Pontiac 350 Performance upgrades

[Joe71]

I’ve got a 1971 350 motor that I want to get some more power out of right now, it’s already got duel exhaust but that’s really the only “performance” system on it. I’d like to get a new intake manifold and maybe new exhaust heads but i don’t know where to look. I don’t have boat loads of money to throw at it and I still need it to be a daily driver. So no turbos or superchargers. I’m happy to hear any suggestions. (Go check out my baby too. The names LuLu) 

[Frosty]

Hi Joe - welcome fellow Meeechigander to FP.

The Pontiac 350, like its 326/389/400/455 cousins responds well to the basic engine upgrades. It depends on how much you are willing to spend and how much down time you can endure. Things I am suggesting won't necessarily break the bank but they are not free either. 

Since you said 350 Lemans I will assume right off the bat that this is a 2-bbl intake and carb. You can search Craigslist, eBay, and local swap meets for a used iron Pontiac 4-bbl manifold and Rochester carb. Top price I'd pay for a manifold is $100-150. You can find it cheaper if you look around. As for a Rochester carb, you want the Buick-Olds-Pontiac style that has the gas line comes in from the front. Chevy versions come in from the side. I'd spend $50 for one and then buy a rebuild kit. If you need a new full line, you can get one from National Parts Depot in Canton.

For now, I'm guessing that new or used heads are out of the question. However, if the engine has never been touched, your motor could stand to have a new cam and lifters installed. I would also take the time to remove the heads, have new hardened valve guides installed and have a triple angle valve job done to it and some mild port and polishing / gasket matching done to it to help air flow. I would also inspect the stock stamped rockers and perhaps replace them. Mine are a stamped roller rocker for longevity.

I would consider upgrading my distributor to breakerless ignition and do away with points and the dwell meter. A Pertrronix III Ignition kit or a new breakerless stock-locking distributor will work. A used GM HEI unit will also work.

New distributor cap, rotor, plug wires, and properly gapped spark plugs are always a good thing. 

Assuming the swap meet season isn't a total bust this spring, in addition to Craigslist and such, ta good place to find parts is the Bearing Burns Swap Meet which is currently scheduled for Sunday, May 3 2020 at the Knights of Columbus Picnic Grounds in Shelby Township.

All this is relatively inexpensive. I'd guess it's less that $2000 in parts and machine shop labor. However, it will require down time.

Is this what you were looking for?

[Joe71]

Yes this is perfect. Thank for the advice!

[JUSTA6]

4 hours ago, Frosty said:

Hi Joe - welcome fellow Meeechigander to FP.

The Pontiac 350, like its 326/389/400/455 cousins responds well to the basic engine upgrades. It depends on how much you are willing to spend and how much down time you can endure. Things I am suggesting won't necessarily break the bank but they are not free either. 

Since you said 350 Lemans I will assume right off the bat that this is a 2-bbl intake and carb. You can search Craigslist, eBay, and local swap meets for a used iron Pontiac 4-bbl manifold and Rochester carb. Top price I'd pay for a manifold is $100-150. You can find it cheaper if you look around. As for a Rochester carb, you want the Buick-Olds-Pontiac style that has the gas line comes in from the front. Chevy versions come in from the side. I'd spend $50 for one and then buy a rebuild kit. If you need a new full line, you can get one from National Parts Depot in Canton.

For now, I'm guessing that new or used heads are out of the question. However, if the engine has never been touched, your motor could stand to have a new cam and lifters installed. I would also take the time to remove the heads, have new hardened valve guides installed and have a triple angle valve job done to it and some mild port and polishing / gasket matching done to it to help air flow. I would also inspect the stock stamped rockers and perhaps replace them. Mine are a stamped roller rocker for longevity.

I would consider upgrading my distributor to breakerless ignition and do away with points and the dwell meter. A Pertrronix III Ignition kit or a new breakerless stock-locking distributor will work. A used GM HEI unit will also work.

New distributor cap, rotor, plug wires, and properly gapped spark plugs are always a good thing. 

Assuming the swap meet season isn't a total bust this spring, in addition to Craigslist and such, ta good place to find parts is the Bearing Burns Swap Meet which is currently scheduled for Sunday, May 3 2020 at the Knights of Columbus Picnic Grounds in Shelby Township.

All this is relatively inexpensive. I'd guess it's less that $2000 in parts and machine shop labor. However, it will require down time.

Is this what you were looking for?

Agree with everything Frosty is suggesting, but the Pertronix 111 is overkill.  This is pretty much full on racecar.  Will also require MSD ignition upgrades and more $$$. Already getting bored with the TV and the whole Corona situation, I JUSTA spend a good deal of time researching and went with the Pertronix 1 system.  Doubles the spark input and can use your stock coil/system.   Here's the link to check out what you are looking for.  Customer service was extremely helpful and could have talked with him all day.  He was bored tooo as things were dead around there too. Good luck and great to see another Mitten member here.  Keep June open to attend the Widetracker Spring Dustoff and meet up with a bunch of us FP  Michiganers.

https://pertronix.com/pertronix-1181ls-ignitor-delco-lobe-sensor-8-cyl.html#product_tabs_additional_tabbed

Edited March 26, 2020 by JUSTA6

[Frosty]

I forget to mention Facebook Marketplace is another local source to shop online for used parts.

SInce you plan to pull the manifold, now would be a good time to inspect/replace the thermostat, check and inspect your belts, flush/fill your coolant, brakes, power steering fluids too.