how much more power can I get from my 72 350 2 barrel by swapping to a stock 4 barrel intake

 

15%. Iirc the 2bbl was rated at 160hp the 4bbl at 180 hp....

 

160 to 180 is a 12.5% increase . A good power timing and a set o dual exhaust will probably add that much.

 

the engine is getting replaced but I want a lil more out of it in the meantime

 

If you don't have a carb or intake, get one of the carbs I mentioned with the Performer RPM intake. The Street Demon 750 or Qjet will run OK, especially a late 70's 350 or 403 800 cfm Qjet being an emissions carb. Then when you build your 403, just send it to someone like Everyday Performance to run properly with the bigger cam, displacement and higher compression. The Street Demon 750 has tuning kits and should run fine with cam you are planning out box but may need some dialing in with either motor to be ideal.

 

The 2bbl single exhaust engine was rated 160 HP, with duals that increased to 175 hp. 4bbl single exhaust was rated 180 hp and with duals increased to 200 hp.

 

Why not a regular Performer? Is the RPM better in the street?

 

The OP has a heavy 1972 D88 with a 350 and likely low numerical gears. This car needs an engine built for low end torque in traffic, not high RPM HP. The base Performer will be a better choice than an RPM. A Qjet will be a better carb choice.

 

No, he has 3.73 gears and a 2000 stall, according to his other post. He is also planning on a .224/.224 .501/.501 Comp Cam in a 403 with early 350 heads. The Performer is OK and works fine with stock or near stock motors but he is planning a fairly decent 403, so a RPM is fine in the now AND better in the near future. Of course he will need electric choke and need to use block off plugs in the heads with the RPM. If he is planning on driving in sub freezing temps often, the Performer is a better choice. I agree, get a late 70's 350 or 403 800 cfm Qjet. It will be near perfect stock with just a rebuild but will need a recalibration with his future plans.

 

Some guys use it on nearly everything but depends on where you live climate wise and your car's intentions.

 

i might build the 350 and the 403

 

Ah, I didn't connect the multiple posts. In that case, if OP is buying an aftermarket intake, I would agree to get the RPM.

I WOULD suggest BBO heads on the 403, however...

 

ok guys to clear this 1 up I'm building a 403 for the car

it currently has the 350 with a mild cam the new stall an gears wont go in till the new engine

 

Decide whether you want a Performer or RPM intake for your 403, either will work with your current 350 just fine. The 403 or any late 70's 800 cfm Qjet will work with your current motor.