TBIFirebird305

Hey everyone.
I hate to sound pushy but id like any and all input relatively quickly because ive come across a good deal on a set of HO 305 aluminum heads and an aluminum intake manifold that came off of a z28 camaro and I plan on buying them asap if all goes well. My question though is that I have a stock 305 tbi engine in my firebird, does switching to this HO aluminum set up give me noticable gains to go through swapping them out? And what more could I do to see better results.
Thanks for any input.

ATCFLYBOY02

iTrader: (1)

I'd say no more than 15-20 HP... Your not really gonna get any big gains out of a 305 bro...

TBIFirebird305

Aye man, I'm fully aware of the problems with the 305, in fact i never planned on buying one. When I bought my car I was told it had a 350 swap. i proved that wrong when I pulled the motor out of the car for a rebuild. I'm 17 and this is my first project car, I love cars and all my friends are in to them too so Its a great way to learn on this car before i get up to the big boys..haha So, I dont have much money, just looking for bolt ons here and there and these are 75 on craigslist so I was just wondering if they were worth the trouble of putting on.

KrazyFirst

If you still have the stock exhaust setup it will still boost power but not as much if you have a full exhaust. If you save up for a top end kit + exhaust kit, it would really wake the engine up. But for that kind of money you can just buy a good power making engine

Orr89RocZ

iTrader: (20)

Did they even make aluminum heads for 305's? I dont recall any being made. L98 vettes had aluminum heads in the late 80's but I am unware of any fbody motors with aluminum or any car/truck with aluminum.

What is the casting number?

heads alone will not gain much performance with the stock baby camshafts and factory intakes. You need to upgrade the cam. Some stock head castings are worth much more power over others, so depending on the head, you could see 30-40hp more on a larger cammed setup!

thomas1976

Never heard of any HO 305 aluminium heads, what is the casting #?
The LO3 (305 tbi) has already an aluminium intake manifold.
You need to add more information about your engine and plans.

TBIFirebird305

The car has a high flow cat and 2 3/4 flowmaster all the way back. If I get the heads id look into a new set of exhaust headers to have a full exhaust set up. I really would like a 350 tpi but I just dont know because I just rebuilt this engine so I know what ive got and I know its strong. If I go get another motor ill prob want to rebuild it so thats more money right there. But if it trully is the best thing to do...and yall arent being straight biased..haha I may just start saving.

TBIFirebird305

I dont have the casting numbers available unfortunatley. I do know that the lo3 came with aluminum intake but the one id get would fit the new heads ports. I do beleive that this set up did come on the z28...i could be wrong though.

TBIFirebird305

Does just the common lt1 cam swap perform enough to see a good gain with the right head setup

Orr89RocZ

iTrader: (20)

Depends on the original cam but I believe that TBI 305 has a tiny cam to begin with. LT1 swap is a cost effective cam and does show good results. Use that with new heads and possibly 1.6 rockers and it should noticeably pick up. I'd actually wouldnt be afraid tho to go to a aftermarket cam thats slightly bigger than the LT1... something like a 212/218 comp or lunati grind. Heads will need to be modded for the valve lift but that aint much money to do. Probably will need to take the used heads to the machine shop anyway for cleaning/inspection before running and I'd advise a mild resurface to the head deck. Mill .006" off or so just to ensure smooth deck for best gasket seal. While there, just install screw in studs and machine the guide bosses down abit.

It will need a tune to make it all work to its potential but it should be a stout little motor

Mild worked over 416 castings work well on 305's and even better are the 305 vortec heads you can find. Not very common but they are worth a good bit of power over stock 416's.

thomas1976

If you like shopping, buy them, otherwise learn about what you buy first and buy only what you need.

TBIFirebird305

Thats why im on here asking these questions man.

TBIFirebird305

Well, while I got yall here, how much do yall honestly believe I could get if I sold my 305 tbi stock with 1000 miles on a rebuild. Its dressed up a little and thats it. The only reason id sell it would to fund a 350 swap.

Orr89RocZ

iTrader: (20)

Not much... they arent real desirable and with LS motors going for cheap, its not a feasible swap. But theres always someone who may need to swap from a V6 to a V8 or replace their 305 for an application that doesnt need performance.... I'd say under a 1000 bucks, over 500... in that range. Doesnt sound good but I dont think it would sell any higher. My friends and I have had hard times selling good condition 350-355 rebuild motors

sofakingdom

iTrader: (1)

A used 305 isn't worth much... I've paid people to haul off stuff like that.

Don't count on getting more than $100 or so for it, in complete running ready-to-drop-in-and-drive condition. It goes down from there if anything is missing.