99-7.4 suburban 2500 engine upgrades

[Dogman]

I have two 1999 suburban 2500's both with the 7.4 vortec, both 4:10 gears , one 4x2, the other 4x4.

I'd like to give the 4x2 just a little more power. I don't want to go crazy. Will a cam upgrade help? And exhaust?

 

[Chewy1576]

A tune would probably wake them both up a bit. Cam and exhaust would help too. You would want to do a tune if you upgraded the cam anyway.

 

[BowtieBrody]

Exhaust definitely; even something as simple as a cat-back kit wakes up a bone stock truck.

And close to every 454 guy on here will tell you tuning, the stock tune on these trucks is super disappointing, even if you just stuck to tune/exhaust it would be a night and day difference.
Cam swaps are a little more invasive than one would think, so it'd be best to just stick with external upgrades unless you're dead set on a cam swap.

 

[Dogman]

Can these vortec 7.4's be made to run good power numbers?

 

[Christian Steffen]

Depends on what you consider to be good power numbers, and how much money you want to spend. Has anyone seen dyno results for exhaust and a tune? I can't say that I have.

 

[Tom P]

Tune and Exhaust are the easiest bolt-ons to do, and even with the mild tune I got, it did amazing things for my truck. Doing a cam will require more than just a cam and lifters. You will have to buy new adjustable rocker arms. The amount of lift you can run is limited as well. Comp Cams has a few really good options depending on what results you're looking for. You could try just replacing the timing set, as Christian has discovered, the cam timing is retarded by a few degrees from the factory. A new timing set will advance the cam to a more normal timing and can really boost low end power. A full tuneup, New Bosch injectors, and a new Fuel Pressure regulator are good preventative maintenance that can also revive an engine that hasnt been touched in a while. Also, before you get too far into adding upgrades, it would be a good time to do a compression test, and fuel pressure test, just to make sure you're batting with a full lineup there.

 

[Dogman]

Anyone know of a tuner in the Chicago area that could work on my 7.4?

 

[my name is alex]

Anyone know of a tuner in the Chicago area that could work on my 7.4?

I'm pretty sure I've heard Blackbear mentioned a lot on the forums http://www.blackbearperformance.com/

I don't know if they're local to you, but they can tune via mail in.

As far as 'upgrades' I just ordered some new bosch fuel injectors for my 7.4. I'm hoping to have them installed this week and see if the truck feels any different - it'll hopefully start better when warm at least!

 

[Tom P]

I'm pretty sure I've heard Blackbear mentioned a lot on the forums http://www.blackbearperformance.com/

I don't know if they're local to you, but they can tune via mail in.

As far as 'upgrades' I just ordered some new bosch fuel injectors for my 7.4. I'm hoping to have them installed this week and see if the truck feels any different - it'll hopefully start better when warm at least!

Make sure you replace the Fuel Pressure Regulator and the vacuum hose while you're in there. That is usually one of the main culprits in the Hot Start problem.

 

[my name is alex]

Make sure you replace the Fuel Pressure Regulator and the vacuum hose while you're in there. That is usually one of the main culprits in the Hot Start problem.

Thanks for the tip Tom. I dropped the Burb at the mechanic today, and I did bring him a new FPR as well. You think I should specifically mention the vacuum hoses to him, or is this something he'd notice while workin' on it?

[my apologies for the thread jack!]