Hey guys. I've been on the performancetrucks.net website for some time now and have been reading and posting questions about various cam setups for my 02 Yukon. Here's the low down...

2002 Yukon Flex fuel 5.3
JBA catback (essentially a magnaflow muffler)

Wanting to get the Pacesetter longtube headers, offroad Y, Trailblazer stall (for milage purposes), and a cam...

And this is my next question: What do you guys think about a 208/214 .554/.559 110lsa in a 5.3 with the mods I've just listed?

There is a possibility I can get another 5.3 block for the low, and if that's the case, what do you guys think about boring it to the LS1 stock bore, forged mahle pistons and rods, and either the stock stroke or a 4.000 stroke, whichever would be best. If I do end up gettin that block for the low, the motor will be built for a weeee bit of boost , probably around 10lbs. Also, the cam would then be ditched because of the close LSA and get something with around a 115lsa.

Opinions?

 

first i dont think a 5.3 can be bored to a ls1 size because of water passages but i might be wrong. i do know that the cam is not what your looking for. that lsa is way to close for a cam that small. you are better off getting the truck cam from thunder racing because it makes torque and good power. the "old man truck cam" specs out 214/220 .600/.523 115 lsa +2 and does not need a tune, but obviously a tune makes more power. if you dont like this then go with a 224/228 .585/.590 114lsa. check also with patrick G, he's the man at cam choices.

 

A 5.3 block can be honed to a 3.9ish bore.

 

Yeah, the 5.3 can be bored to a 5.7.

Why exactly do you say the lsa is too short for a cam with a duration so low? I picked the low intake duration because I have a 5,000 lb suv, and I don't need my power to come on later in the rpm band. I rarely get it above 5k rpm's. I picked the 110lsa in order to bring the torque on sooner than with a wider lsa.

In an suv, unless you have some serious modifications, you won't be able to use anything much more than 220 intake without losing efficiency.

Anyone else have any other opinions?

 

morning bump

 

bump again

 

sorry been gone. i said to go with the cam so when you go FI you dont have to change the cam. a 110 lsa will bleed off to much boost while a 113 to 115 will hold the boost in the chamber longer.

 

crane 210/218 .551/.551 112+4 or 115+3 for FI.

 

Lots of good recommendations. If you're running stock exhaust manifolds, the trick is to open the exhaust valve earlier and close it later than you would if running headers. The challenge to moving over 5000 lbs of metal is overcome by building robust torque at lower rpm. Best way to do that is by chosing a fairly fast intake lobe, but keeping the duration short. If you stay with a 5.3L, I'd recommend something like an XFI 210 lobe on the intake and a 224 XE lobe on the exhaust. 210/224 .595/.568 114 +4. If you go to a 5.7, then run 4 degrees more on intake and exhaust.