hellow everyone... help my make my terd of a car worth driving, i have a 1986 IROC with a 305 TPI, i have SLP runners and HOOKER cat- back but no differance to my performance. WTF

i need advice to make my car run into the mid 13's. from what my friends said, a 5-speed and 1.6 rockers will make me run into the LX mustang territory

do i need valve train work??? like what?

 

also i will do emmitions and a/c delete.

 

id also like to know what you guys would recomend for are 86 TPI's.... first thing id suspect needing to be changed is are cam beacause we got a crappy *** cam in 86 giving us 190hp and the 85 version put out 215hp do to a better cam but are 86 did have a bit more torque.

 

A 15.9 is not good for any TPI car of any year regardless of the tranny behind it....

No offense of course..but here is what I did to my 305 and it runs very well...cold air intake from SLP,ported maf,air foil,ported plenum,AFPR set @ 47 psi or so,timing to 12',msd ignition,blue max wires,accel coil,...vigilante converter,rebuilt tranny with trans-go shift kit,aluminum driveshaft,boxed control arms/panhard rod,straight pipe/flowmasters...I feel like the car is a very solid low 14 second car...have not run it yet at the track so not certain,but I held my own quite well against low 14/high 13 sec cars...with headers and gears I feel I could run a solid 13 with traction,in good weather...SLP runners are really useless on a rather stock 305 ..notice all of my mods are in groups...the intake needs to be done as a whole or there is bottlenecks..as the ignition...the after market runners only work if everything BEFORE them is done right,,TPI is all about velocity...plus I think the intake ducting on pre-88 cars is horribble..like a box or something..even upgrading to the stock elbows from the 88-up cars is an improvement..only the firebird was like this...the camaro was better hence its 5hp higher rating.
Don't get caught up on the non-sense that 305 needs heads and cams to run 13's...they just need good suspension mods for traction and balanced mods on intake/exhaust...

 

Sorry didn't see that you needed a new posi...that would explain the times being a little off...so with that fixed your mid 15's which is about right...

 

so were would fabing up a new cold air and a holly t/b for the intake, and for exaust i would do HOOKER long tubes with off-road y-pipe put my car????

with a new posi....

 

no one will believe this but in the real world, stock 305 tpi automatic cars run mid 15s. i have seen many at the track and mine was around the mid 15s when it was stock, thats jsut how they are. a buddy of mine has a mint 85 iroc and he ran a 15.9. the car runs fine, there is nothign wrong with it at all, thats just what it runs, period.

anyway, the runners are not necessary for your combination. the hooker cat back is a step in the right direction. headers will help you alot as well. set the timing to about 8 or 10 degrees advance (with the set timing connector disconnected mind you) and take the baffles out of the air boxes. then headers and cam should be the next step. as you will read if you do a search 86 was teh first year for the peanut cam. with only the headers and cam in my sig my car went 14.8 @94mph. the ET is so so but that is a pretty healthy trap speed for a cam and exhaust 305. for the rest of the mods see my sig, once i get stuff with my chip ironed out i am lookin to go in the high 13s.

if you do a search you will find lots of fast 305 cars. all you need is
1 headers and exhaust
2 mild cam
3 3.23 or 3.42 gears
4 and a decent flowing set of heads (ported stockers or otherwise)
5 a mildly ported intake plenum and base

your stock throttle body, stock injectors, and stock fuel pump are plenty to get you into the 13s. i dont konw what your goal for performance is but 305s can run hard dont get discouraged. again just do a search and check out my sig and you will have all the info you need to get your LB9 car into LT1 territory

 

also the 15.9 quarter mile time was with a 2.4 short time!!!

 

A cold air kit is good for a tenth or two,but remember to port your plenum,mod maf if you want,it does help a little,for the TB just put an airfoil in the 48 mm you have..52mm or bigger is useless for a rather stock 305...do the intake as a whole...then upgrade your ignition as awhole..as well as fuel pressure(you will have to play with it a little every car is diffrent)as your timing...mine got away with 12' but again some are diffrent...that will be worth a couple tenths...I would just get a nice set of shorty headers for the 305 at 1 5/8...
It will give you nice torque and horsepower increase along with a straight pipe and flows(or your favorite brand exhaust) and you have a few more tenths knocked off...
Get a nice converter for your auto not real big,maybe in the 2000-2400 range,and a good set of drag radials...that could be good for at least a few tenths..
And most important,and the proof is in the post above,you can make power but if you don't get it to the ground its useless...I can't tell you how much my T/A improved with a good set of subframe connectors,boxed panhard rod/and control arms...you can also do relocation brakets as well...so with these mods you can knock off a solid second or more,and with that posi fixed with a slight gear upgrade, you could be flirting with/perhaps high 13's without going into the bottom end of the motor( cam swap ect.)..which with how old our cars are getting,you want to be real careful with...you can stick a cam in and it will give a nice increase as the stocker is a joke...but everything before and after it should be done right first to get max gains from it....