1) size down. I have come up with the following cams (both w/Comp XE lobes):

216/212 .561/.558 109-1

218/214 .563/.559 108-1

Both cams have IVC @ 38 ABDC and EVO @ 34 BBDC. They should both peak around 5600-5800 rpm or so and should have decent carry after peak due to the IVO=EVC. I think the low to mid range power should be great and it should pull to around 6100-6200 rpm. The "smaller" would obviously idle a bit better as it had -4* overlap as opposed to 0* overlap for the "larger" one. Any opinions/comments?

onebadrubi

Both of those should make good lowend power, I see you do have a small torque converter.

Out of curiosity why do they both have 4* splits? Just wondering. Im thinkin the 216/212 will be nice. maybe backing the intake side down a little bit.

Cakes

iTrader: (2)

I am not very well versed in camshaft design but I have been told and also read that having an IVO that is equal to EVC will promote good cary after peak. In this case the only way to get that ratio is to have the 4* split.

RandomHero

iTrader: (24)

run a 216/220 high lift. That would probably go well with your tt2600. You could even go as high as a tr220 which is a 220/220 .551/.551 on 112 lsa.

split duration cams work really well in our trucks.

rgvsierra

iTrader: (7)

those cams look good, the reverse split have so much better "get go" in the city imo, compared to the traditional split.

onebadrubi

I aggree!

Now I wouldnt go as big as random here says. Those cams will only benefit you in the 3500+rpms IMO. 2600 isnt enough converter IMO agian to run a 220 cam. Im likin a 214/212, will most likely come a hair bigger just cause cams are NEVER ground perfect or 214/210, XER lobe would be nice for the little bit added lift. Tuning is going to play a good part of how these cams actually perform since they are all very close in size.

RandomHero

iTrader: (24)

hmm, I guess different stroke for different folks but my 224 seems to come alive right at 3k rpms and I'm in a much heavier truck with a bigger cam. I'd only figure a 216/220 or a 220/220 would be perfect for what he has.

Mark Johnson

iTrader: (1)

At first I thought those were pretty big cams- but then I saw y'all we packin' 4.10 gears. I've kinda been thinkin' about a cam too add some punch down low, I'm running 3.73 gears and everything else stock. Was toying with a 200*/ 208* .502/ .502 112*LCA. Looking mostly for idel to around 4,000. These LSX motors are a whole new frontier..........

onebadrubi

in a 5.3l that is lookin for stock driveability I would think something like a 206/202 would add a little bit down low. Also you may want to start considering is this actually going to gain me enough to justify paying for the cam? I cant answer that question because I simply dont know the actual gains of a similiar cam but I do know that small will add a little bit of lope and keep torque off idle to 4500 atleast.

Cakes

iTrader: (2)

With a stock converter I think a cam that will enhance from idle or so to around 4500+ would be ideal as long as the cam can carry power into the upper RPM range. Since I have a 2600 stall I have in a way given up my low end to get it closer to peak torque faster so my "low end" starts at 2000 rpm or so. In my opinion if I could get a cam to enhance 2000-5000 with a peak torque of around 4250 and peak HP around 5600 and carry to 6000 I think it would match my setup pretty well. I am definately not looking for a race truck that spends most of its time at 4000+ rpm going down the track. If I had to estimate I would say I spend 90-95% of my driving time from idle to 4000 rpm. Very rarely do I go over so that is my reason for trying to enhance that rpm range. I keep thinking back to the late 1980's early 1990's L98 TPI 350 Camar/Firebird/Corvette engine. Everyone who drove/owned one claimed it was "Chevy's best truck engine never put into a truck". In a lot of ways I see some similarities in that engine and ours. Very long intake runners to promote torque output but unfortunately they narrowed the powerband down too much to make it a good performance engine. Going along those lines I think the long intake runner 5.3 intake manifold coupled with the high(er) flowing heads is in a way "the best of both worlds". We know the heads can support higher rpm power which can be seen by the stock HP numbers (HP=TQxRPM/5252). The stock engine makes peak TQ at 4000 rpm which is high for a truck engine so by using a lower LSA you can move/add more torque before that and the added duration over the stock cam can help carry it for longer which in the end will make more HP.