i was just wandering what people were running with stock 305's because i got a cam and intake on my '84 Z28 and the best i could get it to run was 15.4 with 3.23 gears. What i'm thinkin is the super low compression of my motor isn't supporting my cam at all and i still got factory valve springs so they are probably floatin valves like a *****. my cam was slightly used so i don't know my exact specs but i believe it is a Crane Enegizer cam, 274/274 adv duration, .450/.450 lift. I also have flowtech headers. Also i believe these factory heads may be the worst heads ever produced because it has no top end whatsoever.

 

16's.

The factory heads are about the best they ever installed on the production line. The cause of "no top end whatsoever" is primarily exhaust (calling Flowtechs "headers" is cause for ), with significant contribution from the air cleaner. Plus, factory springs with those exhaust rotators are float waiting to happen, especially with a higher lift cam.

 

there's no way my 305 is completely filling my headers and my heads have small 1.84 1.50 valves

 

Maybe not, but Flowtech's are designed and built pretty poorly.

A lot of people have gotten great gains out of porting those heads.

 

they gotta be better than manifolds

 

1.84 valves are plenty for a 305. TunedPort335 is running 13.40s with his stock untouched heads. Not sure why your 305 is performing the way it is, if that motor was an L69 you should have been runing 15.0-15.3 bone stock. L69s can actually rev a bit too, factory redline is 5500rpm, hardly the soggy 4700 rpm power peak the rest of us TPI guys enjoy. Check your timing, put valvesprings on it, good headers and a good cat back and go mid to high 14s already.

 

nah the 5 spd cars can rev pretty hard... umm I would get rid of the $100 headers, are you sure you didn't buy a smaller cam?

Stock 305's run from 17-16's LG/L03.. 15/high 14's L69, 15's deep 14's LB9(L98 cam).

 

i ran a 16.1 with a stock 305TBI and 2.73 rearend but i just installed 3.42 gears and posi carrier and a buddy gave me a cam but doesnt have any box or paperwork but says cr 274so im assuming its a crane cam, anyone know if its a good cam to install?

 

i ran 15.4 with tpi on top of a l03 peanut cam and swirl port heads
it ran 16.1 with the stockb tbi on top of the same engine the runs where weekend before swap and weekend after swap no other parts changed
once i changed the engine to the lb9 that came with the tpi unit it ran 14.6 after that to many mods to compare

 

I have an L69 with headers (not good ones), RPM manifold, Holley 600, 3.73 gears. It runs 14.5 with a 2.1 60ft.

 

See sig.