Just wanted to know what everyone has done to there 305's... I would like to know the parts and how much power it added and if taken to the track what times you running before and after the parts.....

 

Start with a dual-snorkel air cleaner. That's a solid 2 tenths and no loss of gas mileage.

 

First upgrade was to replace the 2.73 10 bolt rear end with a 3.27 9 bolt.

 

Went 3.42 myself. Will put a small hurt on gas mileage on the highway but not much.

 

I've tried both 3.23s and 3.42s. I'd say hold off until you've done more to the car, because you'll be changing gears once you're satisfied with your final engine combo, why change twice? Your engine as it is won't like 3.73s, and the main culprets are primarily the heads, secondarily the tiny cam, and thirdly the restrictive exhaust system and intake manifold.

 

2nd mod; build a 355 or larger, or purchase a crate motor to replace the 305.

 

well my 305 has some work done to it but just wanted to know what everyone else was doing...

 

Well back befor i swapped my 305 all i had was a good intake carb headers, duel exhaust, and a cold air intake (in the form of a hood scoop). The factory cam and unmodified lg4 heads were still in place. I never took it to the track but that think was a beast on the street. With a 5 speed trans and a 3.73 rear i could pretty easily peel out in 1st, 2nd, and chirp into third alittle bit. All of thats from a roll as well no power shifting or brake stands required to break loose.

 

ok , i got to get into this one. Im wondering the same thing as the topic starter. i got a 85 305 tpi 4spd auto(215hp 275tq, flowmaster, k&n filters, 3.23 gears and a shift kit). not sure about an engine swap yet but it may be in the works for a 350+. but im thinkin bout finding some aluminum heads off a vette somewhere , a mid sized cam, aluminum driveshaft and full exhaust, you know the cheap stuff. but the big thing im hearing is that the max rpm is just over 4500 because of the tpi intake setup and so restricting alot of power and airflow. i like the tpi setup so is it worth spending the money (about 500 each) for an aftermarket intake , runners and manifold?

 

It all really depends what you want from the car. Now that being said if all you want is a fun daily driver the 305 can do the job just fine and with items like the aluminum l-98 heads youll have a nice ride. So for daily driven cars i almost never recomend doing a motor swap as there really isnt much of a reason. Now if the motor were to get blown then ide say rather than swap in another 305 go for the 350 as its virtually the same motor. This also means any mods to the 305 will be able to be swapped over to the 350. Now a word on TPI that 4,500 max rpm estimate is based on a 350. The TPI set up was actually designed based on a 305s air flow data. Conciquently on 305s little gains will be realized with the addition of aftermarket runners and bases unless heavily modified. Now is TPI worth keeping again depends what you want from the car.

 

im just lookin for a little more gid'up. ive got an 02 with an ls6 that puts just under 400 to the ground and this little 200 horse 305 just doesnt do enough for me as is. so i just want the easies upgrades for the littles investment, and i think the upgrades i mentioned are the route to go. they will make my motor more efficient and take a way some weight which is all a good thing for power and mileage