3 Engines 155HP
 

67 AMC 232, 66 Chev 250, 79 Chev 350. My 64 Rambler could run circles around the P/U with a 250 but understandable since it is about 1/2 ton lighter.

Between 1966 and 1979 did they change how they rate HP? It seems the 350 should have more. It has a better cam, dual exhaust and no pollution stuff so maybe it is a bit more now than the original 155, however they rate it.

I'll have to put my son back in the Rambler and have him try it against the truck. I know even with a load of horse manure that I just picked up it is a lot sportier than with the old 250.

Re: 3 Engines 155HP
 

I don't know when they changed but the new way claims less horsepower. I think in the 60s was rated with no accessories, after was with. Hopefully someone else knows more lol

Re: 3 Engines 155HP
 

The change in HP ratings to SAE came in 1972.

Re: 3 Engines 155HP
 

Basically as I have read, prior to 72 engines were rated gross HP with no accessories, headers even a electric water pump. The way they dyno engines these days. After 72 it was still on a dyno, but with full exhaust and accessories. For example per the GM documentation on a 69 350, it is listed as 255 @ 4600 gross and 195 @ 4000 net

Re: 3 Engines 155HP
 

I don't know of any 350's ever rated at 155hp.

Re: 3 Engines 155HP
 

I wish I would have kept the reference but it really surprised me too. The 250 had a one barrel and the 232 had a two barrel so that I could understand them being the same. I'll try and find that reference again but it seems that in 79 the 350 was rated really low.

https://www.autotrader.com/car-news/...-engine-258659

I guess they got as low as 145 in 1975 so I believe what I read is true.

Maybe we will someday cross paths with some heads with smaller combustion chambers to pick up the compression ratio a bit. I'm not complaining though because at the present it is doing just fine.

Re: 3 Engines 155HP
 

I had a 350 from a 74 Chevelle IIRC, ran the numbers and said 140.

Re: 3 Engines 155HP
 

My ‘motors’ manual from 1976 shows a 145 hp 350 starting in 1973 and continuing onward.
The 305 in 1976 had 140hp.

The amc 236 had unreal bottom end grunt. I rode in one up the hills in Wellington NZ. Pulled along in 3rd gear without a whimper. That was a 3ott rhd.