Hey guys. heres my question. I am gonna be building a 350 block. I need a mid 80's and up block to make the swap legal I know, but if I took everything off my lil 305 and slapped it on the new 350, would it still pass the sniffer. It won't be anything too wild, a ZZ4 cam maybe or something else, dual plane EGR intake, headers with oxy fittings and AIR injection, 3" catback with a highflow cat or something to that end.
Basically it will be a 350 wearing 305 clothing, save for some bigger secondary rods for the Q-jet and a bigger fuel pump. Is it possible>?>?> Will it pass? if I smog it, will they smog it by the vin? Does a 350 make more pollutants than a 305?

Also, how should I go about computer programing? I will need a new chip to run the car and compensate for the differences in fuel and such. Does Ed Wright do this sort of thing or anyone else? I don't think a 350 getting 305 fuel levels would be too happy. Well thanks guys!

Will

 

it can be done...but i live in NJ and you live in CA so good luck man

 

A little more detail? Anyone know someone who has done it?> I want to know if a 350 will not accept 305 smog plubming and so on. Why GM never made a carbed 350 in the first place is beyond me. But from GMPP, what I understand is that everything off that 305 can be bolted onto the new HP 350, as it comes with nothing to do with smog, yet is smog legal in Cali?//////

Thanks guys

Will

 

I am down guys! Let me know whats up. I might not be able to get time off work as I just started about 2 months ago, and my probationary period will be ending sometime in early Jan, and I dunno if they would be too keen on letting me have a day off so soon, but I will check on that. Also, you might consider posting this in the Events and Cruise Spots forum, as that is kind of the Bay Area GTG place, we have a lot of guys that check that forum out. Anyway, I am from SF, so anywhere in the Bay is fine. Hope you guys don't mind a 3rd gen taggin along

Hope to make some new friends. If I can get to some of my buddies in time, I can bring maybe 5 cars with me, or more. I have to check with them! TTT guys

Will

 

Yes you can replace a 305 with a 350, because they are both small block chevrolet engines. Everything external on the 305 will bolt onto the 350. The computer barely controls anything on a carb car, so you wont need a new chip. A 350 can put out more pollutants than a 305, but you shouldnt have to worry about it. My car just passed the sniffer easily, even tho the VIN says its a 305.

 

I replaced my 305 with a 350. Every thing bolted up from the 305. I had no problem with emission testing. My car has TPI tho. I don't see why it would not work. I would think you would only have to rejet the carb. Also be carefull with the cam because it will change the emission and engine vacuum. There are cam companys that make cams to work with the computer systems so you don't have to change the chip. Call some and they can tell you what works best.

 

Where I live they have a Hot rod class for E-testing If you can get a letter from gm thats says a 350 never came in this car they will test it by 1980 standards even if its a 86 Z28 so you might want to see if you state has a Hot rod class

 

I read that two people swapped from a 305 to a 350 and still passed smog i want to do the same thing and also pass emissions, where should i order the 350 motor from? What part number is it? All the 350 tbi motors i find say they are for truck or suv does that matter? I have a 91 camaro rs with a 305 tbi from my reasearch everything should bolt up correct? Im just nervous that i might order the wrong motor, any suggestions? Is there anything else i should look out for? This will be my first motor swap i repair most issues with my cars and im mechanically enclined but im kind of nervous because a 350 motor is a good 1500$-2k$ and i dont want to mess it up.

 

I don't know if your question has been answered yet or not I just got on this site anyways I live in Bakersfield California and I used to build Exhaust systems and of course I didn't do it but the guy i worked for did smogging. Talking to a friend of mine 5 minutes ago who owns the smog shop Told me "yes you can swap out at 305 for 350 AND you must transfer all of the 350 smog equipment that is all you have to do. I hope this helps ya 👍