Newbie Question! 1971 350 Rocket Horsepower Rating?
#1
Newbie Question! 1971 350 Rocket Horsepower Rating?
Hey, I've been looking a bit and I can't seem to find the horsepower ratings for the '71 350 Rocket engines. I was under the assumption that they were in the area of 310-320 like they were in 69, but I'm also aware the ratings went downhill faster than a rock thrown off Mount Everest in 1972.
Edit: Should have posted this in the newbie section. Bear with me.
Edit: Should have posted this in the newbie section. Bear with me.
Last edited by Zrzoun; July 6th, 2015 at 03:37 PM.
#4
2 bbl: 240 hp @ 4200 RPM, 350 lb.-ft. tq. @ 2400 RPM.
4 bbl: 260 hp @ 4600 RPM, 360 lb.-ft. tq. @ 3200 RPM.
These are gross figures; it was the last year they were used.
The link, while useful doesn't actually answer OP's question. I did a CO search and couldn't find the answer. Had to use other resources.
Welcome, Zrzoun. Post some pictures of your '71 when you get a chance.
4 bbl: 260 hp @ 4600 RPM, 360 lb.-ft. tq. @ 3200 RPM.
These are gross figures; it was the last year they were used.
The link, while useful doesn't actually answer OP's question. I did a CO search and couldn't find the answer. Had to use other resources.
Welcome, Zrzoun. Post some pictures of your '71 when you get a chance.
Last edited by BangScreech4-4-2; July 6th, 2015 at 05:07 PM. Reason: Addendum.
#7
2 bbl: 240 hp @ 4200 RPM, 350 lb.-ft. tq. @ 2400 RPM.
4 bbl: 260 hp @ 4600 RPM, 360 lb.-ft. tq. @ 3200 RPM.
These are gross figures; it was the last year they were used.
The link, while useful doesn't actually answer OP's question. I did a CO search and couldn't find the answer. Had to use other resources.
Welcome, Zrzoun. Post some pictures of your '71 when you get a chance.
4 bbl: 260 hp @ 4600 RPM, 360 lb.-ft. tq. @ 3200 RPM.
These are gross figures; it was the last year they were used.
The link, while useful doesn't actually answer OP's question. I did a CO search and couldn't find the answer. Had to use other resources.
Welcome, Zrzoun. Post some pictures of your '71 when you get a chance.
#8
This has led me to think the 68-70 ratings were way inflated. Note that for 70 there is no distinction between singe exhaust and dual exhaust, nor between auto trans and manual trans even though we now know the MT cars had a much hotter cam than the AT cars.
#9
#10
I wasn't aware this was an SBO thing, but as the owner of a THM400 325 hp 400G, I've always felt ripped off when I thought about those manual transmission guys flaunting their 350 hp.
Did they actually use different cams in identically-rated MT and AT-equipped 350s? I know this was a trick other manufacturers used (the Mopar 340 comes to mind) but I thought Olds would at least vary the rating to reflect the cam used.
#11
Thanks for all the replies, guys. Sounds like I won't be too disappointed if I end up with a '71 instead of a '69 or a '70, which was what I was worried about.
#12
I wasn't aware this was an SBO thing, but as the owner of a THM400 325 hp 400G, I've always felt ripped off when I thought about those manual transmission guys flaunting their 350 hp.
Did they actually use different cams in identically-rated MT and AT-equipped 350s? I know this was a trick other manufacturers used (the Mopar 340 comes to mind) but I thought Olds would at least vary the rating to reflect the cam used.
Did they actually use different cams in identically-rated MT and AT-equipped 350s? I know this was a trick other manufacturers used (the Mopar 340 comes to mind) but I thought Olds would at least vary the rating to reflect the cam used.
Last edited by GEARMAN69; July 7th, 2015 at 04:33 AM.
#14
Well, best of luck on your quest. No reason to avoid the '71-2's!
#15
Your welcome, I thought I did answer. The 68-70 350 before the 70-1/2 change on manual trans show all 310 hp 350 4 barrels getting the same 250/264 187/200 .400 cam then only in mid 1970 production year over the Winter of 69/70 a change on manual cars to the much better 286/286 210?/210? .472 cam. It is very suspect to me on the 310 hp happening with the 250/264 cam and the known poor flowing stock SBO head, it seems you would need atleast that larger 286 cam to get that but maybe not IDK. Maybe someone can chime in that has tore down a 68-69 4 speed 350 310 car and verified the OEM cam that was in it?
#16
No, not really. Back in the early 80s in high school I regularly raced my 70 Supreme (350-4bbl, TH350, dual exhaust, 2.56 rearend) against a friend's 71 Supreme (350-4bbl, TH350, dual exhaust, 2.56 rearend) and the cars were close off the line, through 1st gear then I pulled ahead at the top of 1st. I was severely depressed that my "310 HP" engine didn't totally spank his wimpy, low compression 260 HP engine.
This has led me to think the 68-70 ratings were way inflated. Note that for 70 there is no distinction between singe exhaust and dual exhaust, nor between auto trans and manual trans even though we now know the MT cars had a much hotter cam than the AT cars.
This has led me to think the 68-70 ratings were way inflated. Note that for 70 there is no distinction between singe exhaust and dual exhaust, nor between auto trans and manual trans even though we now know the MT cars had a much hotter cam than the AT cars.
#17
Your welcome, I thought I did answer. The 68-70 350 before the 70-1/2 change on manual trans show all 310 hp 350 4 barrels getting the same 250/264 187/200 .400 cam then only in mid 1970 production year over the Winter of 69/70 a change on manual cars to the much better 286/286 210?/210? .472 cam. It is very suspect to me on the 310 hp happening with the 250/264 cam and the known poor flowing stock SBO head, it seems you would need atleast that larger 286 cam to get that but maybe not IDK. Maybe someone can chime in that has tore down a 68-69 4 speed 350 310 car and verified the OEM cam that was in it?
#18
At least Olds admitted it then. Think about the 1970 W-30 cars, where the AT owners think they have the same HP as the MT cars, when they really just have a W-34 cam.
#21
Definition of 4-4-2 from the Oldsmobile Factory Literature:
1964 (Original meaning)
4: Four Barrel Carburetion
4: Four On the Floor
2: Dual Exhausts
Last edited by GEARMAN69; July 7th, 2015 at 10:14 AM.
#24
#25
#28
Just got a 72 Cutlass Supreme, and although I don't know for sure yet, I believe the engine (350 4bbl), tranny (TH350), and rear end (2.73?) are all stock, other than it was originally single-exhaust and was converted to dual exhaust. As I was waiting for it to arrive (it came from WA and I'm in MA), I was figuring it would be a bit of a dog and had all kinds of ideas running through my head about adding headers, changing the rear-end gears, etc. But when it arrived I was pleasantly surprised. Sure it's not a tire-shredder like the 70 442 I had ages ago, but it ain't too bad. May still look into changing the rear end though...
#30
Just got a 72 Cutlass Supreme, and although I don't know for sure yet, I believe the engine (350 4bbl), tranny (TH350), and rear end (2.73?) are all stock, other than it was originally single-exhaust and was converted to dual exhaust. As I was waiting for it to arrive (it came from WA and I'm in MA), I was figuring it would be a bit of a dog and had all kinds of ideas running through my head about adding headers, changing the rear-end gears, etc. But when it arrived I was pleasantly surprised. Sure it's not a tire-shredder like the 70 442 I had ages ago, but it ain't too bad. May still look into changing the rear end though...
Last edited by Zrzoun; July 7th, 2015 at 05:14 PM.
#32
Ex-girlfriend had a bone stock 71 Supreme 4dr hardtop. 350 4bl, th350, 2.56 posi. A/c, tilt wheel, 56k miles, original down to the plug wires. I just added duals, 2.25 pipe, crush bends, nothing special at all. That damn car would run 15.8 at 88 mph all day long, never shift into 3rd. Hit the lights right at the top of 2nd gear. Real fast? No, but damn respectable. Heavy car, ever look under a 4dr hardtop? Extra frame built into the body tub. Great car, wish I had it today.
#33
Ex-girlfriend had a bone stock 71 Supreme 4dr hardtop. 350 4bl, th350, 2.56 posi. A/c, tilt wheel, 56k miles, original down to the plug wires. I just added duals, 2.25 pipe, crush bends, nothing special at all. That damn car would run 15.8 at 88 mph all day long, never shift into 3rd. Hit the lights right at the top of 2nd gear. Real fast? No, but damn respectable. Heavy car, ever look under a 4dr hardtop? Extra frame built into the body tub. Great car, wish I had it today.
Thread
Thread Starter
Forum
Replies
Last Post