sschevellefan

alright guys, been looking at stuff all day trying to learn more about these LS engines. I`m going to be picking up a 2001 5.3 with 200k miles tonight so it`s going to need a rebuild but I want to add some performance for sure. So far I think I have the am narrowed down to either the GMPP hot cam or this one from Lunati,

http://cgi.ebay.com/ebaymotors/LUNAT...Q5fAccessories

I`m pretty sure I want to use the performer RPM since I don`t think the Vic JR will clear my stock hood. Will probably use the MSD ignition too.

Possibly thinking of heaving the heads ported as well since they will need a rebuild anyway. I don`t know if I`ll install bigger valves or if I even need to, still learning about these engines.

This is going to go in my 65 el camino with a th350 with a 3000-3500 stall and whatever gears are needed to work with the set up. looking to make a nice street car but still want to race it a bit. Would like to hit mid-low 12`s or maybe high 11`s. I`ve seen trucks running low 13`s with a cam and bolt ons and a good tune so I figured a little lighter car, a little port work on the heads and I should be able to get to my goal. I don`t care what the HP numbers are, don`t mean anything to me. Just want to run the ET`s that I want. Also, this isnt my daily driver so the combo can get a little wild but I`m trying to keep things simple. What do you guys think? Am I on track?

speedtigger

iTrader: (16)

The little 5.3s don't have a ton of torque compared the the 6.0s.. 5.3 are also know to like converters in the 3500 to 4000 range for good track performance.

Either of those cams should work, but you might consider a closer lobe separation angle like 110 degrees. This will help bring the torque in a little sooner although it will produce a rougher idle.

I can see mid to low 12s with the 5.3 in your Elco with a cam like you have listed. If you want 11s, my formula would be: ported heads, 4,000 converter, 4.11 gears, 750 DP Holley and a cam in the 230/235 range on 110 LSA.

sschevellefan

yeah I know most of the LS1 cams are usually 112-114LSA so going to a 110LSA would help for sure. Most of my builds have been 327`s and most of those were on a 108LSA so a 110LSA would be fine. Ill have to look into it. I just got back from picking it up. the heads have a 862 cast into them. Are they any good? It`s from a 2001 Tahoe if that helps. What is the stock compression on these things? My plan is a pretty much stock rebuild on the shortblock with new stock type pistons and better rod bolts, a perfomance cam and redo the heads and maybe do some porting on them. Is there anything wrong with the performer RPM intake? Seems most guys use the Vic JR.

bigmandengo

iTrader: (21)

The victor jr and performer are basically the same height. The compression ratio is 9.5:1 on a stock 5.3

Paul57

I will be running the RPM but had my custom cam spec'd so my shift points are at 6000 and not out of the optimum range of the intake.

speedtigger

iTrader: (16)

They have different strengths. In general the Performer RPM has more power below 5000 RPM on a 6 liter and the Victor Jr. will have more power over 5000 RPM on a 6 liter. On your 5.3 it will be a slightly higher RPM. It just depends on what you are building as to which is better for you. It is discussed at length in some other threads in the carb forum. You can find it with a search.

Paul57

Most guys seem to like to wind (rpm) these things up so that may be one reason the Vic is more popular. The off-the-shelf cams seem to be more on the high RPM side from the little bit I have seen/read. For a "mostly" street car, I think the RPM is the wiser choice. Torque and traction win on the street.

sschevellefan

Yeah I`ve been reading a bunc of threads and I think the vic JR will actually work out for me. I`m even thinking of going a bit bigger on the cam than I originally planned. Its going to depend on what I do with the heads. Not sure if I should have mine done or go with aftermarket heads or find a set of OEM`s that are already done the way I want them. Its a tough call.

Paul57

Yeah, there are a ton of options with these things. This is my first LSx build and it is quite the learning experience. One thing is for sure...they make a lot more HP and Torque than a traditional SBC. It is tough to go wrong no matter what you choose as long as the rest of your build is set up for the same range (rpm). Although, I am probably not sharing anything new to you with that info. The 243 and 317 heads are great for stock castings and flow very similar numbers. That is a good place to start if you don't want to go with the big $$ stuff.

Paul57

I'll give you another tip that I found...and I think it is because these things build so much more torque in the lower end of the power band. I read a post where a guy has done an extensive amount of research on here with guys that changed gears from highway (3.23-ish) to performance (4.10-ish) gears and they are only gaining like .1 in the 1/4 if they already have a significant converter (3000+). That is why I went with the 3.42...give up very little in the 1/4 with nice MPG benefits for a regular driver. Just thought I would share.