"71 455 stage 1, bored 30 over with forged pistons & total seal rings. Rods were polished, resized & reconditioned. TA 310 hy cam(degreed at 105i), shorty headers, roller rockers, alum pulleys, HEI by Dave, factory stage 1 Q-jet & settings. Performer intake & port matched, steel heads have mild intake porting and have been resurfaced & unshrouded valves, block line honed and oil mods made, yet NOT decked . Deep steel oil pan from Steve R. I think compression is around 9:1." Well after the cam breakin, it didn't want to idle and made it hard to get the timing right.... So as it turns out, the Q-jet I rebuilt was leaking some air.:ball: :ball: Then we popped on a new Demon, and got it working right. The 1st pull made 431 hp. He thought it was running rich, so I reduced the jets. It DID NOT like that. So then bumped up from the originals, and we made 436.6 hp. Then we quit because it was after midnight. I would not want to live any closer to his shop.:laugh: He thinks he may get to 450.o No: I have to go out of town until Sat, so I can't do much more than call around lunch. I'll update tonight if we have some new results. Thanks for all the help, Dan:bglasses: Guess I need to get a hold of Mr Osborne.....who has his info?
Buick Very good Dan! I thought I heard thunder late in the night, turns out it was probubly a Buick coming to life. Congrats:beer
Another update... I was on my way to the airport when I called around noon. I was told they hit 450.5 hp and 537 '# of torque after they messed with the timing & distrib springs!!!:3gears: I hate NOT being there for all of it:af: , but what else could I do (I have to work for a living). How did I pick that cam? I looked in TA's catalog and read "you'll notice you put a cam in"!:laugh: I'm an idoit, not a racer.:laugh: This is the 1st Buick 455 I've ever built.:grin: :grin: :grin: :bglasses:
Who could argue with those numbers, with that small of a cam! The reason I asked was that you could get more power with iron heads by crutching the exhaust with a little more duration. I didn't really see a cam in TA's list that would be appropriate though. Maybe a 288-94H? Anyway, great job! Those are great numbers. Are those static numbers, or are you doing dynamic pulls where you run it up through the rpm range and back to idle?
Oh my, definitely on an engine dyno... I'll do the chassis dyno, but the car must be ready first.:ball: And reality will hit, and those # will suffer greatly... The dyno has MSD, I'll be using HEI. I will have exhaust hooked up, instead of open headers, and I'll use an air cleaner, power steering & an alternator, a fan mounted on the water pump, all robbing power. Then the most important fact, getting the power to the rear wheels.....Yep, a whole new ballgame. Isn't there about a 20% to 30% loss to the rear wheels? I don't know. We were doing dynamic pulls, and those were peek #'s. The peek torque was around 3,400rpm, and peek HP about 5,000 or 5,300rpm if I recall correctly.
Dan, Those are fantastic numbers. Just imagine what you could do with fully ported or aluminum heads (my own dream combo). George
I had one more advantage I just thought of.. He uses racing (blue) gas, and I forgot to find out what octane. I'm sure the gas really helped. My avg HP was 401.8 and avg Torque was 505.:bglasses: One of the guys there told me at 5,250 rpm, the Torque should = the HP. Mine shows 443'# and 444.2hp at 5,200rpm, so I'm sure that is true. I never got a chance to ask why this is true. So, who can tell me why??? I'm just curious.o No:
Re: I had one more advantage I just thought of.. I think you'll see the answer within the formula... horsepower = rpm x torque / 5252 Since the # 5252 is the constant, horsepower and torque will always cross at that rpm.
Dan, I read an article a little while back (I believe in Hot Rod) that was testing power loss through a vehicles accesories and transmission. One of the cars tested was a 71 GS Stage 1. With A/C, power steering, TH 400 and water pump mounted fan the car put %70 or the engines power to the rear wheels. %30 power loss is kind of a lot, ya? Of course an eletric fan, no-A/C, and perhaps a trick kit for the TH400 would bring those numbers down a bit. I've heard as a rule of thumb that the drive train will suck %15 of the engines power.
Dan, The gas might not be helping you at all. They normally run race gas as a safety feature until you get the timing dialed in. My engine actually picked up a few hp when switched to 93 oct pump premium. BTW, those are great numbers! 450hp is pretty stout for something that idles like a pussycat
