"HIPO" was term used by Ford back in the 60's I believe was an abbreviation of HIgh Performance Option. Chevy used "HI PERF" for the Big Blocks and even some of the daily driver versions had "HI PERF" cast into the blocks and heads. They also used SPHP on some of the small blocks for "SPecial High Performance".

 

Very interesting facts,not to jump on this post but mine is a 305h does the H mean anything.

 

Very interesting facts,not to jump on this post but mine is a 305h does the H mean anything.

How about 305 "H.O." ? H.O. = High Output

 

Not to get off topic but the H is then engine code. My 86 cutlass had a 305 and the eight digit of the vin was H.

 

Not to get off topic but the H is then engine code. My 86 cutlass had a 305 and the eight digit of the vin was H.

Or it could be that.........

 

How about 305 "H.O." ? H.O. = High Output

Was there ever a 305 that was considered "high output?" To me, the 305 always meant the exact opposite.

 

Yep, there were a few 305 HO used, I know the camaro got them in the mid eighties.

 

I do not know if they were standard with the Monte SS or an option. It still wasn't much.

 

The 305 HO was an option for the Z28 (3rd Gen) carbed.
Camshaft;
305 intake lift, 0.234 exhaust, 0.257
305HO intake lift, 0.269 exhaust, 0.276

Compression for the HO was 9.5 : 1 over 8.6 for the regular 305.

 

Didn't the 305 HO have better heads too? If they did how do you distinguish them from regular heads? I was told I can put them on my 283 but I haven't gone that far on my project yet and I would like to know. Thanks

 

I´m using Haynes and Chiltern for the info and they do not mention different heads for the HO.
For the 3rd gen Camaro it only appeared for ´84, ´85, ´86.
HP for the regular 305 was 150 @ 4000rpm, torque was 240 @ 2400rpm.
For the HO HP was 165 @ 4200rpm, torque was 250 @ 2000rpm.

 

I believe the H.O. heads are casting number 14014416. My 86 cutlass supreme brougham (canadian car) had a 305 with these heads, and a 4bbl from the factory, i'm pretty sure it was 9.5:1 cr too. It also had a 200-4r and f-41 suspension.