How to upgrade a LO5 TBI engine?

[Chevelle_68]

I want to do some upgrades on the sbc350 LO5 210hp engine I have before I put it in my Monte.
I have found a guy selling an Edelbrock 3704 intake and a 3702 cam. Would any of this do me any good?
I have read that the Edelbrock 3702 cam is basically the same as the stock cam. So I guess it won`t do too much.
So what cam should I chose?
What other parts should I change?
I want to keep the heads I have, at least for this year.
I already have headers and a dual 2 ½” exhaust system. The car has a th700 transmission and 3.43 gears in the rear.

Thanks!!
HD

 

[RITTER]

The sky is the limit with a SBC

If the motor is setup with the TBI already, you will have to have a computer chip burned to get your maximum potential from a cam upgrade. Unless of course, you switch it to a carburetor. Keep in mind, if you go to a carburetor, you will have to change the distributor to an HEI setup and get a torque converter lock-up switch kit.

It all depends on your budget and your ultimate goal for the engine :wink:

 

[Chevelle_68]

The engine is a stock TBI and I want to stay with the TBI system. I want an engine that gives good gas mileage, and I guess I won’t get that with a carb. So I think I will just stay with the TBI setup on this engine, and play around with carbs on my bbc 498cid.
I was hoping to get around 270 to 290 hp out of this engine.
Will I be able to do that with the stock heads? I think I have the heads they call swirl port or something like that.

My plan so far is:
-Edelbrock 3704 intake
-do the recommended upgrades on the TBI unit
-change the pressure regulator
-TBI injector spacer
-custom air cleaner
-new spark plugs, wires, dist. cap and rotor, coil, fuel filter, oil filter, oil pump and water pump.
-under drive pulleys if I can find some for a decent price
-a custom chip

Would it help to put on a spacer between the intake and the TBI unit?

What cam should I go for with these upgrades?
I want to get a cam kit of some kind whit cam, lifter, timing chain, springs and retainers.

So what do you guys think so far?

HD

 

[RITTER]

The Edelbrock TBI intake with a 1" TBI velocity spacer and a good throttle body upgrade with a good cold air intake setup. You should see great fuel mileage numbers. TBI engines get surprisingly good fuel mileage. I would go with a good mild crate engine camshaft, like a ZZ4 or something. :idea:

 

[Chevelle_68]

Where can I find a cam like that?
Is it a straight swap?
What valve springs should I run whit a ZZ4 cam?

HD

 

[CHRIS.O]

Call one of the many cam companies and ask them, they are best suited to choose a cam for you. Be honest with yourself about what you want to do with the car, you will need to know things like compression, rear gear, stall speed etc to get a good recommendation from a cam company. Try comp cams cam quest program on their website. Find the downloadable version on their site though not the flash program, that one sucks. It will allow you to punch in engine specs and shows you a small dyno sheet of an estimated horsepower rating.

 

[othtim]

The stock heads suck. They run out of flow quickly. So I would focus on mods that improve your part throttle performance.
I did a bunch of mods to my dad's TBI truck. The throttle response improved miles

Performer TBI intake
"Ultimate TBI" mods
JET "stage 1" performance chip
Dual exhaust and hooker headers (wrapped with header wrap)
Open element air cleaner

The biggest problem I had with the 350 TBI was fuel pressure! I couldn't get enough fuel pressure with the stock system.
I recommend you get a TBI rebuild kit and re-seal the injector pod.

NEW FUEL PUMP AND aftermarket PRESSURE REGULATOR<--- this is extremely important if you do more mods. The old pumps will be weak and I found I was running extrmely lean on the top end...so lean the truck would even die if you went full throttle at over 4000 RPMs. So replace your fuel pump and get a regulator and fuel pressure gauge so you can know what its set at.

The best bang-for-buck mod you can do is to get a set of vortec heads, I think

Also dont forget, these trucks are impossible to hook up >_< traction mods are great. New tires are great too. I have 255/35/r17s all the way around on my dads truck. It handles extremely well!

 

[Chevelle_68]

I asked teck support at Summit, and he recommended this cam for my setup:
http://www.summitracing.com/parts/CCA-K12-234-2/

It seems like the guy selling the Edelbrock intake and cam wont split them up.

 

[RITTER]

That will be a good cam to go along with your stock heads. The heads on the LO5 are designed for low/mid range power for good lowend torque. They are definitely not designed for a big lift camshaft.

 

[Chevelle_68]

How will a carb intake whit TBI adapter work compared to a TBI intake?