Yesterday I dynoed my 305 with the vortec heads and recorded a best pull of 239.5 RWHP @ 4700 RPM and 299.7 RWTQ at 3700 RPM. This is approximately equal to 280 flywheel HP and 350 FT/LBS of torque at the flywheel. I believe there is more HP in this combination because my air/fuel ratio went from 13:1 all the way down to 11.5:1 at max power. The 11.5:1 air fuel ratio is way rich and is lowering the max power reading. I was using the stock chip and stock 19 LB injectors lowered to 40 PSI when I recorded the highest numbers. I am going to have to get the chip reprogrammed to get all of the avialable power out of this combination.

Then today I went to the drag strip and recorded a new best ET of 13.53 at 100.92 MPH with street tires and good low wind conditions. I am hoping for 13.40's in the future.

 

Those are decent power numbers and great track times. I hope you can squeak some more out of it with tuning.

 

I was fortunate enough to witness this sweet run! Keep it up, it's great to see the 305 breathin' some fire. :hail:

 

Did you port your base or runners at all? Good times. I wish my 305 could pull that.:hail:
Later Barrett

 

mid 13....hummm...my goal

 

Me too...

 

how is that cam idle in your car?

 

Makes me want my 305 back

 

what springs are you using in those heads with that cam?

 

To answer some of your questions:

1. The intake manifold and runners are not ported but they are matched to each other.

2. The cam idles smoothly at 750 RPM with an aggressive tone.

3. The springs are from Competition Products part number VSA 4. They have an installed height of 1.78 and can handle .570 lift, they are 1.25 O.D., have a seat pressure of 125 LBS with an open of 340 LBS. They are purchased as a kit that contains springs, retainers, and valve locks for $69.95. If you want the springs only, they are 98212 part number.

 

Damn thats some pretty heavy lift pressure

 

will the Vortec heads mate with the TPI intake?...

 

no they won't, you need the special intake manifold for them.



wow, those are some excellent numbers. i'm doing simialar mods on a 355 (currently have 305) with little higher gears(3.73's). looking for good deals on vortec parts right now then i'll begin. hoping for similar times, but with a 350 i'm hoping low 13's...oh ***.....can't wait!!!

good luck on the tuning.

:hail: :hail: :hail: