krexken

I'd like to put some Edelbrock Vortec (big port, small port?)heads on a friends truck. He also want's the biggest cam he can get away with without cutting or changing pistons. It's got 3.73s and 3000rpm stall converter. It already has a small cam and headers but the owner wants it be sound really nasty and, of course, make a lot more hp. He's not too concerned about giving up low end torque either. Any tips appreciated.

00ChevyScott

iTrader: (10)

Injectors are going to limit you unless you do a marine intake swap or another EFI system/intake

LowBlack99

iTrader: (3)

I see a LS swap in the future! Get a cheap 5.3 and start there, a 6.0 would be nicer but a 5.3 can be done for cheaper. Either are worlds above the current powerplant!!!

Fast355

Stick with the older engine. The 5.3 is not where its at, no matter how many people tell you that. My dad still wonders how my L31 Express can handle his LM7 Express with ease. Despite being heavier and only having 3.42 gears compared to his 3.73s, it will outrun his LM7. Stock for Stock it was close but the L31 would pull 3 lengths consistently by 80 mph. Now with Doug Thorley Tri-Y headers, S10 converter, and DIY PCM Tune, it will pull around 8 lengths on the 5.3 by 80 mph. The L31 is a great running engine and can EASILY be made to out-run the 5.3s. Nobody said you had to stay with the CSFI poppet setup but you can run the L31 electronics and make plenty of power. 0411 PCM swap with a 2002 Express van tune will work great too.

Craig Moates has a Tahoe with a NASTY little 383 (230/236@.050, .490/.500" cam, Ported Etec 200s,) in it running on the 2002 Express Van tune in Speed Density mode without a MAF.

00Silv4.8

iTrader: (10)

you really have a hopped up 350 in an express van?? haha, interesting setup

sonoma43

iTrader: (1)

seems like a waste to do that in a van.....But what do I know, to each their own

Fast355

Express van is as light as a 4x4 truck, so I guess to each his own.

Tig

iTrader: (2)

Fast,
Do you have a build thread on your van?
What kind of power can be made with a 99 Vortec?
How?
I was contemplating an LS swap in the future but, if I could work with what I have and make decent HP I would be a happy camper. I already have Thorley Tri Ys, not in yet. I also have a K&N FIPkit sittin with my headers. My other mods are listed below

Mark Johnson

iTrader: (1)

The heads are good on the L-31 but that's about it. Go the LSx route, you'll be waaaaaaay ahead............................

mds2004

If I had to do it again, I would have converted to a 5.3 or 6.0 instead up building my Vortec 383. Of course being in CA emissions has a big thing to do with out. But even with all of my mods listed I should only have ~320rwhp or so.

I think it would have been cheaper, have higher power potential, and better mpg.

With the L31, you need to change your intake manifold to make even somewhat decent power imo. Also without changing the ECU to the van ECU you cannot rev past 5800. BTW, my cam listed in my sig would definitely pull past that limit and still an untrained ear cannot tell I have a cam.