Hello well first I have a 85 Iroc with a 305 TPI auto. Engine is pretty much stock. Just turned 70,000 miles. Has the stock 2.77 rearend. have a set of headers, ypipe, and 3" flowmaster catback setup to put on the car that i just took off the last car I parted out, just havent gotten around to putting it on. Also have a T5 trans and all linkage but it wont get in the car till summer.

My main question is what kind of heads would People suggest and know to work with a 305 TPI engine?? I keep being told go with alum Vortec heads but they cost about $500 and I can not afford that at all. Any ideas to raise about 20-40 HP preferred bold on as I dont want to build an engine.
Please Let me know with any ideas.
Thanks Brian

 

a rear would do wonders for your acceleration, although i dont think you will be making and more power (maybe to the wheels)? do you have k&n filters? they help a little. 500 too expensive for heads? youre obviously not ready for heads yet then. also you said bolt on...heads are not that easy to install if you are not experienced. just save up and do a 350 swap but seriously, i dont really know of any cheap upgrades that add a lot of hp, unless you wanna start gutting some of that tpi stuff.

 

Yes I do have k/n filters. Heads in my view are easy. Yes im young but trust me I know how to build an engine put it in and make it run and all that fun stuff. Built a 76 Corvette from ground up.
Looking for a cheaper set of heads like a couple hundred, or just some small mods to make it a little faster. I really dont want a huge change as I get really good gas milage and this is my daily driver.

 

Runners with a better intake manifold [both ported] will add around 20 hp.

 

oh ok. when you said bolt ons, combined with saying you dont wanna do anything complicated like building an engine, i figured you had no experience. get gears or a cam depending on what you have already and port your intake you already have.

 

NAWS works wonders or a assload of japan stickers and a wing

 

Port your heads. They are actually pretty decent heads, and the factory castings are bad enough that some home porting will make large gains. I picked up a set of 9 carbide cutters for $35 on ebay, and a port and polish kit by Standard Abrasives for another $40. You can't buy heads for a couple hundred dollars that will bolt on with zero work and be better than what you have.

 

i would start with easy bolt ons first your lucky and have an 85 they were the higher hp 305's 215hp which ran about 15 flat stock in the 1/4... try the headers, catback. then go to porting your plentum and installing a set of slp runners. while the upper intakes all off put on an afpr. i would also add a tb air foil and bypass the coolant to the tb. then you could try some weight reduction mods. remove your ac crap and all your smog stuff if your area allows it. as for the rear. i would definitly be switching to a set of 3:42 gears. they seem to be about perfect for mild auto tpi's. then also get some sort of sticky drag radial. with all that i then put you at..... oh i sat around 14.2-14.3 with good conditions

 

Do some searches for 305 stuff, pay attention to the name SMURFN' Z28.

His is coming together quite well. Its a 85 5spd car that he has been working on and its responding quite well. Not a lot of money into, just a lot of thought :-)

Ful exhaust(like u mentioned u have) and good port work to the intkae and some 1.6 rockers.

Look for free upgrages/mods too, lots of info under that topic as well.

By the way we have a NW IN/ chicago Suburb board here under regionals, 100+ of us hang there and have get togethers, track rentals, etc.

later
Jeremy

 

yea, like descreening your maf and cutting out the air inlets near the filters. also, i think you can get some l98 corvette heads for your motor and they would be the almost maximum flow for a 305. i dont know if its true or not, but its what ive heard and im sure you could find them for a decent price.

 

You might want to look for a performance chip as well such as Hypertech,TPIS,Jet,Fast chips, or even a custom prom.

 

I wouldnt descreen a MAF unless u plan on rebuilding the MAF tables in the prom personally.

Cheapest bang for the buck upgrade would be head over to the prom board and read the "Tuning Guide" Rbob and I have put together and start from there.

I wouldnt rate HyperTech, TPIS or anyone else any where near what u can do with your own car yourself for less investment than you will pay for one of their "chips".

I've compared them side by side, u want to tell me your car runs better or idles better with them and I'll laugh at you :-)

later
Jeremy

 

Learned about the chips the hard way.Shelled out $400 for a custom chip and ran it against a chip that Ed Maher burnt for me>Look in sig to find out which chip won

 

who is this ed maher you speak of?

 

K&ns with gutted airbox, slp runners port matched to your plenum, even with a stock base manifold will compliment your exhaust well and make some noticible midrange and top end power.

 

former moderator & a good friend

 

I never really got into chips that much so this may be a dumb question but what are the advantages of burning your own chip.

 

How much would a nice rear cost? I have a 89 stock(as far as i know) RS 305 TBI

My car feels slow as hell a lot of times

 

it's "slow as hell" because it's a 305 tbi. my old car had the LO3 till it caught fire and i dumped it, now my new IROC has has an l98 and you wouldnt believe the difference

 

it says in your sig that you have a xe256 cam.... if i recall that is a big block ford cam.....

 

adj fuel pressure reg
slp air foil
accel intake runners
id get a cam before heads
port match everything
gears.
the gears would be over kill for your goal though. it'l get you et that will have mustang GTs looking out.

 

You can bore out the lifter valley for ford lobes it actually makes life easier on the valve train and adds a few hp, but you would need a custom cam.

 

exhaust, ignition, remove the air baffles in the air cleaner, an airfoil may help a little too...

GET RID OF THOSE GEARS! i have an 85 305 TPI in my car and i had 2.73s, and it BLEW!!! get something up near 3.27 or higher, but i wouldn't go to 3.73 due to the the TPI running out of breath at 4500-ish RPMS. also, put posi in there too. A Borg Warner 9-bolt from an 89 or later car would be great; i paid $225 for one at a swap meet and it came with working posi, 3.27 gears, and the disc brakes with aluminum calipers.

hope my info was actually helpful lol