This a good cam?

[CAMPYROCKS]

I have a 99 sierra 1500 reg cab short box 4.8L with 4 10 rearend, cat back exaust, short headers, knn intake, hypertech (soon to be westers),with 20" wheels. I am looking to do a cam upgrade anyone have thoughts on this one its a comp cam XR265hr-14 Part # 54 412 11 its from 12-6000 rpm I want to build a 1/4 mile truck.

[MrPbody]

Okay, a "level set" is in order. You have the small LSx engine, right? You also have an upgraded air inlet? K&N makes air pipes and filter systems. You still have the GM intake manifold.

For drag racing, many changes are called for. For street/strip, it isn't as complex. The cam you listed would be a reasonable cam for a street car/truck. It's a bit on the small side for racing.

FWIW, when you use the term "1/4 mile truck", one would assume a trailer queen, for racing only. Is that your true intent? Please give more detail. I can make a specific recommendation based on that.

Jim

[SilentNIght1647]

I thought I was going crazy I had the Comp master catalog on my lap for at least 20min before I found the cam you listed. I agree with the above poster but would like to add a side note, that cam is going to be plenty for an initial swap until you want something with a little more rump and alot more thump.

[zx2guy]

does anyone know a good cam for a 2v 351 cleveland? (motors out of a 73 mercury xr 7) im debating if i should convert it though to a 4v.

[MrPbody]

Leaving the 2-bbl. carb on the Cleveland would make it an exercise in futility, to put a performance cam in there. I would certainly change to a 4-bbl. Edelbrock makes a Performer intake for 2-bbl. heads, to use a Holley or Motorcraft carb.

For a street performance engine, I would avoid 4-bbl. heads. They have such a large intake runner, they don't make any power until RPM level is over 3,000 (or more...). The 2-bbl. heads can make plenty of power at street speeds. We usually install 2.190 intake valves and 1.750 exhausts (4-bbl. size). Screw-in studs and guideplates aren't a bad investment either.

For the cam? If you want a mellow idle and good torque, Comp XE262H. If you want more high-end and a "lope", XE274H is the ticket. Both are excellent street grinds.

Jim

[zx2guy]

so why would you change it to a 4 bbl? you got a good layout here for the 2 but ild also like to hear about the 4bbl. and also what bout the carb what would you suggest? and what about the jetting? and is there anything that you would do to the head (ie port polish) < or leave that alone since replacing will be hard since there are only so many out there now? and what about pistons and crank and rods... any suggestions? maybe forged pistons so if i want to add more power of somekind it can take the added compression?

[MrPbody]

The 2-bbl. carb is the restriction. The 2-bbl. heads are quite good when upgraded for street performance. As stated in the previous post, install larger valves and good valve train pieces, and the little puppy will make GREAT power.

The 4-bbl. heads really are quite useless for street driving. Many a 2-bbl. headed engine has been in the 11s. 6,500 RPM is no problem.
You NEED a 4-bbl. carb to provide the additional volume the engine needs to rev to a higher point. For an engine in the 350 CID range, a 650 is an excellent choice. I would go with an AED Holley 650HO.

There's very nearly no limit what you can do to warm up the Cleveland. Lay out your specific performance goals, and I can outline a build for you.

Jim