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-   -   More power out of a 350? (https://67-72chevytrucks.com/vboard/showthread.php?t=728605)

klwebb 01-26-2017 02:36 PM

More power out of a 350?
 
I'm new to the whole adding horsepower thing. My 77 Silverado has a 350 in it. With the t350 tranny. It has true dual exhaust with I think flowmaster 40s. I want to put cherrybombs on though. Guys I bought it from (for $800) didn't know a whole lot about and it's past but they said it had been rebuilt a couple years ago. It runs really well, never let me down. But you can't have too much power, right? I've read about cams, intake, headers, etc. I'm on a super tight budget. What are some decent ways to get some more power out of these small blocks? What would you do first?

72bowtiestepper 01-26-2017 02:51 PM

Re: More power out of a 350?
 
Before throwing a lot of money into your 350, I would do a basic compresion check to see if the engine is in decent shape. Then a good tune up...new plugs & plug wires if needed. Also. cherry bomb glasspacks are not going to give you more power than the flowmasters you already have....just more noise. If you don't have headers....start there before going the big carb & cam route.

Dead Parrot 01-26-2017 03:48 PM

Re: More power out of a 350?
 
Search this forum for threads on timing and carb tuning. Those are the quickest and cheapest way to get a few extra horses and probably a bit better mileage as well. The stock timing and tuning was designed more to pass emissions standards then to maximize performance or economy.

If your compression check shows the basic block is good, might consider some vortec heads when your budget allows. If you go vortec heads, you will need a new intake as well but the exhaust stays the same.

Make sure you check your state's emission and inspection laws before you get too far along.

akart 01-26-2017 05:08 PM

Re: More power out of a 350?
 
Quote:

Originally Posted by Dead Parrot (Post 7838934)
Search this forum for threads on timing and carb tuning. Those are the quickest and cheapest way to get a few extra horses and probably a bit better mileage as well. The stock timing and tuning was designed more to pass emissions standards then to maximize performance or economy.

If your compression check shows the basic block is good, might consider some vortec heads when your budget allows. If you go vortec heads, you will need a new intake as well but the exhaust stays the same.

Make sure you check your state's emission and inspection laws before you get too far along.

Summit catalog: Vortec short block 220 hp, basic short block 260 hp, and the vortec heads are not a cheap add on.
Tune the engine then maybe some headers. I put on an Edelbrock 600 cfm bought the tuning kit too. You can only adjust the idle mix without it and get there fuel pump for correct pressure to carb. I have an '82 K20 an it has plenty of snort. Jumps right op to 85mph and there is a lot left. Think about your mods, more HP means more fuel. Good luck!!

bbbc10 01-26-2017 05:26 PM

Re: More power out of a 350?
 
I wouldn't even waste the money on the 350

franken 01-26-2017 11:32 PM

Re: More power out of a 350?
 
Some good suggestions above, but a basic tuneup is pretty much where to start, possibly after the compression check to verify engine health.

Stock plug wires are prone to failure, and not firing a cylinder is a big power robber. Correct spark advance. and ignition are also important.

77 would have a cat OEM and a dual exhaust probably eliminated that. Chances are a change to different mufflers won't make much performance difference.

Go fast parts are in reality secondary to glaring needs bits below...

Unfortunately, old cars are a bit expensive as far as needing initial work goes. They typically need a complete fluid change (engine, trans, diffs, brake, coolant), which costs more than people think. Brakes, front end wear parts are normally worn as well. Wiring is typically trashed, and I normally on a new old vehicle have to put in a new battery box, PS pump, box and hoses.

That's a few thousand to pay someone for the work and maybe half for parts.

Ziegelsteinfaust 01-26-2017 11:40 PM

Re: More power out of a 350?
 
Myself i would just cruise what you have, and slowly build a Vortec 350 or LT1.

In my area LT1 350's are fairly common in the junkyard, and with basic bolt ons are good for nearly 350 hp 400tq. Plus you can swap this cam into a Vortec 350 for comperable results.

I grew up on flat tappet cams, but i would not use one again in a sbc.

MikeB 01-27-2017 11:43 AM

Re: More power out of a 350?
 
Quote:

Originally Posted by bbbc10 (Post 7839026)
I wouldn't even waste the money on the 350

Not very helpful.

Quote:

Originally Posted by Dead Parrot (Post 7838934)
Search this forum for threads on timing and carb tuning. Those are the quickest and cheapest way to get a few extra horses and probably a bit better mileage as well. The stock timing and tuning was designed more to pass emissions standards then to maximize performance or economy.

Yep, gotta start with the simple stuff.

Tom 01-27-2017 01:08 PM

Re: More power out of a 350?
 
Your all assuming she needs a tune up. She said it runs great no issues, so lets skip telling her to buy spark plugs. Although for only $800 I get where you guys are coming from.

Long tube headers are a good upgrade for low bucks.
Aftermarket carb won't get you any more power.
Camshaft would be my next step, if you can handle that kind of work. Otherwise, its alot of money to pay someone to install.
Intake manifolds are cheap

In the end, more power cost a lot of money. Being on a budget, you don't have a ton of options. Most upgrades will cost as much as you paid for the truck or more if someone is installing for you.

daddyjeep 01-27-2017 01:30 PM

Re: More power out of a 350?
 
There are a lot of used 350 parts out there since that engine has been around forever.You might be able to find at least a decent used intake and possibly headers. Headers might be a little riskier to buy used though as they could be rusted or cracked. It is worth at least looking around since budget is an issue.

Nick_R_23 01-27-2017 01:41 PM

Re: More power out of a 350?
 
I agree with Tom here. But what is a super tight budget to you, OP? Give us a number to work with.

Heads, cam, intake, and compression are going to be the best ways to get more out of an SBC, but they tend to cost quite a bit. Vortec heads flow well and can be had for cheap, but are limiting on cam sizes in stock form, requiring expensive machine work.

Honestly, if I had a bone stock 350 and wanted more out of it on the cheap, I would tune the distributor for a more aggressive curve and get quality aftermarket module and coil, I would get an aftermarket intake (typically found on CL for <$100), find a decent set of headers (usually $100-$350 depending on new or used), and then set the truck up with an R/V cam and new lifters (about $300). I would leave the stock Quadrajet on there if it is still there, as it will provide good economy driving around, but come to life easily if you get on it.

You'll find it hard to beat that setup for the bang for your buck.

klwebb 01-27-2017 01:57 PM

Re: More power out of a 350?
 
Quote:

Originally Posted by Nick_R_23 (Post 7839873)
I agree with Tom here. But what is a super tight budget to you, OP? Give us a number to work with.

Heads, cam, intake, and compression are going to be the best ways to get more out of an SBC, but they tend to cost quite a bit. Vortec heads flow well and can be had for cheap, but are limiting on cam sizes in stock form, requiring expensive machine work.

Honestly, if I had a bone stock 350 and wanted more out of it on the cheap, I would tune the distributor for a more aggressive curve and get quality aftermarket module and coil, I would get an aftermarket intake (typically found on CL for <$100), find a decent set of headers (usually $100-$350 depending on new or used), and then set the truck up with an R/V cam and new lifters (about $300). I would leave the stock Quadrajet on there if it is still there, as it will provide good economy driving around, but come to life easily if you get on it.

You'll find it hard to beat that setup for the bang for your buck.

Your plan seems to be a good idea that I can work on over time. I will probably start with an intake and headers. And look into tuning the distributor and the module and coil.

klwebb 01-27-2017 02:01 PM

Re: More power out of a 350?
 
Quote:

Originally Posted by bbbc10 (Post 7839026)
I wouldn't even waste the money on the 350

Well if I had the funds, tools, and experience to swap it out for something worth wasting money on, I definitely would. I'm a senior in high school working part time at an autobody shop, and also paying $30 a week in gas just to get to work lol.

northern 85 05-05-2018 06:35 AM

Re: More power out of a 350?
 
The 350 is a great engine,it can run great, but still not be tuned for peak performance. Like others have said check comp first,then total timing and carb jetting. You might have some hp just waiting to be unleashed! Then give us your info of intake, carb, dist and exhaust set up.


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