Which one would be the better 1 st. Up grade? And what is the diff. In performace between holly 58 mm throttle body and a bbk? Beside the price lol I have an 86 305 tpi

 

both are fairly pointless at a stock setting honestly but, the runners are definetly a better upgrade for later on if nothing else.

 

58mm on a 305? You looking to SLOW your car down?

 

Forget those Mod's unless you are planning on doing some serious work later. Buy a nice set of headers and a cat-back, you will see more gains and it will benefit you even with your current stock setup. Trust me

 

Well I already have a cat back I am gettin headers as well, and I am also gettin slp intake system so I have about 400 dollers left so I needed to know what one would be a better up grade so what you guys are sayin that not one of those parts will be better then the stock tpi runners and stock throttle body and I'm also gettin hypertech performace chip to go in to the car. So what kind of work should I get done to it then???????

 

dont get a hypertech chip.

with the extra 400$ i would opt for a cam swap, something like a lt1 cam would definetly be more fun than the stock cam, then i'd probably buy a set of cheap 1.6 full roller rockers.

After that or instead of that i would pickup another tpi intake and port it out and siamese it and all that good stuff, then you can just install it in place of your stock 1 later on after the cam swap (after a cam headers and some free mods the porting will definetly be a huge help).

 

The larger TB's only help in the very high up rpms, or very modified motor. IMO that would be the very last thing I would get. You can get a better "bang" for your buck elsewhere in a mostly stock motor.

 

Save up that money for a set of heads and cam or something like that. The TPI on a 305 is not as much of a bottleneck as if it were on a 350. You will see miniscule gains if you poke around with the stock intake system. 58MM tb is out of the question though, that is way overkill. You only need to increase the amount of air coming in once you have a combo that needs more air than is getting put in. This is not the case for you right now, your air volume being taken in is adequate as of now.

 

You can put an LT1 cam or 1.6 rockers on the stock cam, but you cant do both on the stock heads. There isnt enough room in the valve springs.

 

If you spend over $300 for a 58 mm TB, and whatever amount for a "hypercrap" chip, use whatever money you have left to buy a good bullet to shoot yourself in the foot with. Seriously though, if you're just trying to decide between runners or a 58 mm TB, there's no question that the runners would be a better investment. I have to agree with GuitarJunki though, the TPI system isn't extremely restrictive on a 305 motor, so your money would be much better spent on a good cam, or more exhaust upgrades. You could also score a good used set of the corvette aluminum 113 casting heads for that $400 if you shop around a bit. Heads, cam, or exhaust stuff will definitely make a lot more difference than the other things.

 

Hell, with the amount of money he is looking to spend, on a 305 I vote for the best upgrade as a set of higher ratio gears. UNLESS of course, you have the optioned 3.42 gears, but you have to check the codes on the inside door. With a lack of other engine mods (heads, cam, increased bore and stroke), your engine is content with the amount of air you are giving it right now.

 

does anyone know of any after market headers that wil take those air lines for the air diverter valve. my stock headers have like al these metal airlins pribing into them and not sure if i can even replace them with new headers.

 

I'd spend the money on an MSD plug and play pro billet distributor, and a blaster coil.

Gears would be the best deal, though, if you don't already have them.

 

if you siamese the base intake. will it run ok on a 305 i thought that it might be to much for the 305 i am building a 305 now i was going to do that to the base but i figured it would kill my torque

 

For the best bang for the buck, I would put in a shift kit. I have one and would never go back.

 

Hooker Headers part number 2055.

 

i would go with a set of slp runners

SLP RUNNERS=bolt on horsepower

and a + is if you ever decide to upgrade to a bigger motor....you can swap the whole TPI setup onto it.....(you would just have to buy bigger injectors, and get a prom burnt)

but anyway, i would rather buy an upgrade that is "re-usable" EX: if u bought a cam for your 305, you wouldnt want to/ be able to use it in a 350....