Put a 383 stroker in 97 Ext cab. Put down 330 H.P. and 380 T.Q. to the wheels with the stock intake manifold and fuel injectors (rated at 19lbs) Obviously the LS1 based engines are superior to the poor design of the 96-99 Vortec trucks, but thought I'd share my results with you guys anyways. Engine is a basic build up that I drive every day. I have not seen anybody else do this kind of setup with an L31 without going to an aftermarket EFI or carb. Even though the numbers arent crazy I'm happy with the buildup. What do you guys think? Next engine will be an LS1 with similar of more cubes. Love the site and appreciate the OBDII info. It has helped me alot with tuning and using auto-tap! Thanks!



.....any suggestions on more power? How much are electric fans worth?

 

Sounds pretty sweet. What did it dyno stock?

 

They dyno about 200 RWHP stock. They're rated at 255 hp stock.

 

Nice, a big torque curve is cool. I dunno if you go to fsc.com but a cat by James B there is trying to adapt the Mercuriser or Marine Vortec 350 intake manifold to his motor...may be something to look forward to. You guys could try contacting FAST. They are making a manifold for the LS1 currently.

Electric fans, roller rockers, BBK TB maybe, GMS MAF. <---- More mods if you don't already have them perhaps.

Is it possible to adapt an LT1 intake to the Vortec heads?

 

Sweet numbers.

I thought they were rated at 280hp/330tq from the factory.

What crank did you use, is it cast?

Ported heads?

I have a L31 1999 Tahoe 2WD. If the motor were to go in the next 6 months I would build something.

 

Anyone heard of someone putting down numbers similar to mine N/A with L31 injection??????

Using forged 4340 Eagle crank

Ported the heads myself

 

Hotrod had an artical and they did about the same thing and came up with 250HP at the rear

 

I was wrong,They layed down 302HP
http://www.online-racer.com/Suburban...troker_in_.htm

 

That power is not at the wheels, its SEA corrected flywheel horsepower. It means they probably put down about 250 to the wheels. In my opinion a weak build up.....but they were going for an emisions legal setup.

 

Hey if you putting down 330HP to the rear wheels by stroking it mild cam bolt-ons porting and tuning then my hats off to you, if it has perfect drivebility and the fuel milage hasnt changed much,then congradulations. I was beinging to belive that much HP could not be made with the stock injection.Have you ran it through the 1/4? have you ran it againts a strong running stock vortec for comparisson?Im courious.