Bought a 94 GMC sierra 1500. Truck originally was a 305 auto(4L). Someone put a 350/th350 in it. Block code came up a 86 & up. Could be 2 or 4 bolt main? Haven’t pulled pan to check. Anyways, it’s a tbi set up. Stock headers. Stock intake. Just looking for the best bang for my buck performance wise. Looking to give the truck a little more of its true potential. Is it as simple as headers, cam, and maybe a better chip for the tbi?
CK5
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350 tbi options
- Thread starter Bdub76
- Start date
Start by looking up upgrades to the ignition system. A strong spark actually helps these a lot. Then an intake with a mild cam never hurts. Yes a chip/tune will be needed, but overall should make a solid runner.
You can still get custom tune chips made.
So you don’t think headers are important?
You got any recommendations for any of them?
I’ve read about a lot of problems. Or atleast alot of trial & error. Just looking to see if I should invest in the tbi set up or switch to carb or even something like the aces Efi stuff.
Aces efi is crap. If you want more power put a ls in it.
What an educated response. I’ve seen many people have success with just about every option out there. Aces efi included. Why would I take a perfectly good small block & spend thousands to switch it to a LS. A small block will do anything an LS will do.
I have this page saved; don't know how old it is
Yes, an LS swap will cost a couple of thousand dollars, but so will the aftermarket EFI system once you're done with a fuel system and all the odds and ends. The difference is you still have old iron SBC heads, iron intake, tiny cam, block exhaust manifolds, etc. In some cases, you still have a distributor, V-belts, and other old stuff. If it's built right, the SBC has a slight advantage in low-end torque, but the LS will destroy it from the mid-range on. A 6.0 with just a cam swap has been shown to make 2x the HP the TBI engine was rated for.
Ultimately, it's your truck and your decision to make. A TBI V8 is the period correct powerplant and people have been getting all the performance and reliability they need from them for decades. There are many headache stories with all of the aftermarket systems and also glowing reviews. You don't really need one or benefit much until you're doing more extensive mods. If your expectations are realistic that you will pick up just a little power and/or just a little MPG, there's no reason not to proceed.
Ultimately, it's your truck and your decision to make. A TBI V8 is the period correct powerplant and people have been getting all the performance and reliability they need from them for decades. There are many headache stories with all of the aftermarket systems and also glowing reviews. You don't really need one or benefit much until you're doing more extensive mods. If your expectations are realistic that you will pick up just a little power and/or just a little MPG, there's no reason not to proceed.
Just my opinion, headers won’t hurt anything, but the benefits vs costs may not be worth it. Headers performance is usually found in the higher RPM ranges where most trucks never run.
I started with a carbed 5.7, went to tbi just for off camber driving beyond the carb’s capacity.
The truck was a dog. I went to the Atomic EFI, heads, intake, camshaft, shorty headers (for fitment issues) and spent too much considering 2 years later the engine ate a lifter and cam lobe.
I had to pass emissions (inspection and on the rollers) and never had an issue with the tbi or Atomic EFI.
A went to the LS (2003 5.3), 4l60e and 205. I already had the d60/14bff axles. I’m running 5.13 gears on 37’s.
I’ve read posts where people get a good 5.3 where they drop it in and run it. Equally, people have tried it and it was a nightmare. They had to pull the engine and do a rebuild. Went to the bare block to refresh everything with a stage 2 cam. I was able to learn and flash the ECM myself.
It took me about 10 months of working almost every weekend from beginning to end. It was expensive when you add all the little things up.
I wish I saved my money on the tbi and Atomic and went straight to the 5.3, but I initially wanted to keep the truck a little more authentic and not “follow the trend”. I have no regrets doing the swap.
As someone else said, there’s not really a wrong engine. It comes down to cost, time, abilities and desire.
SClark08
Newbie
I have a Small Block 350 TBI in my '89 Blazer; here is what I have done to it:
1. Spark: new distributor, plug wires, plugs, & timing
2. Fuel: new fuel filter, cleaned & rebuilt throttle body
3. Air: replaced the aftermarket ram air intake with the factory air cleaner and AC Delco filter. No amount of ducting and shaving will improve your airflow with the swirl-port intake manifold. So save your engine and use the best filter you can.
4. Exhaust: mid-length headers, mandrel bent 2.25" intermediates, Y-pipe, 3" mandrel single side exit with a 20" Dynomax Super Turbo muffler
5. Coming soon: Harris Stage-1 Tune
6. Supporting Modifications: auxiliary engine oil cooler, auxiliary transmission cooler, transmission temperature gauge, tachometer.
Nice to have:
- 5.7L Vortec Heads and Intake manifold. I have not pulled the trigger on this as the price will land in the $1600-2000 range, based on parts and tuning. For the amount of annual miles I put on this rig, the fuel savings would take over 6 years to break even. I am happy with the power otherwise. I don't need to cruise at 70+ mph on the freeway; I am happy enjoying the analog ride at 65.
1. Spark: new distributor, plug wires, plugs, & timing
2. Fuel: new fuel filter, cleaned & rebuilt throttle body
3. Air: replaced the aftermarket ram air intake with the factory air cleaner and AC Delco filter. No amount of ducting and shaving will improve your airflow with the swirl-port intake manifold. So save your engine and use the best filter you can.
4. Exhaust: mid-length headers, mandrel bent 2.25" intermediates, Y-pipe, 3" mandrel single side exit with a 20" Dynomax Super Turbo muffler
5. Coming soon: Harris Stage-1 Tune
6. Supporting Modifications: auxiliary engine oil cooler, auxiliary transmission cooler, transmission temperature gauge, tachometer.
Nice to have:
- 5.7L Vortec Heads and Intake manifold. I have not pulled the trigger on this as the price will land in the $1600-2000 range, based on parts and tuning. For the amount of annual miles I put on this rig, the fuel savings would take over 6 years to break even. I am happy with the power otherwise. I don't need to cruise at 70+ mph on the freeway; I am happy enjoying the analog ride at 65.
