The Vortec 305s are actually pretty impressive in stock form. My parents had two 2WD Vortec Extended Cab Short Bed pickups that were equipped just about identically. One had the Vortec 305/3.42 rear axle and the other had a Vortec 350/3.73 rear axle. From a seat of the pants perspective, the Vortec 305 felt just as fast as the Vortec 350. I'm guessing instrumented tests would have shown some differences, but I didn't drive the 305 and say "boy I wish I had the 350". Once you start modifying them, though, the advantage tips towards the 350.
DILYSI Dave wrote:
iceracer wrote:
Didn't some of the IROC's have 305's ?
Mine did. 1985 IROC with the 5.0 HO. Electronic quadrajet topping 165 horses of daisy-pulling power...
Actually, the 1985 H.O. had 190hp, base motor was 165. Thats the thing to remember, these engines were around for so long that there a ton of different versions out there.
Gearheadotaku wrote:
DILYSI Dave wrote:
iceracer wrote:
Didn't some of the IROC's have 305's ?
Mine did. 1985 IROC with the 5.0 HO. Electronic quadrajet topping 165 horses of daisy-pulling power...
Actually, the 1985 H.O. had 190hp, base motor was 165. Thats the thing to remember, these engines were around for so long that there a ton of different versions out there.
I thought the TPI motor was 190.
The HO in my Monte Alleges to have 180 horses, but they feel like they were pulled out of line at a glue factory.
TPI ranged from 195-230 depending on year and equipment.
1985 was 215, possibly auto trans only.
beginning in 1988 (i think)G92 cars had a better cam and a 5500 redline vs. a 5000 for the "small" cam.
All convertibles and autos got the small cam. The 5-speed w/G92 go the "big"
Hp difference was 15-30 depending on the year.
I doubt in the extreme that the 305 in 1985 pushed 215 net horsepower.
You can make decent power cheap. Had one in my Nova with 176,000 miles that ran 12.8 with a .447" lift cam. But, if you had to spend $50 to get a 350 core or $150 to get a runner, I would use the 350 before touching a free 305. If you have the 305 and it's in the car and you don't have provisions to pull it, it is a SBC and it will run. The valves are shrouded so don't expect any magic. But don't kick it to the curb either. The stupid thing will last forever. After I race the one mentioned about for 2 seasons, it was installed in a Blazer and ran over 10 years as a DD.
The one in my 83 Z28 didn't feel too bad...
pres589 wrote:
I doubt in the extreme that the 305 in 1985 pushed 215 net horsepower.
Check out 3rdgen.org. they have charts for, well, all the 3rd gen f-bodys.
Some mag, Hot Rod or CC did a 305 stroker build w/ vortec heads. Odd, but it made good power on the cheap!
pres589 wrote:
I doubt in the extreme that the 305 in 1985 pushed 215 net horsepower.
the LB9 TPI engine did. i had one from an 85 trans am in my 80 camaro. the big difference i believe was the cam.
Oh. Didn't think there was TPI on the 305 until 1986. For some reason I thought they were still Cross-Fire setups in 1985. Never mind. Slightly higher than expected but a lot better than the Cross-F setup.
