Building an engine on a budget.

[Chezoom]

So on Friday, I'm going to pick up another vortec 350 to rebuild for my 99. Im not going crazy with it, just a few things I'm going todo
Parts list:
Long tube headers- Size is unknown yet. One of my questions.
Full exhaust and high flow cats. size is unknown still.
K N intake with the heat shield done correctly.
PCM 0411 swap. Still researching but everyone says its better for tuning.
LT1 factory cam. Still researching but everyone seems pleased with this little mod.
Black bear custom tune.
E-Fan mod. Going this far, might as well squeeze an extra pony or two out of her.

Other notes. I want this truck to be legal.

Now for my questions.
With all my supporting mods, what size primary's should I run. This one has 1.625''
As for the rest of the exhaust. Size matters. 2.5" or 3" figuring out the right mixture of back pressure will be hard.
True duals or run a "Y" pipe? itll be dual tips with one on each side to exit.
Any other little small things I could do as supporting mods? Been thinking about MSD parts as well.
What do yall think?
Shooting for an increase of 50 hp an tq.
Factory ratings right now at 255PH and 330TQ

The Long tubes I'm looking at.
http://www.jegs.com/i/******/520/24...7&cadevice=c&gclid=CPGepbSSuMICFQmPaQodw5UAMw

 

[Gzes]

Back pressure is a myth. 3 in is fine. I'd do dual with x pipe. 50 he is gonna be more than exhaust. I'd do bolt ons then get a tune

 

[TigerEyz3]

Let's start with vehicle purpose... what are you looking to do with your vehicle? Tow? Offroad? Daily Driver?

Reason I ask is because you'll want your power/torque to come in differently. Not to mention, time in the seat will have an effect on what is deemed "acceptable" from a sound standpoint (exhaust related).

As far as your exhaust questions...

• For a mild 350 (up to ~400), I'd go with a dual 2.5" setup from the collectors to the muffler or mufflers (including the cats). That sizing helps to keep the velocity/scavenging where it needs to be while allowing plenty of exhaust volume to move.

• Legally, LTs are not considered 50-state legal (due to O2 sensor/cat relocations). Check your locality to be sure. Also, correctly adding a cross-over pipe puts you in the non-legal category as it moves the cats rearward (strictness of enforcement is subjective). If you look at the factory muffler (DI/SO), you'll notice it serves as a cross-over pipe (albeit behind the cats in the exhaust stream).

• Muffler selection is going to be a subjective decision based on tonal/volume preference. Bigger pipes will give a deeper tone. Larger tips amplify volume.

 

[livingez_123]

I'm not sure if building an engine and budget go together. You can plan for best case, but be ready for the worst. You never know what you are going to find until you open it up. At a min, bore, balance, line hone, surface the block, deburr everything. Then you can move on to the heads and keep adding the dollars. you have to remember your time is worth money too.

 

[Chezoom]

Let's start with vehicle purpose... what are you looking to do with your vehicle? Tow? Offroad? Daily Driver?

Reason I ask is because you'll want your power/torque to come in differently. Not to mention, time in the seat will have an effect on what is deemed "acceptable" from a sound standpoint (exhaust related).

As far as your exhaust questions...

• For a mild 350 (up to ~400), I'd go with a dual 2.5" setup from the collectors to the muffler or mufflers (including the cats). That sizing helps to keep the velocity/scavenging where it needs to be while allowing plenty of exhaust volume to move.

• Legally, LTs are not considered 50-state legal (due to O2 sensor/cat relocations). Check your locality to be sure. Also, correctly adding a cross-over pipe puts you in the non-legal category as it moves the cats rearward (strictness of enforcement is subjective). If you look at the factory muffler (DI/SO), you'll notice it serves as a cross-over pipe (albeit behind the cats in the exhaust stream).

• Muffler selection is going to be a subjective decision based on tonal/volume preference. Bigger pipes will give a deeper tone. Larger tips amplify volume.

I have another truck, I drive them about 50/50. my f150 does the towing. this isn't a mud truck but will go out an play every once in a while.
I live in dallas texas, I looked up the long tube rules here.
"On 1984 and later model light truck and passenger vehicles, the catalytic converter will be checked for presence and leakage.
1. Inspection Procedure. Examine visually.

2. Inspect for and reject if:

a. The exhaust emission system has been removed.

b. The exhaust emission system has been disconnected.

c. The plumbing or hoses are loose, broken, leaking, or improperly routed.

d. Air pump (air injection-type) belt is loose, removed, excessively cracked, frayed or has pieces missing.

e. The exhaust emission system has been altered in any manner to make it ineffective.

f. The catalytic converter has been removed, leaking, or disconnected on a 1984 or later model vehicle. "

2.5 is what I was thinking.

I was wanting to go with 3.5'' tips

muffler will be decided later.

---------- Post added at 04:16 PM ---------- Previous post was at 04:12 PM ----------

I'm not sure if building an engine and budget go together. You can plan for best case, but be ready for the worst. You never know what you are going to find until you open it up. At a min, bore, balance, line hone, surface the block, deburr everything. Then you can move on to the heads and keep adding the dollars. you have to remember your time is worth money too.

I realize this. time frames not an issue which is good. truck still runs okay but the spider is going out and she burns a bit of oil. Jst wanted to build something too. Im slowly going to collect the parts and build her up. I will address the transmission too at a later time.

 

[13JBecker]

For your exhaust, since you have to keep your cats to stay legal in Texas, I highly reccommend 2.5" straight piped from the cats back, to 4.5" tips. No crossover or x pipe whatsoever. I have this setup and love it. It's decently loud, but still sounds throaty. No excessive cackle either. My buddy has the same setup on a '97 pickup with the 350 but with 3" pipe instead and although it is deeper, it doesn't sound as powerful.

Don't believe people who say you need huge pipes. I have an 85 with a 400 horse 406 sbc in it running dual 2" straight pipes also with 4.5" tips and it breathes fine.

 

[Chezoom]

Yeah, I'm gonna stay 2.5. Got the motor yesterday. Gonna break it all down today and send it to the machine shop.

 

[TigerEyz3]

The headers you linked won't allow you to remain street legal (meaning all factory equipment and sensors are functional) as the EGR provision is not present.

You can block-off the EGR input on the intake manifold, but expect your fuel economy to drop (positive side, your intake will be a lot cleaner on the inside). On the other side of the options equation, you can add an EGR pipe to the driver side header to allow the EGR provision to remain.

As far as supporting mods, feel free to check out my mods list in the link from my signature for some suggestions. Don't know the condition of the rest of your drivetrain, but beefing up the transmission and rear-end are good places to consider when you're considering increasing your motor output. I've been pleased with the MSD components that I have.

Don't know what your budget is, but if you have room, I'd HIGHLY recommend getting ceramic coated headers. I know they're more expensive, but they'll keep your engine compartment much cooler and last a lot longer than non-ceramic coated headers.

 

[Chezoom]

So I add the EGR provision and then my truck will be street legal. What kind of power is your truck putting out?

 

[Goldhawg]

If you need parts for the fan swap, I have a volvo relay and JTR adapter that connects in the upper radiator hose, including the j/y BMW sensor. You wouldn't need the JTR once you go 0411 (which is what I ultimately did), but can help you get the efan in sooner. PM me if interested.