Where's the horsepower???
August 1st, 2016, 07:53 AM
#1
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Join Date: May 2016
Location: Walterboro, South Carolina
Posts: 197
Where's the horsepower???
I've made the decision to pull my motor out here soon to do some work. Right now it's a few months old, bought it as a remanufactered engine to stock specs of a 69' 350 rocket. The only thing that's not stock as we speak is the cam in it, it's a mild comp cam, Edelbrock performer intake, and flowtech headers...my question is, does anyone have blueprints on getting more horsepower out of a 350? I want more power but want to be able to drive an hour or so out of town on the weekends with no issues. I know the heads are something I am definitely replacing but not sure who to go with, Modello, Edelbrock, etc etc. Any suggestions are greatly appreciated!
Last edited by Cpriester123; August 1st, 2016 at 07:59 AM.
August 1st, 2016, 10:16 AM
#3
4 Barrels of Laughs
Join Date: Jun 2016
Location: I moved to pittsburgh so I can be near Primantis
Posts: 405
I can give you GM part numbers to get HP out of a 350, a chevy 350....but you want an olds 350 and its a bit harder given 40+ years of no factory support.
The problem in a nutshell is, it cannot breathe. The stock heads are lousy and essentially unfixable and the performance W-car heads are marginally better but still lousy by todays standards. The aftermarket is pricey and getting hard to find. Im pretty sure the edelbrock stuff is no longer produced - just NOS only and I have heard that mondello is a company in name only and does not produce the same stuff they did in the 80's.
at any rate go with what we know after 40 years of building and dyno work - the cylinder itself is going to behave like a chevy with an overbore and slightly lessened stroke. So there will be no reason why IT is the impediment if you form the OTHER half of the combustion chamber - the piston top. get a replacement that is similar to a chevy G block or a vortec head machine, then worry about the heads.
no cam will do any good if the ports, turns, valves and bowls cannot accept the airflow. since there are no 'known good' modern castings or moldings of a small block head to do a CNC copy of, you gotta start from scratch and use a flow bench. a die grinder and dremel to not a good flow make, you have to make a port that flows well from .100 to .500 lift at a decent vacuum signal - its a bit of work to set up the jig, generally hold a valve open by hand, use a piece of aluminum or thick lucite with a super strong vac on it, measure vacuum and flow and grind away...but dont listen to me, there are hundred of books and you tube videos showing the process.
then once you get one intake and exhaust port done, take the heads to a shop with a CNC copying tool (haas, centroid etc) and mastercam 10 or better (for symmetry issues) and let them scan the one and cut back the rest. cost you a couple hundred dollars in most cases - or more if the shop has to cut a jig for an olds head which is most likely - almost no race teams run rockets.
once you get this done if the edelbrock intake is still around all you need is the performer series - no small block is going to spin fast enough to exceed that capability and still be streetable.
I think if you use BBO heads on the 350 the only edelbrock intake that fits is the performer rpm but I could be wrong.
The problem in a nutshell is, it cannot breathe. The stock heads are lousy and essentially unfixable and the performance W-car heads are marginally better but still lousy by todays standards. The aftermarket is pricey and getting hard to find. Im pretty sure the edelbrock stuff is no longer produced - just NOS only and I have heard that mondello is a company in name only and does not produce the same stuff they did in the 80's.
at any rate go with what we know after 40 years of building and dyno work - the cylinder itself is going to behave like a chevy with an overbore and slightly lessened stroke. So there will be no reason why IT is the impediment if you form the OTHER half of the combustion chamber - the piston top. get a replacement that is similar to a chevy G block or a vortec head machine, then worry about the heads.
no cam will do any good if the ports, turns, valves and bowls cannot accept the airflow. since there are no 'known good' modern castings or moldings of a small block head to do a CNC copy of, you gotta start from scratch and use a flow bench. a die grinder and dremel to not a good flow make, you have to make a port that flows well from .100 to .500 lift at a decent vacuum signal - its a bit of work to set up the jig, generally hold a valve open by hand, use a piece of aluminum or thick lucite with a super strong vac on it, measure vacuum and flow and grind away...but dont listen to me, there are hundred of books and you tube videos showing the process.
then once you get one intake and exhaust port done, take the heads to a shop with a CNC copying tool (haas, centroid etc) and mastercam 10 or better (for symmetry issues) and let them scan the one and cut back the rest. cost you a couple hundred dollars in most cases - or more if the shop has to cut a jig for an olds head which is most likely - almost no race teams run rockets.
once you get this done if the edelbrock intake is still around all you need is the performer series - no small block is going to spin fast enough to exceed that capability and still be streetable.
I think if you use BBO heads on the 350 the only edelbrock intake that fits is the performer rpm but I could be wrong.
August 1st, 2016, 01:35 PM
#4
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Join Date: Apr 2007
Location: CNJ
Posts: 279
^quaddriver, way to be a downer, huh?
I think you are a bit overboard for a street motor, it is MORE than doable, and without significant money and machine work on a good running motor. It all depends the power he wants to make, and a tame highway cruiser isn't in racecar territory either...
Cpriester123, a good set of stock heads, like 4,5,6,7,or 7a heads will work for you, especially the big valve variety. The important thing is knowing what pistons you have in it. Don't be too surprised if you need to mill the deck (or run a costly thin head gasket) because those replacement pistons sit .030 or more down the hole.
Let see what is in this motor before we dig too deep into plans. In your other thread you said you have one #6 and one #8, the 6's would be a good head, and you already have one. With decent compression and a decent cam, more power is attainable and quite streetable.
I think you are a bit overboard for a street motor, it is MORE than doable, and without significant money and machine work on a good running motor. It all depends the power he wants to make, and a tame highway cruiser isn't in racecar territory either...
Cpriester123, a good set of stock heads, like 4,5,6,7,or 7a heads will work for you, especially the big valve variety. The important thing is knowing what pistons you have in it. Don't be too surprised if you need to mill the deck (or run a costly thin head gasket) because those replacement pistons sit .030 or more down the hole.
Let see what is in this motor before we dig too deep into plans. In your other thread you said you have one #6 and one #8, the 6's would be a good head, and you already have one. With decent compression and a decent cam, more power is attainable and quite streetable.
August 1st, 2016, 03:01 PM
#5
Connoisseur d'Junque
Join Date: Sep 2010
Location: The Hudson Valley
Posts: 21,183
There are so many threads on here about increasing power to the SBO that even trying to list them would be ridiculous.
Just look through the "Small Blocks" section.
Also check out the "Home Porting" thread.
As for Edelbrock heads, they are fine, but the ProComps are much cheaper, and work great with a little machine work. There are several threads on here about that, as well.
When you settle on a desired head/valve size/lift and compression configuration, then ask Mark (CutlassEFI) for advice on cam grinds.
- Eric
Just look through the "Small Blocks" section.
Also check out the "Home Porting" thread.
As for Edelbrock heads, they are fine, but the ProComps are much cheaper, and work great with a little machine work. There are several threads on here about that, as well.
When you settle on a desired head/valve size/lift and compression configuration, then ask Mark (CutlassEFI) for advice on cam grinds.
- Eric
August 1st, 2016, 03:14 PM
#6
To put it simple. My big valves iron headed non ported 10 to 1 355 olds runs 12.60's. More than enough for the street. There is higher hp modern muscle but those guys don't know how to drive so it's easy pickings on the street. Relatively speaking atleast. I might as my build is brutally simple. There is nothing exotic about it or out of anyone's hands as far as parts and even work goes. Pretty Boring on paper. I also did it for about half the price most would pay to get the same performance but i guess thats unique to me i have a way of scoring deals and bartering for stuff. But i do it to show guys how simple it really is and if i can do it anyone can.
Last edited by coppercutlass; August 1st, 2016 at 05:27 PM.
August 1st, 2016, 04:13 PM
#7
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Thread Starter
Join Date: May 2016
Location: Walterboro, South Carolina
Posts: 197
^quaddriver, way to be a downer, huh?
I think you are a bit overboard for a street motor, it is MORE than doable, and without significant money and machine work on a good running motor. It all depends the power he wants to make, and a tame highway cruiser isn't in racecar territory either...
Cpriester123, a good set of stock heads, like 4,5,6,7,or 7a heads will work for you, especially the big valve variety. The important thing is knowing what pistons you have in it. Don't be too surprised if you need to mill the deck (or run a costly thin head gasket) because those replacement pistons sit .030 or more down the hole.
Let see what is in this motor before we dig too deep into plans. In your other thread you said you have one #6 and one #8, the 6's would be a good head, and you already have one. With decent compression and a decent cam, more power is attainable and quite streetable.
I think you are a bit overboard for a street motor, it is MORE than doable, and without significant money and machine work on a good running motor. It all depends the power he wants to make, and a tame highway cruiser isn't in racecar territory either...
Cpriester123, a good set of stock heads, like 4,5,6,7,or 7a heads will work for you, especially the big valve variety. The important thing is knowing what pistons you have in it. Don't be too surprised if you need to mill the deck (or run a costly thin head gasket) because those replacement pistons sit .030 or more down the hole.
Let see what is in this motor before we dig too deep into plans. In your other thread you said you have one #6 and one #8, the 6's would be a good head, and you already have one. With decent compression and a decent cam, more power is attainable and quite streetable.
August 1st, 2016, 04:14 PM
#8
Registered User
Thread Starter
Join Date: May 2016
Location: Walterboro, South Carolina
Posts: 197
There are so many threads on here about increasing power to the SBO that even trying to list them would be ridiculous.
Just look through the "Small Blocks" section.
Also check out the "Home Porting" thread.
As for Edelbrock heads, they are fine, but the ProComps are much cheaper, and work great with a little machine work. There are several threads on here about that, as well.
When you settle on a desired head/valve size/lift and compression configuration, then ask Mark (CutlassEFI) for advice on cam grinds.
- Eric
Just look through the "Small Blocks" section.
Also check out the "Home Porting" thread.
As for Edelbrock heads, they are fine, but the ProComps are much cheaper, and work great with a little machine work. There are several threads on here about that, as well.
When you settle on a desired head/valve size/lift and compression configuration, then ask Mark (CutlassEFI) for advice on cam grinds.
- Eric
August 1st, 2016, 05:21 PM
#9
-#6 heads (66cc)
-Performer RPM Intake (came with core motor)
-750 Cfm Quick fuel Slayer- #80p/#82sec
-Comp xe 268
-5.8 CC dish Speed Pros (.020) in the hole
-Proform distributor (came with core motor), 36* advance
-Crankshaft machined/balanced
- Long tube Hedman headers->x pipe->magna flow cats->40 series flowmasters 2.25” system
-All told cost me about 3,100 bucks. Have been driving it for a year, after finding the right harmony regarding the carb/timing it has never given me a single issue and I really couldn’t be happier with the performance.
What I would’ve built if I wasn’t buying a house, building this motor and fixing the AC on the delta all at the same time?
-Same as about save for:
-Ported heads with big block valves
-Hydraulic roller
-Probe pistons **Ordered these couldn’t take the run around from the manufacturer any longer
-I suggest reading this book:
https://www.amazon.com/Oldsmobile-V-...=oldsmobile+v8
You'll get some great insight from this site and the members; I only am siting someone specific because he has been an excellent Motor mentor to me, PM 80Rocket
August 1st, 2016, 09:36 PM
#12
4 Barrels of Laughs
Join Date: Jun 2016
Location: I moved to pittsburgh so I can be near Primantis
Posts: 405
August 2nd, 2016, 06:18 AM
#13
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Join Date: Apr 2007
Location: CNJ
Posts: 279
I'm just saying at the stock type idle cruiser level, stock heads will do fine.
Hell, on a small block, you can always go flat tops and BB heads or cut the hell out of them, talk about a port job, better than any grinding will do for you. That's the route I went on my 403.
Hell, on a small block, you can always go flat tops and BB heads or cut the hell out of them, talk about a port job, better than any grinding will do for you. That's the route I went on my 403.
August 2nd, 2016, 10:21 AM
#14
I think being realistic is giving real world results instead of hearsay . My heads just have big valves. Guys have gone plenty fast with small valves. Including myself. i ran 13.8's with a stock headed and i mean stock down to the valve springs #7a heads and a stock 73 350 with a towing cam.
August 2nd, 2016, 10:49 AM
#15
4 Barrels of Laughs
Join Date: Jun 2016
Location: I moved to pittsburgh so I can be near Primantis
Posts: 405
I think being realistic is giving real world results instead of hearsay . My heads just have big valves. Guys have gone plenty fast with small valves. Including myself. i ran 13.8's with a stock headed and i mean stock down to the valve springs #7a heads and a stock 73 350 with a towing cam.
August 2nd, 2016, 01:17 PM
#16
Beer Connoisseur
Join Date: Aug 2008
Location: Daly City, California
Posts: 2,091
IMO don't waste money on the small block, if you want street able power go with big block.
I have dumped a lot of money into my 350. Big valves, porting, all the goodies and still would get smoked by my wife in my chevelle which at that time had a decent budget build 383 in it
455 is worth of building to make a nice cruiser, but IMO 350 is a waste of money if you are looking for power.
I know everybody is gonna jump and crucify me, but this is real world experience.
Anyway my build is below, this was my first Olds build, needless to say compared to my SBC builds this was a major disappointment. It had more power and all but not what I expected for the money spent.
Pistons are SpeedPro 6cc dish .010 in the block
Reconditioned rods, crank turned and chamfered.
Heads are #6, big block valves Ferrea, 4 angle valve job, fully ported, crossover plugged, exhaust divider welded, milled .030, Lunati springs, Comp roller rockers.
Camshaft Lunati custom grind
225/231@.050, with .512/.517 lift. 108 LSA, advanced 3 degrees.
Performer RPM, milled and port matched
Hughes 2500 stall torque converter.
Hooker Ceramic Coated headers.
MSD Ready to Run Distributor
Street Avenger 670cfm carb
TCI High torque starter,
3.42 gears.
I have dumped a lot of money into my 350. Big valves, porting, all the goodies and still would get smoked by my wife in my chevelle which at that time had a decent budget build 383 in it
455 is worth of building to make a nice cruiser, but IMO 350 is a waste of money if you are looking for power.
I know everybody is gonna jump and crucify me, but this is real world experience.
Anyway my build is below, this was my first Olds build, needless to say compared to my SBC builds this was a major disappointment. It had more power and all but not what I expected for the money spent.
Pistons are SpeedPro 6cc dish .010 in the block
Reconditioned rods, crank turned and chamfered.
Heads are #6, big block valves Ferrea, 4 angle valve job, fully ported, crossover plugged, exhaust divider welded, milled .030, Lunati springs, Comp roller rockers.
Camshaft Lunati custom grind
225/231@.050, with .512/.517 lift. 108 LSA, advanced 3 degrees.
Performer RPM, milled and port matched
Hughes 2500 stall torque converter.
Hooker Ceramic Coated headers.
MSD Ready to Run Distributor
Street Avenger 670cfm carb
TCI High torque starter,
3.42 gears.
Last edited by 70cutty; August 2nd, 2016 at 01:21 PM.
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