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vtwinsport 02-13-2009 10:51 PM

Small block horsepower addition
 
Hey all,
I have a stock small block 350 in a 76 c10 with edelbrock carb,performer intake and Hedman headers. Stock HP is about 165. Maybe I gained 10 HP with the above mods?
What kind of horsepower can I expect with a cam, new free flow exhaust? What else can I do other than cranks or pistons? What does it take to get 250-300 HP out of a small block?
Thanks in advance.

cochino12 02-13-2009 11:08 PM

Re: Small block horsepower addition
 
Quote:

Originally Posted by vtwinsport (Post 3143045)
Hey all,
I have a stock small block 350 in a 76 c10 with edelbrock carb,performer intake and Hedman headers. Stock HP is about 165. Maybe I gained 10 HP with the above mods?
What kind of horsepower can I expect with a cam, new free flow exhaust? What else can I do other than cranks or pistons? What does it take to get 250-300 HP out of a small block?
Thanks in advance.

slap a set of vortec heads and a cam on it, should wake it up really well.

http://www.chevyhiperformance.com/te...ild/index.html

silvereagle07 02-13-2009 11:10 PM

Re: Small block horsepower addition
 
You could always upgrade the top end of the engine. Heads , cam , roller valvetrain with a carb to match.

I followed this article when I built my engine. http://http://www.chevyhiperformance...ams/index.html

Vixvega 02-13-2009 11:11 PM

Re: Small block horsepower addition
 
Original everything in the engine still? Or has it been rebuilt with new bearings etc? A good high powered ignition starting with distributor, coil and box, low interference wires etc. choose parts that work together, Flowmasters with x pipe. Make SURE the cam/springs and everything else in the valvetrain is 100% compatible. Pull the heads, have a reputable shop do as good a quality 3 angle valve job as you can afford, upgrade the valves to 2.02x1.94s and polish the ports taking as much roughage/casting flash off them as you can to improve flow without removing material. Consider having your shop take a pass with the mill on the heads for a little more compression but don't go crazy. Your engine is nothing more than an air pump, the more you pass through it the better it will run.

Trick76 02-13-2009 11:12 PM

Re: Small block horsepower addition
 
I would look into some vortec heads, or good aftermarket castings if you are shooting for 300 hp

Oilbrnr 02-14-2009 12:44 AM

Re: Small block horsepower addition
 
Subscribed.

I think I'm in a similar situation. I have a ten year old crate GoodWrench 350 that was put in by the original owner here in Phoenix by Courtesy Chevrolet. He was in his seventies at the time and only put 25k on it (with records/receipts) when I bought it from him last year. I was/will be using it as a DD to give my Dmax a break. I have freshened up the interior a bit and am in the process of putting in a 4" lift, but the next step is to see what I can do under the hood.

My 1977 K5 is in the 49 state Federal HD emission status which means that I'm pretty much wide open to mods as long as it passes CO and HC here in Maricopa county.

I'd like to stay with a Q-Jet and run Hedman Elites (IIRC 68030) which WILL clear the manual clutch linkage on a 465. BUT I don't know if they will work with Vortech heads.

Not to Hijack, but any thoughts appreciated!

Albatrossian 02-14-2009 01:49 AM

Re: Small block horsepower addition
 
The key to making power is heads. A good set of free-flowing heads will net you the most power. If you're willing to pony up the cash, get them ported and polished with a good 3 angle(or better) valve job. Next is exhaust. A good set of headers, an x-pipe, free flowing mufflers and pipes are the way to go. An HEI ignition with a good set of wires and MSD if you can afford it. A good cam in the .460-.480" lift with about 270 duration.Go with a dual plane intake.. there's alot of good ones out there, so it's mostly brand choice these days. All of these will make you 300 hp.
Now all you gotta do is get it to the ground...
:metal:

Trick76 02-14-2009 01:57 AM

Re: Small block horsepower addition
 
Small block headers bolt right up to Vortec heads

Quote:

Originally Posted by Oilbrnr (Post 3143400)

I'd like to stay with a Q-Jet and run Hedman Elites (IIRC 68030) which WILL clear the manual clutch linkage on a 465. BUT I don't know if they will work with Vortech heads.

Not to Hijack, but any thoughts appreciated!


vtwinsport 02-14-2009 10:33 AM

Re: Small block horsepower addition
 
Thanks for all the input. I wasn't sure where to start but that helps.
How much does a valve grind, bigger valves and porting cost relative to buying vortecs? I like the idea of using the heads I have as I know everything bolts up right now. I read that changing to vortecs can mean other part changes like valve gear, covers, intake etc.

cochino12 02-14-2009 11:32 AM

Re: Small block horsepower addition
 
Quote:

Originally Posted by vtwinsport (Post 3144170)
Thanks for all the input. I wasn't sure where to start but that helps.
How much does a valve grind, bigger valves and porting cost relative to buying vortecs? I like the idea of using the heads I have as I know everything bolts up right now. I read that changing to vortecs can mean other part changes like valve gear, covers, intake etc.

I see new sets of vortec come up on cragislist from time to time around $400. You will also need a set of self alligning rockers, valve covers, and an intake, I think thats it.

78 Chevyrado 02-14-2009 11:39 AM

Re: Small block horsepower addition
 
be sure to buy an aftermarket timing set. if you buy a stock replacement, it will retard the cam. they built the retard into the cam sprocket.

cochino12 02-14-2009 11:58 AM

Re: Small block horsepower addition
 
Quote:

Originally Posted by 78 Chevyrado (Post 3144261)
be sure to buy an aftermarket timing set. if you buy a stock replacement, it will retard the cam. they built the retard into the cam sprocket.


I knew I forgot something :lol:

asphaltburner 02-14-2009 01:55 PM

Re: Small block horsepower addition
 
Yo! Check into a roller chain and sprockets to replace the timing set,...I run Summit's on my Crane cam. Roller, to reduce friction, wear, and remain more accurate, and allows cam advance of up to four degrees.
Make any engine breathe better, intake and exhaust (and through the head), and reduce engine effort, and you'll build HP.
Both of my shortblock 350s sport big-valve World heads with roller rockers and 67cc chambers (to increase compression), Weiand manifold, Crane towing cam advanced 4 degrees (via roller chain and sprockets), Shorty headers (to 2.5" exhaust, "H" pipe, and turbos), 600 Holley on a 2.5" spacer, HEI with MSD, and a flex fan and electric fuel pump to further reduce engine effort.
Todd.

vtwinsport 02-14-2009 02:19 PM

Re: Small block horsepower addition
 
Thanks again.
I see allot of reference to roller cams, chains and rocker arms. I'm assuming they're worth it then?

asphaltburner 02-14-2009 02:40 PM

Re: Small block horsepower addition
 
Yo! Roller chain and sprocket are CHEAP and fit without mods. Roller tipped rockers are also CHEAP and require only tall valve covers, but a roller cam is a bit more expensive and requires matching valve train parts. Tremendous friction reducers, as you can well imagine, replacing a sliding metal on metal interface with a rolling/rocking one.
Keep your lift under 0.500 and you'll be fine. My Crane cam is spec'ed at 0.420/0.442 with a duration of 262/272. I have no noticable "lope" and I like it so much in my Camaro that I didn't go with a bigger cam to build the second 350 V8 for FRANKENTRUCK.
Todd.

charlie diaz 02-14-2009 02:51 PM

Re: Small block horsepower addition
 
yeah, they're worth it. There's a reason chevy went to a roller set up in the 5.7's. It is less friction causing it to be more efficient, making it easier for the engine to work. A new set of Vortec heads from Scoggin Dickey will run you around $600. To each his own, but I wouldn't spend the money reworking old heads, not with the way the aftermarket is now. You'll end up spending a lot of money at the machine shop reworking the stock heads and still not get the same flow numbers that you would on an aftermarket set. World products makes a great flowing set of heads for a really great price. But if you're going for numbers matching on your block, do like the other guys said and get bigger valves on your stock heads. Also make sure to get them decked. This will bump up your compression a bit and give the block more grunt.

vtwinsport 02-14-2009 02:59 PM

Re: Small block horsepower addition
 
that's great guys. I'll probably look for aftermarket or vortec heads then and cam up to 460 lift, 260 area duration. Looks like it will cost about 1500 when all is done.

staggerd86c-10 02-24-2009 02:39 PM

Re: Small block horsepower addition
 
take a look at a set of the iron vortec heads that patriot performance puts out, i just finished putting a set on my truck with some 1.6 roller rockers and an airgap intake night and day differnce i may be at the 300hp mark. i do have a cam and full exhaust and things like that but the heads made a big difference.

keithaz24 02-25-2009 03:01 AM

Re: Small block horsepower addition
 
I heard just replacing fan setup with electric fan should give you small boost. every thing that is driven eats hp... Fuel pump, waterpump, fan, + throw in some roller lifters and roller rockerarms.


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