I have a 1990 Camaro RS with the 305 TBI in it. I know the car runs like low 16's stock. I have been told that all my mods I have sitting around are really good for this motor. I would like an estimate on what I will run after I install

-Dynomax catback
-Catco cat
-1.6 Roller Rockers
-K&N open element
-Ultimate tbi mods

The car is a five speed. Thank you very much guys.

 

i would also get some sticky tires of some sort.

i would say that with those, and some sticky tires, you may be into the mid/low 15's...get ready to do some prom tuning though to get the optimal gain out of that stuff...it seems that the tbi motors don't really respond to mods well without tuning.

 

low 16's

 

High 15's

 

i guess i'm a little optimistic...but i think mid 15's would be obtainable if you could drive the crap out of the car!

 

Ok now add underdrive pullies and 3 degrees of timing advance to the combo and let me know what we come up with. Thanks

 

Not much of a difference...be careful with underdrive pullies they have been know to make cars discharge at idel. I am going to still say high 15's, until you get some better mods you wont see much difference. Id go with headers and a better intake manifold, then you should see some results. If you do get serious with the car ditch that tbi and go for a better intake.

 

How critical would a posi and 3.73's be?

 

What gears do you currently have?

 

3.08 open rear

 

You would notice a big difference on the low end. With 3.73's you would most likely drop .3 to .4 off your 1/4 times. You will loose a bit of high end, and your gas miliage will be worse. BTW what are you looking to run?

 

I was hoping to at least find a way into the 14's....think headers and y-pipe would do the trick?

 

Well....The stock exhaust manifolds really really suck on the L03. I would know I had an Lg4 a few years back. The intake manifold is the same story very restrictive. I think with headers a better intake manifold, Chip, 3.73 gears, and radials you will see very high 14's. I had an Lg4 with exhaust,headers,intake,filter, dual snorkel air cleaner setup,chip,gears, and radials and I ran a 14.9, and we all know L03 and Lg4 cars are very similar.

 

its gonna take different heads and camshaft to be able to get into the 14's with an LO3 along with the intake mani and exhaust parts mention'd along with some computer chip tuning.

 

It will depend on the tune of the car.

 

Even with good tuning, i dont see a stock headed LO3 hit anything faster than a low 15.

 

That one guy ran a 15.3 stock with his t-5 transmission. I'm guessing mid to low 15's. How many miles are on her?

 

thats the joke.....175,000 miles.

 

It all depends on the driver,conditions, and the tune of the car. All of those miles is a disadvantage if the previous owners were harsh on the car. With all of those mods Exhaust,intake,chip,gears,radials, ect you COULD run a 14.9, BUT dont plan on it. Id plan on 15.3's and if you do better at least you wont be disapointed. L03's are tough engines to build beacuse unlike the HO Ford 5.0, the L03's have a tiny peanut cam, and very restrictive heads. That was why I ditched my old LG4 beacuse it didnt have much potential. My full bolt on LG4 was only running 14.9-15.3's, and it had low miles. Now my full bolt on L98 runs 13.5's all day long. If you are looking to race id get a better motor, or think about engine work heads,cam,blower ect

 

Actually the reason the ford 5.0 does so much better than the chevy 5.0 is because the Ford uses a 4" bore where as the chevy uses a 3.75" bore, the extra 1/4" allows for better flow around large valves.

 

Everything about the ford 302 was better than the chevy 305 pretty much.