4.3 to 305

[barebones 1500]

did a little research on the 305 to the 350. the 350 is definitely a better performance motor with a large list of aftermarket parts to choose from, but since i am not building a big motor i stuck to stock. the 305 was built as a standard motor to produce a fair amount of power for almost any car or truck it was put into where as the 350 was built as a better performance option. not trying to start a big debate or say that the 350 isn't a great motor but it is a bit more than i need. i think that the 305 will be plenty of power for what i do with it. i also found that if you swap the intake and heads you can get a 305 to put out 400 hp and it is fairly cheap to do. all in all, i think a stock 305 will be fine for me for now but if i find a good deal on a 350 then that will go in. if i later decide to build a motor i will go with a 350 hands down.

edit: upon further research, the claim of a 400 hp 305 might be a little far fetched, but nothing that says it is a bad motor. it is hard to tell whether people are just going with the old " 305, that is a boat anchor" adage or there is any weight behind their claim, good or bad. another question came up regarding gas mileage. i know i want as fuel efficient motor i can get there are a lot of mixed reviews. i am thinking of doing the e-fan swap and an electric water pump to help improve MPGs but which motor would benefit the most? i think the 305 would just cause it is smaller but if it really is a hog compared to the 350, then i think the 350 would get more of a benefit. anyone have input on these?

 

[Swims350]

305's are alright, some are good some are bad same for 350's. I got a nice 305 in the 85 mcss I sold my BIL and it's quick and it's stock. Almost all of the performance parts and add ons for a 350 will work on a 305 as well.

 

[RHamill]

I know a guy that drives a 1994 GMC Sport z71, so its a SCLB half ton with the W/T grille, extra z71 stickers, a 4.3L, 3.73 gears and 4 wheel drive. He was turning 305/70r15's on steel 15x9 wheels, he beat the living hell out of that truck, covering it in mud and all that, with just a stock 4.3!, so whatever you are doing with a 305 should be fine, I had an 87' Grand Prix with a 305 suited with a 4 BBL carb, and it ran great and had enough power for me at the time, if I still had that car I would put a 350 in it however, or at least swapped a 4.10 rearend in it and see what that did to the 305.

Good Luck anyways!


Here's that guys truck I was talking about, All of this with a 4.3!

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I had more than 1 picture of my car at one time.. what the hell, but I do have some videos floating around on youtube with the stock exhaust with a leak in it..

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[1Kurgan1]

I know you are looking away from the 350, but I just want to say this. If you are looking at used motors then there most likely isn't going to be a difference in price between a 350 and a 305, it's an older motor, people don't charge for displacement, I even see early 90's 454's going for $200. If your building it new on the other hand, then I'm not completely sure. Either way, honestly the 305 nor the 350 are powerhouses stock in TBI form, so I'd get what you can find for a good price, if thats a 305 get it, but if its a 350 get it.

 

[Swims350]

I want a big block for $200 sign me up. LOL

 

[jcro61]

454 are atleast 750 around here non running. well running are like 1500

 

[barebones 1500]

the 4.3 is definitely a strong little motor, it has always done what i wanted it to do whether it liked it or not. i am not looking for a huge power house of a motor but something that has a little more power than the 4.3 and decent gas mileage, so i think the 305 will be fine. talked to the wife about it to get the green light for the swap and she isn't completely on board. she wants me to buy a new truck but i don't want a car payment plus the spike for insurance cause i will have to have full coverage, add in the fact that i am under 25 and i will be paying an arm and a leg. but the plan right now is I'm going to save my money over the winter and look into both options and if i find a new truck that i can afford i will get it but if nothing is out there then i will do the swap. kinda sucks cause i was starting to look forward to the swap. i guess i got a yellow light as kinda a happy medium

 

[jcro61]

Why not swap in a newer 4.3 with vortec heads if you just want a little bump.

 

[barebones 1500]

that was my original idea because they are in several vehicles and are fairly common. i decided against that because this is my DD and getting the wiring right would take more time than i have. where as swapping in a similar motor( meaning a 305 or 350 will drop in with little mods to the truck or wiring) would be much easier and if i get on it then i could get it done in like a day/ day and a half which is a much better time frame for me. plus i am not sure how to really go about wiring the truck for a motor that is much newer. also i think i will get about the same gas mileage with the 305 or even better because i do plan on kinda rebuilding it first plus the possible e-fan swap and e-water pump i would like to do if i have the funds

 

[barebones 1500]

talked to my brother, a guy he works has a 350 that he will let go for $150. just gotta wait and see what all comes with it. i think it has a carb but i think i will swap it to tbi, all i got to do is put a throttle body on it right?