Hot Rodding a 5.3L vortec

[00fxd]

Still ploting my conversion. If I were to aquire a late model low mile 5.3 ALUMINUM block engine, how much horse power could I get out of it say if I were to run an ls1-2 intake, headers and the hottest cam that would work with the stock ecm and sensors [and a tune]? Natually aspirated, no spray. Does this later engine have the 317 heads? Will that intake work on this engine?

[62LS1]

There's a guy selling some of these engines in the 'for sale' section and he talks about horsepower and changes via cam. Might look there.

[andrewb70]

A 5.3L is only about 20ci les than a 5.7L. So look at the power numbers of any LS1 buildup and subtract 20-30HP.

The 5.3L engine have 862 or 799 heads.

Andrew

[WS6]

they will make plenty of power. there are a number of magnacharged trucks making 500rwhp with a 5.3 and they are not spraying it either. Heads/cam can easily hit mid 300s at the wheels.

[Madspeed]

These days a head cam Intake long tubes and a good tune will yield at LEAST 400 RWHP
If your swapping it into a 1st gen then your replacing intake and putting headders on it anyways
Go get u some Paitriot perf heads that flow near 300 cfm

Or better yet wait till march and buy the GM perf LSX block capable of 500 inches for round 2k then get ya an eagle rotating assy.

Get the new L92 heads from a truk for under 1k complete that flow Over 300 Cfm, buy the holden intake injector combo for round 800 and youl have a SICK eng makin over 500 to rears

[00fxd]

Sounds like a cyl head swap would be nessesary. A hi reving small displace all aluminum engine sounds like fun tho.

[WS6]

or simply have a pocket port done to the 5.3 heads. The L92 heads are overkill on a 5.3.

[andrewb70]

or simply have a pocket port done to the 5.3 heads. The L92 heads are overkill on a 5.3.

Not to mention the fact that L92 heads will not work on a 5.3L

Andrew

[00fxd]

Thanks fella's, good input. The LS1 intake will fit no problem?

[andrewb70]

Thanks fella's, good input. The LS1 intake will fit no problem?

Correct.

Andrew

[BonzoHansen]

The guy in my local Camaro club works for HPTuners. He seems to think the way they program the truck motors, you can pull more HP out of them with just a new tune than you can out of an LS1.

[WS6]

You're right Andrew I forgot the L92 heads need a larger bore so the valves will fit.

There is always a lot that can be "cleaned" up to make the engine run better and simply respond differently and more to the individuals personal tastes. It's very subjective though. However, the biggest difference seems to be in the trans tables. My friend uses Flash scan for tuning and he has spent countless hours just playing with is 5.3 silverado. Sure he cleaned the engine table up and it ran better, but he messed with the trans tables significantly. He said throttle response is so much crisper because of the shift point changes he has made. This is up and down shifting. He has also been very pleased with how much power the little 5.3 has in such a big truck. His is extended cab. So yes even on a factory vehicle there are many changes that can be made that will make the vehicle much more enjoyable. that to me is more important than some number on a dyno graph.

[shanekennedy]

i believe the stock intake has the same hp as the 5.7 & more torque due to longer runners. so unless you need the hood clearance or hate the high rise look, save some cash & stay stock. fuel rail covers clean up the wiring mess above the intake.

[TA219]

I am in the process of installing a 5.3 in my 67 and so far i have run in to a couple of hurdles with running a LS1 intake... it will not work with the truck accessories. I did some searching and it looks like you can add a pully to the alt bracket and re-route the belt... or you can use a LS1 pully set up.. the only problem with that is the alternator bracket doesnt just bolt up. you have to drill and tap a 2nd hole in the block for it to work.

I dont know if the vette set up is better.



Also the stock coil set up is in the way of the fuel line on the smaller intake.

[WS6]

The truck intakes work very well copared to the LS1 intake. No contest compared to the LS6. The LS6 is a great intake.

[00fxd]

How much taller is the truck intake compared to the LS1 intake? I have to fit it all under the hood of a mid year Corvette.

[Madspeed]

or simply have a pocket port done to the 5.3 heads. The L92 heads are overkill on a 5.3.

You cant fit L92 heads on the 5.3 bore it has to be larger than 4.020"
or the valves will hit the cyl walls =)
I said to buy an LSx block and make a MONSTER for CHEAP

[Stoker420]

the truck manifolds by some accounts flow as good as the ls6 intakes. if you have one and can fit it under your hood use it if you like the looks.

[WS6]

LS1 nor truck intake out flows the LS6 intake in the upper RPMs. It simply doesn't happen. Midrange and low end sure they are close. The trucks have a low redline stock because of the intake and cam, not because the bottom end can't handle it. I personally will be spinning a stock bottom end 5.3 to 6k or 6200. The truck intake will not flow well enough to do this, so I have an LS6 ready to go on. The LS7 intake I have no idea about. The LS2 is a waste. People clammored for the LS2 when it came out and spent big bucks getting custom peices made to put it on their LS1/LS6 engines only to loose power and switch back to the LS6. The FAST intake is a waste as well unless you are big cubes or heavily pressurized.

00FXD. I can take some measurements tomorrow if I happen to remember. It's a few inches taller than the LS1/6 intakes though so it may be close. Of course switching to the stinger hood could solve that problem. But I think that would prove more expensive than swicthing to the car intake and car accessories.

[00fxd]

Thanks WS6, I have a stinger already . Those measurements would be very helpful . Any chance of a measurement from the centerline of the crank to clearance height of the intake ? Again , great info guys , thanks. .